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arXiv · 2510.02015

Understanding Quantum Imaginary Time Evolution and its Variational form

Andreu Anglés-Castillo·Luca Ion·Tanmoy Pandit·Rafael Gomez-Lurbe·Rodrigo Martínez·Miguel Angel Garcia-March
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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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Andreu Anglés-Castillo, Luca Ion, Tanmoy Pandit, Rafael Gomez-Lurbe, Rodrigo Martínez, Miguel Angel Garcia-March. 2025-10-02. Understanding Quantum Imaginary Time Evolution and its Variational form. https://arxiv.org/abs/2510.02015

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