Neutron Lifetime Puzzle: New Solution & ‘Dark Atoms
- A novel theoretical study suggests the existence of a second type of hydrogen atom, one that doesn't interact with light.
- The neutron lifetime puzzle stems from conflicting results obtained by two experimental methods used to measure the average lifespan of free neutrons before they decay into protons, electrons,...
- Eugene Oks, a physicist at Auburn University and author of the study published in Nuclear Physics B, explained the discrepancy.
Unraveling the cosmos: A groundbreaking theory posits the existence of “invisible” hydrogen, offering a potential solution to the enduring neutron lifetime puzzle. This innovative concept suggests that a hidden form of hydrogen, undetectable by conventional means, could account for the discrepancies in neutron decay measurements and, remarkably, explain the nature of dark matter. The study proposes that neutrons might sometimes decay into this invisible hydrogen, thus evading detection in certain experiments. Furthermore, this second flavour of hydrogen may be a key component of dark matter, according to the researcher, Eugene Oks. Experts at News Directory 3 are following developments.Discover the groundbreaking implications of this discovery and how it could reshape our comprehension of the universe’s fundamental elements. Learn which research groups are currently testing the neutron lifetime theory. What’s next for this exciting area of examination?
Invisible Hydrogen Atoms May Solve Dark Matter Mystery
Updated May 31, 2025
A novel theoretical study suggests the existence of a second type of hydrogen atom, one that doesn’t interact with light. this “invisible” hydrogen, researchers propose, could account for a significant portion of the universe’s missing dark matter and resolve a long-standing enigma in particle physics: the neutron lifetime puzzle.
The neutron lifetime puzzle stems from conflicting results obtained by two experimental methods used to measure the average lifespan of free neutrons before they decay into protons, electrons, and neutrinos.
Eugene Oks, a physicist at Auburn University and author of the study published in Nuclear Physics B, explained the discrepancy. “There were two kinds of experiments for measuring the neutron lifetime: beam and bottle.”
Beam experiments count protons produced after neutron decay, while bottle experiments trap ultracold neutrons and count those remaining after a set period. the results from these methods differ by approximately 10 seconds, with beam experiments yielding a neutron lifetime of 888 seconds and bottle experiments reporting 878 seconds. This variance exceeds experimental uncertainty.
Oks proposes that the discrepancy arises as neutrons sometimes decay into a hydrogen atom and a neutrino, rather of the expected three particles. Because the hydrogen atom is electrically neutral,it could pass through detectors undetected,skewing results.
While this two-body decay mode has been theorized before, it was considered extremely rare. Oks argues that previous calculations underestimated the rate because they didn’t account for the possibility of a second, light-insensitive flavor of hydrogen.
“They do not emit or absorb electromagnetic radiation, they remain dark,” Oks said, making them undetectable by conventional instruments.
This second flavor of hydrogen features an electron much closer to the proton then in ordinary hydrogen, rendering it immune to electromagnetic forces. Oks’s calculations suggest that considering this second flavor could increase the rate of two-body decays by a factor of 3,000, perhaps explaining the gap between beam and bottle experiments.
Furthermore, these invisible hydrogen atoms could be a key component of dark matter.A 2020 study by oks indicated that if these atoms were abundant in the early universe, they could explain anomalies in ancient hydrogen radio signals. He suggests they may be the dominant form of baryonic dark matter.
“The status of the second flavor of hydrogen atoms as baryonic dark matter is favored by the Occam’s razor principle,” oks said, noting that this description aligns with the Standard Model of particle physics without requiring new particles.
Oks is collaborating with experimentalists at Los Alamos National Laboratory and Forschungszentrum Jülich in Germany to test his theory. These experiments aim to excite both flavors of hydrogen with an electron beam and then selectively remove ordinary hydrogen atoms, leaving only the invisible ones.
“If prosperous, the experiment could yield results this year,” Oks said. “The success would be a very significant breakthrough both in particle physics and in dark matter research.”
Should the existence of a second hydrogen flavor be confirmed, it could also reshape our understanding of the universe’s early evolution. The precise neutron lifetime is crucial for calculating the abundance of light elements formed in the universe’s first minutes.
What’s next
Future research will explore whether other atomic systems also exhibit two flavors, potentially leading to further discoveries and a more complete picture of cosmic history.