It's clear that DK's scheme won't work - nor will any scheme that is based on unitary linear orthodox quantum theory using orthogonal base states.
However, concerning Valentini's, Josephson, Weinberg, Stapp & my different & independent from from DK's approaches: while the trace operation to get expectation values of observables on quantum density matrices is invariant under unitary transformations of the base states which preserve orthogonality, that is not true for the transformation from an orthogonal Fock basis to the non-orthogonal Glauber coherent state basis, which is clearly a non-unitary transformation that is OUTSIDE the domain of validity of orthodox quantum theory. I think many Pundits have missed this point?
Hawking's former assistant Bernard Carr spells this out clearly in Can Psychical Research Bridge the Gulf Between Matter and Mind?" Bernard Carr Proceedings of the Society for Psychical Research, Vol 59 Part 221 June 2008
Begin forwarded message:
From: nick herbert <
Subject: Re: AW: AW: More on the |0>|0> term
Date: June 14, 2013 11:14:57 AM PDT
To: Suda Martin <
Thank you, Martin.
I finally get it.
My confusion lay in the attribution of the short calculation below.
I thought this calculation (which leads to rA) was due to Gerry.
Instead it is a calculation done by Gerry but attributed to DK.
It was not a calculation that DK ever carried out but
arose from Gerry taking Gerry's FULL CALCULATION,
applying the Kalamidas approximation
and getting an incorrect result.
The correct result is Zero
on which you and Gerry agree.
So if Kalamidas would have carried out the calculation this way
he would have gotten an incorrect answer.
I hope I have now understood the situation correctly.
But Kalamidas did not carry out the calculation that Gerry displays.
DK did not start out with the FULL CALCULATION and then approximate.
DK starts with an approximation and then calculates.
DK starts with an approximation and carries out a series of steps which all seem to be valid
but whose conclusion is preposterous. Furthermore the approximation (weak coherent states)
is an approximation used in dozens of laboratories by serious quantum opticians without
as far as I am aware leading to preposterous or impossible conclusions.
Therefore it seems to me that the calculation below is another nail in the Kalamidas coffin, BUT
THE BEAST IS STILL ALIVE.
1. No one yet has started with Kalamidas's (approximate) assumptions, and discovered a mistake in his chain of logic.
2. No one yet has started with Kalamidas's (approximate) assumptions, followed a correct chain of logic and shown that FTL signaling does not happen.
Martin Suda came the closest to carrying out problem #2. He started with the Kalamidas (approximation) assumptions and decisively proved that all FTL terms are zero. But Martin's proof contains an unphysical |0>|0> term that mars his triumph.
I am certain that the Kalamidas claim is wrong. The FULL CALCULATION refutations of Ghirardi, Howell and Gerry are pretty substantial coffin nails. But unless I am blind there seems still something missing from a clean and definitive refutation of the Kalamidas claim. See problems #1 and #2 above.
I do not think that Nick is being stubborn or petty in continuing to bring these problems to your attentions. I should think it would be a matter of professional pride to be able to bring this matter to a clean and unambiguous conclusion by refuting Kalamidas on his own terms.
Thank you all for participating in this adventure whatever your opinions.
Nick Herbert
On Jun 14, 2013, at 3:29 AM, Suda Martin wrote:
Nick,
Thank you for comments!
I would still like to explain my short considerations below a bit more precisely, anyway. I feel there was perhaps something unclear as regards my email (12th June), because you wrote "you were confused".
I only considered the following:
DK disclosed a calculation (see attachment) which is completely wrong because he made a mathematical limit (see first line, where he omitted the term ra^{+}_{a3}) which is absolutely not justifiable here (just as CG mentioned, see below) because both parts are equally important if you make the expectation value properly. If you take both parts you get exactly zero: alpha^{*}(tr^{*}+rt^{*})=0.
So one does not obtain a quantity like (r alpha)^{*}.
That’s all. There is absolutely no discrepancy between me and CG.
Nice regards,
Martin
-----Ursprüngliche Nachricht-----
Von: nick herbert [mailto:
Gesendet: Mittwoch, 12. Juni 2013 23:33
Betreff: Re: AW: More on the |0>|0> term
"And again, the notion that an alleged approximate calculation (I say "alleged" because as with everything else there are correct and incorrect approximate calculations) based on a weak signal coherent state somehow trumps an exact computation valid for any value of the coherent state parameter, is, well, just insane. If you want to see where things go wrong just take more terms in the series expansions. Add up enough terms and, viola, no effect! One can't get much more specific than that." --Christopher Gerry
Actually, Chris, one can get much more specific than that by explicitly displaying the Correct Approximation Scheme (CAS) and showing term by term than Alice's interference vanishes (to the proper order of approximation).
