Discussion Topic: Double slit experiments, one quantum at a time
Jay R. Yablon
With this post, I would like to initiate a group discussion of the
double slit experiment, when it is performed one quantum at a time. The
goal is to see if we can make any headway toward a "better," for
"physical" explanation of this experiment, than any which has been
developed at present. Like everyone else, I am on a journey over this
perplexing experiment. The link below is a good point of reference for
this discussion:
http://en.wikipedia.org/wiki/Double-slit_experiment#When_observed_emission_by_emission
I shall especially refer to the figure linked below, which shows
electron buildup over time in a double slit experiment.
http://en.wikipedia.org/wiki/Image:Double-slit_experiment_results_Tanamura_2.jpg
Now, let us suspend everything we know or have been taught about double
slit, and see if we can dispassionately, scientifically describe what
going on is in the progression of figures from a) to e), foregoing
interpretation for the moment. Since we need some language, I will use
the term "point" to describe each "pinprick" on these figures. This is
what I would say about these figures:
1) The end-pattern of aggregate buildup labeled e) is identical to the
interference pattern which is arrived at from the old "wave models" of
light which existed back in the days of Young, way before we knew about
quantum mechanics
2) Although collectively identical, in the aggregate, to the wave
pattern from the old wave model of light, each "point" which contributes
to this pattern arrived on the detector individually, one point at a
time.
3) If we had never known of Young's experiments, and if the first
double slit experiments ever performed had been performed one electron
or photon at a time, we would have described light as a series of
particles which probabilistically build up into the pattern at e) which
resembles the interference pattern when we pass waves of water through
two slits. (I emphasize *water*, not *light*, because wave models of
light were built out of wave observations of water, and because wave
models of light originated from the aggregate observed patterns of
million of quanta, before we knew about quanta.) That Young's
experiment with large aggregates of quanta was done before experiments
one quantum at a time was an *historical accident* which conditioned
humans to think about light in a misleading way. For the discussion
from here, let's make believe that we performed one-quantum-at-a-time
experiments before we ever performed aggregate, Young-type experiments,
and let's see what language we might then use describe things, were we
to block (unlearn) all that we know from Young's experiments.
4) Further, let us discard the "magical" notion that any single
electron ever went through "both slits at the same time" and somehow
"collapsed" to a point only once we observed it, and see if we can use
some other, more directly-physical language to describe what is
happening here.
5) Let us for sake of discussion suppose that there are roughly 10,000
points on figure e), and that roughly 5,000 quanta went through each
slit. They then formed the pattern on e).
6) Let us for sake of discussion suppose we change the experiment so as
to cover slit a), shoot 5,000 quanta through slit b), then cover slit b)
and shoot 5,000 more through slit a). We know that we would observe a
very different pattern.
7) I would then say the following, dispassionately and scientifically,
in a effort to describe what has happened, referring to the slits as
slit a) and slit b):
8) When an electron passes through slit a) and slip b) is *open*, the
probability distribution for where the electron will end up on the
detector is *different* than the probability distribution where the
electron will end up if slit b) is *closed*. And vice versa.
9) The fact that another slit nearby the slit that quantum passes
through is *open* versus *closed*, or has an *active* versus *inactive*
detector, therefore affects the probability function which governs where
the particle will eventually land on the detector.
10) In this view, we are prompted to ask a very physical question: when
a quantum passes through slit a), what is it about slit b) being open or
closed (or active versus inactive detectors) which affects the
probability function for where that quantum will eventually strike the
detector?
11) The question in 10) is still a difficult question, but at least it
is a question about physics, rather than a vague assertion that the
particle has a dual nature, or is in two places at once, or collapses.
There is NOTHING about figures a) through e) in the link above which
justifies referring to a single quantum of light as a "wave." The most
we can say is that the probability distribution for a single quantum to
strike the detector, when both slits are open, precisely resembles a
wave interference pattern. We then ask: why and how is it that the
openness of both slits affect the probability distribution in this way?
12) I would like at this point to submit that we think very hard about
the vacuum which the field quanta are traveling though, and at this
point, I refer to a post I made a couple of nights ago to set up the
foundation for this discussion. That post is at:
http://home.nycap.rr.com/jry/Papers/Hidden%20Variables.pdf
13) In particular, let us suppose that by leaving the second slit open
rather than closed, we have effectively reconfigured the quantum vacuum
which the quanta are traveling through when they pass through a slit.
An open slit, even when no electron travels through it, still creates a
different vacuum environment than exists when there is a closed slit.
And let us suppose that it is this difference in the vacuum, which
causes a difference in the probability pattern. Just as in the above
link, it is the way in which fluctuations in the vacuum are configured,
which determines where the particles land on the detector, in the end.
Thus, we need to figure out in precise terms how the vacuum becomes
reconfigured to yield the probabilities we observe for quanta to strike
the detector, and, we need to identify a real, physical mechanism to
cause this vacuum reconfiguration which effectively alters the *forces*
acting on field quanta traveling through the vacuum.
14) In sum, to go beyond hocus pocus, however, we need to go further to
suggest what the *physics mechanism might be* for an open slit to case a
different environment than a closed slit, for the travel of quanta. If
will make the suggestion, for now as a *qualitative* suggestion, the we
give serious consideration to some form of *Casimir effect* as being
responsible for this shift the in probability function based on a nearby
slit that the electron does not pass through.
15) For example, consider the link at:
http://physicsweb.org/articles/world/15/9/6
This says: "What happens if you take two mirrors and arrange them so
that they are facing each other in empty space? Your first reaction
might be "nothing at all". In fact, both mirrors are mutually attracted
to each other by the simple presence of the vacuum." Think of an open
slit, which we shall call "no mirror." Now, close the slit by putting
in a "mirror." We know from Casimir, that the effect of adding a
mirror, i.e., plugging a slit, will cause a shift in the forces in the
nearby vacuum. This force will not only effect other nearby "mirrors,"
but other nearby "quanta" traveling through the vacuum. In this way,
this will affect the probability for where the quantum will strike the
detector. Alternatively, think of an open slit as a "cavity" in the
sense of Casimir. If the a quantum passes through one slit, but there
is a second open slit nearby which is a "Casimir Cavity," then the
effects from inside this cavity may well leak out to affect quanta
traveling through a nearby cavity / slit. If it can be shown that the
Casimir force with and without a "mirror" plugging a slit causes a shift
in the pattern between the known one-slit and two-slit aggregate
interference patterns, then it may be possible to arrive at an
explanation of double slit results which does not at all rely on
wave-particle duality, but has a completely physical foundation in
Casimir effects in the vacuum.
This does not forego, by any means, the utility of associating a
"wavelength" with an electron and with a photon, but it would avoid the
oddities of a particle being "at two places at the same time," or of a
wavefunction suddenly "collapsing" as soon as we make an observation,
and possibly other oddities as well.
Respectfully submitted as food for thought and discussion.
Jay
_____________________________
Jay R. Yablon
Email: jya...@nycap.rr.com
Web site: http://home.nycap.rr.com/jry/FermionMass.htm
Co-moderator, sci,physics.foundations
Oh No
>10) In this view, we are prompted to ask a very physical question:
>when a quantum passes through slit a), what is it about slit b) being
>open or closed (or active versus inactive detectors) which affects the
>probability function for where that quantum will eventually strike the
>detector?
>
>11) The question in 10) is still a difficult question, but at least it
>is a question about physics, rather than a vague assertion that the
>particle has a dual nature, or is in two places at once, or collapses.
>There is NOTHING about figures a) through e) in the link above which
>justifies referring to a single quantum of light as a "wave." The most
>we can say is that the probability distribution for a single quantum to
>strike the detector, when both slits are open, precisely resembles a
>wave interference pattern. We then ask: why and how is it that the
>openness of both slits affect the probability distribution in this way?
>
>12) I would like at this point to submit that we think very hard
>about the vacuum which the field quanta are traveling though, and at
>this point, I refer to a post I made a couple of nights ago to set up
>the foundation for this discussion. That post is at:
I agree with what you say up to this point, but I think the terminology
"field quanta" brings in precisely the sort of unscientific notion that
you are rightly trying to dispel.
