fine-tuned Universe, anthropic principle, teleology, etc.
robert bristow-johnson
talk pages) regarding the FTU and AP?
what about the FTU is generally accepted science?
what dimensionless fundamental constants of nature (or dimensionful,
if you think so) are known to have to be constrained in some range in
order for matter to exist or to form as it has, for stars and
astronomical structures to form evolve as they have and to sustain as
long as they do, for a wide range of elements to emerge naturally on
little rocky planets like ours?
how does the use of the AP to explain Dicke coincidences and the age
of the Universe compare to using the AP to explain the ostensible fine-
tuning of universal constants?
i would like to separate what is physics and what is a more general
epistemology.
r b-j
robert bristow-johnson
is there a way i can frame the question better, enough so that people
in the know might respond?
e.g. what is known about the range of values of the fine-structure
constant that makes it compatible with atoms forming and existing as
they do? what would be the consequence if it was 2% larger or
smaller? what would happen if it was 10% larger or smaller?
or the gravitational coupling constant (usually defined as (m_e/m_P)^2
but other elementary particles could be used instead for reference)?
or the relative masses (to m_e) of the quarks or other leptons (from
which mu = 1836.15 might be derived)?
or the coupling constants in these weird matrices (CKM and PMNS) that
i admittedly do not understand.
or the cosmological constant.
what do we know about any subset of these numbers, that if they were
sufficiently different then matter would not exist as we understand
it? or that the internal reactions in stars might be that they do not
cook up the heavier elements or survive as long as they do (for life
to evolve on little rocky planets like ours).
i would like to know a little more detail regarding the premise
surrounding the so-called "fine-tuned Universe" concept. i read John
Baez saying "certainly some constants could be wiggled quite a bit
without any serious effect, ... does anyone really claim that changing
the tau lepton mass by 2%, or even 20%, would make a bloody shred of
difference to life as we know it? How would that happen, exactly? I've
never heard of the tau lepton having any effect on any physics that
really matters to us."
so my question is if the mass of the tau lepton is not presently known
to make any difference, what other fundamental constants share that
status? and what fundamental constants *are* known to necessarily be
in some range surrounding their currently measured value?
is the question too vague? how can i focus or rephrase it?
r b-j
On Jan 19, 1:45�pm, robert bristow-johnson <r...@audioimagination.com>
wrote:
X-Phy
wrote:
The AP is not in the domain of science, not even of epistemology.
Yet, from the point of view of epistemology, it is sensless, since the
universal constants don't exist but are only a human invention, even
though they can be measured. Our scientific knowledge is still
incomplete to make such strong statement.
Let's take an example. Pi could be considered a universal constant,
and is measurable. But that isn't true since it can be calculated
from a set of axioms. That said, does it make sense to say that a
slighly different value of pi wouldn't have allowed man to exist, and
to draw some principle from that? No, since there is no fine tuning
in those axioms.
Now, it is true that changing slightly the value of some universal
constant would give a universe where the man wouldn't have arisen (for
example, too much radioactivity in the bones.) That is a scientific
statement, but none of the statements drawn from it are.
--
X-Phy
robert bristow-johnson
>
> The AP is not in the domain of science, not even of epistemology.
it seems to me that the application of the AP to the Dicke
coincidences, and specifically why the Universe appears to be in the
ballpark of 10^10 years old, rather than 10^8 years nor 10^12 years,
*is* solidly in the purview of science. it seems to turn the question
around, from "Why is the Universe about 10^10 years old?" into "How
much time would be required for the Universe to develop to the point
that there is sufficient elemental diversity, small rocky planets, and
sufficiently young stars for beings to evolve that can ask the
question?"
> since the
> universal constants don't exist but are only a human invention, even
> though they can be measured.
the choice to toss in a factor of 4*pi into the definition is a human
decision, but how is it that humans *invented* the ratio of
alpha = e^2/(4*pi*eps_0*hbar*c)
that dimensionless ratio of physical quantity exists whether humans
have thunked about it or not. and its value has consequences, no?
> �ｿｽOur scientific knowledge is still
> incomplete to make such strong statement.
i'm trying to get a census among those who count themselves physicists/
cosmologists regarding *which* constants our present science *is*
complete enough to make such a statement.
