activity
20242026
collaborators

5 papers

quant-ph2026

Spectral gap of Lee-Yang Hamiltonians

Chaithanya Rayudu, Jun Takahashi

The Lee-Yang theorem and its quantum extensions state that, for a broad class of Hamiltonians on any graph, the partition function's zeros in the complex magnetic field plane lie o…

quant-ph2026

An SU(2)-symmetric Semidefinite Programming Hierarchy for Quantum Max Cut

Jun Takahashi, Chaithanya Rayudu, Cunlu Zhou +3

Understanding and approximating extremal energy states of local Hamiltonians is a central problem in quantum physics and complexity theory. Recent work has focused on developing ap…

quant-ph2025

Fast mixing of operator-loop path-integral quantum Monte Carlo for stoquastic XY Hamiltonians

Chaithanya Rayudu, Jun Takahashi

Quantum Monte Carlo method with operator-loop update is a powerful technique that has been extensively used with great success in condensed matter physics. It enables one to sample…

quant-ph2025

Fermionic Independent Set and Laplacian of an independence complex are QMA-hard

Chaithanya Rayudu

The Independent Set is a well known NP-hard optimization problem. In this work, we define a fermionic generalization of the Independent Set problem and prove that the optimization…

quant-ph2024

Constrained local Hamiltonians: quantum generalizations of Vertex Cover

Ojas Parekh, Chaithanya Rayudu, Kevin Thompson

Recent successes in producing rigorous approximation algorithms for local Hamiltonian problems such as Quantum Max Cut have exploited connections to unconstrained classical discret…