arXiv subjects

Boudhayan Paul

Publications and source records attributed to Boudhayan Paul.

11 recordsLinked to original sources

arXiv2023

Covariant odd entanglement entropy in AdS$_3$/CFT$_2$

We advance a covariant construction for the holographic odd entanglement entropy (OEE) of time dependent bipartite states in CFT$_2$s dual to bulk AdS$_3$ geometries. In this context we obtain the OEE for bipartite states in zero, finite temperature and finite size CFT$_2$s dual to bulk pure AdS$_3$ and BTZ black hole geometries through appropriate replica techniques. The replica technique results for the time dependent OEE are reproduced modulo constants in the large central charge limit through holographic computations involving the bulk entanglement wedge cross section (EWCS). Subsequently we obtain the time dependent OEE for bipartite states in zero and finite temperature CFT$_2$s with a conserved charge dual to bulk extremal and non-extremal rotating BTZ black holes through both field theory and covariant holographic computations which again match up to constants in the large central charge limit.

hep-th↗

arXiv2023

Holographic entanglement negativity for a single subsystem in conformal field theories with a conserved charge

We utilize a holographic construction to compute the entanglement negativity for bipartite mixed state configurations of a single subsystem in $CFT_d$s with a conserved charge dual to bulk $AdS_{d+1}$ geometries. In this context, we obtain the holographic entanglement negativity for single subsystems with long rectangular strip geometries in $CFT_d$s with a conserved charge dual to bulk non extremal and extremal Reissner-Nordström (RN)-$AdS_{d+1}$ black holes at the leading order in a perturbation theory. We demonstrate that the holographic entanglement negativity computed involves the elimination of thermal contributions at the leading order confirming earlier results in the literature. This also conforms to quantum information theory expectations and constitutes further consistency checks for the holographic construction.

hep-th↗

arXiv2023

Odd entanglement entropy in $\text{T}\bar{\text{T}}$ deformed CFT$_2$s and holography

We construct a replica technique to perturbatively compute the odd entanglement entropy (OEE) for bipartite mixed states in $\text{T}\bar{\text{T}}$ deformed CFT$_2$s. This framework is then utilized to obtain the leading order correction to the OEE for two disjoint intervals, two adjacent intervals, and a single interval in $\text{T}\bar{\text{T}}$ deformed thermal CFT$_2$s in the large central charge limit. The field theory results are subsequently reproduced in the high temperature limit from holographic computations for the entanglement wedge cross sections in the dual bulk finite cut-off BTZ geometries. We further show that for finite size $\text{T}\bar{\text{T}}$ deformed CFT$_2$s at zero temperature the corrections to the OEE are vanishing to the leading order from both field theory and bulk holographic computations.

hep-th↗

arXiv2023

Entanglement negativity in $\text{T}\bar{\text{T}}$-deformed CFT$_2$s

We apply a suitable replica technique to develop a perturbative expression for the entanglement negativity of bipartite mixed states in T$\overline{\text{T}}$-deformed CFT$_2$s up to the first order in the deformation parameter. Utilizing our perturbative construction we compute the entanglement negativity for various bipartite mixed states involving two disjoint intervals, two adjacent intervals, and a single interval in a T$\overline{\text{T}}$-deformed CFT$_2$ at a finite temperature, in the large central charge limit. Subsequently, we advance appropriate holographic constructions to compute the entanglement negativity for such bipartite states in T$\overline{\text{T}}$-deformed thermal CFT$_2$s dual to BTZ black holes in a finite cut-off bulk geometry and find agreement with the corresponding field theoretic results in the limit of small deformation parameter.

hep-th↗

arXiv2021

Covariant holographic negativity from the entanglement wedge in AdS$_3/$CFT$_2$

We propose a covariant holographic construction based on the extremal entanglement wedge cross section, for the entanglement negativity of bipartite states in $CFT_{1+1}$s dual to non static bulk $AdS_3$ geometries. Utilizing our proposal we obtain the holographic entanglement negativity for bipartite mixed states in $CFT_{1+1}$s dual to bulk extremal and non extremal rotating BTZ black holes and the time dependent Vaidya-$AdS_3$ geometries. Our results correctly reproduce the replica technique results modulo certain constants for the corresponding dual $CFT_{1+1}$s in the large central charge limit for the bulk black hole geometries. Furthermore for all the cases our results also match upto such constants with the corresponding results from an earlier alternate covariant holographic construction in the literature. This demonstrates the equivalence modulo constants of the two constructions for the $AdS_3/CFT_2$ scenario.

hep-th↗

arXiv2020

On minimal entanglement wedge cross section for holographic entanglement negativity

