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  • Open Access

Quantum kernels through the lens of entangled tensor kernels

Seongwook Shin1,2,*, Ryan Sweke3,4,5,†, and Hyunseok Jeong6,‡

  • *Contact author: seongwook_shin@sejong.ac.kr
  • †Contact author: rsweke@aims.ac.za
  • ‡Contact author: h.jeong37@gmail.com
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Phys. Rev. Research 8, 023181 – Published 19 May, 2026

DOI: https://doi.org/10.1103/c53t-rybw

Abstract

Quantum kernel methods are one of the most explored approaches to quantum machine learning. However, the structural properties and inductive bias of quantum kernels are not fully understood. In this work, we introduce the notion of entangled tensor kernels—a generalization of product kernels from classical kernel theory—and show that all embedding quantum kernels can be understood as an entangled tensor kernel. We discuss how this perspective allows one to gain insights into both the unique inductive bias of quantum kernels and potential methods for their dequantization.

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Phys. Rev. Research 8, 023181– Published 19 May, 2026
  • Received 29 April 2025
  • Accepted 25 April 2026
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