{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T15:26:11Z","timestamp":1771601171116,"version":"3.50.1"},"posted":{"date-parts":[[2026]]},"group-title":"SSRN","reference-count":46,"publisher":"Elsevier BV","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>This paper introduces a transformation that maps discrete quantum registers to real-valued discretetime signals within a digital signal processing framework. The transformation establishes a bijection between unit-norm vectors in a complex Hilbert space and a subspace of real signals constrained by Hermitian symmetry, zero-mean, zero-Nyquist, and unit-energy conditions. Standard DSP operations such as filtering, transformation, and normalization are used to encode quantum registers as real-valued signals. The inverse transformation maps the quantum register from the signal by isolating relevant frequency components and applying an appropriately scaled inverse transform. Injectivity and surjectivity are formally established, ensuring a one-to-one correspondence. This representation enables quantum information to be encoded, analyzed, and manipulated using classical DSP methods, supporting hybrid quantum-classical systems for simulation and communication on conventional hardware.<\/jats:p>","DOI":"10.2139\/ssrn.6275395","type":"posted-content","created":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T14:41:37Z","timestamp":1771598497000},"source":"Crossref","is-referenced-by-count":0,"title":["On Qubits as Discrete Signals"],"prefix":"10.2139","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4487-5362","authenticated-orcid":true,"given":"Francisco","family":"Neves","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0846-0485","authenticated-orcid":true,"given":"Raul","family":"Rato","sequence":"additional","affiliation":[]}],"member":"78","reference":[{"key":"ref1","author":"M A Nielsen","year":"2010","journal-title":"Quantum Computation and Quantum Information, 10th 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