No new Einstein
John Baez
relativity, why is there no new Einstein today?
Read what Lee Smolin has to say:
David Park
"John Baez" <ba...@galaxy.ucr.edu> wrote in message
news:da2rmo$c8v$1...@glue.ucr.edu...
Having read Lee Smolin's article I would like to make some comments.
Smolin is probably right that some method is needed to support young people
who can devote a lot of time to their own approaches to fundamental science
questions without coming under the thumb of the 'old hands'. But to think
that government or foundations can somehow pick most of the good bets and
fund them is questionable. I wonder if Einstein would have been funded under
such programs before 1905? Einstein had some elusive quality that enabled
him to contribute to physics that wasn't recognized until he actually did
contribute. After that he got all the support he wanted.
Such programs as Smolin suggests might end up supporting adequately bright
people with an interest in the prestige of the position and political or
family
connections, but not necessarily with a deep interest in ideas. How about
enticing more sons and daughters of the rich into science? They can do what
they want. Look at Darwin. How about using lax work rules at technical
companies and institutions? Didn't that help Einstein? How about keeping
open to ideas from outside academia. Isn't that how Hardy and Littlewood
promoted Ramanujan?
How about better promoting science among the public in general? Not the
wiz-bang, isn't that exciting, aren't we great stuff, but actually doing
things in mathematics and science. How about devoting more effort to
actually teaching science?
Even if academia will never be the source of EVERY great idea in science and
physics it will still be the clearing house. They must keep their eyes open
for contributions from outside their own select community. When people in
academia only accept emails from .gov or .edu domains they may be shutting
out future contributors. (Ok, Einstein would probably have had a .gov
domain, and there are lots of kooks. But that's the price.) When government
technical libraries that used to be open to the public are now closed to the
public (such as the NIST library in Gaithersburg, Maryland) that doesn't
help lone scientists.
There are many things that can be done to nurture science and physics and
future Einsteins besides additional government or foundation funding
programs.
David Park
dj...@earthlink.net
http://home.earthlink.net/~djmp/
Uncle Al
To obtain the discoverer the discovery must exist to be discovered.
What alternatives for such discovery remain?
1) A sea change in physics from a bold new paradigm. Contemporary
prediction vs. measurement can agree to 14 significant figures. Has
everybody has been remarkably blind, geocentric epicycles vs.
heliocentric orbits? A new Einstein would bell the cat. New insight
from (a)symmetries of deep maths could do it, as would a nice
accidental observation.
2) Empirical falsification of postulates. The only ones that don't
look rock solid are the Equivalence Principle and Lorentz Invariance.
Uncle Al has them both on trial with the currently running full parity
Eotvos experiment. Alan Kostelecky is vigorously hounding the latter,
as is Eric Adelberger.
http://www.mazepath.com/uncleal/qz.pdf
http://www.physics.indiana.edu/~kostelec/faq.html
http://www.npl.washington.edu/eotwash/spin1.html
http://www.npl.washington.edu/eotwash/publications/cpt01.pdf
3) Standard Model prediction violation in the highest energy
particle accelerators and the supercon magnet axion search. Proton
decay search in Super-Kamiokande. The Standard Model is robust.
<http://bulletin.cern.ch/eng/articles.php?bullno=10/2005&base=art&artn...>
CAST, 1/3 the way down.
http://cast.web.cern.ch/CAST/
http://collargroup.uchicago.edu/projects/axion/www.unifr.ch/physics/3...
4) Nothing. Boring but possible.
Theory can predict anything and everything exactly, if not directly
then by perturbation or Yukawa fringing, etc. What lacks is
experiment. Given that grant funding will not support experimentation
without theoretical justification and prior citation, progress (if
any) will be accomplished by the insubordinate undeserving who
embezzle resources.
IBM/Zurich threatened Bednorz and Mueller with discharge for cause and
prosecution for misappropriation of laboratory funding. The guys were
supposed to be creating deep cryogenic high Cp ceramic insulation for
supercon filaments. One supposes their Nobel Prize in Physics for
discovering high temp ceramic superconductors motivated IBM Management
to back off their threats. 20 years of serious sweat later we still
don't have a theoretical model to construct better (temp and
engineering) ceramic supercons.
The discovery of high temp BCS supercon MgB2 was purely accidental.
Folks were doing combinatorial studies on multi-element ceramic
supercons, and one *corner* of the search had the fat numbers.
Directed research since then has made no substantive progress. They
are stuck in a new rut - by the book, SOP.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf
Cl.Massé
da2rmo$c8v$1...@glue.ucr.edu...
> On the hundredth anniversary of Einstein's discovery of special
> relativity, why is there no new Einstein today?
How can we say he doesn't exist? He surely exists, but experiences great
difficulties to be published: he works neither on superstrings, neither on
supersymmetry, and neither on non-commutative geometry.
--
~~~~ clmasse on free F-country
Liberty, Equality, Profitability.
René Meyer
Frank Hellmann
Einstein is almost by definition outside of anything that can be
encouraged through academic structures, since it can not be detected by
these structures. They are by neccessity blind to this mode of thinking
that is crucial for the next breakthrough or it would have been
achieved (especially considering the number of very clever people
pounding away on this question)
Perhaps a better question would be why Andrew Wiles had to be so sneaky
about what he was working on, why there are no new Bohrs, Paulis,
Diracs, Heisenbergs.
And here I think Smolin is spot on. Of course it doesn't sound as sexy
as a new Einstein, and he is looking for public money, so it's a fair
argument I'd say... ;)
F
mark...@yahoo.com
> On the hundredth anniversary of Einstein's discovery of special
> relativity, why is there no new Einstein today?
How do you know there isn't?
The question, more properly, is: IS there a new Einstein lurking around
somewhere today.
The analogue, today, nearly 100 years past, is that you have a
situation today just like 1905, where you have two seemingly
irreconcilable theories, and people (unbeknownst to themselves in some
cases) have already laid out the essential foundation of its resolution
(e.g. Smolin & Markopoulou, Penrose, etc.), while in the meantime, the
mainstream is off on an modern-day Ether Primrose Path. The analogy,
in fact, is made complete by the fact that the general resolution is
coming fully in sight now, as it did then.
Let's take a look at the issue: the incompatibility of quantum theory
and general relativity, and see how its focal issue is resolved: the
issue of general coordinate covariance.
Squark wrote:
> The essence of the Unruh effect is that a uniformly accelerated
> observer sees the QED vacuum as a thermal equilibrium (black-body
> radiation). The later, as opposed to the former, is not even a
> pure state but a mixed one. This raises the interesting question
> of what is the general transformation from the inertial observer
> to the accelerating one on the space of mixed states.
Well, first you have to understand that the term "frame" has little to
do with what relativists call a frame. It refers to a timelike field.
The one associated with the Rindler vacuum (and the ordinary inertial
vacuum) is a Killing field, but I'm not sure how essential the
assumption is that it also be Killing.
The nature of the vacuum depends entirely on which frame is used. As
Penrose pointed out, there is no covariant distinction between quantum
noise and thermal noise: what appears as quantum correlations in one
frame, gets rendered as thermal noise associated with the cut-off
boundary imposed by the causal horizon.
The reason you get a thermal state is because the frame associated with
the Rindler vacuum creates a causal horizon, at the boundary which
envelopes the flowlines corresponding to that part of the spacetime
you're in. There are 2 separate sections in the spacetime, each
bounded by a null hypersurface, which functions analogously to an event
horizon.
The thermal state is directly in associated with the horizon. The
reason states are mixed is because in the Rindler vacuum they are mixed
RELATIVE states created by phase averaging (or "coarse graining", as it
is generally called) over the horizon. This is where the quantum
correlations seen in the Minkowski vacuum get rendered as thermal
correlations.
The general transformation is the Bogoliubov Transform. I think the
reason the timelike field is required to be Killing is so that the
transform be linear. But whatever it is, the key point is that the
transform is NOT complete. In particular, the operators corresponding
to the sector that lies outside the causal horizon don't get translated
properly in the Rindler frame.
The general situation is as follows: you can partition spacetime into
compact regions, each region having its own timelike field, and each
region bounded by 2 null hypersurfaces -- Alexandroff Intervals, in
essence. Between any two such regions will be a partial transform
whose respective domains in each direction overlap. The net result is
that each region sees part of what's rendered in the other ocherently,
as a mixture.
The one construction I'm looking at developing is as follows: take the
timelike fields to be such that the flow lines meet at (r=0,t=-L) and
(r=0,t=L), and such that they have tangents proportional to d/dt at
(r=R,t=0). The different flowlines correspond to different
intersection points R, where |R| < L. The enveloping hypersurfaces are
given by |R| + |t| = L, with t > 0 giving you the positive
hypersurface, t < 0 the negative hypersurface.
If the flowlines are hyperbolic, they will generally have the form (r =
a cosh(s) + b, t = c sinh(s) + d). The different selections of the
parameters (a,b,c,d) will give you the different flowlines. This is
constrained so that it passes through (0,-L), (0,L) and for some R,
with |R| < L, (R,0).
The hypersurfaces R_l, -1 <= L <= 1 are spanned, such suitable scaling
of s, by the flowlines; and the region R is the union of R_l as l
ranges from [-1,1], with the bounding hypersurfaces R_{+/-} being the
limits respectively as l -> +/- 1. Each hypersurface R_l has boundary
H = { (Rn,0): |n|=1 } -- the same 2-sphere.
Now, a natural question is to determine what the Bogoliubov transforms
look like between different Alexandroff Intervals, taking different
points (r1,t1)-(r2,t2) in place of (0,-L)-(0,L). This implements the
quantum analogue of a coordinate transform, thus recovering some
semblance of the Relativists' notion of a local coordinate frame from
the quantum notion of a frame=time-like streamline.
What's particularly interesting about these frames is that they are all
self-contained in the sense that nothing propagates outside the region,
except through the 2 boundaries, which are both null and play the role
of local causal horizons.
That means you can do mini-quantum field theory inside the Alexandroff
Interval -- except the vacuum state must now be a thermal state or some
more elaborate type of mixed state.
Each surface R_l is, in effect, a compact Cauchy surface. So, you can
write down a symplectic structure using well-established methods --
many of which have problems when the Cauchy surfaces are not compact,
that are entirely dodged in this setting.
The difference from the Rindler vacuum is that the accelerations of the
flowlines here are radial and approach infinity at the horizon. I'm
not sure, yet, of the ramifications of this and of the construction in
general. It's still something I'm looking into.
Another key feature is that this type of self-contained mini-quantum
theory has the global element removed entirely from it. You're staying
within a compact, locally hyperbolic region, of spacetime. Therefore,
invoking a correspondence principle
What goes in Vegas stays there:
What works in the region R works there, regardless of
what the global structure of the spacetime R is embedded
in is.
then you're able to do generally covariant quantum field theory in
spacetimes, both globally hyperbolic and non-hyperbolic -- even ones
beset with all sorts of causal anomalies, such as time
non-orientability, time travel loops, etc.
>
> Read what Lee Smolin has to say:
>
> http://math.ucr.edu/home/baez/no-new-einstein.pdf
>From hil...@math.washington.edu Sun Jul 3 21:59:33 2005
From: tes...@um.bot
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René Meyer mentioned
> http://www.sciencemag.org/cgi/content/full/309/5731/78b
Nice, but doesn't the second to last question rather miss the point?
(Of course all the zeros are -complex numbers-. I guess the editors took
their own advice: "Don't sweat the details"!)
"T. Essel"
tes...@um.bot
I.Vecchi
Uncle Al wrote:
> John Baez wrote:
> >
> > On the hundredth anniversary of Einstein's discovery of special
> > relativity, why is there no new Einstein today?
> >
> > Read what Lee Smolin has to say:
> >
> > http://math.ucr.edu/home/baez/no-new-einstein.pdf
>
> To obtain the discoverer the discovery must exist to be discovered.
> What alternatives for such discovery remain?
>
> 1) A sea change in physics from a bold new paradigm. Contemporary
> prediction vs. measurement can agree to 14 significant figures.
Yup, thanks to 29 "fundamental" constants, hundreds of adjustable
experimental parameters, a predictive tool consisting of DIVERGENT
(sic) series that one truncates at will and, most important, a
scientific community whose jobs, salary and status depend on
aquiescence/gullibility.
Btw, I'd replace "physics" above with "lab phenomenology". The SM
fabulous predictions (unlike humble superconductivity or laser) never
made it to real life applications ... .
IV
Nick Maclaren
In article <DyAxe.2362$aY6...@newsread1.news.atl.earthlink.net>,
David Park <dj...@earthlink.net> writes:
|> "John Baez" <ba...@galaxy.ucr.edu> wrote in message
|> news:da2rmo$c8v$1...@glue.ucr.edu...
|>
|> > On the hundredth anniversary of Einstein's discovery of special
|> > relativity, why is there no new Einstein today?
|> >
|> > Read what Lee Smolin has to say:
|> >
|> > http://math.ucr.edu/home/baez/no-new-einstein.pdf
Inaccessible from here at present.