> Let's take an example. Pi could be considered a universal constant,
> and is measurable.
it's a mathematical constant, and it is *not* measurable. we do not
measure pi. not a good example.
the numbers i am thinking about are the fine-structure constant (which
can be thought of as the square of the ratio of the electron charge to
the Planck charge), the gravitational coupling constant (which can be
thought of as the square of the ratio of the electron mass to the
Planck mass), the relative masses of other leptons and quarks to that
of the electron, the coupling constants in those weird matrices in the
Standard Model, the cosmological constant (expressed in terms of
Planck units).
> �ｿｽBut that isn't true since it can be calculated
> from a set of axioms. �ｿｽThat said, does it make sense to say that a
> slightly different value of pi wouldn't have allowed man to exist, and
> to draw some principle from that? �ｿｽNo, since there is no fine tuning
> in those axioms.
it's not about pi or e or Euler's gamma. it's about some 26-odd
dimensionless universal (at least we *think* they're universal)
numbers that have *no* root other than that of measurement in physical
experiment. some of them matter, some might not (but i am not sure
which ones do not).
> Now, it is true that changing slightly the value of some universal
> constant would give a universe where the man wouldn't have arisen (for
> example, too much radioactivity in the bones.) �ｿｽThat is a scientific
> statement, but none of the statements drawn from it are.
what drawn statements are you referring to?
r b-j
X-Phy
wrote:
> > Let's take an example. Pi could be considered a universal constant,
> > and is measurable.
> it's a mathematical constant, and it is *not* measurable. �we do not
> measure pi. �not a good example..
We can measure pi provided that the space is Euclidean, that is, in a
region where there is no gravitational field. So its value is a
constant in Newtonian theory, it isn't in general relativity. The
fine structure constant could also be the value of a mathematical
constant in a theory beyond electromagnetism, and in a theory still
beyond it could have a different value. For example there is the
speculative theory of cosmic strings (not superstrings) in which the
universal constants are different in different parts of the Universe.
That's why we must always be cautious about such strong affirmation.
> the numbers i am thinking about are the fine-structure constant (which
> can be thought of as the square of the ratio of the electron charge to
> the Planck charge), the gravitational coupling constant (which can be
> thought of as the square of the ratio of the electron mass to the
> Planck mass), the relative masses of other leptons and quarks to that
> of the electron,
They all are in the form of a ratio, just like pi.
> the coupling constants in those weird matrices in the
> Standard Model, the cosmological constant (expressed in terms of
> Planck units).
Those constants aren't universal, they are rather parameters.
> it's not about pi or e or Euler's gamma. �it's about some 26-odd
> dimensionless universal (at least we *think* they're universal)
> numbers that have *no* root other than that of measurement in physical
> experiment.
Before Euclidean geometry, pi had no root other than that of
measurement. The ratio of the circumference over the diameter is a
physical quantity since it is linked to the curvature of space-time.
> > Now, it is true that changing slightly the value of some universal
> > constant would give a universe where the man wouldn't have arisen (for
> > example, too much radioactivity in the bones.) �That is a scientific
> > statement, but none of the statements drawn from it are.
> what drawn statements are you referring to?
Such as the anthropic principle.
--
X-Phy
robert bristow-johnson
> On 4 f�v, 17:30, robert bristow-johnson <r...@audioimagination.com>
> wrote:
>
> > > Let's take an example. Pi could be considered a universal constant,
> > > and is measurable.
> > it's a mathematical constant, and it is *not* measurable. �we do not
> > measure pi. �not a good example..
>
> We can measure pi provided that the space is Euclidean,
we can only measure finite-precision approximations to pi. and we
know of computations of pi to hundreds of thousands of digits. but we
cannot measure pi. and pi is not a physical constant. but alpha is.
> that is, in a
> region where there is no gravitational field. �So its value is a
> constant in Newtonian theory, it isn't in general relativity. �The
> fine structure constant could also be the value of a mathematical
> constant in a theory beyond electromagnetism, and in a theory still
> beyond it could have a different value. �For example there is the
> speculative theory of cosmic strings (not superstrings) in which the
> universal constants are different in different parts of the Universe.
> That's why we must always be cautious about such strong affirmation.