Absent a correct CAS and its refutation these general claims are little more than handwaving.
Produce a CAS.
Refute it.
Is anyone up to this new Kalamidas challenge?
Or does everyone on this list except me
consider deriving a CAS a waste of time?
Nick Herbert
On Jun 12, 2013, at 2:03 PM, CHRISTOPHER GERRY wrote:
We are both right: the two terms cancel each other out! That the
whole expectation value is zero is actually exactly what's in our
paper's Eq. 9. This happens because the reciprocity relations must
hold. That Kalamidas thought (or maybe even still thinks) his
calculation is correct, is at the heart of the matter, that is, that
he is either unable to do the calculations or that he can do them but
chooses not too because they don't get him where he wants to go.
The Kalamidas scheme will not work not work on the basis of general
principles as we showed in the first part of our paper (see also
Ghirardi's paper).
And again, the notion that an alleged approximate calculation (I say
"alleged" because as with everything else there are correct and
incorrect approximate calculations) based on a weak signal coherent
state somehow trumps an exact computation valid for any value of the
coherent state parameter, is, well, just insane. If you want to see
where things go wrong just take more terms in the series expansions.
Add up enough terms and, viola, no effect! One can't get much more
specific than that.
Christopher C. Gerry
Professor of Physics
Lehman College
The City University of New York
718-960-8444
---- Original message ----
Date: Wed, 12 Jun 2013 12:28:16 -0700
From: nick herbert <
Subject: Re: AW: More on the |0>|0> term
To: Suda Martin
All--
Excuse me for being confused.
Gerry refutes Kalamidas by showing that an omitted term is large.
Suda refutes Kalamidas by showing that the same term is identically
zero.
What am I missing here?
I wish to say that I accept the general proofs. Kalamidas's scheme
will not work as claimed.
That is the bottom line. So if the general proofs say FTL will fail
for full calculation, then it will certainly fail for approximations.
The "weak coherent state" is a common approximation made in quantum
optics. And dozens of experiments have been correctly described using
this approximation. So it should be a simple matter to show if one
uses Kalamidas's approximation, that FTL terms vanish to the
appropriate level of approximation. If this did not happen we would
not be able to trust the results of approximation schemes not
involving FTL claims.
Gerry's criticism is that Kalamidas's scheme is simply WRONG--that he
has thrown away terms DK regards as small.
But in fact they are large. Therefore the scheme is flawed from the
outset.
If Gerry is correct, then it seems appropriate to ask: Is there a
CORRECT WAY of formulating the Kalamidas scheme using the "weak
coherent state" approximation, where it can be explicitly shown that
this correct scheme utterly fails?
It seems to me that there are still some loose ends in this Kalamidas
affair, if not a thorn in the side, at least an unscratched itch.
It seems to me that closure might be obtained. And the Kalamidas
affair properly put to rest if everyone can agree that 1. DK has
improperly treated his approximations; 2. Using the CORRECT
APPROXIMATION SCHEME, the scheme abjectly fails just as the exact
calculation says it must.
Why should it be so difficult to construct a correct description of
the Kalamidas proposal, with CORRECT APPROXIMATIONS, and show that it
fails to work as claimed?
AS seen from the Ghirardi review, there are really not that many
serious FTL proposals in existence. And each one teaches us
something-- mostly about some simple mistakes one should not make when thinking
about quantum systems. Since these proposals are so few, it is really
not a waste of time to consider them in great detail, so we can learn
to avoid the mistakes that sloppy thinking about QM brings about.
When Ghirardi considers the Kalamidas scheme in his review, I would
consider it less than adequate if he did not include the following
information:
1. Kalamidas's scheme is WRONG because he treats approximations
incorrectly.
2. When we treat the approximations correctly, the scheme fails, just
as the general proofs say it must.
Gerry has provided the first part of this information. What is
seriously lacking here is some smart person providing the second
part.