Special relativity is a bad example. As with Newton's laws of motion
and theory of gravity, Einstein was merely the leader of the pack of
people studying the problem. If he had not published it, someone
else would have done within a decade or two. This does not denigrate
his work - merely pointing out that it was not dependent on his
existence. Someone else would have put Lorentz transformations
together with the observation that the speed of light was invariant,
and special relativity would have dropped out. It does :-)
One can argue that general relativity is one reason that there has
been little progress, and quantum mechanics is another. Both of
them are theories that were applicable vastly beyond any aspects
that could be checked by experiment, and got established before
there was any possibility of much checking. It then became very
hard to publish alternative theories that were equally in accordance
with the facts, or to get funds for experiments based on such
theories.
All right, that is an over-simplification and a bit too harsh, but
there is some truth in it. And the problem with quantum mechanics
is more that it can be fitted to almost any observation rather than
it is uncheckable.
An alternative way of phrasing this is the philosophical observation
that all theories have their domains of validity, and they gradually
cease to model the real universe as you approach the boundaries of
those domains. And new developments are driven by problems caused
by existing theories breaking down. For example, it was the aetheric
theory breaking down that caused Einstein to apply the (existing)
Lorentz transformations to create his special theory.
|> How about using lax work rules at technical
|> companies and institutions? Didn't that help Einstein? How about keeping
|> open to ideas from outside academia. Isn't that how Hardy and Littlewood
|> promoted Ramanujan?
Yes, and the laxness at Cambridge is one of the reasons that it is
still one of the leading scientific universities, despite having
a very small income compared with those in the USA. However, the
current moves are to stop that on the grounds of inefficiency.
|> There are many things that can be done to nurture science and physics and
|> future Einsteins besides additional government or foundation funding
|> programs.
Yes.
Regards,
Nick Maclaren.
galathaea
have always been there
they have not stifled creativity
sometimes they stimulate it
einstein is a great example
everyone's heard the allegations
concerning poincare's work on relativity
and hilbert's work in geometry
and planck's quantisation
crude comments were circulating contemporary to the discoveries
not necessarily because of any strong evidence
but often just because
the others were doing things just as brilliant
and maybe should get some more credit
fame is currency
giving planck, hilbert,and poincare some of einstein's credit
dilutes the argument
and could I also include von neumann?
you're a categorial algebraicist at times
john
you know the importance of his work
in formulating the logic of quantum propositions over hilbert spaces
(there's hilbert again!)
because it gave us something to generalise
dropping any more names is just vanity
but the short list is obviously not short
(tarski, lawvere, connes, witten)
it looks to me like lee is venting the "persecuted minority"
loop quantum gravity is to string theory
(in this respect)
what bohmian mechanics is to copenhagen
or constructivism is to the platonic boolean
it is a clever little alternative
that has not yet convinced a majority of the genre
that it is useful
sometimes
as in the case of the flat earth society
it is good to have criteria
the question is what criteria to have
observation alone does not limit possible models
enough for which we have resources to handle
so although its a good first step for a science
you need other criteria
and resource allocation involves politics
and politics is dictated by currency
like fame
it always has
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
galathaea: prankster, fablist, magician, liar
Cl.Massé
42C6B509...@hate.spam.net...
> To obtain the discoverer the discovery must exist to be discovered.
> What alternatives for such discovery remain?
>
> 1) A sea change in physics from a bold new paradigm. Contemporary
> prediction vs. measurement can agree to 14 significant figures.
I don't think the amplitude of the Higgs field agree with measurement to 14
significant figures. If only there were 1!
> 3) Standard Model prediction violation in the highest energy
> particle accelerators and the supercon magnet axion search. Proton
> decay search in Super-Kamiokande. The Standard Model is robust.
But obviously not a good theory: too many things put at hand, skeletons in
the cupboard...
Tim Josling
> "John Baez" <ba...@galaxy.ucr.edu> wrote in message
> news:da2rmo$c8v$1...@glue.ucr.edu...
>
>>On the hundredth anniversary of Einstein's discovery of special
>>relativity, why is there no new Einstein today?
>>
>>Read what Lee Smolin has to say:
>>
>>http://math.ucr.edu/home/baez/no-new-einstein.pdf
>>
Some more perhaps obvious points.
Physics today is just huge. To learn enough to get to the questions is a
far bigger job than 100 years ago. By the time you learn enough you are
on the way to being an old man.
The cost of experiments. The energy and scale involved in experiments to
test modern theories are enormous and so require lots of government
funding, if it is possible at all.
Tim Josling
backdoo...@yahoo.com
> why is there no new Einstein today?
Why should we expect another Einstein? Isn't that like expecting to win
the lottery twice?
In the article Smolin uses Einstein as an example to critique academia.
Perhaps the problem with academia is just one of the problems of the
contemporary world where results are expected too regularly and
academics must "publish or perish". The major universities aim to
administer themselves as assembly lines, and this approach is copied in
the minor colleges.
Physics has become much more specialized than it was 100 years ago. And
before that it was practised by people in other professions (such as
law). Einstein also read a lot of philosophy. Most physicists today
seem to believe that "philosophy" is just idle speculation or worse - a
pile of unfounded beliefs. Actually, philosophy (in it's broadest
sense) is just about making your thoughts clear, but it seems to have
become a dirty word in physics. What is most important is to not be a
crackpot and to get your articles frequently cited. But before you can
even get to that point you must show-off how smart you are by getting
higher scores - just like a game. To Einstein these things did not
matter at all.
Nick Maclaren
Tim Josling <tej_at_melbpc....@nospam.com> wrote:
>
>Physics today is just huge. To learn enough to get to the questions is a
>far bigger job than 100 years ago. By the time you learn enough you are
>on the way to being an old man.
Um. Yes and no. Much of physics is very secondary, and learning
it is a positive handicap to doing anything new. It is still very
complex, but not as huge as is made out.
General relativity is conceptually very simple, for example, and it
is the consequences of the formulae that are difficult. Many people
have asked some of the real, fundamental questions about it with
very little knowledge of physics - all you need is a good mathematical
background. Of course, asking the questions and providing even
plausible answers are two very different things :-)
For example, I was one of the hundreds or thousands of people who
posed the question "Is Einstein's formula the only one that fits the
known facts?" and could demonstrate that it wasn't. I had already
derived the exponential form (instead of 1/(1-v^2)), because the two
formulae are well-known to be similar (to people with my background).
Of course, that merely states the truism that, before we can be sure
that Einstein's formula extends right up to event horizons, we need
some measurements of behavour close to where it predicts the event
horizons to be. And that isn't so easy to arrange ....
>The cost of experiments. The energy and scale involved in experiments to
>test modern theories are enormous and so require lots of government
>funding, if it is possible at all.
To a great extent that is a consequence of my previous remark that
both general relativity and quantum mechanics are theories that have
domains of validity far beyond what could be measured, and even some
way beyond what can be measured today. There may be some simple,
cheap tests to check on their boundaries, but I can't think of any.
Regards,
Nick Maclaren.
mark...@yahoo.com
> Read what Lee Smolin has to say:
> http://math.ucr.edu/home/baez/no-new-einstein.pdf
"[Einstein] was not unusually talented mathematically. Instead, [he
had] a fierce intellectual independence. [...] The new Einsteins are
unlikely to be easily characterized in terms of research programs that
have been well explored for decades."
And further down below...
"Are our universities, institutions, and foundations doing all they can
to identify and promote [such] individuals..."
which completely misses the point of:
"a fierce intellectual independence"
which means "Stay out of my business, for God's sake! And quit trying
to 'reward' me or give me 'incentives' or whatever other patronizing
buzzword you want to use. Why do you think it's called being
'independent'?!" And this is what the word "fierce" signifies, too.
Asking what can be done misses the point: to quit interfering. Do
nothing. Please.
In a place like North Korea, it might make sense to turn over every
rock to cull out the kids who are ahead of the game and prop them up
(without ever bothering to ask them) -- which they actually do to an
untold Orwellian extent -- in some kind of vast appropriation scheme.
But the essential feature of an individualist society is that people
are able to do things on their own, without prologues of major
institutions ardently trying to extend the long reach of "incentives",
"rewards" and other bureaucracy into their lives -- all of which smacks
of socialism run amok. They (we) don't want rewards or incentives.
That's why it's called being "independent". They just want the
recognition when the job's done, regardless of whether they're in a
patent office or out on the street.
tuppence
> relativity, why is there no new Einstein today?
There is no new Einstien today because there is no new Lorentz from whom to
steal ideas!
porte...@yahoo.com
Sneakiness is not so important if you are really revolutionary in your
ideas. I doubt Einstein had to be sneaky. As Howard Aiken* said "Don't
worry about people stealing your ideas. If your ideas are any good,
you'll have to ram them down people's throats."
*An IBM Engineer, also famous for saying "Only six electronic digital
computers would be required to satisfy the computing needs of the
entire United States". Maybe he is not the best source of worldly
wisdom ;-).
Ilja Schmelzer
> <to...@tata.ti> wrote:
> > "John Baez" <ba...@galaxy.ucr.edu>
> >> On the hundredth anniversary of Einstein's discovery of special
> >> relativity, why is there no new Einstein today?
> > How can we say he doesn't exist? He surely exists, but experiences
great
> > difficulties to be published: he works neither on superstrings, neither
on
> > supersymmetry, and neither on non-commutative geometry.
> ...or not, and "superstrings, supersymmetry or non-commutative
> geometry" are right, to the great chagrin of certain people :-)
Possible but not very probable.
"Publish or perish" leads to an artificial concentration on a few domains
of research: It is reasonable to work in a domain with many journals to
publish your papers.
If you need many citations the effect is the same: Publish in a domain where
many people work. All they can, possibly, cite your papers.
If you have to change your working place every 3-4 years, it has the same
effect: A domain with many groups around the world gives more potential
working places.
Peer review has a similar effect: Even if they are able to evaluate papers
in other domains, scientists tend to favour papers in their own domain.
That's natural, if we assume that they choose their domain of research
because they think that this domain gives the most valuable contributions to
science.
Thus, all these forms of quality control lead to artificial concentration.
Can we hope for something better? I doubt. Every form of formal
control has its weak points. Once scientists are (at least we hope so)
clever, they will be able to misuse them.
IMHO, the best way of quality control in theoretical physics is a large
initial barrier (good education, people have to be able to understand
and to learn the established theories), medium payment (too small
to attract people not interested in science) but no other control at all.
Ilja
Uncle Al
Simple and cheap, to be run in existing apparatus, unambiguous and
reproducible; include gravitation, quantum mechanics, and all of
classical physics. No problem!
Metric gravitation appears from Special Relativity by postulating the
Equivalence Principle; its maths are overall symmetric to parity
inversion as is Newton. Affine gravitation does not postulate the EP;
its maths can be symmetric or antisymmetric to parity inversion.
Metric gravitation is wholly contained within affine gravitation as a
special case. Don't look where they agree, look where they are
disjoint.
If you find two local lumps that empirically reproducibly free fall
differently in vacuum - with different accelerations or along
non-parallel trajectories - then the EP is falsified and metric
gravitation is incomplete (as Euclid fails in hyperbolic or elliptic
spaces given his Fifth Postulate). Drop small stuff close together
(locality vs. tidal forces in Earth's divergent gravitational field)
and look. Simple and cheap.
We know where not to look: all contrasted chemical compositions of
matter, physically spinning bodies (gyroscope balls), spin-polarized
bodies (magnets), binding energies (Nordtvedt effect), superconductors
(Gravity Probe-B); and hyper-spinning, hyper-polarized, hyper-bound,
superconducting neutroniun (binary pulsars). Folks have already
looked and found nothing amiss to 10^(-13) difference/average.
Only *one* possiblity remains! Does a left hand fall identically to a
right hand? Does the Equivalence Principle have a parity violation?
If so, Lorentz invariance is violated (demonstrated anisotropy of
space) and quantum mechanics also falls. If space is anisotropic,
then angular momentum through Noether's theorem is not rigorously
conserved by opposite parity masses, and the remainder of physics
goes down as well. Parity-antisymmetric affine gravitation is a clean
sweep of everything known to be "true" - though only as an
ultramicroscopic perturbation (so far).
Quartz crystallizes in opposite parity crystallographic space groups
P3(1)21 and P3(2)21. Do single crystal bodies of left-handed quartz
fall identically to those of right-handed quartz? The results of the
parity Eotvos experiment will be out in mid-September. There is a 50%
chance a handful of sand will be tossed into General Relativity's
gears.
More than a 50% chance. What originated biological homochirality?
All chiral protein amino acids are left-handed; all chiral sugars are
right-handed. Was it coincidence or is there an intrinsic energetic
bias because space itself is chiral?
LEJ Brouwer
> On the hundredth anniversary of Einstein's discovery of special
> relativity, why is there no new Einstein today?
I think the following words of a very competent 'establishment'
physicist are indicative of why even those of exceptional technical
ability and a deep and broad knowledge of the various research areas of
active research are not likely to be the next Einstein in the current
academic environment:
"For example, physicists have asked since 1926 whether
the probabilistic interpretation of quantum mechanics
is inevitable. Hundreds of people have worked on this
issue for decades, and the answer is essentially Yes,
it is inevitable. It's not surprising that those who
still want to replace quantum mechanics by a classical
theory or something very similar are viewed as
crackpots by most of the physics professionals."
The logic here is fundamentally flawed. The basic claim made is that
there is no point trying to tackle the fundamental problems because so
many excellent physicists have already tried and failed. Einstein, on
the other hands, succeeded, because he instinctively *knew* when he was
right, and followed his instincts all the way.
