Traversable ER = EPR wormholes are possible

In 2013 Juan Maldacena and Leonard Susskind demonstrated that the Einstein Rosen bridge between two black holes is created by EPR-like correlations between the microstates of the two black holes. They called this the ER = EPR relation, a geometry–entanglement relationship: entangled particles are connected by a Schwarzschild wormhole. In other words, the ER bridge is a special kind of EPR correlation. Maldacena and Susskind’s conjecture was that these two concepts, ER and EPR, are related by more than a common publication date 1935. If any two particles are connected by entanglement, the physicists suggested, then they are effectively joined by a wormhole. And vice versa: the connection that physicists call a wormhole is equivalent to entanglement. They are different ways of describing the same underlying reality.
Maldacena and Susskind explain that one cannot use EPR correlations to send information faster than the speed of light. Similarly, Einstein Rosen bridges do not allow us to send a signal from one asymptotic region to the other, at least when suitable positive energy conditions are obeyed. This is sometimes stated as saying that (Schwarzschild) Lorentzian wormholes are not traversable.
In 2017, however, Ping Gao, Daniel Louis Jafferis, and Aron C. Wall showed that the ER = EPR allows the Einstein-Rosen bridge to be traversable. This finding comes with implications for the black hole information paradox (of Stephen Hawking) and black hole interiors because hypothetically, an observer can enter a Schwarzschild black hole and then escape to tell about what they have seen. This suggests that black hole interiors really exist and that what goes in must come out and we can learn about the information that falls inside black holes.
Consider a light signal, traveling through the throat of the wormhole. In 1962, Robert Fuller and John Archibald Wheeler were troubled by the apparent possibility that a test particle, or a photon, could pass from one point in space to another point in space, distanced perhaps extremely far away, in a negligible interval of time. Such rapid communication of a particle or a photon, passing through an Einstein-Rosen bridge violates elementary principles of relativity and causality, according to which a light signal cannot exceed the speed of light.
Wheeler and Fuller, however, showed that relativity and causality, despite first expectations, are not violated. It is perfectly possible to write down a mathematical expression for the metric of a space-time which has simple Schwarzschild wormhole geometry. However, when we deal with the passage of light by the “long way” from one wormhole mouth to the other, both on the same space, the throat becomes dynamically unstable and the Einstein-Rosen bridge is non-traversable (see figure, middle).

Wormhole
What would cause an Einstein-Rosen bridge to be traversable? Recall that according to the ER = EPR, an Einstein Rosen bridge between two black holes is created by EPR-like correlations between the microstates of the two black holes. In 2017 scholars found that if one extends the ER = EPR conjecture by equating, not a Schwarzschild wormhole between two black holes and a pair of entangled particles, but a Schwarzschild wormhole and a situation which is somewhat analogous to what occurs in quantum teleportation (between the two sides of the wormhole), then the Einstein-Rosen bridge becomes traversable.
Entanglement alone cannot be used to transmit information and we need quantum teleportation because the qubit is actually transmitted through the wormhole say Gao, Jafferis and Wall: “Suppose Alice and Bob share a maximally entangled pair of qubits, A and B. Alice can then transmit [teleport] the qubit Q to Bob by sending only the classical output of a measurement on the Q-A system. Depending on which of the 4 possible results are obtained, Bob will perform a given unitary operation on the qubit B, which is guaranteed to turn it into the state Q”. But: “Of course in the limit that Alice’s measurement is essentially instantaneous and classical, the traversable window will be very small … — just enough to let the single qubit Q pass through. Therefore, we propose that the gravitational dual description of quantum teleportation understood as a dynamical process is that the qubit passes through the ER=EPR wormhole of the entangled pair, A and B, which has been rendered traversable by the required interaction”.
Next, say Alice throws qubit Q into black hole A. She then measures a particle of its Hawking radiation, a, and transmits the result of the measurement through the external universe to Bob, who can use this knowledge to operate on b, a Hawking particle coming out of black hole B. Bob’s operation reconstructs Q, which appears to pop out of B, a perfect match for the particle that fell into A. The new traversable ER = EPR wormhole allows information to be recovered from black holes. Thus, Gao, Jafferis and Wall write regarding the black hole information paradox:
“Another possible interpretation of our result is to relate it to the recovery of information … [from evaporating black holes]. Assuming that black hole evaporation is unitary, it is in principle possible to eventually recover a qubit which falls into a black hole, from a quantum computation acting on the Hawking radiation. Assuming that you have access to an auxiliary system maximally entangled with the black hole, and that the black hole is an efficient scrambler of information, it turns out that you only need a small (order unity) additional quantity of Hawking radiation to reconstruct the qubit. In our system, the qubit may be identified with the system that falls into the black hole from the left and gets scrambled, the auxiliary entangled system is … on the right, and the boundary interaction somehow triggers the appropriate quantum computation to make the qubit reappear again, after a time of order the scrambling time”. …
Thus, the Gao, Jafferis, Wall ER = EPR wormhole idea seems to extend to the so-called real world as long as two black holes are causally connected and coupled in the right way. If you allow the Hawking radiation from one of the black holes to fall into the other, the two black holes become entangled, and the quantum information that falls into one can exit the other. Thus, Gao, Jafferis and Wall conclude:
“Our example thus provides a way to operationally verify a salient feature of ER=EPR that observers from opposite sides of an entangled pair of systems may meet in the connected interior. … What we found is that if, after the observers jump into their respective black holes, a … coupling is activated, then the Einstein-Rosen [bridge] can be rendered traversable, and the meeting inside may be seen from the boundary. This seems to suggest that the ER=EPR wormhole connection was physically ‘real'”.
Finally the ER = EPR wormhole does not require energy-matter that violates the average null energy condition; the negative energy matter in the ER = EPR configuration is similar to the Casimir effect, and any infinite null geodesic which makes it through the ER = EPR wormhole must be chronal, i.e. the ER = EPR wormhole does not violate Hawking’s chronology protection conjecture. In addition, the ER = EPR wormhole does not violate the generalized second law of thermodynamics.
Therefore, the ER = EPR wormhole is not a configuration with closed time-like curves and it, therefore, does not permit one to travel faster than light over long distances through space; in other words, it cannot serve as a time machine and thus does not violate causality.