>
> > the numbers i am thinking about are the fine-structure constant (which
> > can be thought of as the square of the ratio of the electron charge to
> > the Planck charge), the gravitational coupling constant (which can be
> > thought of as the square of the ratio of the electron mass to the
> > Planck mass), the relative masses of other leptons and quarks to that
> > of the electron,
>
> They all are in the form of a ratio, just like pi.
not just like pi. pi has meaning without the concept of electron
charge or mass or electrons themselves.
> > the coupling constants in those weird matrices in the
> > Standard Model, the cosmological constant (expressed in terms of
> > Planck units).
>
> Those constants aren't universal, they are rather parameters.
perhaps they are different at the Andromeda galaxy, but we think those
parameters are the same as they are here.
>
> > it's not about pi or e or Euler's gamma. �it's about some 26-odd
> > dimensionless universal (at least we *think* they're universal)
> > numbers that have *no* root other than that of measurement in physical
> > experiment.
>
> Before Euclidean geometry, pi had no root other than that of
> measurement.
that's an "accident" of (human) history. pi, as a mathematical
"concept" (i am not saying who is around to conceptualize it) existed
before there were people, whose descendants discovered Euclidian
geometry.
> �The ratio of the circumference over the diameter is a
> physical quantity since it is linked to the curvature of space-time.
the measurement (with finite accuracy) of real physical items *do*
have something to do with pi. but the exact number and the concept
exist in the mathematical domain which exists before any physical
statements of axioms are laid down.
> > > Now, it is true that changing slightly the value of some universal
> > > constant would give a universe where the man wouldn't have arisen (for
> > > example, too much radioactivity in the bones.) �That is a scientific
> > > statement, but none of the statements drawn from it are.
> > what drawn statements are you referring to?
>
> Such as the anthropic principle.
i think the WAP need not be drawn from anywhere. it's essentially a
tautology. a truth, but a vacuous truth.
r b-j
X-Phy
wrote:
> > Before Euclidean geometry, pi had no root other than that of
> > measurement.
> that's an "accident" of (human) history.
How can you say the fine structure constant isn't an "accident" of
history? A theory isn't reality, it only describes, or rather is
intended to describe, reality. The fine structure constant isn't
real.
--
X-Phy
Bob_for_short
>
> How can you say the fine structure constant isn't an "accident" of
> history? �A theory isn't reality, it only describes, or rather is
> intended to describe, reality. �The fine structure constant isn't
> real.
>
First of all, alpha is dimensionless but it is not just a ratio of two
different charges or masses in our theory. So our theory is not
perfect and it does not explain this value.
Next, they say alpha is a coupling constant as if the charge and the
quantized electromagnetic field could be safely decoupled. Those who
believe so encounter divergences in their calculations. It's a serious
problem.
Third, alpha never occurs separately in QED calculations. For example,
the expansion parameter is in fact alpha*ln(w/m), where w is the
photon frequency. The dimensionless factor ln(w/m) varies. It is the
reason of the infra-red divergence. So the expansion parameter is not
1/137 but something more complicated. Thinking solely of alpha is
misleading way to learn nature because it is not the only parameter
involved.
We know too little about nature, in my opinion. I admit there is a
belief that we know nearly everything and a Theory of Everything is
coming up. But the truth is quite different. People like self-
flattering, self-fooling, and showing off.
As to AP, there so many unhappy people on the Earth, there is so much
injustice that speaking of fine-tuned constants is incorrect. With the
same "theoretical constants" many people cannot afford elementary
things. For them these constants are certainly badly tuned.
robert bristow-johnson
again, whether there is a factor of 4pi tossed in or not is a human
decision.
but the number that we assemble (using any consistent system of units)
as
e^2/(eps_0*hbar*c)
is a real and positive dimensionless number that has something to do
with physical reality. and it matters whether it's around 1/10 or
around 1/1000 or around 10. unlike pi or 2 or whatever mathematical
constant, the source of that alpha number is only from physical
measurement, there isn't yet an accepted theory that presents a
derivation of its value from pure theory. perhaps, someday, some
anthropic argument can put lower and upper limits to alpha and as the
theory gets refined, the lower and upper limits can converge to
virtually each other, and then they have a theory for why alpha is
what it is.
i surprized we're having an argument about fundamental (dimensionless)
physical constants vs. mathematical constants. they're not the same
species of animal.
r b-j
FrediFizzx
news:e573cbec-8591-491c...@o28g2000yqh.googlegroups.com...