The next Einstein will be willing to stand up for his beliefs when he
senses (or rather, instinctively 'knows') that he is right - even if
everyone in the scientific establishment believes (or rather 'knows'
because that is what they have been taught, or what everyone else
believes) that that he is wrong, and he will not be swayed by
inherently flawed emotional arguments (which are effectively statements
of blind faith in the scientific establishment) such as those given
above. Unfortunately promising young researchers are not allowed to be
too 'creative' these days as they either risk not getting tenure, or
worse still, not even graduating.
He will do so even at the risk of being labelled a 'crackpot' by
members of the academic establishment - even those who make a point of
weeding out from academic circles and immediately placing into
disrepute any deviant thoughts which do not conform to currently
established views (sadly such actions ultimately stifle creativity, as
talented mainstream academics dare not step too far beyond the accepted
norms lest they be ostracised). Neither will the next Einstein be
swayed by passing fads, and nor will not hesitate to make use of and
further develop promising ideas from the past which have either been
ignored for forgotten.
While the next Einstein will be technically competent, he need not have
extraordinary levels of mathematical knowledge or ability, but rather
should be able to recognise and effectively use those tools which he
feels are relevant and will be useful to make progress. He will not be
shy of trying out unusual ideas or even making mistakes along the way,
as his goal will be the search for truth, and not to impress others
with the number of his publications or citations.
More specifically Einstein believed:
(a) That quantum theory was an emergent theory from an underlying
classical deterministic one.
(b) That there are no singularities in general relativity.
(c) That there exists a classical field theory unifying gravity,
electrodynamics and quantum theory.
(d) That the fundamental (quantum) particles are solitonic solutions of
that underlying classical field theory.
The next Einstein should prove that Einstein was right on all four of
the above counts (otherwise he could hardly be another Einstein, could
he?), and needless to say, will be highly unlikely to receive any
funding for carrying out his research. He will be highly creative yet
of sound judgment, without being tied down ill-founded preconceptions,
and will have excellent intuition, being able to quickly separate
promising ideas from red herrings (the latter is where Einstein really
excelled). In particular, he will realise that quantising gravity is
the biggest red herring in theoretical physics today, and that rather
one should be gravitising the quantum.
Anyone who poo-poos any of the above beliefs/visions of Einstein is
simply not of Einstein's calibre, and can neither hope to be, nor is
worthy of being, the next Einstein.
LEJ Brouwer
> Only *one* possiblity remains! Does a left hand fall identically to a
> right hand? Does the Equivalence Principle have a parity violation?
> If so, Lorentz invariance is violated (demonstrated anisotropy of
> space) and quantum mechanics also falls. If space is anisotropic,
> then angular momentum through Noether's theorem is not rigorously
> conserved by opposite parity masses, and the remainder of physics
> goes down as well. Parity-antisymmetric affine gravitation is a clean
> sweep of everything known to be "true" - though only as an
> ultramicroscopic perturbation (so far).
Nonsense. There are other ways for parity violation to originate which
do not require breakdown either of Lorentz invariance or of quantum
mechanics, or of conservation of angular momentum, or of the
equivalence principle. You just haven't thought of one yet. Einstein,
as it happens, did make a proposal many many years ago which does
allow for parity violation without any of the undesirable properties
you appear to have convinced yourself are unavoidable.
Uncle Al
>
> Uncle Al wrote:
> > Only *one* possiblity remains! Does a left hand fall identically to a
> > right hand? Does the Equivalence Principle have a parity violation?
> > If so, Lorentz invariance is violated (demonstrated anisotropy of
> > space) and quantum mechanics also falls. If space is anisotropic,
> > then angular momentum through Noether's theorem is not rigorously
> > conserved by opposite parity masses, and the remainder of physics
> > goes down as well. Parity-antisymmetric affine gravitation is a clean
> > sweep of everything known to be "true" - though only as an
> > ultramicroscopic perturbation (so far).
>
> Nonsense. There are other ways for parity violation to originate which
> do not require breakdown either of Lorentz invariance or of quantum
> mechanics, or of conservation of angular momentum, or of the
> equivalence principle. You just haven't thought of one yet.
Don't keep it a secret! To criticize is to volunteer.
> Einstein,
> as it happens, did make a proposal many many years ago which does
> allow for parity violation without any of the undesirable properties
> you appear to have convinced yourself are unavoidable.
Tell us. Furnish a citation. Demonstrate how a parity violation of
the Equivalence Principle can be empirically observed, not originate
in spatial anisotropy, and thereby leave everything else intact.
Inquiring minds want to know!
The Weak Interaction is strictly left-handed, but that does not
directly couple to the Equivalence Principle.
Nick Maclaren
Uncle Al <Uncl...@hate.spam.net> wrote:
>
>Simple and cheap, to be run in existing apparatus, unambiguous and
>reproducible; include gravitation, quantum mechanics, and all of
>classical physics. No problem!
And cleans your teeth whiter, too. Some evidence of such a miracle
would add rather more weight to your claims - see below.
>We know where not to look: all contrasted chemical compositions of
>matter, physically spinning bodies (gyroscope balls), spin-polarized
>bodies (magnets), binding energies (Nordtvedt effect), superconductors
>(Gravity Probe-B); and hyper-spinning, hyper-polarized, hyper-bound,
>superconducting neutroniun (binary pulsars). Folks have already
>looked and found nothing amiss to 10^(-13) difference/average.
Not all aspects of physics have been demonstrated even to 10^0
accuracy :-)
>Quartz crystallizes in opposite parity crystallographic space groups
>P3(1)21 and P3(2)21. Do single crystal bodies of left-handed quartz
>fall identically to those of right-handed quartz? The results of the
>parity Eotvos experiment will be out in mid-September. There is a 50%
>chance a handful of sand will be tossed into General Relativity's
>gears.
Fine. Let's wait for that, and the analyses of the result.
>More than a 50% chance. What originated biological homochirality?
>All chiral protein amino acids are left-handed; all chiral sugars are
>right-handed. Was it coincidence or is there an intrinsic energetic
>bias because space itself is chiral?
A good question, with many plausible and even more implausible
answers.
Regards,
Nick Maclaren.
mark...@yahoo.com
> Nonsense. There are other ways for parity violation to originate which
> do not require breakdown either of Lorentz invariance or of quantum
> mechanics, or of conservation of angular momentum, or of the
> equivalence principle. You just haven't thought of one yet.
Uncle Al and I went through that discussion a while back. The
(generalized) teleparallel gravity gives you a geodesic law with an
effective force on the right proportional to the acceleration. If it
were proportional to the velocity, you could incorporate it into a
Lorentz force; which is generally the only kind of force you have
around to talk about. If it's proportional to the acceleration one can
always find a way to contort something that will fit (e.g. by forcing a
redefinition of the connection to get it to fit the modified mass on
each world line); but in the end, there is no real substitute for the
simplest explanation that there is two different kinds of masses
involved.
Teleparallel gravity would not have made the peer-reviewed published
literature, in the first place, had it been nothing more than a fancy
reformulation of General Relativity. A little common sense is in order
here.
mark...@yahoo.com
> More specifically Einstein believed:
> (c) That there exists a classical field theory unifying gravity,
> electrodynamics and quantum theory.
>
> simply not of Einstein's calibre, and can neither hope to be, nor is
> worthy of being, the next Einstein.
"One can give good reasons why reality cannot at all be represented by
a continuous field. From the quantum phenomenon it appears to follow
with certainty that a finite system of finite energy can be completely
described in terms of a finite set of numbers (quantum numbers). This
does not seem to be in accordance with a continuum theory, and must
lead to an attempt to find a purely algebraic theory for the
description of reality. But nobody knows how to find the basis for
such a theory"
-- Albert Einstein, The Meaning of Relativity, 1956 (posthumous)
Ed Hanna
And let's not forget:
In 1936 Einstein wrote that: "To be sure, it has been pointed out that
the introduction of a space-time continuum may be considered as
contrary to nature in view of the molecular structure of everything
which happens on a small scale. It is maintained that perhaps the
success of the Heisenberg method points to a purely algebraical method
of description of nature, that is, to the elimination of continuous
functions from physics. Then, however, we must also give up, on
principal, the space-time continuum. It is conceivable that human
ingenuity will some day find methods which will make it possible to
proceed along such a path." (p. 319.)
In 1940 Einstein wrote that: "All attempts to represent the particle
and wave features displayed in the phenomena of light and matter, by
direct recourse to a space-time model, have so far ended in failure.
.. For the time being, we have to admit that we do not possess any
general theoretical basis for physics, which can be regarded as its
logical foundation. ... Some physicists, among them myself, cannot
believe that we must abandon, actually and forever, the idea of direct
representation of physical reality in space and time; or that we must
accept the view that events in nature are analogous to a game of
chance." (p. 334.)
Both quotes from collected writings found in: A. Einstein. Ideas and
Opinions. (Crown, New York, 1954).
Regards,
Ed Hanna
cma...@yahoo.com
And let's underline:
"... Some physicists, among them MYSELF, CANNOT BELIEVE that we must
abandon, actually and forever, the idea of direct representation of
physical reality in space and time; or that we must accept the view
that events in nature are analogous to a game of chance."
In less diplomatic terms he could have written: "There are good reasons
to waste time of this red herring, but my superior intuition and
philosophical principles prevent me from doing so."
Chris
LEJ Brouwer
> LEJ Brouwer wrote:
> > Nonsense. There are other ways for parity violation to originate which
> > do not require breakdown either of Lorentz invariance or of quantum
> > mechanics, or of conservation of angular momentum, or of the
> > equivalence principle. You just haven't thought of one yet.
>
>
> > Einstein,
> > as it happens, did make a proposal many many years ago which does
> > allow for parity violation without any of the undesirable properties
> > you appear to have convinced yourself are unavoidable.
>
> Tell us. Furnish a citation. Demonstrate how a parity violation of
> the Equivalence Principle can be empirically observed, not originate
> in spatial anisotropy, and thereby leave everything else intact.
> Inquiring minds want to know!
>
> The Weak Interaction is strictly left-handed, but that does not
> directly couple to the Equivalence Principle.
Okay, I'll tell you - but you must promise to start being nicer to
people and stop being such a bully! :)
The reason all neutrinos are left-handed is because gravitons are their
own antiparticle. Furthermore, the reason that no other spinors have
only a single handedness is because the neutrino is *not* its own
antiparticle.
When I see some evidence of behavioural improvement, I will happily
reveal the rest of the story. Otherwise, I hope to have a preprint out
within a month or so.
- Sabbir
acl
100 times and it fails, then it can't be done? It's exactly the logic
that is used in science (namely, inductive, rather than deductive).
Postulating, as you do, that it can be done, so long as the right
person is found, can only be based on faith; I have nothing against
this, per se, but at least admit it and do not call other people's
logic flawed when it is merely common sense.
I remember a few years ago watching a rally; one driver flew off the
side of a mountain and landed on a tree further down, which prevented
the car rolling 200-300m to the bottom (certain death). Neither he nor
the navigator were hurt, and were rallying two weeks later. By your
logic, despite the several fatalities caused by speeding cars flying
off mountains, we should should not draw the conclusion that falling
off a mountain in a speeding car is a bad idea (since it is possible to
survive the crash).
Don't get me wrong, I'm all for intellectual independence, but claiming
that anyone who disagrees with the 4 points that you mentioned is on
the wrong track is difficult to place on a firm, factual basis. Not
that I personally have any opinion either way, to be honest.
By the way, calling something "establishment", thereby endowing it with
any number of unpleasant connotations, doesn't make it wrong.
Hope you don't take this the wrong way!
LEJ Brouwer
> Is it really fundamentally flawed to say that if something is attempted
> 100 times and it fails, then it can't be done?
Yes.
> It's exactly the logic
> that is used in science (namely, inductive, rather than deductive).
Well, that would seem to suggest that there may be a problem with
scientific method itself (or at least in the unobjective way in which
it is often applied), and I am sure one could dig out countless
examples of that throughout the history of science.
> Postulating, as you do, that it can be done, so long as the right
> person is found, can only be based on faith; I have nothing against
> this, per se, but at least admit it and do not call other people's
> logic flawed when it is merely common sense.
If you have seen a proof that quantum theory must be probabilistic,
then I would love to see it. Nelson's stochastic formulation of quantum
mechanics is classical and deterministic (i.e. it is 'common sense'),
but is simply not fashionable, so has not been investigated as much as
it deserves. The probabilistic interpretation of QM is certainly not
based on common sense. In fact it is pure nonsense which just happens
to give correct results.
> I remember a few years ago watching a rally; one driver flew off the
> side of a mountain and landed on a tree further down, which prevented
> the car rolling 200-300m to the bottom (certain death). Neither he nor
> the navigator were hurt, and were rallying two weeks later. By your
> logic, despite the several fatalities caused by speeding cars flying
> off mountains, we should should not draw the conclusion that falling
> off a mountain in a speeding car is a bad idea (since it is possible to
> survive the crash).
I am sorry, but I do not see the analogy. We all learn the
probabilistic interpretation of QM at university, usually to the
exclusion of any other possibilities, so it is hardly surprising that
few if any of the intellectual sheep in academia dare to stray so far
as to attempt to find a non-probabilistic interpretation. There are
reputations, and even possibly worldviews at stake after all.
