So far, scientists — particularly physicists — have been going about research assuming that the physical world stands on four pillars — the four forces that control the natural world. If you were thinking 'earth, wind, water, fire', have another go.
The forces controlling the world, and by extension, the visible universe, are gravity, electromagnetism, weak nuclear forces, and strong nuclear forces. Research from scientists at the Institute for Nuclear Research at the Hungarian Academy of Sciences (Atomki) could be pointing to another, previously undiscovered "force" in nature. They "watched" an energetic (excited) helium atom release energy by emitting light, before returning to its unexcited state. During this process, the particles seemed to split at an unusual angle in repeated studies — always a 115-degree-angle.
This phenomenon involving helium has no fitting explanation basis the four known forces that govern the natural world.
The output of photon experiments from CERN's 2012 study which proposed a particle that could be the Higgs. Image Courtesy: CERN/CMS
This also isn't the first time scientists have claimed a glimpse of the proposed "fifth force" in action, either. A few years ago, the same research team observed an isotope of beryllium as it decayed, leading them to explore the same with a lighter atom, like Helium. Their findings showed that particles were released by beryllium-8 (radioactive) atoms at a 140-degree angle, which was odd, and new.
"We introduced such a new particle, which nobody saw before, and [whose] existence could not be understood by the widely accepted 'Standard Model' of particle physics, so it faced scrutiny," lead author of the study Attila Krasznahorkay, told CNN in an email.
Simulation of a Higgs boson decaying into four muons at CERN in 1990. Image: Getty/CERN
These old and new observations had something peculiar in common — if the light released by the excited atom is energetic enough, it transforms into an electron and a positron, both of which push away from each other at a predictable angle before zooming off. If the law of energy conservation has taught us anything, it's that the more the light energy released by a pair of particles, the smaller the angle between them should be. There are exceptions in some cases, but largely, that's considered 'normal behaviour' for an excited atom.
Scientists think the force is likely a particle carried by the atoms themselves, which they're calling 'X17'. It is dubbed 'X17' due to its calculated mass of 17 megaelectronvolts, Krasznahorkay told CNN. "X17 could be a particle, which connects our visible world with the dark matter," he said in an email.
The team's 2016 study seemed robust, and drew attention from many researchers world over, who pointed them to the possibility that a whole new particle might be responsible for the anomaly. Nuclear physicists from everywhere have tried to poke holes in the Hungarians' work. So far, they seem to have failed.
A galaxy cluster called Abell S1063 was observed by the NASA/ESA Hubble Space Telescope a few years ago. The huge mass of the cluster — containing both baryonic matter and dark matter — acts as cosmic magnification glass and deforms objects behind it. In the past astronomers used this gravitational lensing effect to calculate the distribution of dark matter in galaxy clusters. A more accurate and faster way, however, is to study the intracluster light (visible in blue), which follows the distribution of dark matter. Image: ESA
"Some very well-known nuclear physicists have done that exercise," Jonathan Feng, a professor of physics and astronomy at the University of California at Irvine who has followed the team's work for years, and believes its research is shaping up to be a gamechanger. In his view, the team is gearing up to win "a no-brainer Nobel Prize" if the results can be replicated.
X17, if confirmed, wouldn't just be any old particle — its characteristics suggested it's a completely new kind of fundamental boson that hasn't been studied before. This would be a fetching discovery because three of the four known forces governing the natural world are known to have carry bosons, which lend their hand in the physics of attraction and repulsion of objects. For instance, the force of gravity is supposedly carried by a hypothetical particle called the graviton, which scientists have predicted but not yet detected.
The 2016 study was snapped up by a respectable journal, Physical Review Letters, while the current study is still awaiting a thorough peer-review process. The findings are pre-published on arXiv, where they're open to scrutiny by others in the field ahead of publication.
The universe is expanding over time and under the influence of gravity, will create a cosmic web of structures like these. The web contains both dark and normal matter. Image: Western Washington University
The invisible pull of dark matter is one of the most aching questions in modern astrophysics, and could fundamentally change the way we see and interact with the universe. Scientists are hoping that a brand new fundamental particle in nature could point to a solution the physics community has been desperately craving. Specifically, a fifth force involving a fundamental "boson" could be connecting the matter we see with the matter we can't (dark matter).
For the time being, X17 is simply a long way from being an "official" particle we can add to existing models of nature and matter. That's for when the team manages to prove beyond any reasonable doubt that their observations are true, which is anywhere from months to years away.
from Firstpost Tech Latest News https://ift.tt/2DrECO8
No comments:
Post a Comment