Text Size


Goodbye to linear unitary S-Matrix conservation of information in the black hole firewall debate.

On Jul 7, 2014, at 2:24 PM, art wagner <wagnerart@hotmail.com> wrote:

Now, combine that with this ....

The ability of the Bohmian formalism to analyze this last type of problems

for (open) quantum systems remains mainly unexplored by the scientific community. The authors of this

review are convinced that the nal status of the Bohmian theory among the scientific community will

be greatly infuenced by its potential success in these type of problems that present non-unitary and/or

nonlinear quantum evolutions.



Abstract. Bohmian mechanics provides an explanation of quantum phenomena in terms of point particles
guided by wave functions. This review focuses on the formalism of non-relativistic Bohmian mechanics,
rather than its interpretation. Although the Bohmian and standard quantum theories have different
formalisms, both give exactly the same predictions for all phenomena. Fifteen years ago, the quantum
chemistry community began to study the practical usefulness of Bohmian mechanics. Since then, the scientific 
community has mainly applied it to study the (unitary) evolution of single-particle wave functions,
either by developing efficient quantum trajectory algorithms or by providing a trajectory-based explanation
of complicated quantum phenomena. Here we present a large list of examples showing how the Bohmian
formalism provides a useful solution in different forefront research elds for this kind of problems (where
the Bohmian and the quantum hydrodynamic formalisms coincide). In addition, this work also emphasizes
that the Bohmian formalism can be a useful tool in other types of (non-unitary and nonlinear) quantum
problems where the influence of the environment or the global wave function are unknown. This review
contains also examples on the use of the Bohmian formalism for the many-body problem, decoherence
and measurement processes. The ability of the Bohmian formalism to analyze this last type of problems
for (open) quantum systems remains mainly unexplored by the scientific community. The authors of this
review are convinced that the final status of the Bohmian theory among the scientic community will
be greatly influenced by its potential success in these type of problems that present non-unitary and/or
nonlinear quantum evolutions. A brief introduction of the Bohmian formalism and some of its extensions
are presented in the last part of this review.

Are entangled particles connected by wormholes? Support for the ER=EPR conjecture from entropy inequalities

If spacetime is built out of quantum bits, does the shape of space depend on how the bits are entangled? The ER=EPR conjecture relates the entanglement entropy of a collection of black holes to the cross sectional area of Einstein-Rosen (ER) bridges (or wormholes) connecting them. We show that the geometrical entropy of classical ER bridges satisfies the subadditivity, triangle, strong subadditivity, and CLW inequalities. These are nontrivial properties of entanglement entropy, so this is evidence for ER=EPR. We further show that the entanglement entropy associated to classical ER bridges has nonpositive interaction information. This is not a property of entanglement entropy, in general. For example, the entangled four qubit pure state |GHZ_4>=(|0000>+|1111>)/sqrt{2} has positive interaction information, so this state cannot be described by a classical ER bridge. Large black holes with massive amounts of entanglement between them can fail to have a classical ER bridge if they are built out of |GHZ_4> states. States with nonpositive interaction information are called monogamous. We conclude that classical ER bridges require monogamous EPR correlations.
On Jul 7, 2014, at 2:11 PM, JACK SARFATTI <adastra1@me.com> wrote:

Yes, this is consistent with what I told Addinal today about Tegmark multiverse Levels 1, 2 & 3
3 is pilot “mind" field for “material" 1 & 2 that must be linked with wormholes as in ER = EPR, but they must not pinch off for consistent
CTC  time travel to past histories.
Those wormholes that do pinch off are perhaps the “discontinuities” that Fred Wolf mentioned. 

"It was shown recently that replacing classical geodesics with quantal (Bohmian) trajectories gives
rise to a quantum corrected Raychaudhuri equation (QRE). Here we derive the second order Friedmann
equations from the QRE, and show that this also contains a couple of quantum correction
terms, the first of which can be interpreted as cosmological constant (and gives a correct estimate
of its observed value), or as dark matter, while the second as a radiation term in the early universe,
which gets rid of the big-bang singularity and predicts an infinite age of our universe."

