The Big Bang likely brought our universe into existence. What will mark its grand finale? Scientists blend imagination and data to make predictions.
Category: cosmology
A new quantum radio device may detect axions—potential dark matter particles—marking a breakthrough in the hunt for the universe’s missing 85% mass.
Physicist Richard Lieu first explored the idea that gravity could exist without mass—now he’s got a new cosmological model that eschews the need for dark energy.
Dark matter is a confounding concept that teeters on the leading edges of cosmology and physics. We don’t know what it is or how exactly it fits into our understanding of the universe. We only know that its unseen mass is a critical part of the cosmos.
Astronomers know dark matter exists. They can tell by the way galaxies rotate, by exploiting gravitational lensing, and by analyzing fluctuations in the Cosmic Microwave Background. But new research suggests that there might be another way to detect its presence.
The research is “Dark Matter (S)pins the Planet,” and it’s available on the arXiv preprint server. Haihao Shi, from the Xinjiang Astronomical Observatory at the Chinese Academy of Sciences, is the lead author. The co-authors are all from Chinese research institutions.
Renowned physicist Stephen Hawking passed away earlier this year, but his legacy to science will live on. His final theory on the origin of the universe has now been published, and it offers an interesting departure from earlier ideas about the nature of the “multiverse.”
Ideas about how the universe came to exist the way we see it today have been adapted and built on for decades. The new paper, authored by Hawking and Professor Thomas Hertog, adds to the literature with a new understanding of a theory known as eternal inflation.
After the Big Bang kickstarted the universe, it expanded exponentially for a brief fraction of a fraction of a second. When that inflationary period ended, the universe continued to expand at a much slower rate. But according to the eternal inflation model, quantum fluctuations mean that in some regions of the universe, that rapid inflation never stopped. That results in a gigantic “background” universe full of an infinite number of smaller pocket universes – including the one we live in.
The CMS collaboration at CERN has observed an unexpected feature in data produced by the Large Hadron Collider (LHC), which could point to the existence of the smallest composite particle yet observed. The result, reported at the Rencontres de Moriond conference in the Italian Alps this week, suggests that top quarks – the heaviest and shortest lived of all the elementary particles – can momentarily pair up with their antimatter counterparts to produce an object called toponium. Other explanations cannot be ruled out, however, as the existence of toponium was thought too difficult to verify at the LHC, and the result will need to be further scrutinised by CMS’s sister experiment, ATLAS.
High-energy collisions between protons at the LHC routinely produce top quark–antiquark pairs (tt-bar). Measuring the probability, or cross section, of tt-bar production is both an important test of the Standard Model of particle physics and a powerful way to search for the existence of new particles that are not described by the 50-year-old theory. Many of the open questions in particle physics, such as the nature of dark matter, motivate the search for new particles that may be too heavy to have been produced in experiments so far.
CMS researchers were analysing a large sample of tt-bar production data collected in 2016–2018 to search for new types of Higgs bosons when they spotted something unusual. Additional Higgs-like particles are predicted in many extensions of the Standard Model. If they exist, such particles are expected to interact most strongly with the singularly massive top quark, which weighs in at 184 times the mass of the proton. And if they are massive enough to decay into a top quark–antiquark pair, this should dominate the way they decay inside detectors, with the two massive quarks splintering into “jets” of particles.
A team of astronomers at the Space Telescope Science Institute, working with one colleague from the University of St Andrews’ Center for Exoplanet Science and another from the European Southern Observatory, has confirmed the existence of a lone black hole. In their paper published in The Astrophysical Journal, the group describes how they studied newer data regarding an object they had spotted several years ago to confirm its identity.
In 2022, members of essentially the same team reported the discovery of what they described as a “dark object” moving through the constellation Sagittarius. They suggested it might be a lone black hole. Shortly thereafter, a second research team challenged that result, suggesting it was more likely a neutron star. After continuing to study the object, the original research team has found more evidence backing up their original claim that it is likely a lone black hole.
Prior to this new finding, all the black holes that have been identified have also had a companion star —they are discovered due to their impact on light emitted by their companion star. Without such a companion star, it would be very difficult to see a black hole. The one identified by the team was only noticed because it passed in front of a distant non-companion star, magnifying its light and shifting its position in the sky for a short while.
An evolutionary algorithmic phase transition 2.6 billion years ago may have sparked the emergence of eukaryotic cells
Posted in biological, cosmology, evolution, genetics, information science | Leave a Comment on An evolutionary algorithmic phase transition 2.6 billion years ago may have sparked the emergence of eukaryotic cells
An international collaboration between four scientists from Mainz, Valencia, Madrid, and Zurich has published new research in the Proceedings of the National Academy of Sciences, shedding light on the most significant increase in complexity in the history of life’s evolution on Earth: the origin of the eukaryotic cell.
While the endosymbiotic theory is widely accepted, the billions of years that have passed since the fusion of an archaea and a bacteria have resulted in a lack of evolutionary intermediates in the phylogenetic tree until the emergence of the eukaryotic cell. It is a gap in our knowledge, referred to as the black hole at the heart of biology.
“The new study is a blend of theoretical and observational approaches that quantitatively understands how the genetic architecture of life was transformed to allow such an increase in complexity,” stated Dr. Enrique M. Muro, representative of Johannes Gutenberg University Mainz (JGU) in this project.
The detection of dark matter, the elusive type of matter predicted to make up most of the universe’s mass, is a long-standing goal in the field of astrophysics. As dark matter does not emit, reflect or absorb light, it cannot be observed using conventional experimental methods.
A promising dark matter candidate is so-called ultralight dark matter, which consists of particles with extremely low masses. Astrophysicists have been searching for these ultralight dark matter particles using various approaches and methods, yet they have not yet been detected.
Researchers at the University of Florida recently proposed a new method for the direct detection of ultralight dark matter particles, which is based on astrometry, the precise measurement of the positions and motions of celestial objects.
With its Legacy Survey of Space and Time, the new observatory is expected to build the most precise map of the universe — ever.