> Don't get me wrong, I'm all for intellectual independence, but claiming
> that anyone who disagrees with the 4 points that you mentioned is on
> the wrong track is difficult to place on a firm, factual basis. Not
> that I personally have any opinion either way, to be honest.
Well, yes, it did take quite a bit of effort, as it happens. :)
> By the way, calling something "establishment", thereby endowing it with
> any number of unpleasant connotations, doesn't make it wrong.
I never claimed that it did. However it certainly is an 'establishment'
with all of the negative connotations that implies, and as it happens,
it is also almost certainly wrong on this point (I do not claim that it
is always wrong).
> Hope you don't take this the wrong way!
Certainly not. Thanks for your feedback!
Best wishes,
Sabbir.
Eugene Stefanovich
LEJ Brouwer wrote:
> If you have seen a proof that quantum theory must be probabilistic,
> then I would love to see it. Nelson's stochastic formulation of quantum
> mechanics is classical and deterministic (i.e. it is 'common sense'),
> but is simply not fashionable, so has not been investigated as much as
> it deserves. The probabilistic interpretation of QM is certainly not
> based on common sense. In fact it is pure nonsense which just happens
> to give correct results.
QM is probabilistic because nature is probabilistic.
Take a piece of radioactive substance and put a Geiger counter next to
it. Observe a sequence of clicks in the counter. This sequence of
clicks not only looks random, it IS random. There is no theory in
the world that can predict the timing of the clicks. Not because our
understanding of nuclear forces is imperfect yet. Even if we had
a complete quantum-mechanical description of atomic nuclei we wouldn't
be an inch closer to the prediction of the timing of the clicks.
Quantum mechanics just accepts this unpredictability as unavoidable
fact and concentrates on calculations of probabilities: i.e., the
probability of the nuclear decay at a given interval of time. That's
all QM can do. If you think there is a theory that can do better, then
this theory should be more fundamental than QM. I don't think such
a theory exists.
Eugene.
acl
Eugene Stefanovich wrote:
> LEJ Brouwer wrote:
>
> > If you have seen a proof that quantum theory must be probabilistic,
>
>
Well, but his point is that there may well be a non-probabilistic
theory; which is merely an assertion, like "there may be a large pink
bunny in orbit around Uranus", which is certainly a possibility.
Similarly, your statement is, again, an assertion of the same type (for
a deductivist): how do you know it's probabilistic?
For what it's worth, I don't see what the meaning of the word "is" in
the context of the sentence "nature is probabilistic" is, unless I take
several things for granted; but then I am implicitly talking about my
perception/description of nature (and no, I am not trying to be
philosophical here). Clearly, loads of people would violently disagree
with me on this, but there you go.
Charles Francis
<eug...@synopsys.com> writes
>QM is probabilistic because nature is probabilistic.
Classical probability theory describes situations in which every
parameter exists, but some are not known. Probabilistic results come
from different values taken by unknown parameters. We have a similar
situation in QM, but now the unknowns are not describable as parameters.
An experiment is described as a large configuration of particles
incorporating the measuring apparatus as well as the process being
measured. There are no relationships between particles bar those
generated by physical interaction and we do not know the precise
configuration of particle interactions. The configuration has been
partially determined by setting up the experimental apparatus, reducing
the possibilities to those with definite outcomes to the measurement. It
is impossible to determine every detail of the configuration since the
determination of each detail requires measurement, which in turn
requires a larger apparatus containing new unknowns in the configuration
of particles. Thus there is always a lack of determination of initial
conditions leading to randomness in the outcome, whether or not there is
a fundamental indeterminism in nature.
Regards
--
Charles Francis
Nick Maclaren
LEJ Brouwer <intuit...@yahoo.com> wrote:
>
>If you have seen a proof that quantum theory must be probabilistic,
>then I would love to see it. Nelson's stochastic formulation of quantum
>mechanics is classical and deterministic (i.e. it is 'common sense'),
>but is simply not fashionable, so has not been investigated as much as
>it deserves. The probabilistic interpretation of QM is certainly not
>based on common sense. In fact it is pure nonsense which just happens
>to give correct results.
Would you like to justify your last sentence? Exactly why are you so
certain that physics is deterministic?
For my amusement, can you provide a reasonably comprehensible
reference to Nelson's formulation - as a statistician, I find the
concept of a stochastic formulation that is purely deterministic
to be a trifle bizarre!
Regards,
Nick Maclaren.
Mike Helland
> acl wrote:
> > Is it really fundamentally flawed to say that if something is attempted
> > 100 times and it fails, then it can't be done?
>
> Yes.
>
> > It's exactly the logic
> > that is used in science (namely, inductive, rather than deductive).
>
> Well, that would seem to suggest that there may be a problem with
> scientific method itself (or at least in the unobjective way in which
> it is often applied), and I am sure one could dig out countless
> examples of that throughout the history of science.
Induction is not the method of science, but instead scientific
knowledge is conjectural knowledge refined through criticism (such as
being falsified by experiment).
In other words, nothing is ever proven true. We just hypothesize and
try to prove wrong. That's different from induction.
Nick Maclaren
acl <achilleas...@yahoo.co.uk> wrote:
>Eugene Stefanovich wrote:
>> LEJ Brouwer wrote:
>>
>> > If you have seen a proof that quantum theory must be probabilistic,
>>
>> QM is probabilistic because nature is probabilistic.
>
>Well, but his point is that there may well be a non-probabilistic
>theory; which is merely an assertion, like "there may be a large pink
>bunny in orbit around Uranus", which is certainly a possibility.
>Similarly, your statement is, again, an assertion of the same type (for
>a deductivist): how do you know it's probabilistic?
Right. My mathematics is not good enough to tie all of this together,
and I don't know of any first-class mathematicians who have done so,
but the following is effectively common knowledge:
If you can control and observe only some parameters of a sufficiently
large, sufficiently complex system, the behaviour of the ones that
you can control and observe will be indistinguishable from that of
the parameters of a probabilistic system.
I have looked at this in the context of pseudo-random numbers, and can
give some bounds on 'sufficiently large' and some indications of what
is meant by 'sufficiently complex' (a chaotic system will do, but is
not essential). Unfortunately, I have been unable to get anywhere very
interesting.
Einstein (and Brouwer) were being religious in assuming such a system,
but were NOT being unscientific. It was then, and is now, a possibility.
As you point out, Stefanovich is similarly religious in assuming the
converse, but that is equally possible.
>For what it's worth, I don't see what the meaning of the word "is" in
>the context of the sentence "nature is probabilistic" is, unless I take
>several things for granted; ...
Ah! A true philosopher! Yes, I agree. When we have decided that, we
can move on to 'probablistic', but life is too short to reach 'nature'.
Regards,
Nick Maclaren.
cma...@yahoo.com
> LEJ Brouwer wrote:
>
> > If you have seen a proof that quantum theory must be probabilistic,
> > mechanics is classical and deterministic (i.e. it is 'common sense'),
> > but is simply not fashionable, so has not been investigated as much as
> > it deserves. The probabilistic interpretation of QM is certainly not
> > based on common sense. In fact it is pure nonsense which just happens
> > to give correct results.
>
> it. Observe a sequence of clicks in the counter. This sequence of
> clicks not only looks random, it IS random. There is no theory in
> the world that can predict the timing of the clicks. Not because our
> understanding of nuclear forces is imperfect yet. Even if we had
> a complete quantum-mechanical description of atomic nuclei we wouldn't
> be an inch closer to the prediction of the timing of the clicks.
>
> Quantum mechanics just accepts this unpredictability as unavoidable
> fact and concentrates on calculations of probabilities: i.e., the
> probability of the nuclear decay at a given interval of time. That's
> all QM can do. If you think there is a theory that can do better, then
> this theory should be more fundamental than QM. I don't think such
> a theory exists.
>
> Eugene.
Great! So the PERFECT random number generator does exist after all.
Please inform all cryptographers, they've been dreaming about it for so
long.
Chris
acl
We seem to be diametrically opposed in our views of what science is
(since you find an inductive approach flawed). Now, since lots of
people here seem to quote various authorities, let me join in the fun.
I could not agree more with the following quote:
"I have no reason to believe that the human intellect is able to weave
a system of physics out of its own resources without experimental
labour. Whenever the attempt has been made it has resulted in an
unnatural and self-contradictory mass of rubbish."
James Clerk Maxwell
(I especially like the last sentence). Of course, anybody who believes
otherwise is free to do so, and is even to be encouraged. Diversity is
always a good thing.
All the best
Cl.Massé
1121118187.4...@g44g2000cwa.googlegroups.com...
> Is it really fundamentally flawed to say that if something is attempted
> 100 times and it fails, then it can't be done? It's exactly the logic
> that is used in science (namely, inductive, rather than deductive).
This logic is used for building a theory, which have then to be verified by
experiment. But it often happens that the theory is falsified by an
experimental result. It is the fate of all theory.
Now, saying that only a probalistic theory can describe Nature at the
quantum level, because every other attempt failed, is by itself a
fully-fledged theory, awaiting to be falsified.
--
~~~~ clmasse on free F-country
Liberty, Equality, Profitability.
cma...@yahoo.com
Sabbir can speak for himself, but my reaction to this quote is that
induction and deduction must work in tandem in order to converge
towards an increasingly predictive theory. I guess everyone realizes
that, but when it comes to particle physics, all of a sudden, induction
imposes its truths on deduction. I would say that any view that
purports that "events can happen without any cause" ultimately
erradicates the deduction process to some degree. What is deduction if
not a reflection on causes and effects?
Chris
Marcel LeBel
>>Well, but his point is that there may well be a non-probabilistic
>>theory; which is merely an assertion, like "there may be a large pink
>>bunny in orbit around Uranus", which is certainly a possibility.
>>Similarly, your statement is, again, an assertion of the same type (for
>>a deductivist): how do you know it's probabilistic?
>
>
opposite of probability or, certainty. It is either a certainty or/or a
probability. Here is an example. If you drop an object, is the fall a
certainty? No. You may stop the falling object as can any other
influence also affect it. Conclusion: the gravitational fall IS a
probability. It is a probability of motion that is higher in one
direction (toward the ground). The object's weight in your hand is the
-weight- of that higher probability, still present.
By this example, you may understand that there are most likely, very few
certainties in this universe. A certainty would have to be a spontaneous
event which cannot be in any way stopped. The passage of time (the
universality, not its rate value) is the only certainty in that we don't
have the choice. the absence of choice is a truth.
le...@muontailpig.com remove particle
acl
probabilistic description is necessary, correct, or incorrect. Neither
did I claim the opposite: nobody knows, and all we can do is come up
with educated guesses which we then compare to experiment.
All I was saying was that if such a thing happened in everyday life,
you'd conclude that it can't be done. Obviously, it doesn't (and can't)
constitute a proof that it can't be done.
Of course, the fact that we don't really know allows everybody to have
his or her own opinion.
Uncle Al
The order of digits of pi are perfectly random by any and all tests of
randomness (aside from being pi). Both radioactive decay and shot
noise are perfectly random. Given an arbitrarily long string of prior
putput, predicting the next bit with better than random chance cannot
be done. (In the case of pi one can obviously use pi generator
functions and last digit generators, working not from the byte string
but from prior global knowledge.)
Economics works ia similar fashion. One cannot fit prior data and
then use the model to extrapolate to an accurate prediction of future
behavior. Ditto future climate or research discoveries. Storing
radioactive waste for "10,000 years" is a bunch of execrable political
hooey. If they were at all serious about it the things would be in
Hastelloy C-2000 containment not steel.
Nick Maclaren
Charles Francis <cha...@clef.demon.co.uk> wrote:
>In message <42DFF685...@synopsys.com>, Eugene Stefanovich
><eug...@synopsys.com> writes
>>QM is probabilistic because nature is probabilistic.
>
>Classical probability theory describes situations in which every
>parameter exists, but some are not known. Probabilistic results come
Er, no.
Real probability theory (as distinct from the gross simplification
that sometimes gets lumped in with discrete mathematics) is about
measures over Borel sets. Individual measurements are genuinely
random observations from a distribution, and the theory is about
the distribution. The choice of which element of the Borel set is
observed in a particular case is not a hidden parameter.
Regards,
Nick Maclaren.
acl
> Induction is not the method of science, but instead scientific
> knowledge is conjectural knowledge refined through criticism (such as
> being falsified by experiment).
>
> In other words, nothing is ever proven true. We just hypothesize and
> try to prove wrong. That's different from induction.
>
in the morning and, just because he/she felt like it, conjectured that
QM is a good way to describe small-scale phenomena. Rather, a mixture
of induction and deduction is used, obviously. As well as analogies,
see, for example, "An Undulatory Theory of the Mechanics of Atoms and
Molecules", Phys. Rev. 28, 1049--1070 (Schrodinger, 1926). So, to
assert that "we just hypothesize and try to prove wrong" is incorrect.
acl
You are absolutely right: observing only a few degrees of freedom in
large system usually results in them appearing to be random. This,
after all, is the reason statistical mechanics works (fluctuations
about equilibrium values of various quantities and so on). The use of
stochastic differential equations to describe a brownian particle is a
simple example: the particle's motion could, in principle, be
calculated from the dynamics of the microscopic particles that collide
with it (assumed deterministic but with unknown initial conditions and
so on), but, if we somehow integrate them out, a stochastic
differential equation results. There is a lot of work on this kind of
thing (such as a heavy particle coupled to lots of quantum harmonic
oscillators, from which a Fokker-Planck equation is obtained for the
heavy particle).
