{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T02:24:53Z","timestamp":1777861493850,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T00:00:00Z","timestamp":1777334400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004761","name":"Natural Science Foundation of Hunan Province, China","doi-asserted-by":"crossref","award":["2025JJ60411"],"award-info":[{"award-number":["2025JJ60411"]}],"id":[{"id":"10.13039\/501100004761","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Continuous-variable quantum key distribution has gradually shifted from optical fiber communication to space communication. In free-space quantum communication, the influence of gravity cannot be ignored. In light of the influence of gravity, this study assesses the efficacy of the thermal-state continuous-variable quantum key distribution (QKD) protocol in a non-inertial reference frame. This differs from the conventional scenario in an inertial reference frame, where pure vacuum Gaussian states are employed without consideration of the influence of gravity. This study examines the potential and challenges of quantum key distribution in the presence of gravitational effects. The feasibility of generating the key under the influence of gravity through the lens of quantum state transfer in a non-inertial reference system is also analyzed. It presents a comprehensive mathematical derivation and simulation of the secret key rate for maintaining a positive rate under specific conditions. Furthermore, it presents a detailed implementation plan for thermal-state quantum key distribution in a non-inertial reference frame, particularly in the context of gravity. It offers valuable insights into the performance of quantum communication in unconventional settings.<\/jats:p>","DOI":"10.3390\/e28050501","type":"journal-article","created":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T07:43:51Z","timestamp":1777448631000},"page":"501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Thermal-State Continuous-Variable Quantum Key Distribution Under the Effects of Gravity"],"prefix":"10.3390","volume":"28","author":[{"given":"Li","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Software, Changsha Social Work College, Changsha 410004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiannan","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Computer and Mathematics, Central South University of Forestry and Technology, Changsha 410004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jian","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Computer and Mathematics, Central South University of Forestry and Technology, Changsha 410004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.tcs.2014.05.025","article-title":"Quantum cryptography: Public key distribution and coin tossing","volume":"560","author":"Bennett","year":"2014","journal-title":"Theor. 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