papers

Publications (16)

hep-th2025

Reduced Half-sided Translations and Islands

Krishna Jalan, Roji Pius

An AdS black hole in equilibrium with a finite temperature non-gravitating bath comes with a Hawking-like information paradox. The resolution of this paradox requires introduci…

hep-th2022

Hyperbolic Geometry of Superstring Perturbation Theory

Seyed Faroogh Moosavian, Roji Pius

We explore the hyperbolic structure of the RNS formulation of perturbative superstring theory. The aim is to provide a systematic method to explicitly compute on-shell and off-shel…

hep-th2025

Gauge Theory Amplitudes from Cubic Scalar Feynman diagrams

Roji Pius

Feynman diagrams are the foremost tool in the perturbative study of quantum field theory. In gauge theories, the full potential of this tool is revealed when it is combined with th…

hep-th2018

Quantum Closed Superstring Field Theory and Hyperbolic Geometry I: Construction of String Vertices

Roji Pius

The complete quantum theory of closed superstrings is constructed using string diagrams endowed with metric having constant curvature . The elementary string diagrams are equip…

hep-th2014

Mass Renormalization in String Theory: General States

Roji Pius, Arnab Rudra, Ashoke Sen

In a previous paper we described a procedure for computing the renormalized masses and S-matrix elements in bosonic string theory for a special class of massive states which do not…

hep-th2025

Island Paradigm and Information Recovery from Radiation

Krishna Jalan, Roji Pius, Manish Ramchander

The island paradigm for an AdS eternal black hole in the Hartle-Hawking state coupled to a finite temperature non-gravitating bath asserts that after the Page time the operator…

hep-th2018

Cutkosky Rules for Superstring Field Theory

Roji Pius, Ashoke Sen

Superstring field theory expresses the perturbative S-matrix of superstring theory as a sum of Feynman diagrams each of which is manifestly free from ultraviolet divergences. The i…

hep-th2013

S-duality Improved Perturbation Theory in Compactified Type I / Heterotic String Theory

Roji Pius, Ashoke Sen

We study the mass of the stable non-BPS state in type I / heterotic string theory compactified on a circle with the help of the interpolation formula between weak and strong coupli…

hep-th2019

Hyperbolic Geometry and Closed Bosonic String Field Theory I: The String Vertices Via Hyperbolic Riemann Surfaces

Seyed Faroogh Moosavian, Roji Pius

The main geometric ingredient of the closed string field theory are the string vertices, the collections of string diagrams describing the elementary closed string interactions, sa…

hep-th2023

Theory dependence of black hole interior reconstruction and the extended strong subadditivity

Sitender Pratap Kashyap, Roji Pius, Manish Ramchander

An AdS eternal black hole in equilibrium with a finite temperature bath presents a Hawking-like information paradox due to a continuous exchange of radiation with the bath. The non…

hep-th2018

Unitarity of the Box Diagram

Roji Pius, Ashoke Sen

The complete proof of cutting rules needed for proving perturbative unitarity of quantum field theories usually employs the largest time equation or old fashioned perturbation theo…

hep-th2019

Topological string entanglement

Veronika E. Hubeny, Roji Pius, Mukund Rangamani

We investigate how topological entanglement of Chern-Simons theory is captured in a string theoretic realization. Our explorations are motivated by a desire to understand how quant…

hep-th2019

Hyperbolic Geometry and Closed Bosonic String Field Theory II: The Rules for Evaluating the Quantum BV Master Action

Seyed Faroogh Moosavian, Roji Pius

The quantum Batalian-Vilkovisky master action for closed string field theory consists of kinetic term and infinite number of interaction terms. The interaction strengths (coupling…

hep-th2014

String Perturbation Theory Around Dynamically Shifted Vacuum

Roji Pius, Arnab Rudra, Ashoke Sen

In some string theories, e.g. SO(32) heterotic string theory on Calabi-Yau manifolds, a massless field with a tree level potential can acquire a tachyonic mass at the one loop leve…

hep-th2013

Correlators in the Simplest Gauge-String Duality

Rajesh Gopakumar, Roji Pius

In this note we compare planar correlators such as in the Gaussian matrix model with corresponding genus zero correlators of the A-model topological str…

hep-th2014

Mass Renormalization in String Theory: Special States

Roji Pius, Arnab Rudra, Ashoke Sen

String theory gives a well defined procedure for computing the S-matrix of BPS or a class of massless states, but similar calculation for general massive states is plagued with dif…