Understanding Quantum Imaginary Time Evolution and its Variational form

• URL: http://arxiv.org/abs/2510.02015v2
• Date: Fri, 03 Oct 2025 11:11:07 GMT
• Title: Understanding Quantum Imaginary Time Evolution and its Variational form
• Authors: Andreu Anglés-Castillo, Luca Ion, Tanmoy Pandit, Rafael Gomez-Lurbe, Rodrigo Martínez, Miguel Angel Garcia-March,
• Abstract summary: Many computationally hard problems can be encoded in quantum Hamiltonians.<n>The solution to these problems is given by the ground states of these Hamiltonians.<n>A state-of-the-art algorithm for finding the ground state of a Hamiltonian is the so-called Quantum Imaginary Time Evolution.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Many computationally hard problems can be encoded in quantum Hamiltonians. The solution to these problems is given by the ground states of these Hamiltonians. A state-of-the-art algorithm for finding the ground state of a Hamiltonian is the so-called Quantum Imaginary Time Evolution (QITE) which approximates imaginary time evolution by a unitary evolution that can be implemented in quantum hardware. In this paper, we review the original algorithm together with a comprehensive computer program, as well as, the variational version of it.

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