Damghan University PressJournal of Holography Applications in Physics2783-47787120260713Is Time Reversal in de Sitter Space a Spontaneously Broken Gauge Symmetry?114211410.22128/jhap.2026.3294.1203ENLeonard SusskindLITP and Department of Physics, Stanford University, Stanford, CA 94305-4060, USA;
Google, Mountain View, CA, USAJournal Article20260319I'll begin with some well-deserved acknowledgements: I am grateful to Daniel Harlow for discussions of time-reversal holonomies. I have also benefited from a long ongoing correspondence with Edward Witten, but frankly in both cases I can't tell whether they agree with me or not. I have often been accused of imprecision, especially toward the later parts of a paper, where I expect that my readers have ``caught on." That does eventually happen-the readers catching on and I thank them-but I'm now almost 86 and I can't wait. So I've tried to maintain a level of conceptual if not mathematical rigor throughout. Mathematical rigor(mortis) can sometimes be the enemy of conceptual clarity. I thank my friend Richard Feynman for reminding me of that lesson. Finally I thank the chatbot who gave me the definition of scaffold in section 1.3. It was better than anything I was able to do. Symmetries of a Holographic theory; whether continuous or discrete, local or global, are gauge symmetries of the bulk. This includes discrete space-time symmetries such as C and P. But time-reversal is sufficiently different from other symmetries that we may question the standard wisdom and ask whether symmetries involving T should be gauged in the bulk. Harlow and Numasawa [1] say yes; time-reversal is a gauge symmetry. Witten [2] says no: time reversal is different and does not manifest as a gauge symmetry of the bulk. My view is-yes-but with a twist: Time-reversal is indeed a gauge symmetry; but it is hidden by spontaneous symmetry breaking. In this paper I will review the case for spontaneous symmetry breaking of time-reversal and explain the ``smoking gun"-a closed curve and a holonomy which flips forward-going clocks to backward going clocks, and vice versa.https://jhap.du.ac.ir/article_2114_1cbe6952e862912830b9a6252da97c39.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260713Hayward-Kalb-Ramond AdS Black Holes with a Cloud of Strings: Geometry, Thermodynamic Topology, Photon-Sphere Observables, and Wave Dynamics1539213310.22128/jhap.2026.3332.1207ENİzzet SakallıPhysics Department, Eastern Mediterranean University, Famagusta 99628, North Cyprus via Mersin 10, Turkiye0000-0001-7827-9476Journal Article20260526We construct a static spherically symmetric black hole (BH) solution in Kalb-Ramond (KR) gravity that simultaneously hosts a Hayward magnetic-monopole regular core, a Letelier cloud of strings (CoS), and an anti-de Sitter (AdS) asymptote with the cosmological constant identified as thermodynamic pressure. The lapse function $f(r)=(1-\alpha_{s})/(1-\ell)-2Mr^{2}/[(1-\ell)(r^{3}+g^{3})]+8\pi P r^{2}/[3(1-\ell)]$ carries four independent parameters with transparent physical roles: the KR Lorentz-violation (LV) parameter $\ell$ rescales the asymptotic potential, the Hayward length $g$ removes the central singularity, the CoS deficit $\alpha_{s}$ deforms the solid angle, and $P=-\Lambda/8\pi$ sets the AdS curvature. Symbolic verification confirms regularity of every curvature invariant at $r=0$, with $f(r)$ admitting a finite limit and reducing to the Ditta {\it et al.} (JHEAP 2025) solution as $g\to 0$, $\alpha_{s}\to 0$. We work out the horizon structure, photon sphere $r_{\rm ph}$ and shadow radius $r_{\rm sh}$, weak-deflection lensing via the Gauss-Bonnet theorem (GBT), innermost stable circular orbits (ISCO), Hawking temperature, Bekenstein-Hawking entropy, heat capacity, Gibbs free energy, $P$-$V$ criticality, Joule-Thomson (JT) inversion, and the eikonal quasinormal-mode (QNM) spectrum. The Van der Waals (VdW) critical point exists across the whole window of $g$ tested above $g\to 0$, with the universal ratio $\rho_{c}\equiv P_{c}v_{c}/T_{c}$ depending on $\ell$ alone through the factorisation $\rho_{c}=(1-\ell)\,\rho_{c}^{\rm Hay\text{-}AdS}$ with $\rho_{c}^{\rm Hay\text{-}AdS}=0.39303$, so that the reference $(\alpha_{s},\ell)=(0.05,0.10)$ configuration gives $\rho_{c}=0.354$, $5.6\%$ below the standard $3/8$ value of the charged-AdS class. The Wei-Liu-Mann thermodynamic-topology classification places the solution in the $W=+1$ topological class, the same as Reissner-Nordstr\"om-AdS (RN-AdS): three BH branches appear below $\tau_{c}$ with windings $\{+1,-1,+1\}$, merge at $\tau_{c}$, and reduce to one $W=+1$ branch above $\tau_{c}$. The numerical analysis shows that $\alpha_{s}$ and $\ell$ act on photon and scalar-wave barriers in opposite directions. The combined dependence makes the four parameters separately identifiable in principle from a joint shadow-ringdown measurement at Event Horizon Telescope (EHT) angular resolution and LIGO/Virgo ringdown sensitivity.https://jhap.du.ac.ir/article_2133_cc789ba808273a094dede8e009803086.