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From: Daryl McCullough on 27 Jul 2010 10:50
Hayek says...

>But suppose that someone finds a way to send
>instantaneous messages, by means of Quantum effects.

As far as anyone knows, the speed of light is the upper
bound for any transmission of signals. Quantum effects
don't change that.

Sure, it's possible that all our physics is wrong, and
that instantaneous effects are possible. But there is
no reason to believe that.

>This is not even far fetched, as the Aspect experiment,
>now even some 10 miles apart, indicate that entangled
>photons seem to send information about their
>polarization across that distance.

Entanglement does *not* allow faster-than-light communication.

>Suppose we have instant messaging, what about relativity
>would be wrong?

If a message is instantaneous in one frame, then (if
relativity is right) in a different frame, the message
arrives before it is sent.

The theory of relativity, together with the assumption that
instantaneous communication is possible, leads to the conclusion
that it is possible to send a message into one's own past.

--
Daryl McCullough
Ithaca, NY

From: PD on 27 Jul 2010 10:50
On Jul 27, 9:37 am, Hayek <haye...(a)nospam.xs4all.nl> wrote:
> PD wrote:
> > On Jul 27, 6:02 am, Hayek <haye...(a)nospam.xs4all.nl> wrote:
>
> >> With instantaneous communication, and a correct
> >> definition of time, and there is no such thing anymore
> >> as relativity of simultaneity.
>
> > I don't know why a definition of time would be more correct
>
> Any definition of time will be welcome. Then we can
> argue the pros and cons.
>
> > if you
> > presuppose a phenomenon that is specifically and unilaterally excluded
> > in our universe.
>
> Hold your horses. Are you certain this does not happen
> under uncertainty ?

I don't see any evidence whatsoever of ftl communication under any
aspect of quantum mechanics.

There is indeed evidence for lack of strict time-ordering, but that is
different than ftl communication.

Nor did I say that we had time all figured out (see Tegmark's list
below). That doesn't mean that we haven't figured out ANYTHING about
time.

>
> > It might be conceptually appealing to you, but it
> > wouldn't have any bearing on time AS IT APPLIES in nature as we
> > observe it.
>
> I beg to differ.
>
> Look at what questions the FQxi (http://www.fqxi.org)
> has put forward in order to obtain a grant :
>
> 1 Can physics establish or deny the flow of time?
>
> 2 If the flow of time is an illusion, how do we explain
> this illusion?
>
> 3 Are the laws of physics time-symmetric or
> time-reversible?
> 3 If not, how does one explain the time symmetry of some
> physical laws and the asymmetry of others?
>
> 4What do the theory of relativity and quantum mechanics
> (QM) respectively tell us about
>  the nature of time and time travel?
> 5 How do we reconcile their see-mingly inconsistent
> conceptions of time?
> 6 Is the nature of time intrinsically different from
> that of space?
> 7 Can physical time be infinite?
> 8  Is the universe a static “block” universe?
> 9  Does the big bang (at least partially) explain the
> entropic arrow of time?
> 10 Is the nature of time intrinsically different from
> that of space?
> 11 Why?
> 12 Are there many space-time branches or timelines in
> addition to our own?
> 13 Do these theories provide us with inconsistent
> con-ceptions of time?
> 14 If we could experimentally confirm or discard any of
> the key specific interpretations of QM or classes of
> interpretation (such as collapse accounts), would we
> gain insight on the problems of time?
> 15 Can QM explain the beginning of time?
> 16 Is space-time itself quantized? If so, what does it
> mean?
> 17 Can we, by way of experiments employing different
> reference frames, experimentally confirm the existence
> of anything such as the need for preferred foliations,
> inconsistent histories, advanced action, evolving
> spacetime, etc., that argues against the block-universe
> interpretation of relativity theory?
> 18  Does non-locality in QM give us good reason to
> modify relativity?
> 19  Are there new QM experiments (thought or otherwise)
> involving weak values, pre- and post- selection,   etc.,
> that bear on the problems of time? For example, are
> there such experiments that are best interpreted as
> requiring “BCQM” or advanced action?
> 20 Are there any specific accounts of time-symmetric
> quantum mechanics, such as truly new time-symmetric
> dynamics, that bear on the problems at hand, suggest new
> predic-tions, etc.?
> 21 Is the Everett-Wallace-Saunders interpretation of QM
> truly local and consistent with “M4” and “blockworld”?
> 22 If so, how does this or any other view which takes
> the wave function as fundamental (such as GRW) recover
> M4 and relativity?
> 23  How many spatial dimensions are there? Can this
> question be resolved empirically or experimentally?
> 24 Can there be more than one temporal dimension?
> 25  Is the Tumulka-GRW interpretation truly covariant,
> and can it be extended to cases with interactions?
> 26 Does Bohmian mechanics require a preferred frame, and
> if so does that undermine the Bohmian interpretation of
> QM or special relativity?
> 27 How can time be recovered from the timeless
> Wheeler-Dewitt equation?  Must we modify the equation?
> Or replace it altogether?
>
> UNQUOTE
>
> Uwe Hayek.
>
> --
> We are fast approaching the stage of the ultimate
> inversion : the stage where the government is free to do
> anything it pleases, while the citizens may act only by
> permission; which is the stage of the darkest periods of
> human history. -- Ayn Rand
>
> I predict future happiness for Americans if they can
> prevent the government from wasting the labors of the
> people under the pretense of taking care of them. --
> Thomas Jefferson.
>
> Socialism is a philosophy of failure, the creed of
> ignorance, and the gospel of envy, its inherent virtue
> is the equal sharing of misery. -- Winston Churchill.

