Saved in:
Bibliographic Details
Main Authors: Mehta, Vivek, Choudhury, Arghya, Roy, Utpal
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2508.04065
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916883386597376
author Mehta, Vivek
Choudhury, Arghya
Roy, Utpal
author_facet Mehta, Vivek
Choudhury, Arghya
Roy, Utpal
contents Quantum machine learning models are designed for performing learning tasks. Some quantum classifier models are proposed to assign classes of inputs based on fidelity measurements. Quantum Hadamard test is a well-known quantum algorithm for computing these fidelities. However, the basic requirement for deploying the quantum Hadamard test maps input space to L2-normalize vector space. Consequently, computed fidelities correspond to cosine similarities in mapped input space. We propose a quantum Hadamard test with the additional capability to compute the inner product in bounded input space, which refers to the Generalized Quantum Hadamard test. It incorporates not only L2-normalization of input space but also other standardization methods, such as Min-max normalization. This capability is raised due to different quantum feature mapping and unitary evolution of the mapped quantum state. We discuss the quantum circuital implementation of our algorithm and establish this circuit design through numerical simulation. Our circuital architecture is efficient in terms of computational complexities. We show the application of our algorithm by integrating it with two classical machine learning models: Logistic regression binary classifier and Centroid-based binary classifier and solve four classification problems over two public-benchmark datasets and two artificial datasets.
format Preprint
id arxiv_https___arxiv_org_abs_2508_04065
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Generalized Quantum Hadamard Test for Machine Learning
Mehta, Vivek
Choudhury, Arghya
Roy, Utpal
Quantum Physics
Quantum machine learning models are designed for performing learning tasks. Some quantum classifier models are proposed to assign classes of inputs based on fidelity measurements. Quantum Hadamard test is a well-known quantum algorithm for computing these fidelities. However, the basic requirement for deploying the quantum Hadamard test maps input space to L2-normalize vector space. Consequently, computed fidelities correspond to cosine similarities in mapped input space. We propose a quantum Hadamard test with the additional capability to compute the inner product in bounded input space, which refers to the Generalized Quantum Hadamard test. It incorporates not only L2-normalization of input space but also other standardization methods, such as Min-max normalization. This capability is raised due to different quantum feature mapping and unitary evolution of the mapped quantum state. We discuss the quantum circuital implementation of our algorithm and establish this circuit design through numerical simulation. Our circuital architecture is efficient in terms of computational complexities. We show the application of our algorithm by integrating it with two classical machine learning models: Logistic regression binary classifier and Centroid-based binary classifier and solve four classification problems over two public-benchmark datasets and two artificial datasets.
title Generalized Quantum Hadamard Test for Machine Learning
topic Quantum Physics
url https://arxiv.org/abs/2508.04065