Now, the question is, why does this work? Why can I ignore the 10^23
molecules in a box full of gas and, to a high degree of accuracy, deal
only with pressure, temp and vol? (the answer, probably, is symmetry,
which makes applicable some sort of central limit theorem).
Eugene Stefanovich
Yes, why not?
I don't know any cryptographer, but if you have friends in this
business, please tell them about that. They may like it.
There are experimental works studying the randomness of quantum
events. One example is physics/0304013. I haven't made a
literature search on this subject, but I am sure there are more papers
like this one.
Eugene.
LEJ Brouwer
> Sabbir,
> We seem to be diametrically opposed in our views of what science is
> (since you find an inductive approach flawed).
That's not entirely true. I merely think an inductive approach can be
quite efficient. Paradigm changes (which is what we really need right
now) can require tremendous creativity and intuition, and perhaps even
'leaps of faith' to have the courage to try out ideas which others may
at first may think to be crazy. An inductive approach will typically
lead to incremental changes, whereas as crazy ideas will either turn
out to be wrong, or may overturn generally established conceptions.
Both of these are fundamental modes of human thought, and have a role
to play. But as I said, we are stuck in a rut right now (basis of
quantum theory, quantum theory of gravity, cosmological constant, dark
energy/dark matter), and what we need is a major paradigm change. While
it is all very well adding scalar fields all over the place and
tweaking them by hand (which turns out to be all to easy judging by the
number of papers spewing forth) to conveniently fit aspects of
experimental data, it would be nice to have a theory which had some
kind of compelling physical motivation.
> Now, since lots of
> people here seem to quote various authorities, let me join in the fun.
> I could not agree more with the following quote:
>
> "I have no reason to believe that the human intellect is able to weave
> a system of physics out of its own resources without experimental
> labour. Whenever the attempt has been made it has resulted in an
> unnatural and self-contradictory mass of rubbish."
> James Clerk Maxwell
Well, I was not advocating ignoring experimental results, so I am not
sure whether this is particularly relevant.
> (I especially like the last sentence). Of course, anybody who believes
> otherwise is free to do so, and is even to be encouraged. Diversity is
> always a good thing.
> All the best
Thanks,
Sabbir.
LEJ Brouwer
> >
> >If you have seen a proof that quantum theory must be probabilistic,
> >then I would love to see it. Nelson's stochastic formulation of quantum
> >mechanics is classical and deterministic (i.e. it is 'common sense'),
> >but is simply not fashionable, so has not been investigated as much as
> >it deserves. The probabilistic interpretation of QM is certainly not
> >based on common sense. In fact it is pure nonsense which just happens
> >to give correct results.
>
> certain that physics is deterministic?
I just gave a presentation summarising why I believe this to be the
case at the Einstein century conference in Paris. Basically, if we
assume the vacuum is a relativistic fluid (actually it is sufficient to
start with a relativistic space-filling medium), then it is possible to
rigorously derive stochastic quantum mechanics (and also a stochastic
formulation of both electrodynamics and GR, as it happens). When I have
completed the formal write-up of these results I will submit the
preprint to the arxiv (it is almost complete now). I can send you a
copy of the conference presentation if you are interested.
> For my amusement, can you provide a reasonably comprehensible
> reference to Nelson's formulation - as a statistician, I find the
> concept of a stochastic formulation that is purely deterministic
> to be a trifle bizarre!
I think that it is conceptually quite simple - any fluid undergoing a
*conservative* diffusion process (which is not quite the same as
Brownian motion as there is no dissipation of energy due to friction or
which excite internal degrees of freedom of the fluid particles), will
have the evolution of its density distribution governed by quantum
mechanics. The most relevant examples of conservative diffusions are
pointlike particles in a Coulomb potential or gravitational field,
though it also works for a much more general class of potentials (see
the paper by Eric Carlen for details). In very simple terms, if you
have a lot of particles all attracting each other, then the motion of
an individual particle, although deterministic, will be extraordinarily
complicated - to the extent that only a stochastic description of its
motion can in practice be made. This is basically exactly what Charles
Francis said in his earlier message.
> Regards,
> Nick Maclaren.
Best wishes,
Sabbir.
acl
(theorems) of a set of axioms. So, I can't see how it's at all related
to causes and effects in a physical sense, unless you call the axioms
the cause and the theorems the effects.
It seems we use the word deduction to mean different things.
Nick Maclaren
acl <achilleas...@yahoo.co.uk> wrote:
>Just to make something clear, at no point did I claim that a
>probabilistic description is necessary, correct, or incorrect. Neither
>did I claim the opposite: nobody knows, and all we can do is come up
>with educated guesses which we then compare to experiment.
Agreed, except perhaps in the matter of experiment (see below).
>Of course, the fact that we don't really know allows everybody to have
>his or her own opinion.
I believe that it is provably impossible to distinguish the two by
experiment. If I am correct, opinions about which is correct are
religion, not science. However, I cannot provide proof of my belief,
nor indeed much more evidence than hand-waving (except in a few
specialised cases, such as I described).
Of course, options about whether a subset of physics is better
modelled probabilistically or deterministically remain the realm
of science.
Regards,
Nick Maclaren.
Paul Danaher
> cma...@yahoo.com wrote:
..
> Economics works ia similar fashion. One cannot fit prior data and
> then use the model to extrapolate to an accurate prediction of future
> behavior. Ditto future climate or research discoveries. Storing
> radioactive waste for "10,000 years" is a bunch of execrable political
> hooey. If they were at all serious about it the things would be in
> Hastelloy C-2000 containment not steel.
The *whole point of econometrics* is to find models which allow you "to fit
prior data and use the model to extrapolate". I don't opinionate about
physics, so please don't badmouth my troubled and struggling neoscience.
cma...@yahoo.com
That's right, there is no reason not to view axioms as causes of
theorems, and that is partly what I meant.
Deduction is indeed the act of working out the consequences of a set of
axioms. But axioms are not limited to postulates as we normally think
of them, they also include the boundary and/or initial conditions of a
system. When we start reasoning about an atom in a certain state, we
are adding the axioms regarding that state to the set of premises, and
then we work out the consequences.
Chris
Torbjorn Larsson
experiment. If I am correct, opinions about which is correct are
religion, not science. "
I think this is correct. Someone pointed out a while back that the
different QM interpretations has the same property.
Cl.Massé
> Now, the question is, why does this work? Why can I ignore the 10^23
> molecules in a box full of gas and, to a high degree of accuracy, deal
> only with pressure, temp and vol? (the answer, probably, is symmetry,
> which makes applicable some sort of central limit theorem).
The answer is in the textbooks on statistical thermodynamics. The laws of
macroscopic thermodynamics are derived through theorems of probabilities.
Arnold Neumaier
>
> Take a piece of radioactive substance and put a Geiger counter next to
> it. Observe a sequence of clicks in the counter. This sequence of
> clicks not only looks random, it IS random.
What is the difference? How can you distinguish experimentally between
the two?
Arnold Neumaier
LEJ Brouwer
I think it is unlikely that a classical deterministic description of
quantum mechanics would have the same physical predictions as a purely
probabilistic one. For example, relativistic stochastic mechanics
appears to introduce small stochastic corrections of order hbar^2 to
the Klein-Gordon equation, as well as further corrections in the
presence of a curved spacetime. Moreover, measurements are in principle
possible at the Planck scale in the classical case (albeit probably
rather difficult in practice) - e.g. motion of individual diffusing
particles, which would have no counterpart in the probabilistic
framework. The latter can only describe quantities depending on
averages over many diffusing particles (which is in fact precisely why
the observations are probabilistic).
I see no reason to believe that physical observations are fundamentally
probabilistic in nature when a perfectly natural classical explanation
is possible.
- Sabbir.
Nick Maclaren
In article <1122369243.0...@g47g2000cwa.googlegroups.com>, "LEJ Brouwer" <intuit...@yahoo.com> writes:
|> Torbjorn Larsson wrote:
|> > "I believe that it is provably impossible to distinguish the two by
|> > experiment. If I am correct, opinions about which is correct are
|> > religion, not science. "
|> >
|> > I think this is correct. Someone pointed out a while back that the
|> > different QM interpretations has the same property.
|>
|> I think it is unlikely that a classical deterministic description of
|> quantum mechanics would have the same physical predictions as a purely
The term "likely" when applied to hypotheses about physics is a
matter of personal judgement, not anything absolute. The real
question is whether it is possible.
|> I see no reason to believe that physical observations are fundamentally
|> probabilistic in nature when a perfectly natural classical explanation
|> is possible.
In what way does that differ from the following, other than being
duals?
I see no reason to believe that physical observations are
fundamentally deterministic in nature when a perfectly natural
probabilistic explanation is possible.
Regards,
Nick Maclaren.
Eugene Stefanovich
I think you meant how to distinguish random from not random?
In my view there are two kinds of randomness. One kind is pure
statistical, i.e., the absence of correlations. I don't know
much about mathematical statistics, so I refer you to physics/0304013
and references cited there.
The other kind is the fact that today's theory has no capacity
to predict the sequence of the clicks. Even remotely.
Even if we had a full quantum mechanical description of a radioactive
nucleus, with the full energy spectrum and wave functions, we
couldn't tell (even approximately) at what time the nucleus is supposed
to decay. All we can do is to calculate the lifetime. If the lifetime
of the nucleus is one year, then the uncertainty of our prediction of
the decay time is roughly one year.
Eugene.
Torbjorn Larsson
interpretations of standard QM. These gives the same predictions of
factual experiments (they are mathematically equivalent) - otherwise
they wouldn't be interpretations.
Nick are arguing that deterministic or probability foundation is
indistinguishable by experiment today. I supported him with the
observation that you cannot use QM interpretations to help you
distinguish. To choose a particular QM interpretation today is a matter
of faith.
I don't think attempts to modify QM is taken seriously today since
standard QM is the simplest such theory one can have (linear)
consistent with observations. An interesting generalisation and
interpretation is consistent histories.
cma...@yahoo.com
In a previous thread I wrote that cryptographers would be surprised
about the existence of such a perfect random number generator. Actually
they are using techniques based on these facts. However, this
randomness of lifetimes in no way constitutes an argument in favor of a
probabilistic nature. I won't deliberate much on this, as in his
message of July 23, Charles Francis expressed views that are similar to
mine.
If all things are being equal, and we observe two nuclei with different
lifetimes, then I would admit that nature is quite certainly
probabilistic. But that's where this theory is so specious: no-one that
I know of can guarantee that a pair of nuclei (along with their
neigborhood) are exactly equal in state. The "all things being equal"
part of the contract is nearly impossible to meet.
Chris
Nick Maclaren
Eugene Stefanovich <eug...@synopsys.com> wrote:
>Arnold Neumaier wrote:
>>
>>>Take a piece of radioactive substance and put a Geiger counter next to
>>>it. Observe a sequence of clicks in the counter. This sequence of
>>>clicks not only looks random, it IS random.
>>
>> What is the difference? How can you distinguish experimentally between
>> the two?
>
>I think you meant how to distinguish random from not random?
>
>In my view there are two kinds of randomness. One kind is pure
>statistical, i.e., the absence of correlations. I don't know
>much about mathematical statistics, so I refer you to physics/0304013
>and references cited there.
Well, I know something :-) Here, you are using the term "random"
to mean "independent" in a probabilistic sense - it is a common
use of the word in English. It is not the relevant meaning here.
>The other kind is the fact that today's theory has no capacity
>to predict the sequence of the clicks. Even remotely.
>Even if we had a full quantum mechanical description of a radioactive
>nucleus, with the full energy spectrum and wave functions, we
>couldn't tell (even approximately) at what time the nucleus is supposed
>to decay. All we can do is to calculate the lifetime. If the lifetime
>of the nucleus is one year, then the uncertainty of our prediction of
>the decay time is roughly one year.
Well, you're a bit closer. But your last sentence is pretty fair
gibberish, and the expression "is supposed to" is worse.
The distinction being made here is between two models:
A) Where there are a certain set of physical parameters, and some
events that occur with probabilities based on those parameters. And,
yes, this is true probability in the measure theoretic sense (don't
bother to chase that term up). There is thus NO CONCEPT of predicting
which of the possible events WILL occur except as constrained by the
probability distributions. Mathematically, it is the distributions
(actually Lebesgue measures over Borel sets) that are the primitive
values for doing calculations on the theory.
B) Where there are a certain set of visible physical parameters,
and another set of invisible ones. You can observe and change only
the visible ones, though you may be able to deduce the existence of
the invisible ones in very simple cases. However, the model here is
when the case is NOT simple, and the invisible parameters are
behaving chaotically, so that (try as we may) we can't get the
visible ones to repeat previous behaviour exactly.
I and several other people believe that it is provably impossible to
distinguish these two models by experiment.
Is that any clearer?
Regards,
Nick Maclaren.
Arnold Neumaier
>
>
> Arnold Neumaier wrote:
>
>> Eugene Stefanovich wrote:
>>
>>> Take a piece of radioactive substance and put a Geiger counter next to
>>> it. Observe a sequence of clicks in the counter. This sequence of
>>> clicks not only looks random, it IS random.
>>
>>
>>
>> What is the difference? How can you distinguish experimentally between
>> the two?
