arXiv subjects

Himanshu Chourasiya

Publications and source records attributed to Himanshu Chourasiya.

7 recordsLinked to original sources

arXiv2025

Holographic Entanglement Entropy in Janus deformed AdS$_3$ Geometries

We investigate the time dependent entanglement entropy for boosted single intervals in interface conformal field theories (ICFT$_2$s) dual to Janus deformed AdS$_3$ geometries. For a Janus deformed Poincaré AdS$_3$ background, we obtain the entanglement entropy and a Janus induced correction using a replica technique for the equivalent dual field theory described on a conformally flat background on corresponding AdS$_2$ slices on the asymptotic boundary. The holographic entanglement entropy is then computed through certain embedding relations for the bulk Janus deformed AdS$_3$ geometry which exactly match with the field theory results. We further extend our analysis to investigate the entanglement entropy of corresponding intervals in ICFT$_2$s dual to bulk Janus deformed BTZ black hole and AdS$_3$ black string geometries obtaining consistent results from both the field theoretic and bulk computations.

hep-th↗

arXiv2025

Bridging Boundaries: $T\bar{T}$, Double Holography, and Reflected Entropy

We investigate the reflected entropy for bipartite mixed state configurations in a $T\bar{T}$ deformed boundary conformal field theory in $2$ dimensions (BCFT$_2$). The bulk dual is described by asymptotically AdS$_3$ geometries with the cut off surface pushed deeper into the bulk and truncated by an end of the world brane. We obtain the reflected entropy up to a linear order in the radial cut-off for static and time dependent configurations involving an eternal black hole, from the island and defect extremal surface (DES) prescriptions in the context of the deformed AdS/BCFT. We observe agreement of the leading order correction for all cases between the two prescriptions. We also obtain the analogous of the Page curves for the reflected entropy and investigate the modification due to the $T\bar{T}$ deformation.

hep-th↗

arXiv2025

Reflected entropy and islands in a braneworld cosmology

This work investigates the nature of mixed state entanglement and correlation in a braneworld cosmological model, where the bulk geometry is described by an eternal BTZ black hole truncated by an end-of-the-world brane representing a Friedmann-Robertson-Walker (FRW) cosmology. We explore the holographic reflected entropy for both adjacent and disjoint subsystems using the island prescription and the defect extremal surface prescription. In the large central charge limit, we demonstrate that both prescriptions yield an exact agreement. Additionally, we analyze the time evolution of reflected entropy and holographic mutual information, along with an analysis of the geometric Markov gap. Our study provides new insights into the role of quantum extremal surfaces in probing black hole interiors and cosmological spacetimes, with implications for understanding mixed state entanglement and quantum information dynamics in holographic cosmological models.

hep-th↗

arXiv2023

Reflected entropy in BCFTs on a black hole background

We obtain the reflected entropy for bipartite mixed state configurations involving two disjoint and adjacent subsystems in two dimensional boundary conformal field theories (BCFT$_2$s) in a black hole background. The bulk dual is described by an AdS$_3$ black string geometry truncated by a Karch-Randall brane. The entanglement wedge cross section computed for this geometry matches with the reflected entropy obtained for the BCFT$_2$ verifying the holographic duality. In this context, we also obtain the analogues of the Page curves for the reflected entropy and investigate the behaviour of the Markov gap.

hep-th↗

arXiv2022

Covariant holographic reflected entropy in $AdS_3/CFT_2$

We substantiate a covariant proposal for the holographic reflected entropy in $CFT$s dual to non-static $AdS$ geometries from the bulk extremal entanglement wedge cross section in the literature with explicit computations in the $AdS_3/CFT_2$ scenario. In this context we obtain the reflected entropy for zero and finite temperature time dependent bipartite mixed states in $CFT_{1+1}$s with a conserved charge dual to bulk rotating extremal and non-extremal BTZ black holes through a replica technique. Our results match exactly with the corresponding extremal entanglement wedge cross section for these bulk geometries in the literature. This constitutes a significant consistency check for the proposal and its possible extension to the corresponding higher dimensional $AdS/CFT$ scenario.

hep-th↗

arXiv2022

Odd entanglement entropy in Galilean conformal field theories and flat holography

The odd entanglement entropy (OEE) for bipartite states in a class of $(1+1)$-dimensional Galilean conformal field theories ($GCFT_{1+1}$) is obtained through an appropriate replica technique. In this context our results are compared with the entanglement wedge cross section (EWCS) for $(2+1)$-dimensional asymptotically flat geometries dual to the $GCFT_{1+1}$ in the framework of flat holography. We find that our results are consistent with the duality of the difference between the odd entanglement entropy and the entanglement entropy of bipartite states, with the bulk EWCS for flat holographic scenarios.

hep-th↗

arXiv2022

Reflected entropy in Galilean conformal field theories and flat holography

We obtain the reflected entropy for bipartite states in a class of $(1+1)$-dimensional Galilean conformal field theories ($GCFT_{1+1}$) through a replica technique. Furthermore we compare our results with the entanglement wedge cross section (EWCS) obtained for the dual (2+1) dimensional asymptotically flat geometries in the context of flat holography. We find that our results are consistent with the duality between the reflected entropy and the bulk EWCS for flat holographic scenarios.

hep-th↗