From: Daryl McCullough on 27 Jul 2010 10:55
Hayek says...

>Then, what is time ?
>
>To me, time emerges from motion.

That doesn't make sense. How do you define "motion"?
I would define motion as "change of position as a function
of time".

>And motion is influenced by inertia. If the inertia is higher
>then the quartz in your clock moves slower. You do not notice it,
>but because at 37 centigrade body temperature, the
>molecules in your body also move slower. I claim that
>the only difference between inertial frames with
>different gamma is the strength of the inertia.

gamma is not associated with an inertial frame, it is
associated with a *pair* of inertial frames. Gamma, like
velocity, is relative.

--
Daryl McCullough
Ithaca, NY

From: PD on 27 Jul 2010 10:58
On Jul 27, 9:25 am, Hayek <haye...(a)nospam.xs4all.nl> wrote:
> Daryl McCullough wrote:
> > Hayek says...
>
> >> I find a lot of flaws in these "gedanken". For instance,
> >> Einstein assumes that the event only takes place if you
> >> see the lightflash of the event in your frame of reference.
>
> > He makes no such assumption.
>
> >> Light to me, is only an imperfect carrier of
> >> information, just as sound is.
>
> >> With instantaneous communication, and a correct
> >> definition of time, and there is no such thing anymore
> >> as relativity of simultaneity.
>
> > That's exactly right. Relativity of simultaneity is
> > a consequence of there being an upper bound to communication
> > speed. If there is no upper bound, then relativity is wrong.
>
> Brilliant remark.
>
> But suppose that someone finds a way to send
> instantaneous messages, by means of Quantum effects.
> This is not even far fetched, as the Aspect experiment,
> now even some 10 miles apart, indicate that entangled
> photons seem to send information about their
> polarization across that distance.
> But let's not start that discussion again.

I do think it's worth starting that discussion again.

There is a DISTINCT difference between ftl communication and quantum
entanglement.

FTL communication in a two-particle system DEMANDS the principle of
locality, which says that two particles in a state are separable in
their properties and that any change in one particle cannot influence
the state of the other particle except for a signal transmission from
one to the other. An Aspect-like result would then imply FTL
communication.