We demonstrate the equivalence of two different conjectures in the literature for the holographic entanglement negativity in AdS$_3$/CFT$_2$, modulo certain constants. These proposals involve certain algebraic sums of bulk geodesics homologous to specific combinations of subsystems, and the entanglement wedge cross section (EWCS) backreacted by a cosmic brane for the conical defect geometry in the bulk gravitational path integral. It is observed that the former conjectures reproduce the field theory replica technique results in the large central charge limit whereas the latter involves constants related to the Markov gap. In this context we establish an alternative construction for the EWCS of a single interval in a CFT$_2$ at a finite temperature to resolve an issue for the latter proposal involving the thermal entropy elimination for the holographic entanglement negativity. Our construction for the EWCS correctly reproduces the corresponding field theory results modulo the Markov gap constant in the large central charge limit.

hep-th↗

arXiv2020

Holographic entanglement negativity for disjoint subsystems in $\mathrm{AdS_{d+1}/CFT_d}$

We propose a construction to compute the holographic entanglement negativity for bipartite mixed state configurations of two disjoint subsystems in higher dimensional conformal field theories (CFT$_d$s) dual to bulk AdS$_{d+1}$ geometries. Our proposal follows from the corresponding AdS$_3$/CFT$_2$ scenario and involves an algebraic sum of the areas of bulk RT surfaces for certain combinations of subsystems. Utilizing our construction we compute the holographic entanglement negativity at the leading order through a perturbative expansion, for such bipartite mixed states of two disjoint subsystems with long rectangular strip geometries in CFT$_d$s dual to bulk pure AdS$_{d+1}$ geometries and AdS$_{d+1}$-Schwarzschild black holes.

hep-th↗

arXiv2019

Entanglement negativity in Galilean conformal field theories

We obtain the entanglement negativity for various bipartite zero and finite temperature pure and mixed state configurations in a class of $(1+1)$-dimensional Galilean conformal field theories. In this context we establish a construction for computing the entanglement negativity for such bipartite states involving a suitable replica technique. Our construction exactly reproduces certain universal features observed for entanglement negativity of corresponding states in relativistic $(1+1)$-dimensional conformal field theories.

hep-th↗

arXiv2019

Covariant holographic entanglement negativity for disjoint intervals in $AdS_3/CFT_2$

We advance a construction for the covariant holographic entanglement negativity for time dependent mixed states of disjoint intervals in $(1+1)$ dimensional conformal field theories ($CFT_{1+1}$) dual to bulk non static $AdS_3$ geometries. Application of our proposal to such mixed states in a $CFT_{1+1}$ dual to bulk non extremal and extremal rotating BTZ black holes exactly reproduces the replica technique results in the large central charge limit. We also investigate the time dependent holographic entanglement negativity for such mixed states in a $CFT_{1+1}$ dual to a bulk Vaidya-$AdS_3$ geometry in the context of their thermalization involving bulk black hole formation.

hep-th↗

arXiv2019

Holographic entanglement negativity for disjoint intervals in $AdS_3/CFT_2$

We advance a holographic construction for the entanglement negativity of bipartite mixed state configurations of two disjoint intervals in $(1+1)$ dimensional conformal field theories ($CFT_{1+1}$) through the $AdS_3/CFT_2$ correspondence. Our construction constitutes the large central charge analysis of the entanglement negativity for mixed states under consideration and involves a specific algebraic sum of bulk space like geodesics anchored on appropriate intervals in the dual $CFT_{1+1}$. The construction is utilized to compute the holographic entanglement negativity for such mixed states in $CFT_{1+1}$s dual to bulk pure $AdS_3$ geometries and BTZ black holes respectively. Our analysis exactly reproduces the universal features of corresponding replica technique results in the large central charge limit which serves as a consistency check.

hep-th↗

arXiv2015

Understanding spin Hall effect in two-dimensional fermionic systems with generic spin-orbit interaction

We delve into spin Hall effect in generic spin-orbit coupled two-dimensional fermionic systems. We derive analytically the spin-orbit force responsible for the spin Hall effect, and find that it has `Lorentz force'-like form. We also derive the pseudo magnetic field responsible for this force. We establish the relation between the spin Hall conductivity, flux quanta and this pseudo magnetic field, similar to the one between charge Hall conductivity, flux quanta and the external field. We also present an exact closed-form expression of the spin Hall conductivity in a generic spin-orbit coupled system. Depending on the dimensionality of the spin-orbit interactions, the spin Hall conductivity depends on different combinations of Rashba parameter and fermion density.

cond-mat.mes-hall↗