Nick Herbert
On Jun 12, 2013, at 8:50 AM, Suda Martin wrote:
Dear all,
Yes, if one calculates precisely the Kalamidas - expression given in
the attachment of the email of CG one obtains exactly
alpha^{*}(tr^{*}+rt^{*})=0
due to the Stokes-relation of beam splitters. No approximations are
necessary. So, I am astonished about the sloppy calculations of
Demetrios.
Cheers,
Martin
________________________________________
Von: CHRISTOPHER GERRY [
Betreff: Re: More on the |0>|0> term
I probably shouldn't jump in on this again, but...
I can assure you that there's no thorn in the side of the quantum
optics community concerning the scheme of Kalamidas. There are only
people doing bad calculations. Despite claims to the contrary, our
paper, as with Ghirardi's, does specifically deal with the Kalamidas
proposal. It is quite clearly the case that EXACT calculations in
the Kalamidas proposal shows that the claimed effect disappears. To
suggest that it's there in the approximate result obtained by series
expansion, and therefore must be a real effect, is simply
preposterous. All it means is that the approximation is wrong; in
this case being due to the dropping important terms.
The whole business about the |00> and whatever (the beam splitter
transformations and all that) is not the issue. I'm astonished at
how the debate on this continues. The real problem, and I cannot
emphasize it enough, is this: Kalamidas cannot do quantum optical
calculations, even simple ones and therefore nothing he does should
be taken seriously. As I've said before, his calculation of our Eq.
(9), which I have attached here, is embarrassingly wrong. It's
obvious from the expression of the expectation value in the upper
left that there has to be two terms in the result both containing
the product of r and t. But Kalamidas throws away one of the terms
which is of the same order of magnitude as the one he retains. Or
maybe he thinks that term is zero via the quantum mechanical
calculation of its expectation value, which it most certainly is
not. His limits have been taken inconsistently. So, he not only
does not know how to do the quantum mechanical calculations, he
doesn't even know how or when the limits should be taken. There's
absolutely no point in debating the meaning of the results incorrect
calculations. Of course, by incorrectly doing these things he gets
the result he wants, and then thinks it's the duty of those of us
who can do these calculations to spend time showing him why his
calculations are wrong, which he then dismisses anyway.
My point in again bringing this specific calculation of his is not
to say anything about his proposal per se, but to demonstrate the
abject incompetence of Kalamidas in trying to do even the most
elementary calculations. And if anyone still wonders why I'm angry
about the whole affair, well, what should I feel if some guy unable
to do simple calculations tries to tell established quantum optics
researchers, like me and Mark Hillery, that our paper showing where
he's wrong dismisses ours as being "irrelevant?" He doesn't even
seem to know that what he said was an insult.
And finally, the continued claim that the specific proposal of
Kalamidas has not been addressed must simply stop. It has been
repeatedly. I suspect this claim is being made because people don't
like the results of the correct calculations. That's not the problem
of those of us can carry through quantum optical calculations.
CG
Christopher C. Gerry
Professor of Physics
Lehman College
The City University of New York
718-960-8444
---- Original message ----
Date: Tue, 11 Jun 2013 14:12:19 -0700
From: nick herbert <
Subject: Re: More on the |0>|0> term
To: "Demetrios Kalamidas" <
yer right, demetrios--
the |00> term on the right is always accompanied in Suda's
calculation by a real photon on the left.
But this is entirely non-physical.
No real or virtual quantum event corresponds to this term.
Especially with the high amplitude required for
Suda-interference-destruction.
So your specific approximate FTL scheme despite many general
refutations still remains a puzzlement.
A thorn in the side
of the quantum optics community.
if any think otherwise
let them put on the table
one unambiguous refutation
OF YOUR SPECIFIC PROPOSAL--
not of their own
nor of somebody else's
totally different FTL signaling scheme,
Nick
On Jun 11, 2013, at 1:27 PM, Demetrios Kalamidas wrote:
Nick,
The EP and CSs do derive from the same laser pulse: part of the
pulse pumps the nonlinear crystal and the other part is split off
accordingly to create the CSs.
However, you are still misssing the point: If no EP pair is
created, then you will certainly get '00' on the right
sometimes.... BUT there will be no left photon in existence. The
problem with the Suda term is that when it appears, it appears
only accompanied by a left photon in a superposition state: ie it
always appears as (10+e01)(00+11).
Think of it this way: Suppose you just have an EP source that
creates pairs, with one photon going left and the other right.
