The universe was filled with equal amounts of matter and antimatter in the early days of its existence. The universe cooled as space became larger. The universe is full of stars andgalaxes. What happened to the antimatter and how did it come to dominate the universe? Scientists still don't understand the origin of matter.
The "cosmological collider" has opened a new pathway for probing the origin of matter.
Not all colliders.
High energy colliders can produce very heavy particles that can reveal new physics. The explanation of dark matter and the origin of matter requires much higher energy than a human-made collider can give. The early universe could have been a super-collider.
Cosmic inflation, an era when the universe expanded at an incredibly fast rate, preceded the Big bang, according to an associate professor of physics.
Cui said thatmic inflation enabled the production of heavy new particles and their interactions. The energy of the inflationary universe was 10 billion times larger than that of a human made collider.
As the universe expanded, the tiny structures created by inflation got stretched, resulting in different densities in the universe. The distribution of galaxies across the sky is a result of the seeding of the large-scale structure of our universe. Cui said that new particle physics may be revealed by studying the imprint of the collider in the Cosmic Microwave Background.
Cui and Zhong-Zhi Xianyu, an assistant professor of physics at Tsinghua University, report in the journal Physical Review Letters that they used the physics of the cosmological collider to measure the structure of our universe.
The fact that our current-day universe is dominated by matter is one of the most puzzling mysteries in modern physics. The framework of fundamental physics does not allow for a subtle balance between matter and antimatter in the early universe.
The rescue is due to leptinogenesis.
The origin of the baryon, visible gas and stars, is explained by a well-known mechanism. If the universe began with equal amounts of matter and antimatter, they would have died out. Asymmetrical explanation is needed since matter far exceeds antimatter.
"Leptogenesis is one of the most compelling mechanisms generating the matter," Cui said. There's a new fundamental particle involved. It was thought that testing leptogenesis was impossible because the mass of the right-handed neutrino is so high.
The new work proposes to test leptogenesis by decoding the statistical properties of the spatial distribution of objects. The researchers argue that the cosmological collider effect allows the production of the super- heavy right-handed neutrino.
The astrophysical observations anticipated in the future can potentially detect such signals.
More information: Yanou Cui et al, Probing Leptogenesis with the Cosmological Collider, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.111301 Journal information: Physical Review Letters
All Rights Reserved © 2024