> On 6 f�v, 13:06, X-Phy <xphysic...@gmail.com> wrote:
>>
>> How can you say the fine structure constant isn't an "accident" of
>> history? A theory isn't reality, it only describes, or rather is
>> intended to describe, reality. The fine structure constant isn't
>> real.
>>
> I agree with X-Phy.
>
> First of all, alpha is dimensionless but it is not just a ratio of two
> different charges or masses in our theory. So our theory is not
> perfect and it does not explain this value.
My personal suspicion is that alpha is geometrical in nature.
> Next, they say alpha is a coupling constant as if the charge and the
> quantized electromagnetic field could be safely decoupled. Those who
> believe so encounter divergences in their calculations. It's a serious
> problem.
Take a radio transmitter and turn it on. Then turn it off; isn't the
radiation (quantized EM field) that is already propagating "decoupled"
from the source? So the divergences are only for SOME calculations.
Which ones?
> Third, alpha never occurs separately in QED calculations. For example,
> the expansion parameter is in fact alpha*ln(w/m), where w is the
> photon frequency. The dimensionless factor ln(w/m) varies. It is the
> reason of the infra-red divergence. So the expansion parameter is not
> 1/137 but something more complicated. Thinking solely of alpha is
> misleading way to learn nature because it is not the only parameter
> involved.
Probably true.
Best,
Fred Diether
robert bristow-johnson
> "Bob_for_short" <vladimir.kalitvian...@wanadoo.fr> wrote in message
>
> news:e573cbec-8591-491c...@o28g2000yqh.googlegroups.com...
>
> > On 6 f v, 13:06, X-Phy <xphysic...@gmail.com> wrote:
>
> >> How can you say the fine structure constant isn't an "accident" of
> >> history? A theory isn't reality, it only describes, or rather is
> >> intended to describe, reality. The fine structure constant isn't
> >> real.
>
> > I agree with X-Phy.
>
> > First of all, alpha is dimensionless but it is not just a ratio of two
> > different charges or masses in our theory.
well, the number we get from e^2/(eps_0*c*hbar) *can* be considered a
simple ratio of like quantity ( say e^2/(eps_0*h) to c or e to
sqrt(eps_0*c*hbar)
> > So our theory is not
> > perfect and it does not explain this value.
>
> My personal suspicion is that alpha is geometrical in nature.
>
yeah or maybe is the square of the elementary charge measured in
natural units like Planck units. maybe, in mother nature's world, all
these dimensionful constants of free space go away, the electron
charge is -0.30282212.. just an pet speculation.
> > Next, they say alpha is a coupling constant as if the charge and the
> > quantized electromagnetic field could be safely decoupled. Those who
> > believe so encounter divergences in their calculations. It's a serious
> > problem.
>
> Take a radio transmitter and turn it on. Then turn it off; isn't the
> radiation (quantized EM field) that is already propagating "decoupled"
> from the source? So the divergences are only for SOME calculations.
> Which ones?
>
> > Third, alpha never occurs separately in QED calculations. For example,
> > the expansion parameter is in fact alpha*ln(w/m), where w is the
> > photon frequency. The dimensionless factor ln(w/m) varies.
but the fine-structure constant they publish a value of at NIST is
that alpha that scales ln(w/m), right? since the natural log is the
log without being scaled, there is no reason why anything should scale
that alpha, right?
> > It is the
> > reason of the infra-red divergence. So the expansion parameter is not
> > 1/137 but something more complicated. Thinking solely of alpha is
> > misleading way to learn nature because it is not the only parameter
> > involved.
>
> Probably true.
probably something went over my head here. but i don't understand
whether alpha is the only parameter involved is an issue. as long
that it *is* a parameter involved, it seems to me to be perfectly
reasonable to say that life would be different if it were to change
sufficiently. it would begin with just measuring the difference. but
i'm would think that at some point physicists better than me (like,
they understand the standard model) would know that something would
change in atomic structures and the nature of matter would change.
with alpha far enough off, isn't it plausible that there would be some
elements or isotopes that would be different enough that chemical
processes and biological processes would not be the same?
r b-j
Bob_for_short
>
> Take a radio transmitter and turn it on. �Then turn it off; isn't the
> radiation (quantized EM field) that is already propagating "decoupled"
> from the source? �So the divergences are only for SOME calculations.
