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Related papers: Comparison theorems for causal diamonds

200 papers

We apply a recent proposal for a distinguished ground state of a quantum field in a globally hyperbolic spacetime to the free massless scalar field in a causal diamond in two-dimensional Minkowski space. We investigate the two limits in…

High Energy Physics - Theory · Physics 2020-12-25 Niayesh Afshordi , Michel Buck , Fay Dowker , David Rideout , Rafael D. Sorkin , Yasaman K. Yazdi

We study the discrete causal set geometry of a small causal diamond in a curved spacetime using the average abundance of k-element chains or total orders in the underlying causal set C. We begin by obtaining the first order curvature…

General Relativity and Quantum Cosmology · Physics 2013-03-14 Mriganko Roy , Debdeep Sinha , Sumati Surya

We develop the non-perturbative reduced phase space quantization of causal diamonds in (2+1)-dimensional gravity with a nonpositive cosmological constant. In Part I we described the classical reduction process and the reduced phase space,…

High Energy Physics - Theory · Physics 2025-07-30 Rodrigo Andrade e Silva

This dissertation investigates thermodynamic, emergent and holographic aspects of gravity in the context of causal diamonds. We obtain a gravitational first law for causal diamonds in maximally symmetric spacetimes and argue that these…

High Energy Physics - Theory · Physics 2019-08-16 Manus R. Visser

Causal diamonds are known to have thermal behavior that can be probed by finite-lifetime observers equipped with energy-scaled detectors. This thermality can be attributed to the time evolution of observers within the causal diamond,…

Quantum Physics · Physics 2025-01-03 H. E. Camblong , A. Chakraborty , P. Lopez-Duque , C. Ordóñez

We show that the linearized higher derivative gravitational field equations are equivalent to an equilibrium condition on the entanglement entropy of small spherical regions in vacuum. This extends Jacobson's recent derivation of the…

High Energy Physics - Theory · Physics 2017-02-15 Pablo Bueno , Vincent S. Min , Antony J. Speranza , Manus R. Visser

We define a one-parameter family of canonical volume measures on Lorentzian (pre-)length spaces. In the Lorentzian setting, this allows us to define a geometric dimension - akin to the Hausdorff dimension for metric spaces - that…

Mathematical Physics · Physics 2023-09-26 Robert J. McCann , Clemens Sämann

Thanks to a local interpetation of the KMS condition, the mapping from (unbounded) wedge regions of Minkowski space-time to (bounded) double-cone regions is extended to the Unruh temperature associated to relevant observers in both regions.…

General Relativity and Quantum Cosmology · Physics 2009-07-22 Pierre Martinetti

We present a new method for embedding a causal set into Minkowski spacetime. The method is similar to a previously presented method, but is simpler and provides better embedding results. The method uses spacetime volumes to define causal…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Steven Johnston

We argue that the correlation between the modular Hamiltonians of two causal diamonds related by a finite time translation is equal to the uncertainty in the modular Hamiltonian of the diamond in their overlap. In a separate section we…

High Energy Physics - Theory · Physics 2023-12-01 T. Banks , W. Fischler

In a previous paper we obtained formulae for the volume of a causal diamond or Alexandrov open set $I^+(p) \cap I^-(q)$ whose duration $\tau(p,q) $ is short compared with the curvature scale. In the present paper we obtain asymptotic…

High Energy Physics - Theory · Physics 2008-11-26 G. W. Gibbons , S. N. Solodukhin

We show that the simplicity constraints, which define the dynamics of spin foam models, imply, and are implied by, the first law of thermodynamics, when the latter is applied to causal diamonds in the quantum spacetime. This result reveals…

General Relativity and Quantum Cosmology · Physics 2017-11-29 Lee Smolin

We study quantum fluctuations in the lightcone metric of the 4-d Einstein-Hilbert action via dimensional reduction to Jackiw-Teitelboim (JT) gravity. In particular, we show that, in Einstein gravity, the causal development of a region in…

High Energy Physics - Theory · Physics 2023-01-16 Sergei Gukov , Vincent S. H. Lee , Kathryn M. Zurek

We analyze properties of the Sp(2M) conformally invariant field equations in the recently proposed generalized $\half M(M+1)$-dimensional space-time $\M_M$ with matrix coordinates. It is shown that classical solutions of these field…

High Energy Physics - Theory · Physics 2016-11-23 M. A. Vasiliev

We prove a globally hyperbolic spacetime with locally Lipschitz continuous metric and timelike distributional Ricci curvature bounded from below obeys the timelike measure contraction property. The remarkable class of examples of spacetimes…

Differential Geometry · Mathematics 2026-03-26 Mathias Braun , Marta Sálamo Candal

We present a theory of accelerated observers in the formalism of holographic space time, and show how to define the analog of the Unruh effect for a one parameter set of accelerated observers in a causal diamond in Minkowski space. The key…

High Energy Physics - Theory · Physics 2020-01-23 Tom Banks , Willy Fischler

We adapt the axioms of the quantum mechanics to the quantum Minkowski space-time coordinates and their transformations under the quantum Lorentz group to show how we can formulate the noncommutative special relativity and its quantum…

Mathematical Physics · Physics 2007-05-23 M. Lagraa

We explore the idea of asymptotic silence in causal set theory and find that causal sets approximated by continuum spacetimes exhibit behaviour akin to asymptotic silence. We make use of an intrinsic definition of spatial distance between…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Astrid Eichhorn , Sebastian Mizera , Sumati Surya

We present a novel derivation of both the Minkowski metric and Lorentz transformations from the consistent quantification of a causally ordered set of events with respect to an embedded observer. Unlike past derivations, which have relied…

Mathematical Physics · Physics 2014-12-22 Kevin H. Knuth , Newshaw Bahreyni

We show that the definition of global hyperbolicity in terms of the compactness of the causal diamonds and non-total imprisonment can be extended to spacetimes with continuous metrics, while retaining all of the equivalences to other…

Differential Geometry · Mathematics 2019-11-20 Clemens Sämann