REVIEW 6 cited by
Quantum Rods and Clock in a Gravitational Universe
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
read the original abstract
Local operators are the basic observables in quantum field theory which encode the physics observed by a local experimentalist. However, when gravity is dynamical, diffeomorphism symmetries are gauged which apparently obstructs a sensible definition of local operators, as different locations in spacetime are connected by these gauged symmetries. This consideration brings in the puzzle of reconciling our empirical world with quantum gravity. Intuitively, this puzzle can be avoided using relatively defined observables when there exists a natural reference system such as a distribution of galaxies in our universe. Nevertheless, this intuition is classical as the rods and clock defined in this way may also have quantum fluctuations so it is not a priori clear if it can be realized in the quantum regime. In this letter, we provide an affirmative answer to this question. Interestingly, we notice that the quantum fluctuations of the reference system are in fact essential for the realization of the above intuition in the quantum regime.
Forward citations
Cited by 6 Pith papers
-
Observers, local measurements, and topology
Measurement correlations along an observer's worldline define a simplicial complex whose homology is proposed to be the topology of the accessible quantum-gravitational spacetime.
-
Entanglement Entropy of Quantum Corners
For a two-dimensional corner symmetry algebra, coherent corner states give an entanglement entropy that scales with the area when mapped to near-extremal Reissner-Nordström black holes.
-
Cosmological correlators in gravitationally-constrained de Sitter states
Cosmological correlators in gravitationally constrained de Sitter states are conformally invariant and differ from QFT vacuum correlators, but relational observables with a heavy background state can reproduce QFT results.
-
Algebras, Entanglement Islands, and Observers
Entanglement islands in the AdS/bath island model realize the quantum-gravity 'observer' as a Goldstone vector mode, making the island operator algebra an emergent Type II∞ von Neumann algebra.
-
An apologia for islands
Entanglement islands and Page curves can arise in massless gravity without an external bath, and compactly supported gauge-invariant operators exist in islands around generic symmetry-breaking black hole backgrounds.
-
The Mechanism behind the Information Encoding for Islands
Island information is encoded in the bath because island operators are gravitationally dressed to the bath via the massive-graviton Stückelberg field, realized as Wilson lines in the Karch-Randall braneworld.
Discussion (0). Continue with ORCID to comment.