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Thermodynamic Analysis of Classical and Quantum Search Algorithms
Published
Author(s)
Ray A. Perlner, Yi-Kai Liu
Abstract
We analyze the performance of classical and quantum search algorithms from a thermodynamic perspective, focusing on resources such as time, energy, and memory size. We consider two examples that are relevant to post-quantum cryptography: Grover's search algorithm, and the quantum algorithm for collision-finding. Using Bennett's ``Brownian'' model of low-power reversible computation, we show classical algorithms that have the same asymptotic energy consumption as these quantum algorithms. Thus, the quantum advantage in query complexity does not imply a reduction in these thermodynamic resource costs. In addition, we present realistic estimates of the resource costs of quantum and classical search, for near-future computing technologies.
Perlner, R.
and Liu, Y.
(2018),
Thermodynamic Analysis of Classical and Quantum Search Algorithms, Quantum Information Processing (QIP 2018), Delft, -1, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=924493
(Accessed October 10, 2025)