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260713A Dynamical Realization of Holography in Cosmology from Hyperbolic General Relativity: Explicit Dimensional Reduction via Curvature-Generated Shock Relaxation4063211810.22128/jhap.2026.3236.1188ENJack KipermanDepartment of Physics, Portland State University, P.O. Box 751, Portland, Oregon, USA 972070000-0002-1951-6328Journal Article20260131Holography asserts that the dynamics of a gravitational system may be determined by degrees of freedom associated with a lower-dimensional structure, rather than by independent volumetric variables. While this principle is well established in boundary-based constructions, its realization in cosmology has remained elusive due to the absence of fixed asymptotic boundaries. In this work, we present an explicit realization of holography in cosmology arising directly from the hyperbolic structure of general relativity. We show that the nonlinear evolution of the Einstein equations coupled to a scalar field generically produces a global control structure identified with the cosmological apparent horizon. By applying the Unified First Law of Thermodynamics ($-dE = T\,dS$) to this horizon, we obtain a geometric closure for the net exchange flux $Q$ under the explicit assumption that the only energy exchange between the bulk and the auxiliary (unresolved) sector is mediated through the apparent-horizon screen, constraining the bulk energy density to scale as $\rho \propto L^{-2}$ and thereby imposing a Bekenstein-Hawking area law ($S \propto A$) on the bulk entropy. We demonstrate that bulk cosmological observables -- including the expansion history and late-time acceleration -- are functionals of this codimension-one structure rather than independent volumetric degrees of freedom. The construction constitutes a concrete, equation-level realization of holography in cosmology, achieved via dynamical dimensional reduction of the phase space.https://jhap.du.ac.ir/article_2118_f2bf93fcf72b07d68f6ece73bbc0d6e4.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260713GUP-Deformed Thermodynamic Behavior of Cylindrical Black Strings in Four Dimensions6480210710.22128/jhap.2026.3211.1184ENNadeem Ul Islam RatherDepartment of Physics, NIT Srinagar, Jammu and Kashmir, India0000-0001-9978-6426Khaja Zuber AminDepartment of Physics, NIT Srinagar, Jammu and Kashmir, India0009-0009-3943-5208H. KaurDepartment of Physics, NIT Srinagar, Jammu and Kashmir, IndiaPrince A. GanaiDepartment of Physics, NIT Srinagar, Jammu and Kashmir, India0000-0002-7896-9183Journal Article20260102We investigate the thermodynamic properties of four-dimensional cylindrically symmetric black strings embedded in an Anti-de Sitter (AdS) spacetime. By incorporating the Generalized Uncertainty Principle (GUP), we introduce minimal length corrections to the thermodynamic framework, thereby capturing quantum gravity effects in the near-horizon regime. We demonstrate that these GUP-induced modifications lead to logarithmic corrections in the entropy-area relation, particularly for small horizon radii, while preserving thermodynamic consistency with the first law of thermodynamics. Through a detailed analysis of the Helmholtz and Gibbs free energies, we observe that the equation of state is significantly deformed by quantum corrections, driving instabilities in black strings with sufficiently small horizon radii. The study of specific heat capacity further confirms a phase transition from stable to unstable configurations, highlighting the role of the minimal length scale on the thermal stability of black string systems.https://jhap.du.ac.ir/article_2107_cb4168c04922d97a37f6c8c8847330c5.