Imagine that on the right there is a highly trasnparent BS with
say
|r|^2=0.001. That means that only one out of every thousand right
photons from the EP are reflected, and 999 are transmitted. So,
this means that for every 1000 counts ON THE LEFT, there will be
999 counts tranmitted on the right. Now introduce, at the other
input of that same BS, a CS so that it has a tiny reflected
portion of amplitude |ralpha>. Allegedly then, there will arise
cases where no photon is found in the transmitted channel with
probability equal to |ralpha|^2. Since alpha is arbitrary, we can
choose |
ralpha|=0.1. This means that the probabilty of getting no
photon in
the transmitted channel will be |ralpha|^2=0.01.....Which now
means that, for every 1000 EP pairs created, we will get 1000
counts on the left, but only 900 counts in the transmitted channel
on the right! Whereas, without the CS in the other channel, there
would be
999 counts on the right for that same 1000 counts on the left.
Demetrios
On Tue, 11 Jun 2013 09:44:42 -0700
nick herbert <
Demetrios--
I don't know how the entangled pair (EP) and CSs are generated.
I supposed all three are created with a single PULSE in a non-
linear crystal.
Now one can imagine that this pulse fails to create an EP but
does create a CS
Then some of Bob's detectors will fire but no ES is formed.
So this kind of process could lead to lots of |0>|0> terms.
However what we need are not "lots of |0>|0> terms" but a precise
amplitude (rA) of |0>|0> term.
Given our freedom (in the thought experiment world) to
arbitrarily select
the efficiency of the non-linear crystal, it is hard to see why
the elusive |0>|0>
term would have exactly the right magnitude and phase to cancel
out the interference.
Your original FTL scheme still continues to puzzle me.
Nick
On Jun 11, 2013, at 6:54 AM, Demetrios Kalamidas wrote:
Nick,
The 'entire experimental arrangement' is indeed where the
problem (mystery) arises:
When both CSs are generated it is easy to understand that '00'
will arise, simply because each CS has a non-zero vacuum term.
However, the entire arrangement means inclusion of the
entangled photon pair:
Any time that pair is generated, you are guaranteed to get a
photon on the right, regardless of whether the CSs are there.
So, when entangled pair and CSs are present, there must be at
least one photon at the right. In fact, when only one photon
emerges at the right WE KNOW both CSs were empty.
On Mon, 10 Jun 2013 10:34:30 -0700
nick herbert <
Demetrios--
Sarfatti sent around a nice review of quantum optics
by Ulf Leonhardt that discusses the structure of path-uncertain
photons.
Here is an excerpt:
The interference experiments with single photons mentioned in
Sec. 4.3 have been
performed with photon pairs generated in spontaneous
parametric downconversion
[127]. Here the quantum state (6.28) of light is essentially
|01> |02> + ζ |11>|12 >. (6.29)
In such experiments only those experimental runs count where
photons are counted,
the time when the detectors are not firing is ignored, which
reduces the quantum
state to the photon pair
|11> |12> .
Postselection disentangles the two-mode squeezed
vacuum.
We argued in Sec. 4.3 that the interference of the photon pair
|11> |12> at a 50:50 beam splitter generates the entangled
state (4.24). Without postselection,
however, this state is the disentangled product of two single-
mode squeezed vacua,
as we see from the factorization (6.6) of the S matrix. The
notion of entanglement
is to some extent relative.
this excerpt suggests a possible origin for Suda's |0>|0> term.
In the above process, it's just
the inefficiency of the down converter that generates a |0>|0>
term. That won't do the trick.
But in your more complicated situation--containing two properly
timed coherent states--
when Bohr's "entire experimental arrangement" is considered,
the
| 0>| 0> term may
arise naturally with the proper amplitude and phase. It would
correspond to events when
the coherent states were successfully generated but there were
no events in either upper or lower path.
If this conjecture can be shown to hold true, then the
original Kalamidas proposal would
be refuted by Suda's calculation.
The trick would be to examine--in a thought experiment way--
exactly how those two |A> beams
are created--looking for entanglement with |0>|0> states in
the part of the experiment considered in your proposal.
Nick
ref: Ulf Leonhardt's wonderful review of quantum optics,
starting with reflections from a window pane and concluding
with
Hawking radiation.
Kalamidas entanglement signal scheme decisively disproved - but others not.
- Details
- Category: Jack Sarfatti Blog
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