 

For further details:

Ping Gao, Daniel Louis Jafferis, Aron C. Wall (2017). Traversable Wormholes via a Double Trace Deformation.

Natalie Wolchover, Newfound Wormhole Allows Information to Escape Black Holes

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The Road to Relativity and Dishonesty in Scientific Research

Prof. Hanoch Gutfreund, the former president of the Hebrew University of Jerusalem, has been plagiarizing my papers and book. To call prof. Gutfreund prolific in plagiarizing my work would be an understatement. The serious damages I sustain from this in Israel are enormous, actually it is far more damaging than I previously thought. I wrote to the president of the Hebrew University in Jerusalem but the latter has not even answered my email. Hence it seems he fails to take responsibility for damage caused by plagiarism. I am not surprised.

In the book, The Road to Relativity: The History and Meaning of Einstein’s “The Foundation of General Relativity” (an annotated facsimile of Einstein’s original handwritten manuscript on general relativity and explanation of Einstein’s manuscript and equations), co-authored by prof. Jürgen Renn, prof. Gutfreund writes:

cosmo

Prof. Gutfreund has picked this passage with only slight changes from my 2013 paper: “George Gamow and Albert Einstein: Did Einstein say the cosmological constant was the “biggest blunder” he ever made in his life?”, ArXiv: 1310.1033v [physics.histph], 03 Oct, 2013.

My name is not mentioned in note 4:

notes

Compare the above paragraph from prof. Gutfreund’s book, The Road to Relativity: The History and Meaning of Einstein’s “The Foundation of General Relativity, to the abstract of my paper, “George Gamow and Albert Einstein: Did Einstein say the cosmological constant was the ‘biggest blunder’ he ever made in his life”:

gamow2

gamow

And compare the penultimate paragraph from prof. Gutfreund’s book, The Road to Relativity: The History and Meaning of Einstein’s “The Foundation of General Relativity to two paragraphs from my paper, “George Gamow and Albert Einstein: Did Einstein say the cosmological constant was the ‘biggest blunder’ he ever made in his life?”:

blunder1

blunder2

In 2016 I received this message from ResearchGate:

gate

My paper gained traffic but no citations, but prof. Gutfreund, who plagiarized my paper, received the citations.

Allen I. Janis writes in his review: “The Road to Relativity: The History and Meaning of Einstein’s ‘The Foundation of General Relativity’.” American Journal of Physics 84, 2016: “An interesting sideline in this chapter has to do with the frequently heard story that Einstein called his introduction of the cosmological constant the biggest mistake of his life. It seems there is no evidence that Einstein ever said or wrote this, and that it is in fact an invention of George Gamow”.

Gamow

It is quite obvious the Prof. Gutfreund has effectively paraphrased the passage from my paper. On November 30, 2015,  Prof. Gutfreund said in his plenary lecture, “100 years of General Relativity – What are we Celebrating?” At the Berlin Conference: A Century of General Relativity:

“But you know there is this Myth that Einstein when he abandoned the cosmological constant he said this is the worst error that I made. There is no evidence for that. Probably he never said that”.