On Jul 7, 2014, at 2:01 PM, art wagner <wagnerart@hotmail.com> wrote:

On Jul 6, 2014, at 11:20 PM, fred alan wolf <fawolf@ix.netcom.com> wrote:

          Actually there may be inconsistencies in the Deutsch model.  See attached paper.  I visited with these physicists who discovered them (Tom Imbo is the head physicist for the group) at UIC when I was in Chicago last May.  The bottom line is that there are CTCs that are discontinuous.  I quote their paper’s conclusion (in black with a different font):
We have considered Deutsch's model of a non-time traveling system interacting with a time traveler confined to a bounded region, and have demonstrated that the state of the non-time traveler in the asymptotic future can be a discontinuous function of the state in the asymptotic past. Furthermore, we have demonstrated that these discontinuities occur independent of the method of choosing a unique consistent time traveling state, as well as independent of whether Deutsch's assumption regarding the initial composite state or Politzer's generalization is used. Given the phenomenon of discontinuous evolutions within the Deutsch model, we note several possible reactions.
(1) Question the assumptions upon which Deutsch's model is based. However, relaxing the two most obvious
of these, as stated in the previous paragraph, does not provide any respite. Thus, the only remaining natural
assumptions to be questioned are that (a) the spatial degrees of freedom can be treated classically, (b) the effect of the systems on the surrounding spacetime can be neglected, and finally that (c) a quantum mechanical (as opposed to field-theoretic) model captures the relevant dynamics. Although over-idealizations can indeed lead to apparent discontinuities, none of (a)-(c) above seems obviously responsible for the discontinuous behavior in Deutsch's model. In particular, it is difficult to believe that there is no imaginable configuration utilizing a discontinuous gate for which these approximations are sufficiently justified.
(2) Accept the assumptions of the Deutsch model, but further assume that nature either does not utilize those
gates which are physically discontinuous, or does not allow initial states of the non-time traveler which are near a discontinuity. (Analogous tactics have been considered in the classical case as a way of avoiding the grandfather paradox .) However, this solution is somewhat ad hoc and inelegant. In addition, placing such restrictions on initial states and/or gates sacrifices one of the great strengths of Deutsch's approach which purports to provide a viable model for any set of initial conditions and any dynamics.
(3) Accept that the Deutsch model is correct as writ, but interpret the existence of discontinuous evolutions as
evidence that CTC's are unphysical.
(4) Acknowledge that quantum mechanics in the presence of CTC's is sufficiently strange that the existence of these discontinuities is a fitting physical consequence. Further study will be required not only to adequately
address these reactions, but also to answer other interesting questions raised by our results, such as: What are the exact properties of the gates which give rise to such peculiar evolutions? For any such gate, how are the points at which the evolution is discontinuous distributed in the space of initial states? Do these discontinuities occur in other approaches to quantum systems in the presence of CTC's? Regardless, it is clear that discontinuous evolutions are an unavoidable feature of the Deutsch model, and are yet another strange and fascinating consequence of the attempt to bring together quantum mechanics and gravity.
            Generally speaking discontinuities indicate that we may be lacking a required extension of the model.  My PhD thesis was about discontinuities appearing in large amplitude (nonlinear) plasma waves wherein such discontinuities vanished when appropriate care was taken to add charge separation between ions and electrons in the plasma (which had previously been neglected in such studies, hence my thesis) when such waves pass through the plasma. 
            Perhaps we are missing some physics here in the nonlinear Deutsch CTCs as was the case in the nonlinear plasma wave model I looked at a long time ago.
            Such discontinuous behavior is absent from the Lloyd CTC model and I would be surprised if any cropped up, since it is based on linear quantum physics.  Remember the Deutsch model is inherently nonlinear and a new idea (nonlinearity) being added to quantum physics, so we might expect discontinuous behavior to crop up, whereas the Lloyd model is not—it is based on linear quantum physics.
Best Wishes,
Fred Alan Wolf Ph.D.  aka Dr. Quantum ®
Have Brains / Will Travel
San Francisco
web page: 
Blog page: 

From: JACK SARFATTI [mailto:jacksarfatti@gmail.com] 
Sent: Sunday, July 06, 2014 6:34 PM
To: Robert Addinall

Fred Wolf has been working on that difference
On Jul 6, 2014, at 5:45 PM, Robert Addinall <beowulfr@interlog.com> wrote:

Seth Lloyd’s talk at the Perimeter Institute was good, and it appears that the Deutsch and P-CTCs models are incompatible.
However, I wonder if it is possible that both could happen – there are consistent CTCs (maybe a lot of them, as in your theory of consciousness), but there are also some inconsistent ones that can bump a time traveler across to a parallel universe.  Do you have any thoughts on that?
there are never any inconsistent CTCs not even in Deutsch’s theory - jumping to the universe next door is a consistent narrative.
John Gribbin has the best pop explanation of Deutsch’s theory in his new quantum computer book.