>13) In particular, let us suppose that by leaving the second slit open
>rather than closed, we have effectively reconfigured the quantum vacuum
>which the quanta are traveling through when they pass through a slit.
>An open slit, even when no electron travels through it, still creates a
>different vacuum environment than exists when there is a closed slit.
>And let us suppose that it is this difference in the vacuum, which
>causes a difference in the probability pattern.
The same with the terminology "reconfigure the quantum vacuum".
Certainly something has been reconfigured, but I would put it
differently. There is, and has been since Descartes, an ongoing
discussion in philosophy about the structure of space. We do not have
any empirical or scientific demonstration that the fundamental structure
of space is well modelled by the mathematical notion of a continuum. If
one examines carefully and logically the language of analysis one will
find that in mathematics the structure of a continuum is rigorously
constructed as an approximation to empirical truth, and not the other
way about.
This is called the substantivalist/relationalist debate. The relationist
position, following Descartes and Leibniz is that the structure of space
only arises from relationships between physical bodies. The
substantivalist position is that the manifold has some form of real
physical existence. Physisicists tend to assume substantivalism, while
philosophers lean toward relationalism.
In the context of the relationalist position there is a clear, obvious
and natural answer to your question. When the second slit is closed the
thing which has been reconfigured is the structure of matter. Physical
relationships in matter have been changed, ergo the structure of space
has been changed. This then ought to be the cause of the change to the
interference pattern.
The thing which has been absent from this position is mathematical
proof. When I was seventeen and first came into contact with these
phenomena and the discussions in relativity and quantum theory it
appeared to me that, with the development of many valued logics,
mathematics had advanced far enough that a proof was technically
feasible, based on the fundamental notion of relativity of position,
just as Einstein had proved various things using the notion of
relativity of motion.
That then became the object of my research. Everything I studied prior
to attempting such a proof, from pure mathematics to logic to qed to
general relativity has been directed at finding that proof. That is what
I believe I have furnished in Relational Quantum Gravity.
The fact of predictions in new physics and cosmology arising from this
research has been an unexpected bonus. Young's slits and astronomical
measurement appear a long way removed from each other. Yet I think most
physicists recognise that a single theory of physics should incorporate
both. Many people will not follow the subtleties in the arguments, but
any astronomer can run the tests I have described on local stars. The
results of those tests make the substantivalist position of most
relativists quite untenable.
Regards
--
Charles Francis
moderator sci.physics.foundations.
substitute charles for NotI to email
harry
"Jay R. Yablon" <jya...@nycap.rr.com> wrote in message
news:55k0gpF...@mid.individual.net...
> Dear SPF friends:
>
> With this post, I would like to initiate a group discussion of the double
> slit experiment, when it is performed one quantum at a time. The goal is
> to see if we can make any headway toward a "better," for "physical"
> explanation of this experiment, than any which has been developed at
> present. Like everyone else, I am on a journey over this perplexing
> experiment.
Great! This is one of the main topics that I like to see discussed. I have
some comments on your analysis below.
> The link below is a good point of reference for this discussion:
>
> http://en.wikipedia.org/wiki/Double-slit_experiment#When_observed_emission_by_emission
>
> I shall especially refer to the figure linked below, which shows electron
> buildup over time in a double slit experiment.
>
> http://en.wikipedia.org/wiki/Image:Double-slit_experiment_results_Tanamura_2.jpg
>
> Now, let us suspend everything we know or have been taught about double
> slit, and see if we can dispassionately, scientifically describe what
> going on is in the progression of figures from a) to e), foregoing
> interpretation for the moment.
OK
> Since we need some language, I will use the term "point" to describe each
> "pinprick" on these figures. This is what I would say about these
> figures:
>
> 1) The end-pattern of aggregate buildup labeled e) is identical to the
> interference pattern which is arrived at from the old "wave models" of
> light which existed back in the days of Young, way before we knew about
> quantum mechanics
OK
> 2) Although collectively identical, in the aggregate, to the wave pattern
> from the old wave model of light, each "point" which contributes to this
> pattern arrived on the detector individually, one point at a time.
I think that that is inaccurate:
"arriving" suggests either a travelling pinprick (which is impossible) or
else something related to the pinprick and that has a localized trajectory
towards the pinprick (but we certainly don't know that, and QM theory
appears to suggests that that is wrong).
I propose:
Each "point" that contributes to this pattern appeared on the detector
individually, one point at a time.
> 3) If we had never known of Young's experiments, and if the first double
> slit experiments ever performed had been performed one electron or photon
> at a time, we would have described light as a series of particles which
> probabilistically build up into the pattern at e) which resembles the
> interference pattern when we pass waves of water through two slits. (I
> emphasize *water*, not *light*, because wave models of light were built
> out of wave observations of water, and because wave models of light
> originated from the aggregate observed patterns of million of quanta,
> before we knew about quanta.) That Young's experiment with large
> aggregates of quanta was done before experiments one quantum at a time was
> an *historical accident* which conditioned humans to think about light in
> a misleading way. For the discussion from here, let's make believe that
> we performed one-quantum-at-a-time experiments before we ever performed
> aggregate, Young-type experiments, and let's see what language we might
> then use describe things, were we to block (unlearn) all that we know from
> Young's experiments.
Almost OK. That that historical accident "conditioned humans to think about
light in a misleading way" is a personal opinion that is "due to what has
been taught"; thus it should be "suspended". It's a possible outcome of this
discusssion to determine if and to what extend wave models are "misleading",
or if instead one should develop some kind of wave model based on the
results of one-quantum-at-a-time experiments.
> 4) Further, let us discard the "magical" notion that any single electron
> ever went through "both slits at the same time" and somehow "collapsed" to
> a point only once we observed it, and see if we can use some other, more
> directly-physical language to describe what is happening here.
OK on the whole: probably most people agree that it doesn't make sense to
think that a physical "collapse" takes place in the way of the mathematical
"collapse". But note that I see nothing "magical" in the notion that every
single electron went through both slits.
> 5) Let us for sake of discussion suppose that there are roughly 10,000
> points on figure e), and that roughly 5,000 quanta went through each slit.
> They then formed the pattern on e).
Not OK: there is no reason to believe that "quanta" go through individual
slits. Thus, maybe put it like this:
"Let us for sake of discussion suppose that there are roughly 10,000
points on figure e), and that roughly 10,000 quanta went through the
slits. They then formed the pattern on e)."
> 6) Let us for sake of discussion suppose we change the experiment so as
> to cover slit a), shoot 5,000 quanta through slit b), then cover slit b)
> and shoot 5,000 more through slit a). We know that we would observe a
> very different pattern.
OK
> 7) I would then say the following, dispassionately and scientifically, in
> a effort to describe what has happened, referring to the slits as slit a)
> and slit b):
OK of course. :-)
> 8) When an electron passes through slit a) and slip b) is *open*, the
> probability distribution for where the electron will end up on the
> detector is *different* than the probability distribution where the
> electron will end up if slit b) is *closed*. And vice versa.
Here you base yourself on one possible model. IF that model is true, THEN
OK.
> 9) The fact that another slit nearby the slit that quantum passes through
> is *open* versus *closed*, or has an *active* versus *inactive* detector,
> therefore affects the probability function which governs where the
> particle will eventually land on the detector.
Following the same model of a stone-like particle in flight, OK.
One should not a priory exclude some kind of wave mechanism.
See also http://tinyurl.com/2l5vys and http://tinyurl.com/2mkbo9
> 10) In this view, we are prompted to ask a very physical question: when a
> quantum passes through slit a), what is it about slit b) being open or
> closed (or active versus inactive detectors) which affects the probability
> function for where that quantum will eventually strike the detector?
I suppose that you mean: If indeed an electron passes through slit a). Then
yes, OK.
> 11) The question in 10) is still a difficult question, but at least it is
> a question about physics, rather than a vague assertion that the particle
> has a dual nature, or is in two places at once, or collapses.
It's instead an alternative model to the one in which the electron does not
travel as a particle.
