{"id":536196,"date":"2026-04-17T15:46:10","date_gmt":"2026-04-17T15:46:10","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/536196\/"},"modified":"2026-04-17T15:46:10","modified_gmt":"2026-04-17T15:46:10","slug":"quantum-jamming-explores-the-truly-fundamental-principles-of-nature","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/536196\/","title":{"rendered":"Quantum \u2018Jamming\u2019 Explores the Truly Fundamental Principles of Nature"},"content":{"rendered":"

For the past few decades, researchers have understood that quantum computers should eventually be able to crack the widely used codes<\/a> that secure much of the digital world. To protect against this fate, they\u2019ve spent years developing new codes that appear to be safe from future safecrackers<\/a> armed with quantum computers.<\/p>\n

At the same time, they\u2019ve also devised ingenious ways<\/a> to use the rules of quantum mechanics to keep communications secure. But quantum mechanics, just like the \u201cclassical\u201d mechanics that preceded it, is just a theory of nature. What if it eventually gets superseded by a fuller theory, just as quantum mechanics supplanted Newtonian physics a century ago? Will these quantum communication techniques still be secure in a world where there\u2019s an even more fundamental set of rules?<\/p>\n

\u201cIn terms of these cryptographic protocols, it\u2019s good to be paranoid,\u201d said Ravishankar Ramanathan<\/a>, a quantum information theorist at the University of Hong Kong who works on quantum cryptography. \u201cLet\u2019s try to minimize the assumptions behind the protocol. Let\u2019s suppose that at some future date people realize that quantum mechanics is not the ultimate theory of nature.\u201d<\/p>\n

It\u2019s a possibility worth considering. The difficulty of outstanding problems \u2014 like reconciling quantum mechanics and gravity \u2014 suggests that a post-quantum theory of nature might involve something quite unexpected.<\/p>\n

To guard against the possibility that their protocols are based on faulty assumptions, some quantum cryptographers search for even more basic principles to build upon. Instead of starting from quantum mechanics, they dig deeper, down to the very concept of causality.<\/p>\n

A Subtle Sabotage<\/p>\n

\"\" <\/p>\n

Ravishankar Ramanathan is a quantum information theorist at the University of Hong Kong who works on quantum cryptography.<\/p>\n

Courtesy of Ravishankar Ramanathan<\/p>\n

One way to understand developments in this area is to consider quantum key distribution, which involves taking advantage of the rules of quantum mechanics to pass along a key \u2014 something that can be used to decode a secret message \u2014 in a way that cannot be covertly tampered with. Quantum key distribution makes use of quantum entanglement, which locks two particles together through one of their properties, like spin. Quantum entanglement contains something of a trip wire. If anyone tries to mess with the entanglement \u2014 as they would if they tried to steal the key \u2014 the intrusion will destroy the entanglement, revealing the sabotage. This is because of a fundamental quantum mechanical principle called the \u201cmonogamy of entanglement.\u201d<\/p>\n

But what if this principle no longer held? In such a case, if the people passing the message did not have complete control of their devices, an outsider could potentially subtly change the particles\u2019 entanglement, disrupting the communication without leaving a trace.<\/p>\n

This process is called quantum jamming, and efforts to understand it have surged in recent years.<\/p>\n

For many scientists, jamming is appealing because it can help them better understand both quantum mechanics and the nature of cause and effect. They wonder: Are there deep principles that forbid jamming, that make it impossible? Or, if no principle forbids it, could jamming occur in the real world?<\/p>\n

Jim the Jammer<\/p>\n

Micha\u0142 Eckstein<\/a>, a theoretical physicist at the Jagiellonian University in Krakow, Poland, likes to illustrate jamming with a story. Its protagonists are the classic characters from explanations of quantum mechanics, Alice and Bob.<\/p>\n

Will these quantum communication techniques still be secure in a world where there\u2019s an even more fundamental set of rules?<\/p>\n

\u201cSuppose you have Alice and Bob, and they meet a magician, Jim the Jammer,\u201d Eckstein said. \u201cThe magician says, \u2018I have two balls; one is white, and one is black.\u2019\u201d<\/p>\n

The balls stand in for a pair of entangled particles. If two particles are entangled, they have a property that is linked in some way \u2014 if you measure the first particle and find that its spin is up, for example, the other particle\u2019s spin will inevitably be down, and vice versa. This holds true even if the other particle is halfway across the universe. Here the balls are linked such that if one is white, the other will always be black.<\/p>\n

In the classic trope of stage magic, Jim lets members of the audience see the balls get placed into two boxes, mixed up, and given to Alice and Bob. No one, at this point, knows which ball is in which box.<\/p>\n

Then Alice and Bob get into rocket ships that fly off in opposite directions at close to the speed of light. After a while, Alice opens her box, and Bob opens his. But in the meantime, Jim has performed a trick, and the balls have changed.<\/p>\n

At first, neither Alice nor Bob notices Jim\u2019s interference. Each expects to have a 50% chance of seeing a white or black ball, and when each opens up their box, the ball is either white or black. Nothing Jim does can change that.<\/p>\n

When Alice and Bob meet back on Earth, though, the magician\u2019s trick is revealed. When Alice and Bob compare their measurements, they find that the balls are the same color. Jim has shifted the nature of the balls\u2019 entanglement \u2014 from being opposite colors to being perfect matches.<\/p>\n

That\u2019s the basic idea, though in reality the process of quantum jamming is a little more complicated.<\/p>\n

\"\" <\/p>\n

Mirjam Weilenmann is a researcher at the French national research institute Inria who works on quantum information and the foundations of quantum theory.<\/p>\n

Courtesy of Mirjam Weilenmann<\/p>\n

In the mid-1990s, Jacob Grunhaus, Sandu Popescu, and Daniel Rohrlich were exploring just how far a theory could go beyond the rules of quantum mechanics while still respecting a core principle of Einstein\u2019s: You can\u2019t send information faster than the speed of light. Einstein\u2019s mid-century thought experiments showed that without this \u201cno-signaling\u201d principle, the very notion of cause and effect would start to fray. Since then, the no-signaling principle has become a core assumption when physicists consider what might lie beyond quantum mechanics. \u201cWhen we work in quantum foundations, what we take very seriously is the no-signaling principle,\u201d said Mirjam Weilenmann<\/a> of the French national research institute Inria.<\/p>\n

Grunhaus, Popescu, and Rohrlich imagined jamming<\/a> as a kind of super-entanglement that could interfere with entangled particles. Just as you could use a measuring device to determine the fate of a distant entangled particle, you could use a hypothetical jamming device to change the correlation between a pair of distant entangled particles. If this jamming procedure obeyed a few key rules, some physicists argue, it would secretly disrupt quantum entanglement without disrupting causality.<\/p>\n

The idea of quantum jamming is so strange that initially physicists didn\u2019t know quite what to do with it. \u201cWe wrote that paper and that was the end of it,\u201d Popescu<\/a> said.<\/p>\n

Cause and Effect<\/p>\n

Twenty years later, the time was right to explore it further.<\/p>\n

Quantum cryptography had grown, as quantum computers went from theoretical ideas to experiments in the real world. In the first decade of the 2000s, several<\/a> groups<\/a> developed<\/a> device-independent quantum key distribution, a quantum cryptography procedure that depends on the monogamy of entanglement.<\/p>\n

In 2016, Ramanathan and Pawe\u0142 Horodecki were thinking about these protocols when they found the paper by Grunhaus, Popescu, and Rohrlich. \u201cWe started to realize that this property of monogamy, upon which all of device-independent cryptography is based, completely fails once you start to allow these types of jamming correlations,\u201d Ramanathan said.<\/p>\n

Soon, jamming was the subject of vigorous discussion. Many researchers felt the thought experiment was missing something important: While jamming can\u2019t be used to send signals faster than light, influencing the state of a distant quantum particle still feels like the kind of \u201cspooky action at a distance\u201d that long ago tormented Einstein.<\/p>\n

But for some researchers, the discomfort that quantum jamming creates is inspiring new ideas. \u201cI see it as a tool to try to help hone our intuitions of what the right definition of causation is,\u201d said Roger Colbeck<\/a>, who proposed one of the first protocols for device-independent cryptography in his 2006 doctoral thesis.<\/p>\n

Now at King\u2019s College London, Colbeck is working with V. Vilasini at Inria research center at the University of Grenoble Alpes to classify<\/a> the way cause and effect work in different theories. For them, jamming serves as a useful edge case. They\u2019re seeking another fundamental principle, like the no-signaling principle, that explains which rules jamming breaks.<\/p>\n

The groups of Ramanathan and Horodecki responded to this work, as well as a recent paper<\/a> by Weilenmann, in a preprint<\/a> in December 2025 that they wrote with Eckstein, Tomasz Miller, and Pawe\u0142 Horodecki\u2019s father, Ryszard. Now, the researchers are in conversation, trying to clarify terms, fix misunderstandings, and look for the fundamental principles behind physical theories.<\/p>\n

\u201cThat\u2019s for me the most interesting question,\u201d Eckstein said. \u201cIs there any new physics behind it? Can physics include such phenomena?\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"For the past few decades, researchers have understood that quantum computers should eventually be able to crack the…\n","protected":false},"author":2,"featured_media":536197,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24],"tags":[2302,90,56,54,55],"class_list":{"0":"post-536196","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-physics","9":"tag-science","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/536196","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=536196"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/536196\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/536197"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=536196"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=536196"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=536196"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}