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Life is shaped by choices. The fundamental debate is whether to live life for learning or for pleasure. This weekend, my existential tension boiled down to a simple question: why am I writing my next book and my next scientific paper rather than having fun in the sun?

After some contemplation, I came up with the realization that learning is pleasure. But there is another benefit to writing. Most people will live in the future and I wish to communicate my thoughts to those who will be born long after I am gone. I weigh my priorities in life based on the number of people who might benefit from my actions.

There are currently 8.1 billion people on Earth, about 7% of the total number of humans who have ever lived since the Big Bang, 117 billion. Based on the star count from the Gaia sky survey, the number of stars in the Milky-Way galaxy is comparable to this total value within a factor of a few. This implies that for the foreseeable future, Milky-Way stars could be named after each person who ever lived on Earth.

The first anomaly concerns the speed at which the Universe is expanding. Astronomers determine this in two ways and herein lies the problem: the two methods yield different values.

The obvious method is to observe galaxies (the basic building blocks of the Universe) in the nearby Universe and measure how fast they’re moving away from us. They’re scattering like pieces of cosmic shrapnel in the aftermath of the Big Bang, the titanic explosion in which the Universe was born 13.82 billion years ago.

A team of researchers affiliated with several institutions in Israel has used a Floquet quantum detector to constrain axion-like dark matter, hoping to reduce its parameter space. In their paper published in the journal Science Advances, the group describes their approach to constraining the theoretical dark matter particle as a means to learning more about its properties.

Despite several years of effort by physicists around the world, remains a mystery. Most physicists agree that it exists, but thus far, no one has been able to prove it. One promising theory involving the existence of interacting has begun to lose its luster, and some teams are looking for something else. In this new effort, the researchers seek axions, or axion-like particles. Such dark matter particles have been theorized to be zero-spin and able to possess any number of combinations of mass and interaction strength. The team sought to constrain the features of axion-like particles to reduce the number of possibilities of their existence and thereby increase the chances of proving their existence.

The researchers used a shielded glass cell filled with rubidium-85 and xenon-129 atoms. They fired two lasers at the cell—one to polarize the rubidium atoms’ electronic spin and the xenon’s nuclear spin, and the other to measure spin changes. The experiment was based on the idea that the oscillating field of the axions would impact on the xenon’s spin when they are close in proximity. The researchers then applied a to the cell as a means of blocking the spin of the xenon to within a narrow range of frequencies, allowing them to scan the possible oscillation frequencies that correspond to the range of the axion-like particles. Under this scenario, the Floquet field is theorized to have a frequency roughly equal to the difference between the (NMR) and the electron paramagnetic resonance, and their experiment closes that gap.

Quintessence.


Dive into the cosmic mystery of dark energy with the groundbreaking findings from DESI! Explore how the largest-ever 3D map of the universe challenges our understanding of dark energy and hints at a dynamic cosmos. Discover what this means for the fate of the universe and how it could reshape our view of the cosmos. Join us as we unravel the secrets of the dark universe in this exciting episode!

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Prof Roberto Maiolino, an astrophysicist at the University of Cambridge, and a member of team behind the observations, said: “One problem that we have in cosmology is explaining how these black holes manage to grow so big. In the past we have always talked about gobbling matter very quickly or being born big. Another possibility is that they grow very fast by merging.”

Until now it was not clear whether the merging of galaxies – which is known to have happened – would also result in the black holes at the centres morphing into a single cosmic sinkhole. Recent models have suggested that one of them would be kicked out into space to become a “wandering black hole”

The latest observations use the Webb telescope’s ability to get to the far reaches of the cosmos and so have provided the first glimpse of galactic mergers in the distant past.

New research identifies ONe novae as key sources of phosphorus, essential for life, with peak production aligning with the early Solar System.

Astronomers have proposed a new theory to explain the origin of phosphorus, one of the elements important for life on Earth. The theory suggests a type of stellar explosion known as ONe novae as a major source of phosphorus.

After the Big Bang, almost all of the matter in the Universe was comprised of hydrogen. Other elements were formed later, by nuclear reactions inside stars or when stars exploded in events known as novae or supernovae. But there are a variety of stars and a variety of ways they can explode. Astronomers are still trying to figure out which processes were important in creating the abundances of elements we see in the Universe.

Tiny, fuzzy blobs. I’ve spent a lot of time in the last few years looking at images of tiny, fuzzy blobs. They’re only ever a few pixels wide, like smudges on a photo, but they could be the key that unlocks the mystery of dark matter.

The blobs are galaxies: swirling pools of stars and planets suspended in space, millions of light-years away from Earth. The images were collected by an advanced camera with a 1m (3.3ft) lens mounted on the giant Victor M Blanco Telescope, 2,200m (7,200ft) up in the mountains of the Coquimbo Region of Chile.

Andrea Gallo Rosso, Stockholm University A ghost is haunting our universe. This has been known in astronomy and cosmology for decades. Observations suggest that about 85% of all the matter in the universe is mysterious and invisible. These two qualities are reflected in its name: dark matter. Several experiments have aimed to unveil what it’s made of, but despite decades of searching, scientists have come up short. Now our new experiment, under construction at Yale University in the US, is offering a new tactic.