> Which ones?
>
But there is no alpha involved in the classical wave radiation theory!
Should we extrapolate classical notions to the microscopic scale? No
because it does not work. Take, for example, a black body radiation.
It needs another hypothesis about the electromagnetic wave energy and
needs h_bar. Take, for example, an atom. It needs a "wave mechanics"
with h_bar and strangely smeared charges in atoms to explain the atom
stability. There is still no alpha in the Schroedinger equation. That
is why alpha appears there only as a "fine structure" constant - a
tiny and minor effect. You see, we go from classical (simplifies)
notions towards more and more precise description of nature and every
time we encounter conceptual and mathematical problems. Even in the
Classical Electrodynamics we have an infinite electromagnetic mass and
self-accelerating solutions so our CE is not perfect, admit it.
When the Classical Mechanics was developed, Laplace advanced a
deterministic vision of our world: it suffices to know the initial
data for everything and the rest can be calculated and predicted.
Since then we met relativism, uncertainty, and incompleteness (G�del).
That's a lesson to our aspirations.
As was said, alpha is a constant that we arrived at in our, human
attempts to describe micro physics at a certain stage. Apparently it
is not the only thing involved in reality. QED encounters divergences
when alpha is considered as a "small" parameter in initially decoupled
charge and its electromagnetic filed. On the other hand, in the same
QED it is proven that there is no decoupling even in the asymptotic
states. Our way of the theory construction is imperfect. We have to
recognize that the charge and its electromagnetic filed are coupled
permanently and cannot be separated. (I personally made an attempt to
construct an Novel QED where the electron and the quantized EMF are
features of one compound system. It helps to preserve the energy-
momentum conservation laws without self-action and infinities.)
So asking why alpha is equal to 1/137 is even not similar to asking
why Me/Mp = 1/1836. It is similar to asking "why did I meet my future
wife in the middle of June"? Such is our history of progressive
learning physical phenomena and we are still far from grasping the
essentials, in my opinion. We tend (if not bound) to simplify
everything to get it in our human, limited scope of imagining.
John Park
> On Feb 6, 9:46 pm, "FrediFizzx" <fredifi...@hotmail.com> wrote:
>> "Bob_for_short" <vladimir.kalitvian...@wanadoo.fr> wrote in message
>>
>> news:e573cbec-8591-491c...@o28g2000yqh.googlegroups.com...
>>
>> > On 6 f v, 13:06, X-Phy <xphysic...@gmail.com> wrote:
>>
>> >> How can you say the fine structure constant isn't an "accident" of
>> >> history? A theory isn't reality, it only describes, or rather is
>> >> intended to describe, reality. The fine structure constant isn't
>> >> real.
>>
>> > I agree with X-Phy.
>>
>> > First of all, alpha is dimensionless but it is not just a ratio of two
>> > different charges or masses in our theory.
>
> well, the number we get from e^2/(eps_0*c*hbar) *can* be considered a
> simple ratio of like quantity ( say e^2/(eps_0*h) to c or e to
> sqrt(eps_0*c*hbar)
[...]
As I recall, alpha is the ratio of the "speed" of an electron in the first
Bohr orbit of the hydrogen atom to the speed of light. Granted, neither the
first Bohr orbit nor the speed of an electron in it are exactly physical, but
that interpretation does also suggest that other factors of 2 or pi or
whatever are unwarranted.
--John Park
Bob_for_short
>
> As I recall, alpha is the ratio of the "speed" of an electron in the first
> Bohr orbit of the hydrogen atom to the speed of light. Granted, neither the
> first Bohr orbit nor the speed of an electron in it are exactly physical, but
> that interpretation does also suggest that other factors of 2 or pi or
> whatever are unwarranted.
>
Yes, that's right: alpha = v_0/c, but v_0 is not itself
"fundamental" but calculated from e and h_bar.
(I wonder if v_0 is the same for Hydrogen, meso-atom, and
positronium?)
John Park
> On Feb 7, 8:08�pm, af...@FreeNet.Carleton.CA (John Park) wrote:
>
>>
>> As I recall, alpha is the ratio of the "speed" of an electron in the first
>> Bohr orbit of the hydrogen atom to the speed of light. Granted, neither the
>> first Bohr orbit nor the speed of an electron in it are exactly physical, but
>> that interpretation does also suggest that other factors of 2 or pi or
>> whatever are unwarranted.