My second bookGeneral Relativity Conflict and Rivalries. Einstein’s Polemics with Physicists (published on December 1, 2015) has a whole chapter dedicated to Einstein’s “biggest blunder”. This chapter is based on my 2013 ArXiv paper: “George Gamow and Albert Einstein: Did Einstein say the cosmological constant was the ‘biggest blunder’ he ever made in his life?”:

gut3

Hence, plagiarism of my 2013 paper on Albert Einstein and George Gamow causes damage to my second book and to my academic status.

In addition, Prof. Gutfreund writes in The Road to Relativity: The History and Meaning of Einstein’s “The Foundation of General Relativity”:

gut

A circle around the origin of coordinates is a rotating disk (in his 1916 paper “The Foundation of General Relativity”, Einstein calls the disk “a circle around the origin”).

In the preceding passage prof. Gutfreund have paraphrased a passage from my 2012 paper, “From the Berlin ‘Entwurf’ Field equations to the Einstein Tensor III: March 1916”, ArXiv: 1201.5358v1 [physics.hist-ph], 25 January, 2012:

disk1

 

disk2

and from my 2014 paper, “Einstein, Schwarzschild, the Perihelion Motion of Mercury and the Rotating Disk Story”, ArXiv, 1411.7370v [physics.hist-ph], 26 Nov, 2014 [Equation (70) is my equation (6) and equation (71) is my equation (11)]:

gut2

Towards the end of his 1916 paper, “The Foundation of General Relativity”, Einstein demonstrates that the gravitational field changes spatial dimensions and the clock period. However, nowhere does Einstein directly relate the rotating disk story to the  above derivation. I have invoked this interpretation of Einstein’s paper. Einstein writes:

Ein5 Ein4

Digital Einstein

On November 30, 2015, Prof. Gutfreund lifted another passage from my paper, “Einstein, Schwarzschild, the Perihelion Motion of Mercury and the Rotating Disk Story” and changed a word here and there, in his plenary lecture, “100 years of General Relativity – What are we Celebrating? at the Berlin Conference: A Century of General Relativity:

“Another thing which he could have done. So he already knew the Schwarzschild solution, because the Schwarzschild correspondence is in December. He wrote this paper [review paper, 1916] later. He submitted it only in March. So he could have used this Schwarzschild solution who showed a simpler derivation of the motion of the perihelion and of the bending of light and he did not do it”.

In the abstract of my paper, “Einstein, Schwarzschild, the Perihelion Motion of Mercury and the Rotating Disk Story”, ArXiv, 1411.7370v [physics.hist-ph], 26 Nov, 2014, I wrote:

“On November 18, 1915 Einstein reported to the Prussian Academy that the perihelion motion of Mercury is explained by his new General Theory of Relativity: Einstein found approximate solutions to his November 11, 1915 field equations. Einstein’s field equations cannot be solved in the general case, but can be solved in particular situations. The first to offer such an exact solution was Karl Schwarzschild. Schwarzschild found one line element, which satisfied the conditions imposed by Einstein on the gravitational field of the sun, as well as Einstein’s field equations from the November 18, 1915 paper. On December 22, 1915 Schwarzschild told Einstein that he reworked the calculation in his November 18 1915 paper of the Mercury perihelion. Subsequently Schwarzschild sent Einstein a manuscript, in which he derived his exact solution of Einstein’s field equations. On January 13, 1916, Einstein delivered Schwarzschild’s paper before the Prussian Academy, and a month later the paper was published. In March 1916 Einstein submitted to the Annalen der Physik a review article on the general theory of relativity. The paper was published two months later, in May 1916. The 1916 review article was written after Schwarzschild had found the complete exact solution to Einstein’s November 18, 1915 field equations. Einstein preferred in his 1916 paper to write his November 18, 1915 approximate solution upon Schwarzschild exact solution (and coordinate singularity therein).”

He could have though picked the idea from my 2012 paper, Weinstein, Galina, “From the Berlin ‘Entwurf’ Field equations to the Einstein Tensor III: March 1916”, ArXiv: 1201.5358v1 [physics.hist-ph], 25 January, 2012:

Scwarzschild.jpg

Einstein’s equations in his 1916 paper, “The Foundation of General Relativity”:

Schwartz1

Schwartz2

Schwartz3

In my book, General Relativity Conflict and Rivalries. Einstein’s Polemics with Physicists  I have also developed my previous ideas from my paper, “Einstein, Schwarzschild, the Perihelion Motion of Mercury and the Rotating Disk Story”.