> There is NOTHING about figures a) through e) in the link above which
> justifies referring to a single quantum of light as a "wave."
I disagree: e) clearly shows some waviness. Thus it's an obvious model to
consider.
> The most we can say is that the probability distribution for a single
> quantum to strike the detector, when both slits are open, precisely
> resembles a wave interference pattern. We then ask: why and how is it
> that the openness of both slits affect the probability distribution in
> this way?
OK - that is an excellent description of the topic of this thread.
> 12) I would like at this point to submit that we think very hard about
> the vacuum which the field quanta are traveling though, and at this point,
> I refer to a post I made a couple of nights ago to set up the foundation
> for this discussion. That post is at:
>
> http://home.nycap.rr.com/jry/Papers/Hidden%20Variables.pdf
"Traveling field quanta", what are that? Anyway, that post is surely
interesting, and for sure we are dealing with some kind of black box that we
try to "crack". IMO the probaility distrubution is caused by the strip with
one or two slits (often oversimplified as "by the slits"). From your
write-up I got a different impression, but below you present it in a way
that seems to be similar.
> 13) In particular, let us suppose that by leaving the second slit open
> rather than closed, we have effectively reconfigured the quantum vacuum
> which the quanta are traveling through when they pass through a slit. An
> open slit, even when no electron travels through it, still creates a
> different vacuum environment than exists when there is a closed slit. And
> let us suppose that it is this difference in the vacuum, which causes a
> difference in the probability pattern.
Again staying with your model, that looks OK to me.
> Just as in the above link, it is the way in which fluctuations in the
> vacuum are configured, which determines where the particles land on the
> detector, in the end. Thus, we need to figure out in precise terms how the
> vacuum becomes reconfigured to yield the probabilities we observe for
> quanta to strike the detector, and, we need to identify a real, physical
> mechanism to cause this vacuum reconfiguration which effectively alters
> the *forces* acting on field quanta traveling through the vacuum.
I personally doubt very much that fluctuations cause the diffraction pattern
(wich is in essence what you mean, if I understand correctly).
> 14) In sum, to go beyond hocus pocus, however, we need to go further to
> suggest what the *physics mechanism might be* for an open slit to case a
> different environment than a closed slit, for the travel of quanta. If
> will make the suggestion, for now as a *qualitative* suggestion, the we
> give serious consideration to some form of *Casimir effect* as being
> responsible for this shift the in probability function based on a nearby
> slit that the electron does not pass through.
Interesting idea!
> 15) For example, consider the link at:
>
> http://physicsweb.org/articles/world/15/9/6
>
> This says: "What happens if you take two mirrors and arrange them so that
> they are facing each other in empty space? Your first reaction might be
> "nothing at all". In fact, both mirrors are mutually attracted to each
> other by the simple presence of the vacuum." Think of an open slit, which
> we shall call "no mirror." Now, close the slit by putting in a "mirror."
> We know from Casimir, that the effect of adding a mirror, i.e., plugging a
> slit, will cause a shift in the forces in the nearby vacuum.
A shift in net radiation pressure, yes. But could that work for pressure on
photons?
> This force will not only effect other nearby "mirrors," but other nearby
> "quanta" traveling through the vacuum. In this way, this will affect the
> probability for where the quantum will strike the detector.
> Alternatively, think of an open slit as a "cavity" in the sense of
> Casimir. If the a quantum passes through one slit, but there is a second
> open slit nearby which is a "Casimir Cavity," then the effects from inside
> this cavity may well leak out to affect quanta traveling through a nearby
> cavity / slit. If it can be shown that the Casimir force with and without
> a "mirror" plugging a slit causes a shift in the pattern between the known
> one-slit and two-slit aggregate interference patterns, then it may be
> possible to arrive at an explanation of double slit results which does not
> at all rely on wave-particle duality, but has a completely physical
> foundation in Casimir effects in the vacuum.
My intuition tells me that probably this is a wrong lead - but I must admit
that I never thought of it!
> This does not forego, by any means, the utility of associating a
> "wavelength" with an electron and with a photon, but it would avoid the
> oddities of a particle being "at two places at the same time," or of a
> wavefunction suddenly "collapsing" as soon as we make an observation, and
> possibly other oddities as well.
>
> Respectfully submitted as food for thought and discussion.
>
> Jay
Thanks,
Harald
Jay R. Yablon
To add further grist to the discussion, let's talk for a few minutes
about diffraction. Diffraction does not gain the same attention as
double slit experiments or path integrals (infinite slit, infinite
screen gedankens), but are also important to understand the properties
of light and matter. To wit:
1) If I were to shine light past the "edge / corner" of an object,
toward a detector, and to do so "one quantum at a time," am I correct to
presume that "one pinprick at a time" would show up on the detector, and
that the larger-scale pattern we associate with diffraction, including
the "wavy" "bending" of light around the corner, would only emerge after
we have emitted a very large number of quanta?
2) Am I correct to assume ditto for a single aperture? (aperture =
slit or pinhole) That is, that the "wavy" pattern of diffraction
through a single aperture also builds up quantum impact by quantum
impact?
3) If this is so as I believe it is, many of the questions I employed
to start this thread regarding double slit experiments, apply here as
well. The quanta (electrons or photons) do appear on the detector very
much as particles, and those properties we associate with a wave only
become apparent after a large, aggregate buildup of particles. In this
way, "wave" describes not the single "corpuscles" of emission and
absorption, but rather, the probability pattern which describes how
large numbers of corpuscles will distribute themselves in the aggregate.
In other words, "wave" appears to be a description of the probability
pattern of the aggregate phenomenon, not of the individual quantum
contributors to the pattern.
4) Here too, as with the double slit experiments, we need to ask how
the "corner" or the "aperture" causes the probability distribution for
each quanta to be that which we associate with the diffraction of light
around a corner or through an aperture.
5) Further, if we try to understand this based on the vacuum which
these quanta are traveling through, then we must ask, again, how the
vacuum proximate a corner or aperture becomes configured to yield the
probabilities we observe for quanta to strike the detector, and so too,
we need to identify a real, physical mechanism to cause this vacuum
reconfiguration which effectively alters the *forces* acting on field
quanta traveling through the vacuum.
6) My main point in all of this, is that although the double slit
experiment is given much attention, this question of why individual
quanta, in the aggregate, distribute into "wavy" probability patterns is
not a "double aperture" question. This question arises as soon as one
considers even a single aperture, and even as soon as one considers a
mere "corner" such that of any object with defined boundaries. If we
want to therefore understand these phenomena one step at a time, on
physical terms, by a progression from simpler questions to more
difficult ones, it is prudent methodology to start with corner- and
single-aperture-diffraction before tackling double slits and path
integrals.
7) The double slit experiments introduce the further complication that
if one opens only slit a) and fires a large number of quanta through and
then opens only slit b) and then fires some more quanta through, the
probability distribution for where a given quantum will reach the
detector is different than the probability distribution for opening both
slits at the same time and then firing quanta through.
8) I have a question: all of the "slit" experiments I read about are
done with "openings." Do experiments show any difference if a "slit" is
a transparent, but hard physical medium like glass, versus a physical
opening? (my guess is not, other than added refractory effects, but I
am trying to gather accurate data to help me formulate these questions.)
9) I will try in the near future to give a more detailed presentation
of how, as I introduced at the start of this thread, Casimir / vacuum
effects might turn out to be at the root of all of this.
10) One other experimental point very worth noting (I think Harry
raised this). Photons and electrons both do the same thing in
diffraction experiments. Electrons carry a charge and photons do not.
Therefore, the electric charge appears to be irrelevant to diffraction
phenomena. Once the electric charge is factored out, all that the
photon and the electron have in common is their energy content.
Gravitation is the interaction which "sees" all energy and does not
distinguish anything else. In the Planck vacuum, gravitation is the
predominant interaction. This further points toward Planck vacuum
effects as a possible physical mainspring of diffraction phenomena,
since we are effectively observing an "equivalence principle" as between
how electrons and photons diffract.
Thanks to Charles and Harry for their very helpful comments and input.
Jay.