>
> I think you meant how to distinguish random from not random?
I inquired about the meaning of your statement
''This sequence of clicks not only looks random, it IS random.''
It contains two concepts of 'looking random' and 'BEING random',
applicable to events in reality. I have not the slightest idea how
to distinguish the two.
> In my view there are two kinds of randomness. One kind is pure
> statistical, i.e., the absence of correlations. I don't know
> much about mathematical statistics, so I refer you to physics/0304013
> and references cited there.
>
> The other kind is the fact that today's theory has no capacity
> to predict the sequence of the clicks. Even remotely.
So you'd say, BEING random is a time dependent property?
4000 years ago almost everything WAS random in this sense.
And today, weather two weeks ahead still IS random.
4000 years in the future, even fewer things will BE random,
if our present culture continues to develop like it did in the past.
I don't think this is a good way to use the notion of 'random'
in physics.
> Even if we had a full quantum mechanical description of a radioactive
> nucleus, with the full energy spectrum and wave functions, we
> couldn't tell (even approximately) at what time the nucleus is supposed
> to decay. All we can do is to calculate the lifetime. If the lifetime
> of the nucleus is one year, then the uncertainty of our prediction of
> the decay time is roughly one year.
Of a good random generator one wants to know the distribution
of numbers produced. While radioactive decay is approximately Poisson,
I am sure that any good pseudorandom Poisson generator will
be far more reliable than one that employs instead a Geiger counter.
Arnold Neumaier
Eugene Stefanovich
> The distinction being made here is between two models:
>
> A) Where there are a certain set of physical parameters, and some
> events that occur with probabilities based on those parameters. And,
> yes, this is true probability in the measure theoretic sense (don't
> bother to chase that term up). There is thus NO CONCEPT of predicting
> which of the possible events WILL occur except as constrained by the
> probability distributions. Mathematically, it is the distributions
> (actually Lebesgue measures over Borel sets) that are the primitive
> values for doing calculations on the theory.
Can I translate that as "quantum mechanics"?
>
> B) Where there are a certain set of visible physical parameters,
> and another set of invisible ones. You can observe and change only
> the visible ones, though you may be able to deduce the existence of
> the invisible ones in very simple cases. However, the model here is
> when the case is NOT simple, and the invisible parameters are
> behaving chaotically, so that (try as we may) we can't get the
> visible ones to repeat previous behaviour exactly.
Can I translate that as "hidden variable theory"?
> I and several other people believe that it is provably impossible to
> distinguish these two models by experiment.
There are hundreds (maybe thousands) of papers discussing the
possibilities of distinguishing QM and HVT in experiment.
EPR experiment and all that. It seems to me that the general consensus
is that QM is in full agreement with experiment, and HVT does not
contradict experiment as long as hidden variables
are non-local (whatever it means). I prefer to stick with QM due to
its inherent mathematical/physical beauty.
Eugene.
Eugene Stefanovich
> If all things are being equal, and we observe two nuclei with different
> lifetimes, then I would admit that nature is quite certainly
> probabilistic. But that's where this theory is so specious: no-one that
> I know of can guarantee that a pair of nuclei (along with their
> neigborhood) are exactly equal in state. The "all things being equal"
> part of the contract is nearly impossible to meet.
If you have just one radioactive nucleus you cannot even speak about
it lifetime. You can observe its decay and see that it has decayed,
say, 1 hour after it was created. From this you cannot make a prediction
of how long similar nuclei will live. They may live 0.1 ns or 1000000
years.
You need to observe a huge number of nuclear decays, collect
statistics, and only after that you can determine (experimentally)
the lifetime of nuclei of this type. The lifetime (just as the
wave function, in general) does not describe one particular
nucleus. It describes a statistical ensemble of similarly prepared
nuclei.
Eugene.
Eugene Stefanovich
> I don't think attempts to modify QM is taken seriously today since
> standard QM is the simplest such theory one can have (linear)
> consistent with observations. An interesting generalisation and
> interpretation is consistent histories.
Experimentally, QM has been tested more than any other theory.
It always passed the test. Theoretically, the foundations of QM
look unshakable. They are given by postulates of quantum logic.
There are many books on this subject. I prefer C. Piron's
"Foundations of Quantum Physics", (W. A. Benjamin, Reading, 1976).
You can also find the summary of quantum logic arguments in chapter 4
of physics/0504062
Personally, I do not expect any viable generalizations
(e.g., non-linear) of quantum mechanics any time soon.
Eugene.
Nick Maclaren
Eugene Stefanovich <eug...@synopsys.com> wrote:
>Nick Maclaren wrote:
>
>> The distinction being made here is between two models:
>>
>> A) Where there are a certain set of physical parameters, and some
>> events that occur with probabilities based on those parameters. And,
>> yes, this is true probability in the measure theoretic sense (don't
>> bother to chase that term up). There is thus NO CONCEPT of predicting
>> which of the possible events WILL occur except as constrained by the
>> probability distributions. Mathematically, it is the distributions
>> (actually Lebesgue measures over Borel sets) that are the primitive
>> values for doing calculations on the theory.
>
>Can I translate that as "quantum mechanics"?
No.
Regards,
Nick Maclaren.
Eugene Stefanovich
"Arnold Neumaier" <Arnold....@univie.ac.at> wrote in message
news:42E8A4B7...@univie.ac.at...
> > The other kind is the fact that today's theory has no capacity
> > to predict the sequence of the clicks. Even remotely.
>
> So you'd say, BEING random is a time dependent property?
> 4000 years ago almost everything WAS random in this sense.
> And today, weather two weeks ahead still IS random.
> 4000 years in the future, even fewer things will BE random,
> if our present culture continues to develop like it did in the past.
>
>
> I don't think this is a good way to use the notion of 'random'
> in physics.
OK, I see your point. The word "unpredictable" suits better here.
Eugene.
cma...@yahoo.com
You seem to be of good faith, but you are more or less playing with
words here. Of course, I know the usual definition of "lifetime".
Replace it with "decay time" if you will, or simply apply the word
"lifetime" to a set of 1 nucleus. Sets can be singletons.
The real question is: Is nature deterministic or not? You seem to
adhere to the view that it is not deterministic. But let's confirm this
with this question: Given a pair of perfectly identical nuclei having
EXACTLY THE SAME STATE {to every imaginable and inimaginable detail),
and with similar neighborhoods. Does it seem plausible to you that they
will take different amounts of time to decay?
Chris
Eugene Stefanovich
> The real question is: Is nature deterministic or not? You seem to
> adhere to the view that it is not deterministic. But let's confirm this
> with this question: Given a pair of perfectly identical nuclei having
> EXACTLY THE SAME STATE {to every imaginable and inimaginable detail),
> and with similar neighborhoods. Does it seem plausible to you that they
> will take different amounts of time to decay?
I cannot say about "unimaginable detail", because I cannot imagine it.
But if two nuclei are prepared in exactly (to every imaginable detail)
the same states, they will surely take different amounts of time to
decay. The nature is not deterministic. This is the main lesson of
quantum mechanics.
Of course, one can hope that this is not true, and that there are
some yet unknown hidden parameters that someday will allow us
to return to the classical deterministic picture; some "alarm clock"
hidden within the nucleus that tells the nucleus at what exact time
to disintegrate. I don't share these hopes. Though I don't have a proof
that such hopes are groundless.
Eugene.
Torbjorn Larsson
It always passed the test. Theoretically, the foundations of QM
look unshakable."
Yes.
"They are given by postulates of quantum logic.
There are many books on this subject. I prefer C. Piron's
"Foundations of Quantum Physics", (W. A. Benjamin, Reading, 1976).
You can also find the summary of quantum logic arguments in chapter 4
of physics/0504062."
There are several interpretations of QM theory. I don't know about this
one, so thanks for the pointers.
"Personally, I do not expect any viable generalizations
(e.g., non-linear) of quantum mechanics any time soon."
Me neither. To call consistent histories a generalisation is not a very
interesting statement. It adds 1 or 2 axioms, but gives the same
results as I understand it. (I haven't studied it.) The difference is
in the interpretation.
Cl.Massé
> > Take a piece of radioactive substance and put a Geiger counter next to
> > it. Observe a sequence of clicks in the counter. This sequence of
> > clicks not only looks random, it IS random.
"Arnold Neumaier" <Arnold....@univie.ac.at> a écrit dans le message de
news: 42E5F1F9...@univie.ac.at...
> What is the difference? How can you distinguish experimentally between
> the two?
We can easily distinguish it experimentally, with statistical tests, but
it isn't really the issue.
If we take the hypothesis that the times of the clicks depends on the
state of the whole Universe, we can have true randomness.
Looks like only a speculative hypothesis? Read further.
The phenomenon of quantum entanglement have been observed
experimentally, while rejecting the existence a local hidden variables,
and with no information traveling faster than light. Now, all the
particles where interacting with each other at the Big Bang, they are
therefore all correlated. The measure of any property of any particle
is then correlated with the whole Universe. But for that to be
compatible with relativity, that is no information comming from
elsewhere, the outcome of a measurement *must* be truly random,
otherwise the non randomness would be information comming from
elsewhere. The only other possibility is that there be only one outcome
possible, and therefore no correlation at all.
Even if such a correlation exist, it is impossible to predict any
outcome, since it implies the knowledge of the state of the Universe "at
the time" of the measurment. The illusion of randomness would thus be
perfect.
The possible correlation with other part of the Universe is beforehand
excluded in any physical reasoning, falsly on relativity ground. It is
a hidden assumption. It is universaly assumed that the physical laws
must be local. Indeed, it is one of the few assumptions that remains to
be challenged. The hidden variables would exist, but would be
non-local.
Special relativity isn't basically local, since it postulates the sames
laws even for spaces very far apart. Yet we could think that it is
basically non-local, and the causality principle is derived, and not
postulated, from other laws of physics still to be discovered.
The contrary to locality is globality, and there are global concepts,
like topological solitons, that could be used to model the particles.
I.Vecchi
..
>
> The real question is: Is nature deterministic or not? You seem to
> adhere to the view that it is not deterministic. But let's confirm this
> with this question: Given a pair of perfectly identical nuclei having
> EXACTLY THE SAME STATE {to every imaginable and inimaginable detail),
> and with similar neighborhoods. Does it seem plausible to you that they
> will take different amounts of time to decay?
If one agrees that "the quantum state is just an expectation catalog
.. its purpose is to make predictions about possible measurement
results a specific observer does not know yet" ([1]), then obviously
yes.
However in order to accept the above one has to give up deeply
ingrained metaphysical assumptions (aka superstitions) about
"objective" reality.
IV
[1] Thomas Jennewein, Gregor Weihs, Jian-Wei Pan, Anton Zeilinger
"Reply to Ryff's comment ..." quant-ph/0303104
cma...@yahoo.com
> cma...@yahoo.com wrote:
>
> > The real question is: Is nature deterministic or not? You seem to
> > adhere to the view that it is not deterministic. But let's confirm this
> > with this question: Given a pair of perfectly identical nuclei having
> > EXACTLY THE SAME STATE {to every imaginable and inimaginable detail),
> > and with similar neighborhoods. Does it seem plausible to you that they
> > will take different amounts of time to decay?
>
> I cannot say about "unimaginable detail", because I cannot imagine it.
I know that a butterfly flapping its wings in the amazonian jungle
might affect my life in a big way. That's just one thing I could
imagine, but I don't need to imagine all wing flapping things on earth
in order to conclude that other inimaginable wing flapping things might
also affect my life. Just because I've always worn sunshades doesn't
mean the world is black and white, it's just that I don't have enough
imagination about colors. The same goes for everything else; it's
enough for me to know that my imagination is limited to keep me out of
the trouble of writing stuff that might very well be laughed at two
centuries from now.
> But if two nuclei are prepared in exactly (to every imaginable detail)
> the same states, they will surely take different amounts of time to
> decay. The nature is not deterministic. This is the main lesson of
> quantum mechanics.
>
> Of course, one can hope that this is not true, and that there are
> some yet unknown hidden parameters that someday will allow us
> to return to the classical deterministic picture; some "alarm clock"
> hidden within the nucleus that tells the nucleus at what exact time
> to disintegrate. I don't share these hopes. Though I don't have a proof
> that such hopes are groundless.
>
> Eugene.
Fair enough, that's a far cry from the initial claim that "QM is
probabilistic because nature is probabilistic", but it's much better.
Chris
Arnold Neumaier
> Eugene Stefanovich wrote:
>
>>>Take a piece of radioactive substance and put a Geiger counter next to
>>>it. Observe a sequence of clicks in the counter. This sequence of
>>>clicks not only looks random, it IS random.
>
> "Arnold Neumaier" <Arnold....@univie.ac.at> a écrit dans le message de
> news: 42E5F1F9...@univie.ac.at...
>
>>What is the difference? How can you distinguish experimentally between
>>the two?
>
> We can easily distinguish it experimentally, with statistical tests, but
> it isn't really the issue.
No. There is no statistical test for randomness, only for
'uniformly random in [a,b]',
'N(mu,sigma^2)-distributed',
etc.. Randomness without specifying a narrow class of distributions
is not testable.
Arnold Neumaier
Nick Maclaren
Arnold Neumaier <Arnold....@univie.ac.at> wrote:
>
>No. There is no statistical test for randomness, only for
> 'uniformly random in [a,b]',
> 'N(mu,sigma^2)-distributed',
>etc.. Randomness without specifying a narrow class of distributions
>is not testable.