Quantum entanglement in a two-particle system DISAVOWS the principle
of locality, and says that there things as SINGLE quantum state with
two particles, so that what is measured are not the properties of
independent particles but of the single STATE. In such case, there is
no FTL communication implied whatsoever.

The hyperbolic structure of spacetime, which by the way has enormous
implications which all agree with experiment, rules out FTL.
Furthermore, Bell's theorem gives a *quantifiable* measurement in
Aspect-like experiments (beyond the simple correlation you mention)
that tests whether there is a hidden local variable in play. The
measured results show that quantum mechanics is favored over local
hidden variable theories of just about any class.

>
> Suppose we have instant messaging, what about relativity
> would be wrong ? Time would still dilate, rods shrink,
> and even RoS would still apply if you only used light as
>   communication.

No. Rods do not shrink because of light communication. You can
replicate the results of relativity without relying on light for the
communication at all, or at best in a secondary way where it could not
influence the results in the same way.

>
> Ok, mutual time dilation would have to go, but that was
> not of much use anyway, SR would look more like LET, but
> what was the difference anyway ? For one there was no
> absolute reference, and for the other it was not measurable.
>
> And since instant messaging would be a non-local
> phenomenon, it would still hold true that the laws of
> physics remain locally the same.
>
> It would be just "a next step" for physics, all the old
> physics remaining correct, just in some cases some
> blanks were filled in, just as Einstein replaced Newton.
>
> And then you could also usenet-chat with alien morons,
> or were we doing that already ?
>
> Uwe Hayek.
>
> --
> We are fast approaching the stage of the ultimate
> inversion : the stage where the government is free to do
> anything it pleases, while the citizens may act only by
> permission; which is the stage of the darkest periods of
> human history. -- Ayn Rand
>
> I predict future happiness for Americans if they can
> prevent the government from wasting the labors of the
> people under the pretense of taking care of them. --
> Thomas Jefferson.
>
> Socialism is a philosophy of failure, the creed of
> ignorance, and the gospel of envy, its inherent virtue
> is the equal sharing of misery. -- Winston Churchill.- Hide quoted text -
>
> - Show quoted text -

From: Hayek on 27 Jul 2010 11:03
Daryl McCullough wrote:
> Hayek says...
>
>> But suppose that someone finds a way to send
>> instantaneous messages, by means of Quantum effects.
>
> As far as anyone knows, the speed of light is the upper
> bound for any transmission of signals. Quantum effects
> don't change that.
>
> Sure, it's possible that all our physics is wrong, and
> that instantaneous effects are possible. But there is
> no reason to believe that.
>
>> This is not even far fetched, as the Aspect experiment,
>> now even some 10 miles apart, indicate that entangled
>> photons seem to send information about their
>> polarization across that distance.
>
> Entanglement does *not* allow faster-than-light communication.

You mean "useful communication for us". But the
polarization of the photon gets communicated.
I asked not to start that discussion again.

>
>> Suppose we have instant messaging, what about relativity
>> would be wrong?
>
> If a message is instantaneous in one frame, then (if
> relativity is right) in a different frame, the message
> arrives before it is sent.

In your interpretation of "time" maybe, but not in mine.

That is why it is important to have a correct knowledge
of time.

> The theory of relativity, together with the assumption that
> instantaneous communication is possible, leads to the conclusion
> that it is possible to send a message into one's own past.

What makes you say that ?

In my interpretation of time, the past no longer exists,
so I do not see how that would be accomplished.

Uwe Hayek.



--
We are fast approaching the stage of the ultimate
inversion : the stage where the government is free to do
anything it pleases, while the citizens may act only by
permission; which is the stage of the darkest periods of
human history. -- Ayn Rand

I predict future happiness for Americans if they can
prevent the government from wasting the labors of the
people under the pretense of taking care of them. --
Thomas Jefferson.

Socialism is a philosophy of failure, the creed of
ignorance, and the gospel of envy, its inherent virtue
is the equal sharing of misery. -- Winston Churchill.
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