arXiv subjects

Shivrat Sachdeva

Publications and source records attributed to Shivrat Sachdeva.

3 recordsLinked to original sources

arXiv2025

A survey of knots and quivers

This survey explores knot polynomials and their categorification, culminating in the homological invariants of knots. We begin with an overview of classical knot polynomials, progressing towards the superpolynomial and its role in unifying various knot homologies. Along the way, we provide physical and geometric insights into the unification of the $sl(N)$ Khovanov-Rozansky and the knot Floer homology. We then turn our attention to the intriguing correspondence between knots and quivers, examining how this perspective sheds light on the integrality of BPS states encoded in the Labastida-Mari\~no-Ooguri-Vafa (LMOV) invariants. We will further investigate the knot-quiver correspondence from a physics and geometric side and study the 3d $\mathcal{N}=2$ theory $T[Q_K]$ for the quivers.

math.GT↗

arXiv2024

Study of Information Restoring Effects in Virasoro Blocks

It is well-known that in the large central charge $c$ limit, the Virasoro blocks in CFT$_2$ suffer from information loss when studying the BTZ black holes in the dual AdS$_3$ theory. Recent studies have proved that non-perturbative $e^{-c}$ corrections resolves information loss. Here, we study universal features of the spectrum of heavy states from general properties of finite $c$ Virasoro conformal blocks. Furthermore, we investigate the behavior of correlators beyond "Page" time $ t \sim S_{BH}$, entropy of the black hole. In the Lorentzian regime, we wish to better understand the transition from an exponential decay behaviour of Virasoro blocks in the heavy-light limit to a power-law decay at late times.

hep-th↗

arXiv2023

Bulk reconstruction using timelike entanglement in (A)dS

It is well-known that the entanglement entropies for spacelike subregions, and the associated modular Hamiltonians play a crucial role in the bulk reconstruction program within Anti de-Sitter (AdS) holography. Explicit examples of HKLL map exist mostly for the cases where the emergent bulk region is the so-called entanglement wedge of the given boundary subregion. However, motivated from the complex pseudo-entropy in Euclidean conformal field theories (CFT), one can talk about a `timelike entanglement' in Lorentzian CFTs dual to AdS spacetimes. One can then utilize this boundary timelike entanglement to define a boundary `timelike modular Hamiltonian'. We use constraints involving these Hamiltonians in a manner similar to how it was used for spacelike cases, and write down bulk operators in regions which are not probed by an RT surface corresponding to a single CFT. In the context of two dimensional CFT, we re-derive the HKLL formulas for free bulk scalar fields in three examples: in AdS Poincar\'{e} patch, inside and outside of the AdS black hole, and for de Sitter flat slicings. In this method, one no longer requires the knowledge of bulk dynamics for sub-horizon holography.

hep-th↗