Practically, yes - but, strictly, no :-)
There are 'universal' tests, and some have been known for 70+ years.
Computer scientists discovered them a couple of decades back, and
announced them as new with a flourish of trumpets. I could probably
think of half a dozen mathematically distinct ones if I put my mind
to it.
They ALL have the property that they are computationally infeasible.
As can be proven rigorously, the power of a test is greater the more
restrictive the null hypothesis is - and the null hypothesis of just
independence is very weak indeed. They are of theoretical interest
only, for that reason.
Regards,
Nick Maclaren.
Cl.Massé
> No. There is no statistical test for randomness, only for
> 'uniformly random in [a,b]',
> 'N(mu,sigma^2)-distributed',
> etc.. Randomness without specifying a narrow class of distributions
> is not testable.
The distribution, as well as every correlation, is given by the quantum
calculus. Randomness is nothing more and nothing less than the testable
compliance to those laws.
Arnold Neumaier
> "Arnold Neumaier" <Arnold....@univie.ac.at> a écrit dans le message de
> news: 42EC9DD0...@univie.ac.at...
>
>
>>No. There is no statistical test for randomness, only for
>> 'uniformly random in [a,b]',
>> 'N(mu,sigma^2)-distributed',
>>etc.. Randomness without specifying a narrow class of distributions
>>is not testable.
>
>
> The distribution, as well as every correlation, is given by the quantum
> calculus.
The quantum calculus requires a closed system and a complete knowledge
of the state. Both is not realizable in Nature.
Arnold Neumaier
Arnold Neumaier
> In article <42EC9DD0...@univie.ac.at>,
> Arnold Neumaier <Arnold....@univie.ac.at> wrote:
>
>>No. There is no statistical test for randomness, only for
>> 'uniformly random in [a,b]',
>> 'N(mu,sigma^2)-distributed',
>>etc.. Randomness without specifying a narrow class of distributions
>>is not testable.
>
>
> Practically, yes - but, strictly, no :-)
What could this possibly mean? Randomness is not well-defined
mathematically. What _is_ defined is a random variable with a specific
distribution. But since random variables with a delta distirbution take
only a single value, being a large (or even infinite) sample of
independent realizations of a random variable is not a suitable
definition of 'random'.
There is also an information theoretic definition of randomness,
namely nonpredictability by an automaton. But this cannot be tested with
finite samples of finite precision.
> There are 'universal' tests, and some have been known for 70+ years.
> Computer scientists discovered them a couple of decades back, and
> announced them as new with a flourish of trumpets. I could probably
> think of half a dozen mathematically distinct ones if I put my mind
> to it.
Please give a definition of 'random' that is reasonably well accepted,
and then an universal test for it.
Arnold Neumaier
Nick Maclaren
In article <42EF416A...@univie.ac.at>,
Arnold Neumaier <Arnold....@univie.ac.at> writes:
|> >
|> > Practically, yes - but, strictly, no :-)
|>
|> What could this possibly mean? Randomness is not well-defined
|> mathematically. What _is_ defined is a random variable with a specific
|> distribution. But since random variables with a delta distirbution take
|> only a single value, being a large (or even infinite) sample of
|> independent realizations of a random variable is not a suitable
|> definition of 'random'.
No, that is too simplistic. Statisticians aren't so limited.
|> There is also an information theoretic definition of randomness,
|> namely nonpredictability by an automaton. But this cannot be tested with
|> finite samples of finite precision.
Nor can the hypothesis that a sample comes from a particular
distribution. Or, rather, it can be - subject to very similar,
but slightly extended, limitations.
|> > There are 'universal' tests, and some have been known for 70+ years.
|> > Computer scientists discovered them a couple of decades back, and
|> > announced them as new with a flourish of trumpets. I could probably
|> > think of half a dozen mathematically distinct ones if I put my mind
|> > to it.
|>
|> Please give a definition of 'random' that is reasonably well accepted,
|> and then an universal test for it.
As I pointed out, one of the meanings of 'random' in common use
is where statisticians would use 'independent' or 'ergodic',
especially in the context of a sequence. Anyway, an ergodic
sequence is an example of what most people will call a random
sequence. It's a standard term, and you will find clearer
definitions on the Web than I can write off the top of my head.
One of the oldest universal tests is a simple chi-squared test
for equidistribution, provided that you increase all of the number
of dimensions, the number of sections in each dimension and the
expected number of points in each cell. I can't remember offhand
if this handles singular distributions, but there are other tests
that do. Herman Rubin invented one based on the distance between
sample characteristics functions, which I have buried somewhere
or could rederive if I put my mind to it.
Note that the application of tests like the chi-squared and
Kolmogorov-Smirnov to samples from unknown distributions, in order
to test for independence, was common from the 1930s onwards.
Regards,
Nick Maclaren.
cma...@yahoo.com
Does reality care about the quantum state? Or is it only the observer
who cares about it?
Chris
Eugene Stefanovich
<cma...@yahoo.com> wrote in message
news:1123042429....@z14g2000cwz.googlegroups.com...
I don't think we should abandon "objective" reality. The radioactive nucleus
decays "objectively" at a certain point in time and emits "objective" decay
products. No mystery here. The only mystery is that we cannot predict
when exactly the decay will occur. Quantum mechanics sets a limit of
what we can know. There are some questions that simply cannot be answered.
That's the message of QM.
To me, this is not a disaster - this is a blessing. Nature draws for us
boundaries of what can be known. This inspires in me a hope that some
day people will solve all puzzles of nature and find answers to all
fundamental questions (that make sense). Otherwise, people would never
stop asking "why?" after finding an answer to the previous "why".
Eugene.
I.Vecchi
..
> Does reality care about the quantum state? Or is it only the observer
> who cares about it?
The point is that there is no objective reality beyond the quantum
state. The assumption that there is one is not just unnecessary, it is
physically meaningless and therefore a source of error.
Physics is about measurement outcomes (aka perceptions).
Reality (whatever that means) is a handy construct, whose
deconstruction arguably started with Descartes' demon and was furthered
by Kant, Berkeley, Kierkegaard all the way to Von Neumann, Bohr ,
Rovelli's RQM ([1]) and beyond.
These days we face the challenge (both conceptual and experimental) of
observer-dependent space-time metrics ([2]) and of macroscopic
superpositions/superposed observers ([3]). The sooner we get rid of
objectivist superstition, the better.
IV
PS This issue has been recently discussed in the thread "Is State
Vector Reduction a 'Process'?".
[1] http://arxiv.org/abs/quant-ph/9609002
[2] [Don't fall into the] "trap of assuming that there is a single
metric
for space-time, as there is in classical theory. In quantum theory, on
the other hand, one has to do a path integral over all possible
metrics. There will be different saddle points in the metric for
different questions. In particular the saddle point metrics for the
questions that outside observers ask will be different from the the
saddle point metric of an infalling observer." at
http://www.hawking.org.uk/text/public/public.html
[3] http://physicsweb.org/articles/world/13/8/3
----------------------------------------------------------------
I know not what they mean by things considered in themselves. This is
nonsense, jargon.
G.Berkeley, Notebook A, 832
Nick Maclaren
In article <1122700902....@g49g2000cwa.googlegroups.com>,
"I.Vecchi" <vec...@weirdtech.com> writes:
|> cma...@yahoo.com ha scritto:
|> >
|> > The real question is: Is nature deterministic or not? You seem to
|> > adhere to the view that it is not deterministic. But let's confirm this
|> > with this question: Given a pair of perfectly identical nuclei having
|> > EXACTLY THE SAME STATE {to every imaginable and inimaginable detail),
|> > and with similar neighborhoods. Does it seem plausible to you that they
|> > will take different amounts of time to decay?
|>
|> If one agrees that "the quantum state is just an expectation catalog
|> .. its purpose is to make predictions about possible measurement
|> results a specific observer does not know yet" ([1]), then obviously
|> yes.
|>
|> However in order to accept the above one has to give up deeply
|> ingrained metaphysical assumptions (aka superstitions) about
|> "objective" reality.
Eh? Why? What's wrong with a probabilistic formulation of
objective reality?
The simplest formulation (not the only one) states that the
future hasn't happened yet, the past is fixed, and the objective
reality specifies what will happen in terms of the probabilities
of events as the "arrow of time" moves on. I.e. events occur in
the present according to the objective probabilities, and then
are fixed for all time.
Regards,
Nick Maclaren.
cma...@yahoo.com
> cma...@yahoo.com ha scritto:
> ..
>
> > Does reality care about the quantum state? Or is it only the observer
> > who cares about it?
>
> The point is that there is no objective reality beyond the quantum
> state. The assumption that there is one is not just unnecessary, it is
> physically meaningless and therefore a source of error.
I know that this is the currently accepted view by most physicists. But
it sounds like religion to me.
> Physics is about measurement outcomes (aka perceptions).
Being short sighted I've developed a mistrust about perceptions. I know
that there is a truth beyond my perceptions. I don't see why it would
be any different regarding our perception of the laws of physics.
> Reality (whatever that means) is a handy construct,
I think we can define reality as the set of events. So my question
boils down to: "Does the set of events care about the quantum state?"
> whose deconstruction arguably started with Descartes' demon and was furthered
> by Kant, Berkeley, Kierkegaard all the way to Von Neumann, Bohr ,
> Rovelli's RQM ([1]) and beyond.
Since we are citing great names, why not mention the subject of this
discussion, namely Einstein? As you know, he was opposed to Bohr's
views. What do you think was wrong with him? Was he superstitious, or
maybe just turning senile?
> These days we face the challenge (both conceptual and experimental) of
> observer-dependent space-time metrics ([2]) and of macroscopic
> superpositions/superposed observers ([3]). The sooner we get rid of
> objectivist superstition, the better.
Again this sounds like religion to me, like some kind of inquisition.
There is simply no evidence that there is no truth beyond the quantum
state. So the "objectivists" are there to stay.
Chris
I.Vecchi
..
> ... What's wrong with a probabilistic formulation of
> objective reality?
>
> The simplest formulation (not the only one) states that the
> future hasn't happened yet, the past is fixed, and the objective
> reality specifies what will happen in terms of the probabilities
> of events as the "arrow of time" moves on. I.e. events occur in
> the present according to the objective probabilities, and then
> are fixed for all time.
I think we already had a related discussion. Basically, there is no
such thing as an objective probability. For the instance of Nick
McLaren who saw the cat dead the probability of observing it alive
again is zero, whereas as long as I don't talk to you about the
experiment's outcome (which I did not witness) Micio will subsist in a
hopeful superposition. Unitarity, ya know?
Cheers,
IV
PS Relevant(?) variations on this aria and references in my nearby
posts.
I.Vecchi
..
> The radioactive nucleus
> decays "objectively" at a certain point in time and emits "objective" decay
> products.
Well, no.
What you get is a superposition of instances of , say, Eugene
Stefanovich observing decay at different times.
As Zeh famously writes ([1]) "If the Schroedinger equation is instead
assumed to be universal and exact, superpositions of states of the
brain representing different contents of consciousness are as
unavoidable as Schroedinger superposition of a dead and alive cat".
IV
[1] "The Problem of Conscious Observation in Quantum Mechanical
Description" at http://www.arxiv.org/abs/quant-ph/9908084
I.Vecchi
..
>
> I think we can define reality as the set of events.
You mean the set of measurement outcomes/perceptions?
That's obviously observer-dependent.
..
>
> Since we are citing great names, why not mention the subject of this
> discussion, namely Einstein? As you know, he was opposed to Bohr's
> views. What do you think was wrong with him?
> Was he superstitious, or
> maybe just turning senile?
I do not agree with him , that's all.
IV
cma...@yahoo.com
> cma...@yahoo.com ha scritto:
> ..
> >
> > I think we can define reality as the set of events.
>
> You mean the set of measurement outcomes/perceptions?
> That's obviously observer-dependent.
There's nothing obvious about that.
>
> ..
> >
> > Since we are citing great names, why not mention the subject of this
> > discussion, namely Einstein? As you know, he was opposed to Bohr's
> > views. What do you think was wrong with him?
> > Was he superstitious, or
> > maybe just turning senile?
>
> I do not agree with him , that's all.
Yes, it's very convenient.
Chris
Nick Maclaren
In article <1123137516.1...@g14g2000cwa.googlegroups.com>,
Probably :-(
|> Basically, there is no
|> such thing as an objective probability.
Eh? Is that based on a form of mathematics I haven't heard of,
some interesting physics experiments (ditto), a philosophical
disbelief in probability or a religious tenet?
|> For the instance of Nick
|> McLaren who saw the cat dead the probability of observing it alive
|> again is zero, whereas as long as I don't talk to you about the
|> experiment's outcome (which I did not witness) Micio will subsist in a
|> hopeful superposition. Unitarity, ya know?
Well, that's a theory, I suppose. Do you have any evidence that
it is any more 'real' than other theories based on probability?
Regards,
Nick Maclaren.
Ralph Hartley
> I don't think we should abandon "objective" reality. The radioactive nucleus
> decays "objectively" at a certain point in time and emits "objective" decay
> products. No mystery here. The only mystery is that we cannot predict
> when exactly the decay will occur.