_____________________________
Jay R. Yablon
Email: jya...@nycap.rr.com
Web site: http://home.nycap.rr.com/jry/FermionMass.htm
Co-moderator, sci.physics.foundations
Oh No
>
>To add further grist to the discussion, let's talk for a few minutes
>about diffraction. Diffraction does not gain the same attention as
>double slit experiments or path integrals (infinite slit, infinite
>screen gedankens), but are also important to understand the properties
>of light and matter. To wit:
>
>1) If I were to shine light past the "edge / corner" of an object,
>toward a detector, and to do so "one quantum at a time," am I correct to
>presume that "one pinprick at a time" would show up on the detector, and
>that the larger-scale pattern we associate with diffraction, including
>the "wavy" "bending" of light around the corner, would only emerge after
>we have emitted a very large number of quanta?
I believe many of the "double slit" experiments performed in practice
are actually defraction experiments. Iirc this was so for the experiment
on buckminster fullerene I referenced in an earlier response to Fred.
>
>2) Am I correct to assume ditto for a single aperture? (aperture =
>slit or pinhole) That is, that the "wavy" pattern of diffraction
>through a single aperture also builds up quantum impact by quantum
>impact?
Yes.
>
>3) If this is so as I believe it is, many of the questions I employed
>to start this thread regarding double slit experiments, apply here as
>well. The quanta (electrons or photons) do appear on the detector very
>much as particles, and those properties we associate with a wave only
>become apparent after a large, aggregate buildup of particles. In this
>way, "wave" describes not the single "corpuscles" of emission and
>absorption, but rather, the probability pattern which describes how
>large numbers of corpuscles will distribute themselves in the aggregate.
Yes.
>In other words, "wave" appears to be a description of the probability
>pattern of the aggregate phenomenon, not of the individual quantum
>contributors to the pattern.
That is right. We never actually detect a wave. We detect a probability
pattern which happens to have the same form as a wave interference
pattern. Using strict deductive reasoning it is impossible to say that
the interference pattern is caused by a wave. All we can say is that
whatever mathematical apparatus correctly describes the probabilistic
behaviour of individual particles must yield the same pattern. Of course
there are instances to numerous to mention where quite different
phenomena lead to the same mathematical formula, so the appearance of
the same pattern as we get in wave interference does not justify the
conclusion that there is a wave in any physical sense.
>4) Here too, as with the double slit experiments, we need to ask how
>the "corner" or the "aperture" causes the probability distribution for
>each quanta to be that which we associate with the diffraction of light
>around a corner or through an aperture.
>
>5) Further, if we try to understand this based on the vacuum which
>these quanta are traveling through, then we must ask, again, how the
>vacuum proximate a corner or aperture becomes configured to yield the
>probabilities we observe for quanta to strike the detector, and so too,
>we need to identify a real, physical mechanism to cause this vacuum
>reconfiguration which effectively alters the *forces* acting on field
>quanta traveling through the vacuum.
Indeed. But see my earlier remarks about the vacuum. This is not a
concept we can justify or even describe empirically.
>
>6) My main point in all of this, is that although the double slit
>experiment is given much attention, this question of why individual
>quanta, in the aggregate, distribute into "wavy" probability patterns is
>not a "double aperture" question.
Right. We only use the double slit experiment because of the ease and
familiarity of its description.
> This question arises as soon as one
>considers even a single aperture, and even as soon as one considers a
>mere "corner" such that of any object with defined boundaries. If we
>want to therefore understand these phenomena one step at a time, on
>physical terms, by a progression from simpler questions to more
>difficult ones, it is prudent methodology to start with corner- and
>single-aperture-diffraction before tackling double slits and path
>integrals.
I think the analysis of the double slit is actually the simplest.
>7) The double slit experiments introduce the further complication that
>if one opens only slit a) and fires a large number of quanta through and
>then opens only slit b) and then fires some more quanta through, the
>probability distribution for where a given quantum will reach the
>detector is different than the probability distribution for opening both
>slits at the same time and then firing quanta through.
Nonetheless, that is an important part of the illustration of quantum
behaviour and rather easier to describe for a double slit than other
experiments.
>
>8) I have a question: all of the "slit" experiments I read about are
>done with "openings." Do experiments show any difference if a "slit" is
>a transparent, but hard physical medium like glass, versus a physical
>opening? (my guess is not, other than added refractory effects, but I
>am trying to gather accurate data to help me formulate these questions.)
I believe refraction through crystal lattices is also used
experimentally in place of a diffraction grating.
>9) I will try in the near future to give a more detailed presentation
>of how, as I introduced at the start of this thread, Casimir / vacuum
>effects might turn out to be at the root of all of this.
I don't think that idea works at all well. Note that quantum mechanical
effects are unchanged with different particles used in the experiments.
>
>10) One other experimental point very worth noting (I think Harry
>raised this). Photons and electrons both do the same thing in
>diffraction experiments. Electrons carry a charge and photons do not.
>Therefore, the electric charge appears to be irrelevant to diffraction
>phenomena. Once the electric charge is factored out, all that the
>photon and the electron have in common is their energy content.
>Gravitation is the interaction which "sees" all energy and does not
>distinguish anything else. In the Planck vacuum, gravitation is the
>predominant interaction. This further points toward Planck vacuum
>effects as a possible physical mainspring of diffraction phenomena,
>since we are effectively observing an "equivalence principle" as between
>how electrons and photons diffract.
Note that gravity, as described in general relativity, is not an
interaction but the consequence of the geometry of space-time. It was
found in consequence of Einstein's recognition in special relativity
that geometrical relationships are properties of measurement of matter
relative to matter, not of matter relative to a background ether. What I
have done in relational quantum gravity is simply take that principle to
its logical conclusion. Not only is motion relative, but position is
relative too. In relativity you cannot say how something is moving
unless you say how it is moving relative to other matter. In quantum
theory you cannot say where something is unless you say where it is
relative to other matter. In order to have a position relative to other
matter, the particle must interact with other matter. If it does not
interact as it passes through the slits, it has no position relative to
the slits.
In relational quantum gravity I have analysed rigorously and
mathematically the consequences to geometry when all measurement is
relative. The result of extending the principle of relativity so that it
applies to position as well as motion is the geometrical unification of
general relativity with quantum theory. The actual mathematical
construction of relational quantum gravity is not that difficult. What
is difficult is maintaining the mental discipline to avoid polluting the
description of the empirical realisation of geometrical relationships
with preconceived notions about the structure of space-time. Only when
one learns to think of physics in terms in which space-time has no
fundamental role can quantum theory be understood.
Thomas
>The quanta (electrons or photons) do appear on the detector very
> much as particles, and those properties we associate with a wave only
> become apparent after a large, aggregate buildup of particles.
What the detector actually registers are not the electrons or
'photons', but the results of their interaction with atoms in the
detector. Even for a homogeneous electromagnetic wave field, this
interaction will, due to the statistical properties of the material,
only produce a reaction at certain random times and places. The latter
will then merely be modulated by the interference pattern of the wave
field, and this modulation will obviously become more prominent in the
case of sufficiently high intensities of the electromagnetic wave or
sufficiently high integration times.
So if one considers an electromagnetic wave train resulting from the
emission of an individual atom, then this could, for an ideal
detector, produce an interference pattern on its own, but in reality
its intensity is simply so low that it will at best produce a reaction
in a couple of points in the detector, i.e. one needs many such wave
trains for the interference pattern to become clearly visible.
For electrons (and other particles), the question arises whether the
interference pattern is actually due to them, or maybe due to light
(i.e. electromagnetic waves) emitted simultaneously together with them
(either when the particles are produced in the first place or when
they hit the edges of the slits).
Thomas
Oh No
>On 13 Mar, 03:25, "Jay R. Yablon" <jyab...@nycap.rr.com> wrote
>>The quanta (electrons or photons) do appear on the detector very
>> much as particles, and those properties we associate with a wave only
>> become apparent after a large, aggregate buildup of particles.
