Warmhole is the weirdest theoritical physics phenomenon, which links pair of blackhole..
Quantum Gravity in the Lab:
Teleportation by Size and Traversable Wormholes
With the long-term goal of studying quantum gravity in the lab, we propose holographic
teleportation protocols that can be readily executed in table-top experiments. These protocols
exhibit similar behavior to that seen in the recent traversable wormhole constructions of [1, 2]:
information that is scrambled into one half of an entangled system will, following a weak
coupling between the two halves, unscramble into the other half. We introduce the concept
of teleportation by size to capture how the physics of operator-size growth naturally leads to
information transmission. The transmission of a signal through a semi-classical holographic
wormhole corresponds to a rather special property of the operator-size distribution we call size
winding. For more general setups (which may not have a clean emergent geometry), we argue
that imperfect size winding is a generalization of the traversable wormhole phenomenon. For
example, a form of signalling continues to function at high temperature and at large times
for generic chaotic systems, even though it does not correspond to a signal going through a
geometrical wormhole, but rather to an interference effect involving macroscopically different
emergent geometries. Finally, we outline implementations feasible with current technology
in two experimental platforms: Rydberg atom arrays and trapped ions.
INTRODUCTION
In the quest to understand the quantum nature of spacetime and gravity, a key difficulty is the
lack of contact with experiment. Since gravity is so weak, directly probing quantum gravity means
going to experimentally infeasible energy scales. However, a consequence of the holographic
principle [3, 4] and its concrete realization in the AdS/CFT correspondence [5–7] (see also [8]) is
that non-gravitational systems with sufficient entanglement may exhibit phenomena characteristic
of quantum gravity. This suggests that we may be able to use table-top physics experiments to probe
quantum gravity indirectly. Indeed, the technology for the control of complex quantum many-body
systems is advancing rapidly, and we appear to be at the dawn of a new era in physics—the study
of quantum gravity in the lab.
The purpose of this paper is to discuss one way in which quantum gravity can make contact
with experiment. We will focus on a surprising communication phenomenon. We will examine a
particular entangled state—one that could actually be made in an atomic physics lab—and consider
the fate of a message inserted into the system in a certain way. Since the system is chaotic, the
message is soon dissolved amongst the constituent parts of the system. The surprise is what happens
next. After a period in which the message seems thoroughly scrambled with the rest of the state, the
message then abruptly unscrambles, and recoheres at a point far away from where it was originally
inserted. The signal has unexpectedly refocused, without it being at all obvious what it was that
acted as the lens.
One way to describe this phenomenon is just to brute-force use the Schrodinger equation. But
what makes this phenomenon so intriguing is that it has a much simpler explanation, albeit a
simple explanation that arises from an unexpected direction [1]. If we imagine the initial entangled
quantum state consists of two entangled black holes, then there is a natural explanation for why
the message reappears—it travelled through a wormhole connecting the two black holes! This is a
phenomenon that one could prospectively realize in the lab that has as its most compact explanation
a story involving emergent spacetime dimensions.
An analogy may be helpful. Consider two people having a conversation, or as a physicist might
describe it “exchanging information using sound waves”. From the point of view of molecular
dynamics, it is remarkable that they can communicate at all. The room might contain 1027 or more
molecules with a given molecule experiencing a collision every 10−10s or so. In such a system, it is
effectively impossible to follow the complete dynamics: the butterfly effect implies that a computer
would need roughly 1037 additional bits of precision every time it propagated the full state of the
system for one more second. Communication is possible despite the chaos because the system
nevertheless possesses emergent collective modes—sound waves—which behave in an orderly
fashion.
When quantum effects are important, complex patterns of entanglement can give rise to qualita-
tively new kinds of emergent collective phenomena. One extreme example of this kind of emergence
is precisely the holographic generation of spacetime and gravity from entanglement, complexity,
and chaos. In such situations, new physical structures become possible, including wormholes which
connect distant regions of spacetime. And like the physics of sound in the chaotic atmosphere of the
room, the physics of these wormholes points the way to a general class of quantum communication
procedures which would otherwise appear utterly mysterious. The experimental study of such
situations therefore offers a path toward a deeper understanding of quantum gravity. By probing
stringy corrections to the gravitational description, a sophisticated experiment of this type could
even provide an experimental test of string theory.
(source:the arXiv)
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