Afterward, there will also be an uncertainty in when exactly the decay
*did* occur.
It will be inversely proportional to the uncertainty in energy.
The Mossbauer effect decreases the uncertainty in energy of the photon,
and thus increases the minimum uncertainty in the time of emission.
So in a *sense* the Mossbauer effect does increase the "time required to
emit a photon", to the extent that the phrase makes sense at all.
If you don't like time as a variable, note that knowing the time of
emission is the same as knowing the photon's position at a given time,
and knowing its energy is the same as knowing its momentum (because
photons are massless).
> To me, this is not a disaster - this is a blessing. Nature draws for us
> boundaries of what can be known. This inspires in me a hope that some
> day people will solve all puzzles of nature and find answers to all
> fundamental questions (that make sense).
What a dreadful thought!
I'm not too worried.
Ralph Hartley
Eugene Stefanovich
Ralph Hartley wrote:
> Eugene Stefanovich wrote:
>
>> I don't think we should abandon "objective" reality. The radioactive
>> nucleus
>> decays "objectively" at a certain point in time and emits "objective"
>> decay
>> products. No mystery here. The only mystery is that we cannot predict
>> when exactly the decay will occur.
>
>
> Afterward, there will also be an uncertainty in when exactly the decay
> *did* occur.
What uncertainty? The event (decay) happened. The Geiger counter
clicked. The time of the click was registered by the experimenter and
entered in the journal. There is no uncertainty after the fact.
Eugene.
Cl.Massé
1123088197.1...@g49g2000cwa.googlegroups.com...
> [2] [Don't fall into the] "trap of assuming that there is a single
> metric
> for space-time, as there is in classical theory. In quantum theory, on
> the other hand, one has to do a path integral over all possible
> metrics.
> (at http://www.hawking.org.uk/text/public/public.html)
Why? Is there a wave propagating in the space of metric?
I.Vecchi
> In article <1123137516.1...@g14g2000cwa.googlegroups.com>,
> "I.Vecchi" <vec...@weirdtech.com> writes:
..
> |> Basically, there is no
> |> such thing as an objective probability.
>
> Eh? Is that based on a form of mathematics I haven't heard of,
> some interesting physics experiments (ditto), a philosophical
> disbelief in probability or a religious tenet?
If you are asking for references I already provided some relevant ones
in this thread. There are epistemic formulations of quantum probability
(see e.g. [1], based on De Finetti's subjectivist interpretation of
classical probability) that fit nicely into Rovelli's Relational QM
([2]). Actually if your read [3] carefully the jist is there. Besides,
the epistemic/subjective notion of probability is as old as the
concept itself. Remember Pascal's bet?
> |> For the instance of Nick
> |> McLaren who saw the cat dead the probability of observing it alive
> |> again is zero, whereas as long as I don't talk to you about the
> |> experiment's outcome (which I did not witness) Micio will subsist in a
> |> hopeful superposition. Unitarity, ya know?
>
> Well, that's a theory, I suppose. Do you have any evidence that
> it is any more 'real' than other theories based on probability?
If evolution is linear and unitary that's what you get, but in order to
put real beef on this, one has to detect superposed instances of Nick
McLaren who respectively heard or did not hear the Geiger counter
click.
Somewhat macroscopic superpositions are already being detected ([4]),
but admittedly we are still some way off from detecting superposed
observers. It is quite a challenge, but a concrete one.
IV
[1] http://arxiv.org/abs/quant-ph/0205039
[2] http://arxiv.org/abs/quant-ph/9609002
[3] "the quantum state is just an expectation catalog. Its purpose is
to make predictions about possible measurement results a specific
observer does not know yet" in Thomas Jennewein, Gregor Weihs, Jian-Wei
Pan, Anton Zeilinger" Reply to Ryff's comment ..." quant-ph/0303104
[4] http://physicsweb.org/articles/world/13/8/3
---------------------------------------------
"Maybe someone said this before. Anyways, I am saying it now."
Italo Vecchi aka me
r...@maths.tcd.ie
>Nick Maclaren ha scritto:
>> In article <1123137516.1...@g14g2000cwa.googlegroups.com>,
>> "I.Vecchi" <vec...@weirdtech.com> writes:
>> |> Basically, there is no
>> |> such thing as an objective probability.
>>
>> Eh? Is that based on a form of mathematics I haven't heard of,
>> some interesting physics experiments (ditto), a philosophical
>> disbelief in probability or a religious tenet?
The probabilities of individual measurement results associated
with a pure state in quantum mechanics are as close as
you can get to objective probabilities, in the sense that
two distinct observers, if they are to describe the
state of a system using a pure state, must use the
same pure state, and hence assign the same probabilities.
This is in contrast to the situation with mixed states,
where different people will in general assign different
probabilities depending on what information they have
available to them. EPR with spin-half particles gives
a good example of this, where Alice, having measured
the spin of her particle, assigns a pure state to
Bob's particle, even before Bob has made any measurement.
Since Bob doesn't know what result Alice got, he will
describe his particle with a density matrix.
Anyway, the debate here seems to be about the two
opposing views of probability theory. One of these
says that probability theory is used by humans in
the course of their calculations when they don't
have enough information to determine which
answer to a given question is the right one. They
must then assign probabilities to the various
answers on the basis of the information that they
do have. This view of probability has come to be
called Bayesian.
The other view is that there's something called randomness,
according to which a certain fact becomes true or a certain
event happens for absolutely no reason. Probability theory
must be used when dealing with such random processes, and
the aim of probability theory is to calculate how often
particular results will be obtained if an experiment is
repeated a large number of times using the same generator
of randomness. This is a much stonger view, since it makes
a metaphysical and ontological assertion about "ultimate
reality", declaring explicitly that a particular event
happens for no reason at all (as opposed to a merely
unknown reason). This view is taught in schools.
>> |> For the instance of Nick
>> |> McLaren who saw the cat dead the probability of observing it alive
>> |> again is zero, whereas as long as I don't talk to you about the
>> |> experiment's outcome (which I did not witness) Micio will subsist in a
>> |> hopeful superposition. Unitarity, ya know?
>>
>> Well, that's a theory, I suppose. Do you have any evidence that
>> it is any more 'real' than other theories based on probability?
>If evolution is linear and unitary that's what you get, but in order to
>put real beef on this, one has to detect superposed instances of Nick
>McLaren who respectively heard or did not hear the Geiger counter
>click.
>Somewhat macroscopic superpositions are already being detected ([4]),
>but admittedly we are still some way off from detecting superposed
>observers. It is quite a challenge, but a concrete one.
I don't see what you hope will be demonstrated by a
superposed-observer experiment. Suppose Nick is allowed to
see the cat and then a complicated interferometry experiment
is performed to detect interference between the Nick-alive cat
branch of the superposition and the Nick-dead cat branch.
Either the interference will be observed or quantum mechanics
is falsified. Assuming that quantum mechanics isn't going to
fail, the only interesting question we could put to Nick
would be "Did you see a living cat or a dead cat?"
We know his answer in advance. He'll say "I know it
was one or the other, but I don't remember which."
In order to detect the interference, his memory of
which branch he was in has to be wiped.
We might imagine that, since both possibilites (Nick
seeing a live cat and Nick seeing a deat cat) needed
to be taken into account in the calculations, those
two Nicks really existed and really had those experiences,
but this is merely our imagination at work. What we
would have at hand would be an individual who
remembers neither.
R.
scerir
> The point is that there is no objective reality
> beyond the quantum state.
Well, *sometimes* there is - at least it seems so, to me -
some (objective) reality beyond the quantum state.
I mean, there is a quantum-Zeno effect, there are 'weak'
measurements, retrodictions are *sometimes* possible,
even in the orthodox interpretation, by means of
the eigenstate-eigenvalue rule. I would say that
the quantum state reflects not what is actually known,
about the system, but what is knowable, about the system.
But, yes, within that system we (observers and apparata) are.
So, it is well possible that we are measuring ourselves.
(I'm not sure the relational QM, by Rovelli, Mermin,
and Aage Bohr [1], provides the ultimate answer to all
that [2]) .
Regards,
serafino
[1] "Perhaps surprisingly, the very notion of genuine
fortuitousness is powerful in its implications.
With particles excluded, only geometry is left on the
stage, and the symmetry of spacetime itself, through
its representations, provides the mathematical formalism
of quantum mechanics. Once that point is recognized,
quantum mechanics emerges from the principle of genuine
fortuitousness combined with the embodiment of spacetime
symmetry, without any reference to degrees of freedom
of particles or fields. The theory, exclusively concerned
with probability distributions of genuinely fortuitous
clicks, thus differs from previous physical theories in
that it does not deal with objects to be measured - which
eliminates the issue of a quantum world."
-Aage Bohr
http://www.physicstoday.org/vol-57/iss-10/p15.html
[2] "This statistical interpretation is now universally accepted
as the best possible interpretation for quantum mechanics, even
though many people are unhappy with it. People had got used
to the determinism of the last century, where the present
determines the future completely, and they now have to get used
to a different situation in which the present only gives one
information of a statistical nature about the future. A good many
people find this unpleasant; Einstein has always objected to it.
The way he expressed it was: 'The good God does not play with dice'.
Schroedinger also did not like the statistical interpretation and
tried for many years to find an interpretation involving determinism
for his waves. But it was not successful as a general method.
I must say that I also do not like indeterminism. I have to accept it
because it is certainly the best that we can do with our present
knowledge. One can always hope that there will be future developments
which will lead to a drastically different theory from the present
quantum mechanics and for which there may be a partial return
of determinism. However, so long as one keeps to the present formalism,
one has to have this indeterminism".
-P.A.M. Dirac, "The Development Of Quantum Mechanics" - "Conferenza
Tenuta il 14 Aprile 1972, in Roma, Accademia Nazionale dei Lincei",
1974, 11 pages.
Nick Maclaren
In article <1123222882.3...@o13g2000cwo.googlegroups.com>,
"I.Vecchi" <vec...@weirdtech.com> writes:
|>
|> > |> Basically, there is no
|> > |> such thing as an objective probability.
|> >
|> > Eh? Is that based on a form of mathematics I haven't heard of,
|> > some interesting physics experiments (ditto), a philosophical
|> > disbelief in probability or a religious tenet?
|>
|> If you are asking for references I already provided some relevant ones
|> in this thread. There are epistemic formulations of quantum probability
|> (see e.g. [1], based on De Finetti's subjectivist interpretation of
|> classical probability) that fit nicely into Rovelli's Relational QM
|> ([2]). Actually if your read [3] carefully the jist is there. Besides,
|> the epistemic/subjective notion of probability is as old as the
|> concept itself. Remember Pascal's bet?
No, you haven't. You have missed my point, and it is the same one
that is made at the end of your reference [3].
I know perfectly well that there are other formulations - I know
of at least four, and could probably think of more - but you claimed
that the objective probability one was known to be false (i.e. that
there is no such thing - see above). I am stating that you have not
justified your claim.
The objective probability model is a perfectly good explanation and
I, for one, have no problem with thinking of the universe in such
terms. This is probably why I became a statistician :-)
This in no way says that the other explanations are inferior.
Regards,
Nick Maclaren.
I.Vecchi
..
> I don't see what you hope will be demonstrated by a
> superposed-observer experiment. Suppose Nick is allowed to
> see the cat and then a complicated interferometry experiment
> is performed to detect interference between the Nick-alive cat
> branch of the superposition and the Nick-dead cat branch.
>
> Either the interference will be observed or quantum mechanics
> is falsified. Assuming that quantum mechanics isn't going to
> fail,
I'll go with that
> the only interesting question we could put to Nick
> would be "Did you see a living cat or a dead cat?"
>
> We know his answer in advance. He'll say "I know it
> was one or the other, but I don't remember which."
> In order to detect the interference, his memory of
> which branch he was in has to be wiped.
>
> We might imagine that, since both possibilites (Nick
> seeing a live cat and Nick seeing a deat cat) needed
> to be taken into account in the calculations, those
> two Nicks really existed and really had those experiences,
> but this is merely our imagination at work. What we
> would have at hand would be an individual who
> remembers neither.
No. We disagree on this, i.e. we disagree on an issue that in principle
(and therefore sooner or later in practice too) can be experimentally
tested .
There is no reason why Nick should not remember. Being observed does
not brainwash people (*).
After the experiment Nick will tell us "the cat was dead" or "the cat
was alive" and anyways we will see the cat, dead or alive.
We will show Nick the experimental records and tell him "see, these are
the recorded interference pattern of your <cat dead> and <cat alive>
branches. Of course the patterns were detected and recorded before you
talked with us and/or we saw the cat dead [or alive]. Absorbing that
information [i.e. performing a measurement in that basis] collapsed us
too into one of the branches, the one corresponding to the state of the
cat that you observed and remember. Team B guys are currently
detecting our interference patterns with our other branches. They will
show them to us later, but as soon as they will check whether the cat
is dead/alive or hear from us about it , they will also collapse into
the branch which is entangled with the outcome that we observed. Team C
is detecing Team B's interference patterns ... "
Cheers,
IV
(*) Nick's memory erasure corresponds to reversing collapse
(re-coherence or whatever), which is irrelevant here. There is no
reason to expect any fundamental difference between Nick's and SQUID
currents' superpositions [1].
[1] http://physicsweb.org/articles/world/13/8/3
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"Experiments kick ass"
Galileo, private communication