>>
>
> Yes, that's right: alpha = v_0/c, but v_0 is not itself
> "fundamental" but calculated from e and h_bar.
Sort of what I was saying.
>
> (I wonder if v_0 is the same for Hydrogen, meso-atom, and
> positronium?)
>
Not sure what you mean by meso-atom, but probably not, and almost certainly
not for positronium. The calculation is strictly for the reduced mass, which
is approximately the electron mass to the extent that m_e << m_nucleus.
(Factor of two difference in v if the masses are equal, I seem to recall.)
--John Park
robert bristow-johnson
it does not change the order of magnitude that this fundamental
constant is about. personally, i really like "rationalized" Planck
Units (G is replaced with 4*pi*G and 4*pi*eps_0 is replaced with
eps_0) sorta like Heaviside-Lorentz units with hbar and 4*pi*G
normalized. Charles Francis has mentioned some QFT theory where the
elementary charge is the same: sqrt(4*pi*alpha) = 0.302822 .
from this POV, alpha is derived from the more fundamental number which
is the amount of charge, measured in these most natural units, that
Nature has assigned to the electron, etc. if the charge was
different, the speed of the electron in the sorta classical Bohr
model, would be different (relative to c).
but we choose which parameter comes first. and whether tossing in a
4*pi makes it "simpler" or more natural or not.
r b-j
island
> On Jan 19, 1:45 pm, robert bristow-johnson <r...@audioimagination.com>
> wrote:
>
>
>
> > can we parse a little the discussion we see (say, on the Wikipedia
> > talk pages) regarding the FTU and AP?
>
> > what about the FTU is generally accepted science?
>
> > what dimensionless fundamental constants of nature (or dimensionful,
> > if you think so) are known to have to be constrained in some range in
> > order for matter to exist or to form as it has, for stars and
> > astronomical structures to form evolve as they have and to sustain as
> > long as they do, for a wide range of elements to emerge naturally on
> > little rocky planets like ours?
>
> > how does the use of the AP to explain Dicke coincidences and the age
> > of the Universe compare to using the AP to explain the ostensible fine-
> > tuning of universal constants?
>
> > i would like to separate what is physics and what is a more general
> > epistemology.
>
> > r b-j
You might find this lecture helpful:
http://abyss.uoregon.edu/~js/21st_century_science/lectures/lec28.html
But I think that you will find that Dicke's "golden age" is the
commonality that is found in all of the illustrated precariously
balanced constants and conditions that are necessary to life:
http://abyss.uoregon.edu/~js/images/instability.gif
This includes the observed near-"flat", balanced structure of the
universe, as well as our own local ecobalances, that exist similarly
fixed between diametrically opposing runaway tendencies that send
conditions racing to extremes that are equally prohibitive to carbon
based life:
http://www.astronomynotes.com/solarsys/s9.htm
And I think that you will also find that this commonality extends to
include all similarly evolved galaxies and planets that exist within
the galactic and intergalactic "habitable zones":
http://www.daviddarling.info/images/galactic_habitable_zone.jpg
So the principle isn't strictly anthropic, although the conditions for
life are extremely restricted by the synchronized fine-tuning that
derives this commonality.
island
> On Jan 19, 1:45 pm, robert bristow-johnson <r...@audioimagination.com>
> wrote:
>
>
>
> > can we parse a little the discussion we see (say, on the Wikipedia
> > talk pages) regarding the FTU and AP?
>
> > what about the FTU is generally accepted science?
>
> > what dimensionless fundamental constants of nature (or dimensionful,
> > if you think so) are known to have to be constrained in some range in
> > order for matter to exist or to form as it has, for stars and
> > astronomical structures to form evolve as they have and to sustain as
> > long as they do, for a wide range of elements to emerge naturally on
> > little rocky planets like ours?
>
> > how does the use of the AP to explain Dicke coincidences and the age
> > of the Universe compare to using the AP to explain the ostensible fine-
> > tuning of universal constants?
>
> > i would like to separate what is physics and what is a more general
> > epistemology.
>
> > r b-j
You might find this lecture helpful: