{"id":99828,"date":"2025-05-14T04:11:07","date_gmt":"2025-05-14T04:11:07","guid":{"rendered":"https:\/\/www.europesays.com\/uk\/99828\/"},"modified":"2025-05-14T04:11:07","modified_gmt":"2025-05-14T04:11:07","slug":"particles-can-be-measured-jointly-without-bringing-them-together-an-advance-for-quantum-communication-and-computing","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/uk\/99828\/","title":{"rendered":"Particles can be measured jointly without bringing them together\u2014an advance for quantum communication and computing"},"content":{"rendered":"<p>            <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.europesays.com\/uk\/wp-content\/uploads\/2025\/05\/remote-particle-measur.jpg\" alt=\"Remote particle measurement via quantum entanglement\" title=\"The first (a) and second (b) level of the finite-consumption version of the Vaidman localization protocol. Credit: Physical Review X (2025). DOI: 10.1103\/PhysRevX.15.021013\" width=\"800\" height=\"530\"\/><\/p>\n<p>                The first (a) and second (b) level of the finite-consumption version of the Vaidman localization protocol. Credit: Physical Review X (2025). DOI: 10.1103\/PhysRevX.15.021013<\/p>\n<p>By breaking away from the laws of classical physics, quantum physics has opened the door to describing the behavior of atoms and particles. This science, which explores the most fundamental building blocks of nature, relies in particular on the ability to measure their individual and collective properties.<\/p>\n<p>But such measurements are notoriously challenging: the instruments used are themselves governed by <a href=\"https:\/\/phys.org\/tags\/quantum+laws\/\" rel=\"tag noopener\" class=\"textTag\" target=\"_blank\">quantum laws<\/a>, and their interaction with particles can alter the very properties they are meant to observe.<\/p>\n<p>&#8220;The field of quantum measurements is still poorly understood because it has received little attention so far. Until now, research has mainly focused on the states of <a href=\"https:\/\/phys.org\/tags\/quantum+systems\/\" rel=\"tag noopener\" class=\"textTag\" target=\"_blank\">quantum systems<\/a> themselves, which feature properties\u2014like entanglement or superposition\u2014that are more directly applicable to areas such as quantum cryptography or <a href=\"https:\/\/phys.org\/tags\/quantum+computing\/\" rel=\"tag noopener\" class=\"textTag\" target=\"_blank\">quantum computing<\/a>,&#8221; explains Alejandro Pozas Kerstjens, Senior Research and Teaching Assistant in the Department of Applied Physics, Physics Section, at the UNIGE Faculty of Science.<\/p>\n<p>Particles linked by an invisible thread<\/p>\n<p>These measurements are essential for the development of future technologies such as quantum communication, which relies on encoding information into, for instance, particles of light (photons). To access this information, the particles must first be measured. A central question is whether it&#8217;s possible to perform a joint measurement on two or more separate particles\u2014each carrying part of the information\u2014without physically bringing them together.<\/p>\n<p>In their new study <a href=\"https:\/\/link.aps.org\/doi\/10.1103\/PhysRevX.15.021013\" target=\"_blank\" rel=\"noopener\">published<\/a> in Physical Review X, the team from the UNIGE Department of Physics composed of Jef Pauwels, Pozas Kerstjens, Flavio Del Santo, and Nicolas Gisin, demonstrates that certain simple yet fundamental measurements can be performed on separate particle systems, as long as the measurement devices share entangled particles.<\/p>\n<p>Entanglement, a cornerstone of <a href=\"https:\/\/phys.org\/tags\/quantum+physics\/\" rel=\"tag noopener\" class=\"textTag\" target=\"_blank\">quantum physics<\/a>, links two or more particles so that the state of one instantly determines the state of the other. Measuring one particle immediately reveals the corresponding property in the other, regardless of the distance between them.<\/p>\n<p>&#8220;However, there&#8217;s a twist: depending on their complexity, some measurements require more\u2014or fewer\u2014entangled <a href=\"https:\/\/phys.org\/tags\/particles\/\" rel=\"tag noopener\" class=\"textTag\" target=\"_blank\">particles<\/a> to be performed properly,&#8221; explains Pozas Kerstjens. To address this, the research team has developed a classification system\u2014a kind of catalog\u2014that maps out different types of measurements and the entanglement resources needed to carry them out.<\/p>\n<p>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\tPromising applications<\/p>\n<p>These results represent a step toward a more systematic understanding of measurements in quantum systems. They could find applications not only in quantum communication but also in quantum computing. For instance, in classical computer simulations, calculations are split across multiple machines, and the results are then brought together.<\/p>\n<p>A similar approach is being considered for quantum computers, but here, reading the results involves performing measurements across several machines.<\/p>\n<p>&#8220;Thanks to our joint remote measurement protocols, it would be possible to eliminate the need for centralization: Each quantum computer would measure its own part, and the overall result could be reconstructed without any physical transfer of data. This is a promising direction that we plan to explore further,&#8221; concludes the researcher.<\/p>\n<p><strong>More information:<\/strong><br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tJef Pauwels et al, Classification of Joint Quantum Measurements Based on Entanglement Cost of Localization, Physical Review X (2025). <a data-doi=\"1\" href=\"https:\/\/dx.doi.org\/10.1103\/PhysRevX.15.021013\" target=\"_blank\" rel=\"noopener\">DOI: 10.1103\/PhysRevX.15.021013<\/a><\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t\t\tProvided by<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/phys.org\/partners\/university-of-geneva\/\" target=\"_blank\" rel=\"noopener\">University of Geneva<\/a><br \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"icon_open\" href=\"http:\/\/www.unige.ch\/\" target=\"_blank\" rel=\"nofollow noopener\"><\/p>\n<p>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t\t<strong>Citation<\/strong>:<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tParticles can be measured jointly without bringing them together\u2014an advance for quantum communication and computing (2025, May 13)<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tretrieved 14 May 2025<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tfrom https:\/\/phys.org\/news\/2025-05-particles-jointly-advance-quantum-communication.html\n\t\t\t\t\t\t\t\t\t\t\t <\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no<br \/>\n\t\t\t\t\t\t\t\t\t\t\t part may be reproduced without the written permission. The content is provided for information purposes only.\n\t\t\t\t\t\t\t\t\t\t\t <\/p>\n","protected":false},"excerpt":{"rendered":"The first (a) and second (b) level of the finite-consumption version of the Vaidman localization protocol. Credit: Physical&hellip;\n","protected":false},"author":2,"featured_media":99829,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3845],"tags":[75,76,74,71,70,72,53,73,16,15],"class_list":{"0":"post-99828","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-materials","9":"tag-nanotech","10":"tag-physics","11":"tag-physics-news","12":"tag-science","13":"tag-science-news","14":"tag-technology","15":"tag-technology-news","16":"tag-uk","17":"tag-united-kingdom"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@uk\/114504235995829398","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/99828","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/comments?post=99828"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/posts\/99828\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media\/99829"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/media?parent=99828"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/categories?post=99828"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/uk\/wp-json\/wp\/v2\/tags?post=99828"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}