The Multiverse fuels some of the 21st century’s best fiction stories. But its supporting pillars are on extremely stable scientific footing.
Category: cosmology – Page 62
After its “birth” in the Big Bang, the universe consisted mainly of hydrogen and a few helium atoms. These are the lightest elements in the periodic table. More-or-less all elements heavier than helium were produced in the 13.8 billion years between the Big Bang and the present day.
Stars have produced many of these heavier elements through the process of nuclear fusion. However, this only makes elements as heavy as iron. The creation of any heavier elements would consume energy instead of releasing it.
In order to explain the presence of these heavier elements today, it’s necessary to find phenomena that can produce them. One type of event that fits the bill is a gamma-ray burst (GRB)—the most powerful class of explosion in the universe. These can erupt with a quintillion (10 followed by 18 zeros) times the luminosity of our sun, and are thought to be caused by several types of event.
A JWST/MIRI spectrum of an early quasar in the mid-infrared indicates that J1120+0641 had a mature feeding structure 760 Myr after the Big Bang. This finding suggests that supermassive black holes and their torii build up surprisingly quickly.
A new theory of quantum gravity, which attempts to unite quantum physics with Einstein’s relativity, could help solve the puzzle of the universe’s expansion, a theoretical paper suggests.
Leonardo DiCaprio’s dream.
Stars at the Milky Way’s center stay young forever, scientists claim, by feeding off dark matter particles that are abundant there.
The detailed calculations demonstrate that black holes of 10 solar masses may comprise at most 1.2% of dark matter, 100 solar mass black holes—3.0% of dark matter, and 1,000 solar mass black holes—11% of dark matter.
“Our observations indicate that primordial black holes cannot comprise a significant fraction of the dark matter, and simultaneously, explain the observed black hole merger rates measured by LIGO and Virgo,” says Prof. Udalski.
Therefore, other explanations are needed for massive black holes detected by LIGO and Virgo. According to one hypothesis, they formed as a product of the evolution of massive, low-metallicity stars. Another possibility involves mergers of less massive objects in dense stellar environments, such as globular clusters.
“At this point, the neutrinos go from passive particles—almost bystanders—to major elements that help drive the collapse,” Savage said. “Supernovae are interesting for a variety of reasons, including as sites that produce heavy elements such as gold and iron. If we can better understand neutrinos and their role in the star’s collapse, then we can better determine and predict the rate of events such as a supernova.”
Scientists seldom observe a supernova close-up, but researchers have used classical supercomputers such as ORNL’s Summit to model aspects of the process. Those tools alone wouldn’t be enough to capture the quantum nature of neutrinos.
“These neutrinos are entangled, which means they’re interacting not just with their surroundings and not just with other neutrinos but with themselves,” Savage said.
An international team of astronomers today announced the discovery of the two earliest and most distant galaxies ever seen, dating back to only 300 million years after the Big Bang. These results, using NASA’s James Webb Space Telescope (JWST), mark a major milestone in the study of the early universe.
The discoveries were made by the JWST Advanced Deep Extragalactic Survey (JADES) team. Daniel Eisenstein from the Center for Astrophysics | Harvard & Smithsonian (CfA) is one of the team leaders of JADES and Principal Investigator of the observing program that revealed these galaxies. Ben Johnson and Phillip Cargile, both Research Scientists at CfA, and Zihao Wu, a Harvard Ph.D. student at CfA, also played important roles.
Because of the expansion of the universe, the light from distant galaxies stretches to longer wavelengths as it travels. This effect is so extreme for these two galaxies that their ultraviolet light is shifted to infrared wavelengths where only JWST can see it. Because light takes time to travel, more distant galaxies are also seen as they were earlier in time.
Squeeze enough stuff into one spot, space-time itself will pucker up in a sweet cosmic kiss known as a black hole.
As far as Einstein’s sums are concerned, that ‘stuff’ includes the massless glow of electromagnetic radiation. Given E = mc2, which describes the equivalence between mass and energy, the energy of light itself should – in theory – be capable of creating a black hole if enough of it is concentrated in one spot.
Before you crack out the big-gun lasers and punch some holes into the Universe’s floorboards, there’s one thing researchers from the Complutense University of Madrid in Spain and the University of Waterloo in Canada want you to know.
What is Dark Energy? A mysterious substance that fills space and causes it to expand is Dark Energy .70% of the universe’s energy is in the form of ‘dark energy’