{"id":203328,"date":"2025-12-26T21:51:06","date_gmt":"2025-12-26T21:51:06","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/203328\/"},"modified":"2025-12-26T21:51:06","modified_gmt":"2025-12-26T21:51:06","slug":"zombie-stars-might-be-a-beacon-in-our-search-for-dark-matter","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/203328\/","title":{"rendered":"\u2018Zombie Stars\u2019 Might Be a Beacon in Our Search for Dark Matter"},"content":{"rendered":"

As physicist Cumrun Vafa once told me, puzzles in science often come in pairs<\/a>, each serving as the other\u2019s solution. Basically, you never know what concept in physics might end up useful for explaining unexpected phenomena\u2014especially since there\u2019s so much we\u2019ve yet to understand about the universe.<\/p>\n

Astrophysicists from the University of British Columbia in Canada believe that could be the case for axions\u2014a hypothetical particle and a leading candidate for dark matter\u2014in relation to white dwarfs. To be clear, the arXiv<\/a> preprint, which has yet to be peer-reviewed, didn\u2019t find evidence for axions. However, the analysis presents a compelling account of a white dwarf\u2019s death in terms of axion physics, opening exciting opportunities for future research.<\/p>\n

Just a bit of background <\/p>\n

Initially, axions were meant to be a solution to a problem involving an imbalance between matter and antimatter<\/a> in the quantum realm. That was back in 1977, and the idea slowly receded as detection attempts failed to spot the theoretical particle, which was hypothesized to be weakly interacting with other matter and have a low mass.<\/p>\n

Now, consider dark matter. Physicists believe some 85% of the universe consists of dark matter, and there\u2019s ample evidence<\/a> to suggest it exists. True to its name, dark matter is \u201cdark\u201d in the sense that it rarely interacts with anything we can see and is presumably lightweight\u2014similar to axions, if they exist. Given the parallels, physicists have long considered axions to be a good candidate for dark matter. That said, scientists have yet to actually find any real sign of axions\u2014or, for that matter, any dark matter candidate.<\/p>\n

And then there are white dwarfs\u2014the dense, cold, generally inactive stellar cores left over from the death of a star. Technically speaking, at a certain point, these half-dead stars are so dense that they should collapse from too much gravitational pressure.<\/p>\n

But they don\u2019t, thanks to something called electron degeneracy pressure. To put it simply, electrons in the quantum realm can\u2019t share the same energy state. So the electrons spiraling in and out of the star travel faster and faster, eventually generating enough pressure to keep the white dwarf from falling apart.<\/p>\n

A stellar resurrection <\/p>\n

This odd electron movement was what made white dwarfs popular among physicists searching for axions or axion-like particles, according to the study. Specifically, some theoretical models propose that axions could be formed by fast-moving electrons.<\/p>\n

In addition, astrophysical observations had revealed that occasionally, white dwarfs would cool off way faster than expected. If these half-dead stars were actively producing axions, that energy loss would make more sense, the researchers explained in the paper, as axions escaping the star would siphon whatever energy was left over in it.<\/p>\n

To test their hypothesis, the researchers took archival data from the Hubble Space Telescope and ran multiple simulations on how and whether the presence of axions influenced the activity of white dwarfs. The experiments helped them develop several predictions about the temperature and age of a white dwarf, with and without the extra cooling from axions.<\/p>\n

After they completed their experiments, they compared their calculations with actual data from 47 Tucanae, a globular cluster populated by white dwarfs. To their disappointment, however, they found that their model failed to turn up any evidence of axion cooling.<\/p>\n

Okay, but hear me out <\/p>\n

As crazy as this may sound, the researchers concluded that the exercise still found a new limit on the ability for electrons to produce axions: around once every trillion chances. F better or worse, when looking for something as elusive as dark matter, learning what doesn\u2019t work is often what brings scientists closer to what does.<\/p>\n

\u201cThis result doesn\u2019t rule out axions entirely, but it does say it\u2019s unlikely that electrons and axions directly interact with each other,\u201d Paul Sutter, an astrophysicist at Johns Hopkins who wasn\u2019t involved in the study, wrote in a commentary<\/a> for Space.com. \u201cSo, if we\u2019re going to keep searching for axions, we\u2019re going to have to find even more clever ways to look.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"As physicist Cumrun Vafa once told me, puzzles in science often come in pairs, each serving as the…\n","protected":false},"author":2,"featured_media":203329,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[120605,2598,111,139,69,147,392,13760,124461],"class_list":{"0":"post-203328","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-axions","9":"tag-dark-matter","10":"tag-new-zealand","11":"tag-newzealand","12":"tag-nz","13":"tag-science","14":"tag-space","15":"tag-theoretical-physics","16":"tag-white-dwarfs"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/203328","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=203328"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/203328\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/203329"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=203328"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=203328"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=203328"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}