>
>What the detector actually registers are not the electrons or
>'photons', but the results of their interaction with atoms in the
>detector. Even for a homogeneous electromagnetic wave field, this
>interaction will, due to the statistical properties of the material,
>only produce a reaction at certain random times and places. The latter
>will then merely be modulated by the interference pattern of the wave
>field, and this modulation will obviously become more prominent in the
>case of sufficiently high intensities of the electromagnetic wave or
>sufficiently high integration times.
>So if one considers an electromagnetic wave train resulting from the
>emission of an individual atom, then this could, for an ideal
>detector, produce an interference pattern on its own,
This is wrong. Single particles are always detected singly.
Thomas
> Thus spake Thomas <thomas.s...@gmail.com>
I was talking about the detection events produced by the interaction
of electromagnetic waves with the atoms in the detector material, not
that produced by particle reactions (both can lead to apparently
discrete reactions in the material).
Thomas
Cl.Massé
The topology of the double slit experiment is the same as the one of the EPR
type experiment. A single particle or two correlated ones are sent at space
type separated location, and it (they) meet(s) again. Each time, there is a
closed loop. Despite what would say intuition, there is no faster than
light information travel. That is true for the EPR type experiment, but
that is also true for the double slit experiment, even though the
information travel isn't obvious. So, in the case the particle is detected
at a slit, there is enough time to send the information to the other beam
roughly to the effect: "I'll be a little late, we have to cancel our
interference party. Manage it alone."
In most of the problem posed by QM, that "feedback" is forgotten. The
simpler example is as follow: A particle in a spherical state is send from
point. Two detectors are set up at the same distance from that point, but
in opposite direction. As soon as one detector fire, we know the other one
can't, although no information has been sent to it. But in order to
investigate that experimentally, we have to gather the data of the detectors
at one point. We get again the same topology, and the paradox can be solved
in the same way.
Today's physics is modelled only with the notion of (infinitesimal) segment,
or (locally) (pseudo-)Euclidean space. Already the Michelson-Morley
experiment was a loop topology that yielded a contradiction with theory. A
solution has been found at the expense of the notion of simultaneity (same
time.) Physics should be ultimately modelled only with the notion of loop,
perhaps at the expense of the notion of locality (same location.) In that
respect, it is interesting to note that in a space-time diagram, the EPR
type experiment is the space equivalent to the procedure of clock
synchronization.
--
~~~~ clmasse on free F-country
Liberty, Equality, Profitability.
Oh No
>In most of the problem posed by QM, that "feedback" is forgotten. The
>simpler example is as follow: A particle in a spherical state is send
>from point. Two detectors are set up at the same distance from that
>point, but in opposite direction. As soon as one detector fire, we
>know the other one can't, although no information has been sent to it.
>But in order to investigate that experimentally, we have to gather the
>data of the detectors at one point. We get again the same topology,
>and the paradox can be solved in the same way.
>
>Today's physics is modelled only with the notion of (infinitesimal)
>segment, or (locally) (pseudo-)Euclidean space. Already the Michelson-
>theory. A solution has been found at the expense of the notion of
>simultaneity (same time.) Physics should be ultimately modelled only
>with the notion of loop, perhaps at the expense of the notion of
>locality (same location.) In that respect, it is interesting to note
>that in a space-time diagram, the EPR type experiment is the space
>equivalent to the procedure of clock synchronization.
Broadly speaking I think this is right. Measurement is a self
referential process. We measure matter in the universe with respect to
matter in the universe, this sets up a loop in the logic or in the
mathematics and interference effects are the result. Unfortunately I
haven't come across a clear and simple way of putting this which makes
the result obvious. The procedure of clock synchronization is logically
necessary before it is possible to talk of a remote time coordinate.
Similar procedures are necessary before it is possible to talk of a
remote distance coordinate.
Spin is intrinsically necessary to the structure of space-time, it is
required in the description of relativistic particles and it is
fundamental in the interaction of electrons and photons. The properties
of this interaction are an intrinsic part of measurement processes which
give structure to space time. The apparent faster than light effect in
EPR is not really a faster than light effect because until the
information is taken, slower than light from A to B space-time does not
have its complete structure. In the absence of such structure it is not
fully possible to talk of the distance between the particles in the
entangled pair.
I don't thick we have to sacrifice locality. Each fundamental particle
is sizeless, because size makes no sense without measurement. It can
only interact by being in contact with another particle, e.g. an
electron is "in contact" with a photon at the time of emission. In a
black hole we have lots of particles in contact, and occupying the same
location.
PD
> Dear SPF friends:
>
> With this post, I would like to initiate a group discussion of the
> double slit experiment, when it is performed one quantum at a time. The
> goal is to see if we can make any headway toward a "better," for
> "physical" explanation of this experiment, than any which has been
> developed at present. Like everyone else, I am on a journey over this
> perplexing experiment. The link below is a good point of reference for
> this discussion:
>
>
> I shall especially refer to the figure linked below, which shows
> electron buildup over time in a double slit experiment.
>
What you propose with the configuration of the quantum vacuum, is
essentially a hidden variable theory.
It is interesting to compare this with the EPR gedanken, the theorem
by Jon Bell that says that it is possible to detect whether *any*
hidden variable is at work, and the subsequent experiments by Aspect
et al. which definitely ruled out the presence of a hidden variable of
any kind in an EPR kind of experiment.
So now you have a double problem: how to explain why the hidden
variables in a quantum vacuum operating would manifest themselves in a
Young-like experiment and NOT in an Aspect-like experiment.
PD
Jay R. Yablon
news:1173891438....@y80g2000hsf.googlegroups.com...
>>
>> _____________________________
>
> What you propose with the configuration of the quantum vacuum, is
> essentially a hidden variable theory.
> It is interesting to compare this with the EPR gedanken, the theorem
> by Jon Bell that says that it is possible to detect whether *any*
> hidden variable is at work, and the subsequent experiments by Aspect
> et al. which definitely ruled out the presence of a hidden variable of
> any kind in an EPR kind of experiment.
> So now you have a double problem: how to explain why the hidden
> variables in a quantum vacuum operating would manifest themselves in a
> Young-like experiment and NOT in an Aspect-like experiment.
>
> PD
>
PD:
That is exactly correct. If this experiment yields the predictions I
made, then we do have, in spades, "a double problem: how to explain why
the hidden variables in a quantum vacuum operating would manifest
themselves in a Young-like experiment and NOT in an Aspect-like
experiment." If the opposite result is observed, then we do not have
the double problem you mention, but we are confronted with what would
appear to be a superluminal communication of information to the
electron.
What makes this experiment different from Aspect, I believe, is that we
are not dealing directly with entanglement in the sense of, e.g.,
preparing two electrons at the same time, sending them off in opposite
directions, and seeing if action of some sort upon one correlates with
behavior then manifested by the other even thought they have a spacelike
separation. This experiment transmits single electrons through a
Young-type double-aperture grating such as has been around for over 200
years, repeats this over and over until one can see what sort of buildup
distribution appears on the detector, but makes last minute changes to
the grating which -- assuming the luminosity or subluminosity of all
signals, but no superluminosity -- would not have a chance to "catch up"
to the electron or photon as that passes through the grating. Thus, an
electron could go through a double-aperture grating but not show
interference, or could go through a single-aperture grating and show
interference, unless there is a superluminal information transfer about
the last minute change in grating.
I would be curious if someone can articulate whether there is some way
in which my experiment is in fact testing for an entanglement -- which
is not readily apparent to me because it tests the very simple case of
one quantum at a time, period. So far as I can tell, this experiment is
really a very direct test for superluminosity and hidden variables, not
entanglement. Entanglement is only addressed indirectly, in the sense
that entanglement may be defined as communication between two (or more)
spacelike-separated quanta which in classical conception, requires
superluminosity.
Put another way, this experiment will either create a serious crisis for
quantum mechanics by showing the operation of hidden variables in the
quantum vacuum, or, it will leave quantum mechanics alone, but
demonstrate a superluminal transfer of information. I would love to
know which of these results nature will show us, (or, perhaps, something
totally surprising), but in my estimation, this experiment brings the
tension between quantum theory and special relativity directly to an
"experimental head" using the most elemental apparatus of a diffraction
grating with last-minute reconfigurability such that last minute changes
cannot reach the electron without superluminosity. The verdict this
experiment is designed to render is:
a) superliminosity but no hidden vacuum variables, or
b) hidden vacuum variables but no superluminosity, or
c) something else which nature has in store that we don't yet know about
. . .???
