AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Graviton boson x3/15/2023 “According to my hypothesis the two theories are mathematically different and cannot be applied simultaneously. In a 2004 review of Brian Greene’s book “The Fabric of the Cosmos” he wrote: Why are my fellow physicists so slow to notice? I make Freeman Dyson responsible for this.ĭyson has popularized the idea that quantum gravity is inaccessible to experiment and thereby discouraged studies of phenomenological consequences of quantum gravity. The arXiv is full with papers on the topic, more than I can keep up with on this blog, and it’s in the popular press more often than I’d like*. I have been organizing and co-organizing a series of conferences on Experimental Search for Quantum Gravity, and in each installment we had to turn away applicants due to space limitations. And that even though hundreds of people work on it. "We are particularly interested in the role played by a scalar particle called radion and on the potential testability at current and future particle colliders.I’ve never met Freeman Dyson, but I’ve argued with him many times.Īlmost every time I give a seminar about my research field, the phenomenology of quantum gravity, I find myself in the bizarre situation of first having to convince the audience that it is a research field. "We now plan to investigate other features of a concrete model in warped extra dimension that we sketch in the article," Cacciapaglia added. Meanwhile, Cacciapaglia and his colleagues plan to build on the theoretical model introduced in their paper, while also evaluating other dark matter candidates. In the future, the results gathered by this team of researchers could inspire new studies and calculations exploring the production of massive gravitons in the universe. "Our results imply that gravitational dark matter is produced 1 picosecond after the Big Bang, at a time when particle physics is well described by the current theories." "This draws a direct connection between the physics studied at the Large Hadron Collider in Geneva and the early Universe physics of gravity and Dark Matter," Cacciapaglia said. Higgs bosons are elementary particles that carry the Higgs field, the field that gives mass to fundamental particles such as electrons and quarks. The calculations performed by Cai, Lee and Cacciapaglia show that instead of being associated with unknown physics occurring shortly after the Big Bang, the production of massive gravitons is most effective below the energy scale in which Higgs bosons reside. "We showed that this enhancement is enough to create the right amount of dark matter in the form of massive gravitons with masses below the MeV." "By computing the production rate of these particles, we discovered that some processes are enhanced below the scale where the Higgs boson generates masses for the ordinary particles, 1 picosecond after the Big Bang," Cacciapaglia said. Cacciapaglia and his colleagues Haiying Cai and Seung Lee wondered whether enough massive gravitons were produced in the early universe for them to be considered a good dark matter candidate. For this reason, the rate at which these particles are produced would be significantly lower than the rate of production of "ordinary" particles. The process through which massive gravitons would theoretically be produced is extremely rare. The points along the red line reproduce the observed Dark Matter in the Universe, while the shaded regions are excluded. Relic density of the massive graviton in the parameter space of the warped model. Their coupling to ordinary matter is very weak, being of gravitational origin." "When gravity propagates in this invisible space, it materializes massive gravitons. "Our study started by looking at extra dimensions, particularly warped extra dimensions, which have been studied a lot in the past 20 years," Giacomo Cacciapaglia, one of the researchers who carried out the study, told. The results of their theoretical calculations were published in a paper in Physical Review Letters. Researchers at Korea University and University of Lyon have recently carried out a theoretical study exploring the possibility that massive gravitons could be good dark matter candidates. While theories predict their existence, these particles have so far never been directly detected. Theory suggests that massive gravitons were produced during collisions between ordinary particles in the hot and dense environment of the early Universe, in the few instants following the Big Bang. Recently, however, some physicists also started investigating the possibility that another type of hypothetical particles, massive gravitons, could be viable dark matter candidates. So far, the most promising dark matter candidates are axions, neutrinos, and weakly interacting massive particles.
0 Comments
Read More
Leave a Reply. |