Pith. sign in

REVIEW 21 cited by

A Covariant Entropy Conjecture

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

arxiv hep-th/9905177 v3 pith:4XMXFKEB submitted 1999-05-24 hep-th astro-phgr-qc

A Covariant Entropy Conjecture

classification hep-th astro-phgr-qc
keywords boundconjectureentropyadmittedareabecausebekensteinblack
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

We conjecture the following entropy bound to be valid in all space-times admitted by Einstein's equation: Let A be the area of any two-dimensional surface. Let L be a hypersurface generated by surface-orthogonal null geodesics with non-positive expansion. Let S be the entropy on L. Then S does not exceed A/4. We present evidence that the bound can be saturated, but not exceeded, in cosmological solutions and in the interior of black holes. For systems with limited self-gravity it reduces to Bekenstein's bound. Because the conjecture is manifestly time reversal invariant, its origin cannot be thermodynamic, but must be statistical. Thus it places a fundamental limit on the number of degrees of freedom in nature.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 21 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Analytic Boundaries of Infinite-Spin-Tower Amplitudes from Hidden Zero

    hep-th 2026-07 conditional novelty 7.0

    The exact analytic boundary of unitary infinite-spin-tower amplitudes is derived and shown to be maximal unless energy poles accumulate.

  2. Covariant unification of holographic c-functions

    hep-th 2026-05 unverdicted novelty 7.0

    A new covariant c-function is defined from extrinsic curvature of codimension-two bulk slices, unifying prior foliation-based definitions and exhibiting expected monotonic behavior in conformal, confining, and mixed-g...

  3. Relative entropy for $\lambda \phi^4$ in the Rindler wedge

    hep-th 2026-07 accept novelty 6.5

    Relative entropy of vacuum vs coherent state for λφ⁴ in the Rindler wedge equals the classical interacting boost charge to O(λ) and obeys the Bekenstein bound.

  4. Holographic timelike complexity for de Sitter

    hep-th 2026-07 conditional novelty 6.0

    Timelike subregion volume complexity in de Sitter grows exponentially early and diverges hyperfast at a maximal duration; near the SdS black hole horizon the divergence is replaced by slower, claimed-nonlinear growth.

  5. Entropy bound and the non-universality of entanglement islands

    hep-th 2026-04 unverdicted novelty 6.0

    Universal compact entanglement islands are obstructed by an entropy bound violation, implying region-dependent interior reconstruction.

  6. Bounding relative entropy for non-unitary excitations in quantum field theory

    math-ph 2026-04 unverdicted novelty 6.0

    Convexity of non-commutative L^p norms yields bounds on relative entropy for arbitrary excitations of faithful states in general von Neumann algebras, with uniform boundedness proven for single-particle states of the ...

  7. Background instability of quintessence model in light of entropy and distance conjecture

    hep-th 2026-01 conditional novelty 6.0

    An entropy comparison shows quintessence backgrounds with a finite event horizon are unstable, equating the trans-Planckian censorship bound with a species-entropy growth condition.

  8. Diamonds in the Bulk and Large-$N$ Scaling in AdS/CFT

    hep-th 2026-01 conditional novelty 6.0

    Bulk field algebras of causal diamonds in AdS/CFT require a double-scaling limit, so sub-AdS-radius distances are not described by bulk QFT.

  9. Dark Matter from Holography

    astro-ph.CO 2025-11 unverdicted novelty 6.0

    Holographic dark matter arises from the Ricci cutoff in a baryon-plus-radiation universe, matching observed densities and reversing the sign of pre-existing negative vacuum energy to match observations.

  10. Curious QNEIs from QNEC: New Bounds on Null Energy in Quantum Field Theory

    hep-th 2025-10 unverdicted novelty 6.0

    Derives new state-independent lower bounds on semi-local integrals of null energy flux in QFTs of two and higher dimensions using QNEC, strong subadditivity, and modular Hamiltonians.

  11. Information Metrics and Possible Limitations of Local Information Objectivity in Quantum Gravity

    gr-qc 2025-01 unverdicted novelty 6.0

    Quantum gravity may permit contextual deviations from the Fisher metric, inducing observer-dependent modifications to the Born rule.

  12. Cosmological horizon thermodynamics in Gauss-Bonnet quasi-dilaton Massive Gravity

    gr-qc 2026-07 reject novelty 5.0

    Gauss-Bonnet quasi-dilaton massive gravity is claimed to obey horizon thermodynamics and the holographic entropy bound, provided the Gauss-Bonnet coupling is non-negative.

  13. Landauer entropy of spacetime

    gr-qc 2026-05 unverdicted novelty 5.0

    A geometrical entropy for static spherically symmetric spacetimes is defined from Landauer's principle applied to geodesic congruences, obeys a second law, and equals Bekenstein-Hawking entropy.

  14. Toward a Phenomenologically Acceptable Quantum Cyclic Universe

    gr-qc 2026-05 unverdicted novelty 4.0

    A finite-dimensional quantum model with commensurable energy eigenvalues and minimum-entropy initial condition yields exact periodicity and a distinguished entropy minimum that may represent the Big Bang while suppres...

  15. Landauer entropy of spacetime

    gr-qc 2026-05 unverdicted novelty 4.0

    Defines Landauer entropy for static spherically symmetric spacetimes as a surface integral over geodesic entropies, establishes a second law under mild assumptions, and relates the result to Bekenstein-Hawking entropy.

  16. Nonperturbative Isentropic Processes in AdS Black Holes with Nonlinear Electrodynamics

    hep-th 2026-01 reject novelty 4.0

    For four nonlinear-electrodynamics AdS black holes, isentropic absorption of a charged particle is classically forbidden but can proceed by WKB tunneling, with a suppression that grows with black-hole size and (mostly...

  17. Breaking Free from the Swampland of Impossible Universes through the DESI Portal

    astro-ph.CO 2026-05 unverdicted novelty 3.0

    DESI data favoring time-evolving dark energy may place constant-Λ cosmology in the string swampland and favor string-inspired dynamical dark energy.

  18. Modave lectures on energy conditions in quantum field theory and semi-classical gravity

    hep-th 2026-05 accept novelty 2.0

    Review of classical energy conditions, their quantum violations, and information-theoretic bounds for semi-classical gravity, based on Modave lectures.

  19. Breaking Free from the Swampland of Impossible Universes through the DESI Portal

    astro-ph.CO 2026-05 unverdicted novelty 2.0

    A review summarizing advancements over the past two years that link DESI baryon acoustic oscillation data to string-inspired scenarios with dynamic dark energy.

  20. Breaking Free from the Swampland of Impossible Universes through the DESI Portal

    astro-ph.CO 2026-05 unverdicted novelty 2.0

    DESI data indicating evolving dark energy may allow string theory to describe observed universes without violating swampland constraints on constant dark energy.

  21. Breaking Free from the Swampland of Impossible Universes through the DESI Portal

    astro-ph.CO 2026-05 unverdicted novelty 2.0

    A review of string-inspired dynamical dark energy models claiming compatibility with DESI's hints of evolving dark energy under swampland constraints.