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260701Photonic Exceptional Points in Holography and QCD381141212210.22128/jhap.2026.3292.1202ENMahdis GhodratiInternational Centre for Theoretical Physics Asia-Pacific, University of Chinese Academy of Sciences, 100190 Beijing, China0000-0001-8724-6182Journal Article20260319In this work, based on an analogy with holographic confining geometries and using complexified fields, we build a holographic toy model of third order photonic exceptional points (EPs) of ternary coupled microrings with gain and loss, which makes an open, non-Hermitian quantum system. In our model, we discuss the Ferrell-Glover-Tinkham sum rule for various combinations of gain and loss systems, and numerically find the behavior of spectra which matches with the experiments. We also discuss the inhomogeneous case of a holographic lattice for three-site photonic EPs. Additionally, we numerically find the behavior of phase rigidity and the Petermann factor around EPs versus various parameters of the model. We also discuss the connections between recent developments in complexified, time-dependent entanglement entropy and EPs, and then, we connect EPs and the $\theta$-vacuum of QCD through topological structures, partition functions, and winding numbers, and find a second-order EP in a perturbed $\theta$-vacuum model. Finally, we examined a controlled non-Hermitian deformation of $\theta$-vacuum toy model, by using the Lindblad formalism and Liouvillian eigenvalues.https://jhap.du.ac.ir/article_2122_7a54a6a493473d421928106bc1d152f6.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260701The Big Bang Firewall and the Emergence of Spacetime142161212410.22128/jhap.2026.3270.1198ENFaical BarziLPTHE, Physics Department, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco;
CRMEF, Regional Center for Education and Training Professions, Marrakesh, MoroccoHasan El MoumniLPTHE, Physics Department, Faculty of Sciences, Ibnou Zohr University, Agadir, Morocco0000-0001-7408-0910Karima MasmarLPTHE, Physics Department, Faculty of Sciences, Ibnou Zohr University, Agadir, MoroccoJournal Article20260218We propose that the Big Bang can be understood as a cosmic-scale entanglement transition occurring in a pre-geometric quantum state. Motivated by the black hole information paradox and the AMPS argument, we interpret the pre-Bang phase as an over-constrained entanglement structure producing a monogamy tension, rather than a fundamental violation of quantum mechanics. The resulting cosmic firewall is not a localized destructive barrier, but a global reorganization of quantum correlations that preserves fine-grained unitarity while allowing the emergence of semiclassical spacetime. We model the pre-Bang substrate as a quantum graph whose highly connected phase encodes dense pre-geometric correlations. Within a semiclassical approximation, the replica trick applied to the gravitational path integral leads to an entanglement--cosmology scaling relation linking variations of entanglement entropy to variations of the effective cosmological constant through the normalized spacetime volume of the emergent background. This scaling is consistent with the known dependence of de Sitter entropy on the cosmological constant. The framework provides a unitary information-theoretic mechanism for spacetime emergence, connects the thermodynamic arrow of time to post-transition entanglement growth, and extends the firewall paradigm from black hole horizons to cosmological initial conditions. It also suggests possible observational windows in primordial non-Gaussianities, stochastic gravitational-wave backgrounds, and ultra-slow variations of effective couplings.https://jhap.du.ac.ir/article_2124_019b68e92c3e5dac9bce571c332b7a02.pdfDamghan University PressJournal of Holography Applications in Physics2783-47787120260713AdS/CFT Correspondence: The Fountain of Quantum Youth162167211510.22128/jhap.2026.3172.1171ENOvidiu RacoreanGeneral Direction of Information Technology, Banul Antonache str. 52-60, sc.C, ap.19, Bucharest, Romania0000-0002-9462-007XJournal Article20251130We argue, in the context of AdS/CFT correspondence, that the structure of the geometry dual to two entangled CFTs is a time non-orientable spacetime. Further, we elevate this argument to any entangled quantum system. Accordingly, we should expect entangled quantum systems (particles in a subsidiary) not to experience the flow of time. As a result, the lifetimes of the entangled particles should be considerably longer than those of their unentangled counterparts. https://jhap.du.ac.ir/article_2115_b6d19675719c05d4ce6a0e30536be891.pdf