We need to keep an open mind, especially for c), which could bring us to
the cusp of something wholly new. My gut tells me that we may need to
find a way to decouple "entanglement" from "superluminosity," and find a
way to understand the likely-affirmative phenomenon of entanglement
consistently with the likely-negative phenomenon of superluminosity.
I will try in the next day or so to make some comments pertaining to the
practicality of devising the apparatus to conduct this experiment.
(Remember, my business is patents. I spend all of my professional time
describing how to build working inventions and, by the way, have already
filed a patent application on this experimental apparatus, so that this
proposed apparatus configuration can be independently evaluated for
novelty.) With a few days of hindsight since developing the schematic
concept of the experiment, I think a photon experiment is easier to
manage than an electron experiment as a practical issue. More to write
soon.
Jay.
_________________________________
Cl.Massé
news: 3zKwwvTR...@charlesfrancis.wanadoo.co.uk
> I don't thick we have to sacrifice locality.
Yet, you do it since the very notion of locality implies the existence of a
topological structure of space-time.
> Each fundamental particle
> is sizeless, because size makes no sense without measurement.
That seems to me an arbitrary postulate, that I think is false, and above
all unnecessary. A particle may be detected at a single point, but it may
also be detected in a momentum eigenstate, when the detector has an inherent
spatial feature. The detector may be measured before the real measurement.
Actually, there has been an invisible paradigm shift between CM and QM. The
idea of singleness is no longer expressed in terms of a point, but in terms
of the projection postulate. The idea of indivisiveness replaced the one of
zero spatial extension. The paths integrals which come to mind is only
spuriously linked to point-like trajectories, they doesn't capture at all
the idea of indivisiveness, but rather address the propagation.
> It can
> only interact by being in contact with another particle, e.g. an
> electron is "in contact" with a photon at the time of emission. In a
> black hole we have lots of particles in contact, and occupying the same
> location.
The idea of contact comes rather from causality.
Returning to nonlocality, the condition for nonlocality not to be
inconsistent with causality is precisely the existence of a limiting speed.
Any experimental investigation of nonlocality can only be done in the
intersection of the line cones from two space-like separated points, where
it is not observable.
Cl.Massé
1173891438....@y80g2000hsf.googlegroups.com
> It is interesting to compare this with the EPR gedanken, the theorem
> by Jon Bell that says that it is possible to detect whether *any*
> hidden variable is at work, and the subsequent experiments by Aspect
> et al. which definitely ruled out the presence of a hidden variable of
> any kind in an EPR kind of experiment.
No, of *local* hidden variables, which isn't "any kind".
Oh No
>"Oh No" <No...@charlesfrancis.wanadoo.co.uk> a écrit dans le message de
>news: 3zKwwvTR...@charlesfrancis.wanadoo.co.uk
>
>> I don't thick we have to sacrifice locality.
>
>Yet, you do it since the very notion of locality implies the existence of a
>topological structure of space-time.
Yes, we have to sacrifice that notion of locality, but we can replace it
with a topological structure generated by particles themselves, in which
particles are in contact when they interact.
>
>> Each fundamental particle
>> is sizeless, because size makes no sense without measurement.
>
>That seems to me an arbitrary postulate, that I think is false, and above
>all unnecessary.
It is necessary to get around Parminedes paradox, and, in a more modern
context, in order to have a relativistic quantum theory, which requires
the locality condition of qed. To talk of size one needs a prior
geometry, but all we measure is interaction between matter and matter.
>A particle may be detected at a single point, but it may
>also be detected in a momentum eigenstate, when the detector has an inherent
>spatial feature. The detector may be measured before the real measurement.
This is a much more complicated form of measurement. Measurement of
momentum requires that we know something about changing positions. That
can't be done in a measurement at a single time.
>Actually, there has been an invisible paradigm shift between CM and QM. The
>idea of singleness is no longer expressed in terms of a point, but in terms
>of the projection postulate. The idea of indivisiveness replaced the one of
>zero spatial extension. The paths integrals which come to mind is only
>spuriously linked to point-like trajectories, they doesn't capture at all
>the idea of indivisiveness, but rather address the propagation.
Superposition corresponds to logical OR, not to logical AND. It means
the path is unknown (and only definable in terms of hypothetical
measurement) not that many paths are taken.
>
>> It can
>> only interact by being in contact with another particle, e.g. an
>> electron is "in contact" with a photon at the time of emission. In a
>> black hole we have lots of particles in contact, and occupying the same
>> location.
>
>The idea of contact comes rather from causality.
Not from causality, but from interaction.
>
>Returning to nonlocality, the condition for nonlocality not to be
>inconsistent with causality is precisely the existence of a limiting speed.
>Any experimental investigation of nonlocality can only be done in the
>intersection of the line cones from two space-like separated points, where
>it is not observable.
>
It is not even definable in such a case.
PD
> "PD" <TheDraperFam...@gmail.com> wrote in message
It really makes no difference between one particle or two. The
entanglement of the two-particle state reflects the fact that it is a
*single* (two-particle) wavefunction. The collapse of that one
wavefunction in the EPR/Aspect-style experiment is what gives the
appearance of superluminal communication, which is precisely what E
and P and R were worried about and which you appear to be worried
about all over again.
Your single-particle experiment still reflects the fact that a single
wavefunction is incident on both slits in the Young-style experiment.
The fact that the wavefunction is a single-particle wavefunction is
not particularly fundamental. The collapse of the wavefunction occurs
in the same way.
PD
Tom
photon thru a slit is that they talk about the slit and ignore the
edges of the slit. At the edges are atoms, the atoms have different
energy levels. Electrons or photons can pass through the atoms at the
edge and be scattered in different directions depending on which
energy level they passed through. I would say that the patterns are
not due to interference and the single photon patterns prove that.
Jay R. Yablon
implementing this experiment beyond "pedagogical gedanken."
How tightly can we cause a photon or electron to be emitted "on demand"?
The last-minute changing of the slits to try to "fool" the quantum
depends upon knowing with some precision when the quantum is emitted.
This means either:
a) a "trigger" sending a first signal to the quantum emitter which says
"emit one quantum," and knowing with some reliability when that quantum
will be released, with the trigger simultaneously sending a second
signal to the slits saying "change." The trigger location and the
signal paths are carefully chosen so the signals reach the emitter and
the slits at just the right relative times, within whatever tolerances
we have.
or:
b) knowing "when" the quantum was emitted, without disturbing the
emission, so we can send a properly-timed signal to the slits. For
photons, this is a problem, because the signal to change the slits has
to beat the photon to the slits.
It is also clear to me that if the apparatus is measured in feet /
meters, the slits need to change their state in picoseconds to
nanoseconds. Gigahertz to terahertz electro-optical or purely-optical
switches / transistors would seen to be required.
Jay.
Materion
That's a very clear presentation of a Broglian/Bohmian model. Bohmian
models all have in common your points 1-13. Or put in John Bell's
words: "This idea seems to me so natural and simple, to resolve the
wave-particle dilemma in such a clear and ordinary way, that it is a
great mystery to me that it was so generally ignored" - complete
citation at the end of this post. At points 14 and 15, you specify
your idea in some form of Casimir effect comparing a slit to a mirror.
Interesting idea. The fact is that in both cases (Casimir and double
slit), we have two static sources of a quantum electromagnetic field
of same frequency, which yield standing interference between
travelling waves. In the Bohmian approach, the active information of
the waves guides the motion of the particle. So yes, that works with
the Casimir effect and with Young's experiment.
In my opinion, there are two main reasons that Bohmian models are "so
generally ignored":
1. the results of boolean entanglement experiments, which rule out
*local* additional variable models assuming fair sampling of the
detected particles.
2. Bohmian models generally stay at quantum level, while there is no
restriction to specify Bohmian models with ordinary macroscopic
objects.