From: JACK SARFATTI [mailto:jacksarfatti@gmail.com] 
Sent: July-05-14 2:09 PM
Subject: Re: H. Wiseman-- "Bell's Theorem Still reverberates" & Hauke Traulsen's entanglement swapping "FLASH"
Thanks Nick
Of course your proof is expected because Traulsen only uses linear unitary orthodox quantum theory. Antony Valentini’s post-quantum theory, in contrast, is a totally new physics of a nonlinear non-unitary post-quantum theory.
However, Nick it is not yet clear to me that your density matrix computation applies to Traulsen’s use of the HOM Effect below?

Subquantum Information and Computation

(Submitted on 11 Mar 2002 (v1), last revised 12 Apr 2002 (this version, v2))
It is argued that immense physical resources - for nonlocal communication, espionage, and exponentially-fast computation - are hidden from us by quantum noise, and that this noise is not fundamental but merely a property of an equilibrium state in which the universe happens to be at the present time. It is suggested that 'non-quantum' or nonequilibrium matter might exist today in the form of relic particles from the early universe. We describe how such matter could be detected and put to practical use. Nonequilibrium matter could be used to send instantaneous signals, to violate the uncertainty principle, to distinguish non-orthogonal quantum states without disturbing them, to eavesdrop on quantum key distribution, and to outpace quantum computation (solving NP-complete problems in polynomial time).
Also Seth Lloyd’s schemes on post-selection simulations of QM computing on CTCs, which should not be same as linear unitary orthodox QM if it is really a faithful simulation.

Search Results

1.   Time travel theory avoids grandfather paradox - Phys.org

 Rating: 4.2 - ‎58 votes
Jul 21, 2010 - The model of time travel proposed by Seth Lloyd, et al., in a recent paper at arXiv. org arises from their investigation of the quantum mechanics ...

2.   The quantum mechanics of time travel through post-selected ...

by S Lloyd - ‎2010 - ‎Cited by 32 - ‎Related articles
Jul 15, 2010 - We analyze a specific proposal for such quantum time travel, the quantum ... Seth Lloyd, Lorenzo Maccone, Raul Garcia-Patron, Vittorio ...

3.   Quantum Time Machine Solves Grandfather Paradox | MIT ...

MIT Technology Review
Jul 19, 2010 - A new kind of time travel based on quantum teleportation gets around ... forward by Seth Lloyd at the Massachusetts Institute of Technology and ...

4.   Should Time Travel Be A Moral Imperative? - Forbes

by Bruce Dorminey - Aug 28, 2013 - That's the question I posed to MIT quantum mechanic Seth Lloyd, who ... If time travel is possible, should society be ethically obligated to try and ...

5.   The Quantum Mechanics of Time Travel - YouTube

Dec 16, 2010 - Uploaded by QuantumIQC
Dr. Seth Lloyd, an MIT professor and self-described "quantum mechanic," describes the quantum ...

6.   Quantum mechanics of time travel - Wikipedia, the free ...

Jump to Lloyd's prescription - [edit]. An alternative proposal was later presented by Seth Lloyd based upon post -selection and path integrals.
You've visited this page 2 times. Last visit: 1/19/14

7.   Grandfather paradox - Wikipedia, the free encyclopedia

The grandfather paradox is a proposed paradox of time travel first described by the ...Seth Lloyd and other researchers at MIT have proposed an expanded ...

8.   NOVA | A Quantum Leap in Computing - PBS

Public Broadcasting Service
Jul 21, 2011 - MIT's Seth Lloyd, a pioneer of quantum computing, explains its ... you can think of time travel, the process of going from the future into the past, ...

9.   Quantum time machine 'allows paradox-free time travel ...

The Daily Telegraph
by Tom Chivers - Jul 22, 2010 - Scientists have for some years been able to 'teleport' quantum states from one place to another. Now Seth Lloyd and his MIT team say that, ...
On Jul 5, 2014, at 9:26 AM, nick herbert <quanta@cruzio.com> wrote:

Saul-Paul --
"Bell's Theorem still reverberates." What a great word "reverberate"!
Thanks for the update on BT.
Did a bit more work on Traulsen's PSBA proposal by calculating the Density Matrix BS for a random mix of the 4 Bell States, compared to the Density Matrix PS for a random mix of the 4 uncorrelated polarization states |H>|H>, |H>|V>, |V>|H> and |V>|V>.
The result (not surprising) is that PS = BS. The density matrix for both of these situations is the same.
Thus quantum mechanics predicts that all statistical averages for these two situations will be the same. Hence no FTL signal (on the average).
Hence the only way that Traulsen's PSBA scheme could work is that if individual measurement events give distinguishable results for the BS and PS cases, while the average of these results remains identical.Traulsen has proposed a couple of measurement schemes (Fig 4 on his paper). It would be interesting to calculate the expected outputs of these two measurement schemes to the eight possible inputs (4 BS states and 4 PS states) to see if one can observe patterns in the individual detector responses that might be able to reveal whether a Bell State (BS) was the input, or whether the input was an uncorrelated polarization state (PS).
Nick Herbert
On Jul 4, 2014, at 7:14 PM, Saul-Paul and Mary-Minn Sirag wrote:

The June 26 issue of Nature has a very interesting article by Howard Wiseman: "Bell's theorem still reverberates".  Wiseman emphasizes the fact that Bell's 1976 paper went somewhat beyond the 1964 paper. In this 1976 paper "local causes" are ruled out.
          Wiseman also has a 35 page paper on the Arxiv on this same topic.
He has posted many other Arxiv papers.
All for now;-)
On Jul 4, 2014, at 4:52 PM, nick herbert wrote:

Dear Hauke Traulsen --
One of my hobbies is attempting FTL communication using quantum entanglement. I have found, like you, that almost nobody is interested in these schemes because "everyone knows this is impossible" so one's time is better spent on the "physics of the possible". However, tho I agree in principle with this consensus it seems to me that there are at least three reasons to devise refutations for FTL schemes:

1. to show off what a good physicist you are -- if a scheme is impossible, it should be easy to refute;

2. Constructing a refutation might deepen your own knowledge of, say, the physics of entanglement, and

3. might lead, if not to FTL signaling, possibly to some new result that no one had ever seen before.

I might also add a fourth reason:

4. sheer intellectual curiosity -- a quality in rare supply in these days of "hurry-up" physics.

My FTL efforts started with Alice deciding whether to collapse her A photons in the circularly-polarized basis (R and L photons) or in the plane-polarized basis (H and V photons). Because of entanglement, Bob's photons (previously polarization-undecided) collapse into the same basis. Alice sends a coded  message by switching between CUP (circularly unpolarized light) and PUP (plane-unpolarized light). If Bob can distinguish between a stream of random  R and L photons and a stream of random H and V photons, then he can decode Alice's (FTL) message. Since both CUP light and PUP light (altho seemingly  physically distinct beams of photons) possess exactly the same density matrix, quantum theory predicts that no experiment exists that can distinguish these two (ostensibly different) kinds of light.
[Lots of room for philosophy here: H, V, R and L photons are physically different. Yet a random beam of H and V photons cannot be distinguished from a random beam of R and L photons. No one can really say why.]
I have spent a lot of time devising clever schemes to make the CUP/PUP distinction and have learned a lot of physics. One of my schemes (called FLASH) led directly to the famous quantum no-cloning rule.
But that is all in the past.
The quest for FTL signaling via quantum entanglement has moved beyond these early failures into fresh new ground -- your clever scheme being the newest.
I would characterize second-generation FTL schemes as an attempt to expand the dimensions of Bob's measurement space. In Demetrios Kalamidas's recent FTL device, Bob's photons were coherently mixed with a truncated coherent state which increased the number of Bob's output possibilities. Kalamidas's scheme was recently refuted by a small team of experts.
In my ETCALLHOME proposal I used a scheme similar to yours to permit Bob to look at TWO CONSECUTIVE PHOTONS -- hence to expand Bob's Hilbert space from 2 complex dimensions to 4.
By "similar to yours" I mean a thought experiment in which, in addition to the common SOURCE O producing a pair of entangled photons (sent to A and B) The SOURCE O also sends a TIMING SIGNAL to A and B so that ALICE and BOB can, if they wish, coherently mix two consecutive photons  by knowledgably adjusting optical delay lines. (This is cheap and easy to do with a thought experiment) This timing information (in your case, you envision "storing the photons" -- also easy to do in the mental lab) allows for a more complex measurement on Bob's part which might allow him to perform a more subtle kind of measurement than is encoded into the density matrix.
In my ETCALLHOME experiment, Alice makes no use of her timing signal, she just sends 2-ples of photons, either both CUP or both PUP. Bob using his timing signal combines his two photons coherently in a 50/50 beamsplitter and hopes to see if he can get a different output from combining two CUP photons from combining two PUP photons. A simple calculation (as explained to me by Lev Vaidman) shows that both pairs of photons yield the same result. No FTL signaling is possible using the ETCALLHOME scheme.
With this preface behind me, I would like to consider your PSBA scheme.
Like ETCALL HOME, PSBA uses timing information (or photon storage) to combine two consecutive photons. Only in your case both Alice and Bob use the timing info, potentially leading to greater possibility of consummating a robust FTL connection.
I am only beginning to understand your PSBA scheme. So please correct me if I am wrong.
In your scheme Alice switches from two kinds of measurement on her photon 2-ples. Either she chooses to make a Bell-state measurement (BSM), which ENTANGLES distant Bob's 2-ple. Or she merely detects the two photons (SSM = separable-state measurement) which leaves Bob's 2-ple unentangled.
Using your scheme Alice sends PAIRS OF PHOTONS (2-ples) to Bob that are either mutually ENTANGLED (logical ONE) or mutually UNCORRELATED (logical ZERO). If Bob can discern this difference, either in a single measurement or in a series of measurements on identically prepared pairs, then Bob can decode Alice's FTL signals with the usual apocalyptic consequences -- time machines, causality-violation, grandfather paradoxes, stock-market windfalls and much much more.
Have I got your scheme right? Bob's task is to look at a sequence of PHOTON PAIRS and decide whether they are POLARIZATION-ENTANGLED or POLARIZATION UNCORRELATED.
If I have you scheme right?
(Already you can begin to see the outline of a refutation: there are 4 ways that a pair of photons can be entangled (the four Bell states). A random sequence of these Four Degrees of Entanglement might well be experimentally indistinguishable from a random sequence of uncorrelated pairs.)
Enough for now.
Thanks for your imaginative FTL scheme.
Nick Herbert
On Jul 3, 2014, at 2:47 AM, Hauke Traulsen wrote:

Hi Nick,

thanks for your reply. Actually there has been no response regarding my publication so far. ;). 

Regarding your second email:  If you want to test correlation for every single photon pair you need classical communication, that's obviously right.
My hope is that analyzing a sequence of entangled photons pairs (without additional classical information) one could determine a statical distribution of detected Bell-States,  which is different from 25%-25%-25%-25% for polarization-entangled photons. 

For example: What about the HOM effect at a symmetrical 50:50 beam splitter?

Hong–Ou–Mandel effect

From Wikipedia, the free encyclopedia
The Hong–Ou–Mandel effect is a two-photon interference effect in quantum optics which was demonstrated by three physicists, C. K. Hong, Z. Y. Ou and Leonard Mandel in 1987 from the University of Rochester.[1] The effect occurs when two identical single-photon waves enter a 50:50 beam splitter, one in each input port. When both photons are identical they will extinguish each other. If there are changes in phase, the probability of detection will increase. In this way the interferometer can measure accurately bandwidth, path lengths and timing. http://en.wikipedia.org/wiki/Hong–Ou–Mandel_effect
  1. I expected that for a sequence of entangled photon pairs only pairs in the HV-VH state (antisymmetrical) have the strength to leave the BS though different exits (even under perfect HOM-dip-conditions), which lets one observe and distinguish this state in 25% of all pairs at the BS (by detecting parallel two photons on different outputs of the 50:50 BS).

  1. For a sequence of unentangled photon pairs i expect that the photons of each pair leave the 50:50 BS through the same exit (under perfect HOM-Dip-Conditions 100%) with 50%-50% propability for exit #1 and exit #2.

And for distinguishing 1. and 2. no futher classical communication would be necessary. 

What do you think? Is my assumption regarding the HOM Dip and the HV-VH generally wrong, and if so, why?

Thanks for any hint, best regards,

Am 01.07.2014 21:57, schrieb nick herbert:
Hauke Traulsen--
i am reading with much interest your new FTL signaling scheme, I have somewhat of a history with such schemes
even publishing a book on the subject "Faster Than Light -- Superluminal Loopholes in Physics" New American Library 1988. 
Recently I collaborated in refuting a clever FTL scheme devised by Demetrios Kalamidas. For more information on 
"The Kalamidas Effect" see these two entries on my Quantum Tantra blog.
I am sure that by now you have received many attempts to refute your scheme. But have you yet received one that really does the job? 
I would appreciate hearing from you if your scheme has already been refuted.
in the meantime i am subjecting your paper to careful scrutiny (and am admiring your cleverness) and have forwarded this paper to all members 
of the team that helped to refute the Kalamidas Scheme.
warm regards
Nick Herbert

Unsere aktuellen L.I.N.K.-News finden Sie unter: www.iis.fraunhofer.de/link-newsletter
Hauke Traulsen
Gruppe Technologien
Zentrum für Intelligente Objekte ZIO
Fraunhofer-Arbeitsgruppe für Supply Chain Services SCS
Nordostpark 93  |  90411 Nürnberg, Germany
Telefon +49 911 58061-9548  |  Fax +49 911 58061 9598
www.scs.fraunhofer.de  |  www.zio.fraunhofer.de
<0908.2655v4discontinous Deutsch CTCs.pdf>