I believe that developing Bohmian models with ordinary objects will
help to make headway toward a "better", more comprehensive,
explanation of quantum effects.
We could for example think of fast rotating needles that are shot
toward a wall with two slits. Before and after the wall, let there be
an all pervading dense cloud of similar (non- or slowly rotating)
needles. Due to its rotation, the projectile needle constantly
generates shock waves in the cloud. The shock wave frequency and the
rotation frequency of the projectile needle are in phase. The motion
of the projectile will therefore interfere with the shock wave at the
other side of the slits. If the detector at the far end is tuned to
detect only needles with high rotation frequency, we obtain an
interference pattern.
David Bohm, in his book 'the Undivided Universe' (coauthor BJ Hiley),
suggested another model where radio waves guide the motion of
macroscopic objects. Such models have the advantage to visualize
physically what's happening at the quantum level.
Regards.
--
Arjen Dijksman
--------------
J.S.Bell, "Six possible worlds of quantum mechanics", 1986:
"While the founding fathers agonized over the question
'particle' or 'wave'
de Broglie in 1925 proposed the obvious answer
'particle' and 'wave'.
Is it not clear from the smallness of the scintillation on the screen
that we have to do with a particle? And is it not clear, from the
diffraction and interference patterns, that the motion of the particle
is directed by a wave?
De Broglie showed in detail how the motion of a particle, passing
through just one of two holes in screen, could be influenced by waves
propagating through both holes. And so influenced that the particle
does not go where the waves cancel out, but is attracted to where they
cooperate. This idea seems to me so natural and simple, to resolve the
wave-particle dilemma in such a clear and ordinary way, that it is a
great mystery to me that it was so generally ignored."
Ray Tomes
...
> 3) If we had never known of Young's experiments, and if the first
> double slit experiments ever performed had been performed one electron
> or photon at a time, we would have described light as a series of
My preference is to do the opposite. To consider light as waves only,
as continuous developments of Maxwell's equations. The particle
nature does *not* belong to light. It belongs to the exchange of
energy between light and matter. That is because matter is standing
waves of e/m and has only certain discrete oscillation modes.
I have written a simple analogy which I call the "drip model of light"
http://www.cyclesresearchinstitute.org/wsm/FSMN_WSM_RT.pdf
I do not find that there is anything that is mysterious in QM once
this point of view is adopted. I was able to correctly predict that
a single quantum of emitted light would be detected as a poisson
distribution from this idea. A bunch of physicists told me that I
was wrong, but then I was informed by someone who was more
knowledgeable that the experiment had been done in the 1950s
by Hanbury-Brown and Twiss and that my prediction was correct.
Regards
Ray Tomes
Note. My ISP still does not have this group available so I must use
a web interface which I do not like. If you reply to me, then please
CC me a copy by email and increase my chances of responding.
Thanks. ray(at)tomes(dot)biz
harry
"Ray Tomes" <r...@tomes.biz> wrote in message
news:1177844569.2...@n59g2000hsh.googlegroups.com...
> On Mar 12, 4:43 pm, "Jay R. Yablon" <jyab...@nycap.rr.com> wrote:
> ...
>> 3) If we had never known of Young's experiments, and if the first
>> double slit experiments ever performed had been performed one electron
>> or photon at a time, we would have described light as a series of
>> particles which probabilistically build up into the pattern ...
>
> My preference is to do the opposite. To consider light as waves only,
> as continuous developments of Maxwell's equations. The particle
> nature does *not* belong to light. It belongs to the exchange of
> energy between light and matter. That is because matter is standing
> waves of e/m and has only certain discrete oscillation modes.
>
> I have written a simple analogy which I call the "drip model of light"
> http://www.cyclesresearchinstitute.org/wsm/FSMN_WSM_RT.pdf
I think that there are some simplifications that make it so-so, but then,
you call it yourself a "simple analogy". It surely may help as illustration
to convey an idea. Another model that struck me yesterday is that of a row
of balls on strings, such as used to illustrate momentum transfer. We can
let one or two balls collide with the row of balls (excite one or two
quanta); after propagating in the form of a 1D sound wave, one or two
excited balls reappear at the other end. That is fascinating, but only
magical if one formulates it as such.
What I appreciate most of all, is that what Caroline had tried to make clear
to me but in vain, finally "clicked" with your illustration of selection of
information - thanks!
I think that I now understand the essence of the argument that "spooky
action at-a-distance" only exists in the minds of "some" physicists. Note
however, that "some" is more likely *most*, because of the way the theory is
curently formulated and presented. Perhaps that new wave models (such as
string-net) will be able to help out. :-)
And now that I finally "get" it, I'll need to read the theory about the Bell
problem again with new eyes, in order to see if you may be right.
Best regards,
Harald
maxwell
> Dear SPF friends:
>
> With this post, I would like to initiate a group discussion of the
> double slit experiment, when it is performed one quantum at a time. The
> goal is to see if we can make any headway toward a "better," for
> "physical" explanation of this experiment, than any which has been
> developed at present.
Good topic & discussion, Jay. I have copied over a contribution from
another thread that might help here, as I believe a completely
'classical' particle theory can explain the physics of 'interference'.
{begin.quote}
One does NOT need a wave theory to understand Maxwell's (Heaviside's)
Equations. Any space-time disturbance that is based only on their 4D
separation will generate these results if the ratio of space to time
is constant in the
asynchronicity effect. Waves are just the Fourier interpretation of
any space-time periodicity, including propagated pulses. It is only
by assuming that these are media-carried waves that the common
intuition
(analogue to ocean waves) is mystified.
Secondly, there are pure particle explanations (see Alfred Lande's
work e.g. "QM", "New Foundations of QM") to explain the double-slit
experimental results but they involve recognizing that the WALLS of
the slits consist of milliards of electrons that participate in the
interaction between the electrons of the 'hot' source & those of the
target screen (if we are observing 'light') or directly if the
electrons pass through only one slit. The absence of the material
corresponding to the 'presence' of the second slit presents the
interacting electrons with a completely different context; but QM
ignores the context by working only with aggregate statistical
results on a 'single' electron. The world is vastly more complex than
our simplified
mathematical models.
{End.Quote}
The major problem todate is that physics has never solved the three-
body problem. It has simplified the two-body to an equivalent one-
body problem. We have made good progress statistically with the N-
body problem, where N >> 1. But until we begin to focus on the
interaction itself (the physics behind Maxwellian EM) I think we will
stay stuck in the swamp.
harry
"harry" <harald.vanlin...@epfl.ch> wrote in message
news:1177926...@sicinfo3.epfl.ch...
I now looked into this again, and found back a link to "quantum erasure"
experiments:
http://grad.physics.sunysb.edu/~amarch/
Surely such experiments cannot be explained with selection of information
that we have at our disposition.
At the same time, apparently such a mechanism cannot be used to transmit
Morse code faster than light; I suppose that the effect of changing the
polarizer changes the pattern as fast as a light signal (if a photon event
occurs at that time). Thus that kind of "action-at-a-distance" is not as
spooky as the kind in which instantaneous effects are claimed. And even such
phenomena are probably to be interpreted in a similar way (see for example
http://www.sciencemag.org/cgi/content/full/287/5460/1909 ).
Anyway, I like to hear your comment on quantum erasure - do you also claim
that there is nothing mysterious about that?
Regards,
Harald
Cl.Massé
news: 1177926...@sicinfo3.epfl.ch
> Another model that struck me yesterday is
> that of a row of balls on strings, such as used to illustrate momentum
> transfer. We can let one or two balls collide with the row of balls
> (excite one or two quanta); after propagating in the form of a 1D sound
> wave, one or two excited balls reappear at the other end. That is
> fascinating, but only magical if one formulates it as such.
That is a discrete model of the propagation of a classical wave. Nothing
quantic, even if in a book on quantum mechanics (Berkeley lectures?) It is
merely the propagation of an impulsion, such that can be observed in a
continuous medium like a clothes line. It isn't a quanta, for that you have
to quantize the motion of the balls.
> I think that I now understand the essence of the argument that "spooky
> action at-a-distance" only exists in the minds of "some" physicists.
That action occur at a speed lesser than the light speed, like do an
acoustic wave. That isn't what is designed by "spooky action
at-a-distance". A more elaborate model is necessary to make it appear.
harry
"Cl.Massé" <ret...@contactprospect.com> wrote in message
news:4637855c$0$28776$426a...@news.free.fr...
> "harry" <harald.vanlin...@epfl.ch> a écrit dans le message de
> news: 1177926...@sicinfo3.epfl.ch
>
>> Another model that struck me yesterday is
>> that of a row of balls on strings, such as used to illustrate momentum
>> transfer. We can let one or two balls collide with the row of balls
>> (excite one or two quanta); after propagating in the form of a 1D sound
>> wave, one or two excited balls reappear at the other end. That is
>> fascinating, but only magical if one formulates it as such.
>
> That is a discrete model of the propagation of a classical wave. Nothing
> quantic, even if in a book on quantum mechanics (Berkeley lectures?) It
> is
> merely the propagation of an impulsion, such that can be observed in a
> continuous medium like a clothes line. It isn't a quanta, for that you
> have
> to quantize the motion of the balls.
There I reacted to the illustration of wave-particle duality in his
hyperlink, and I gave one of mine. However, the balls in my simple
illustration are certainly quantisized - the impulse of 1 ball on one end
results in exactly 1 ball coming out at the other end. That is not at all
like a classical wave in a clothes line.
>> I think that I now understand the essence of the argument that "spooky
>> action at-a-distance" only exists in the minds of "some" physicists.
>
> That action occur at a speed lesser than the light speed, like do an
> acoustic wave.
Which action? I referred to his hyperlinked explanation attempt of spooky
action at-a-distance. But see also my later comment.
> That isn't what is designed by "spooky action
> at-a-distance". A more elaborate model is necessary to make it appear.
The model that I brought up in that context is string-net theory, by now I
have seen a few chapters of it. How do you know that that won't be able to
come up with the answer?
Regards,
Harald
======================================= MODERATOR'S COMMENT:
The balls are discrete, not quantized, for the latter read Einstein's paper 1907 on the theory of heat
Cl.Massé
>> quantic, even if in a book on quantum mechanics (Berkeley lectures?) It
>> is
>> merely the propagation of an impulsion, such that can be observed in a
>> continuous medium like a clothes line. It isn't a quanta, for that you
>> have to quantize the motion of the balls.
"harry" <harald.vanlin...@epfl.ch> a écrit dans le message de
news: 1178092...@sicinfo3.epfl.ch
> There I reacted to the illustration of wave-particle duality in his
> hyperlink, and I gave one of mine. However, the balls in my simple
> illustration are certainly quantisized - the impulse of 1 ball on one end
> results in exactly 1 ball coming out at the other end. That is not at all
> like a classical wave in a clothes line.
You mean, that is *exactly* like a classical wave in a clothes line. 1
impulse on one end = 1 impulse at the other end. Make the number of ball
tend to infinity for a fixed length and it is what you get. You'll find
many of that kind of demysitification of QM, most are false. The balls are
described by their position, not by a wave function of their position,
therefore their motion isn't quantized.
>> That action occur at a speed lesser than the light speed, like do an
>> acoustic wave.
> Which action? I referred to his hyperlinked explanation attempt of spooky
> action at-a-distance. But see also my later comment.
>> That isn't what is designed by "spooky action
>> at-a-distance". A more elaborate model is necessary to make it appear.
> The model that I brought up in that context is string-net theory, by now I
> have seen a few chapters of it. How do you know that that won't be able to
> come up with the answer?
Because the "spooky action at-a-distance" occurs when there is a correlation
between two states. You can have it only from an already correlated state,
what isn't a classical impulse.
harry
wrote:
> "Cl.Massé" <ret...@contactprospect.com> wrote in message
>
> news:4637855c$0$28776$426a...@news.free.fr...
>
>
>
> >news: 1177926652_2__BEGIN_MASK_n#9g02mG7!__...__END_MASK_i?a63jfAD$z...@sicinfo3.epfl.ch
Good precision - indeed in this illustration the balls stand for
quantisized mass. Dropping them from a discrete heights would even
stand for quantisized energy levels, which will be more difficult to
achieve with the waterdrop example that I compared it to. Anyway, an
illustration doesn't need to match completely in order to make
something clear.
harry
>>> That is a discrete model of the propagation of a classical wave.
>>> Nothing
>>> quantic, even if in a book on quantum mechanics (Berkeley lectures?) It
>>> is
>>> merely the propagation of an impulsion, such that can be observed in a
>>> continuous medium like a clothes line. It isn't a quanta, for that you
>>> have to quantize the motion of the balls.
>
> "harry" <harald.vanlin...@epfl.ch> a écrit dans le message de
> news: 1178092...@sicinfo3.epfl.ch
>
>> There I reacted to the illustration of wave-particle duality in his
>> hyperlink, and I gave one of mine. However, the balls in my simple
>> illustration are certainly quantisized - the impulse of 1 ball on one end
>> results in exactly 1 ball coming out at the other end. That is not at all
>> like a classical wave in a clothes line.
>
> You mean, that is *exactly* like a classical wave in a clothes line. 1
> impulse on one end = 1 impulse at the other end.
Your clothes line doesn't transmit a quantisized mass unit - thus it
completely misses the point.
> Make the number of ball
> tend to infinity for a fixed length and it is what you get.
The count of balls that is coming out is equal to the count of balls that
comes in, independent of the number of balls that transmit the wave.
> You'll find
> many of that kind of demysitification of QM, most are false. The balls
> are
> described by their position, not by a wave function of their position,
> therefore their motion isn't quantized.
Ok, now I see the reason for the misunderstanding: I did not claim or
suggest that the motion is quantisized. However, of course this can be done
if one wants to refine the illustration - but such is not required to
illustrate how our distinction of particles and waves may be artificial.
>>> That action occur at a speed lesser than the light speed, like do an
>>> acoustic wave.
>
>> Which action? I referred to his hyperlinked explanation attempt of spooky
>> action at-a-distance. But see also my later comment.
>
>>> That isn't what is designed by "spooky action
>>> at-a-distance".
What do you mean with "that"? Anyway, it's more useful if you add to my
later comment on his explanation.
>>> A more elaborate model is necessary to make it appear.
>
>> The model that I brought up in that context is string-net theory, by now
>> I
>> have seen a few chapters of it. How do you know that that won't be able
>> to
>> come up with the answer?
>
> Because the "spooky action at-a-distance" occurs when there is a
> correlation
> between two states. You can have it only from an already correlated
> state,
> what isn't a classical impulse.
I'm afraid that "classical impulse" is a too poor description of string-net
theory.
Harald
======================================= MODERATOR'S COMMENT:
Dear all, for sake of that all readers can follow this thread I would like to ask you to make your points more clear
harry
[...]
> ======================================= MODERATOR'S COMMENT: Dear all, for
> sake of that all readers can follow this thread I would like to ask you to
> make your points more clear
To put this back on track (a side-track really), here a summary:
Commenting on Jay's suggestion to see wave-particle-duality "as a series of
particles which probabilistically build up into the pattern ..." (Jay's
point 3), Ray Thomes put forward the view that "That is because matter is
standing waves of e/m and has only certain discrete oscillation modes" and
he wrote:
"I have written a simple analogy which I call the "drip model of light"
http://www.cyclesresearchinstitute.org/wsm/FSMN_WSM_RT.pdf
I do not find that there is anything that is mysterious in QM once
this point of view is adopted. "
I commented on that analogy by adding a similar illustration of a row of
balls on strings. Further, I found that in that same article he explained
rather well the information-selection argument concerning EPR (similar to
the loophole argument), and I wondered if an advanced theory such as
string-net might be able to explain "spooky action at-a-distance". Clmasse
had some issues with that; but in my opinion those were beside the point. In
a follow-up commentary, I brought up the "quantum erasure" experiments, and
asked Ray if for him there is also nothing "spooky" about that - I suppose
that "information-selection" does not explain the appearance or
disappearance of fringes elsewhere.
Harald