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Shedding light on two pieces of the matter-antimatter puzzle

In the early moments following the Big Bang, matter and antimatter should have been created in equal amounts. However, 13.8 billion years later, the Universe is overwhelmingly made of matter, with antimatter nearly absent. This strange imbalance has baffled scientists for decades, hinting that something must have occurred to tilt the balance in favor of matter.

One of the leading theories to explain this disparity is charge–parity (CP) violation, a phenomenon predicted by the Standard Model of particle physics. CP violation refers to a small but measurable difference in how matter and antimatter behave.

However, the Standard Model predicts that the number of CP violations is far too small to account for the vast predominance of matter. So far, CP violation has only been observed in certain particle decays, notably in mesons — particles made of quarks and an antiquark. To truly understand the origins of the matter-antimatter imbalance, scientists need to see CP violation in a broader range of particles, particularly baryons, composed of three quarks.

Spiderweb protocluster captured by Webb shows supermassive black holes can halt star formation

An international research team has used the James Webb Space Telescope (JWST) to observe massive galaxies discovered by the Subaru Telescope in a corner of the early universe known as the Spiderweb protocluster. The JWST results confirm what had been suggested from the Subaru Telescope observations, namely that supermassive black hole activity can truncate the growth of galaxies.

These results appear in the paper “Spider-Webb: JWST Near Infrared Camera resolved galaxy and nuclear activities in the Spiderweb protocluster at z=2.16” in Monthly Notices of the Royal Astronomical Society on December 18, 2024.

The growth and evolution of galaxies is a major theme in modern astronomy. The origin of giant elliptical galaxies is one riddle. These galaxies consist entirely of old stars, so something early in their evolution must have shut off star formation in the progenitors of giant elliptical galaxies. According to one theory, the at the hearts of the galaxies may play a role in determining the star formation.

Black holes keep ‘burping up’ stars they destroyed years earlier, and astronomers don’t know why

A recent study has revealed that nearly half of black holes that consume stars during tidal disruption events (TDEs) later emit remnants of those stars, sometimes years after the initial event. TDEs occur when a star ventures too close to a black hole, where the black hole’s gravitational pull exerts intense tidal forces. This results in the star being stretched and compressed, a process known as spaghettification, which tears the star apart within hours. This destruction is marked by a burst of electromagnetic radiation visible as a bright flash.

As the star is consumed, part of its material is expelled, while the remaining material forms an accretion disk—a thin, rotating structure around the black hole. The accretion disk initially releases material in chaotic bursts, detectable through radio waves, but these emissions typically fade within a few months. Traditionally, astronomers only observed these radio emissions for a short period after the star’s destruction, missing any longer-term activity.

The new study, led by Yvette Cendes, a research associate at the Harvard and Smithsonian Center for Astrophysics, involved monitoring black holes for several years after TDEs. Published on Aug. 25 in the preprint database arXiv, the findings showed that in up to 50% of the cases, black holes expelled material years after consuming a star. In 10 of the 24 studied black holes, this delayed emission occurred between two and six years after the initial star-destroying event. These unexpected “burps” were observed as sudden bursts of radio waves, indicating that the black holes “turned on” again long after the initial event.

NASA’s Roman Space Telescope Ready To Revolutionize Our View of the Cosmos

The Nancy Grace Roman Space Telescope team at NASA has completed the integration of the telescope and its instruments onto the carrier, a significant milestone in the assembly process.

With the Coronagraph Instrument and the Optical Telescope Assembly in place, the Roman telescope is equipped to explore a vast array of astronomical phenomena, including exoplanets and cosmic mysteries like dark energy and dark matter. The Wide Field Instrument, a powerful 300-megapixel infrared camera, will enhance the telescope’s capability to survey the universe extensively. The project is on schedule for a 2026 completion and a 2027 launch.

Integration of roman space telescope components.

The Dark Energy Pushing our Universe Apart may not be what it seems, scientists say

Distant, ancient galaxies are giving scientists more hints that a mysterious force called dark energy may not be what they thought.

Astronomers know that the universe is being pushed apart at an accelerating rate and they have puzzled for decades over what could possibly be speeding everything up. They theorize that a powerful, constant force is at play, one that fits nicely with the main mathematical model that describes how the universe behaves. But they can’t see it and they don’t know where it comes from, so they call it dark energy.

It is so vast it is thought to make up nearly 70% of the universe—while ordinary matter like all the stars and planets and people make up just 5%.

Study claims all observables in nature can be measured with a single constant: The second

A group of Brazilian researchers has presented an innovative proposal to resolve a decades-old debate among theoretical physicists: How many fundamental constants are needed to describe the observable universe? Here, the term “fundamental constants” refers to the basic standards needed to measure everything.

The study is published in the journal Scientific Reports.

The group argues that the number of fundamental constants depends on the type of in which the theories are formulated; and that in a relativistic space-time, this number can be reduced to a single constant, which is used to define the standard of time. The study is an original contribution to the controversy sparked in 2002 by a famous article by Michael Duff, Lev Okun and Gabriele Veneziano published in the Journal of High Energy Physics.

Holography entangles quantum physics with gravity

Second of two parts (read part 1)

If you want to understand gravity, it makes sense to study black holes. Nowhere else can you find so much gravity so conveniently compacted into such a relatively small space.

In a way, in fact, black holes are nothing but gravity. As Einstein showed, gravity is just the warping of spacetime, and black holes are big spacetime sinks. All the matter falling in gets homogenized into nothingness, leaving behind nothing but warped spacetime geometry.

LHCb sheds light on two pieces of the matter–antimatter puzzle: Baryon and beauty hadron decays

In the Big Bang, matter and antimatter should have been created in equal amounts. But fast forward 13.8 billion years to the present day, and the universe is made almost entirely of matter, so something must have happened to create this imbalance.

The Standard Model of particle physics predicts an asymmetry between and antimatter known as charge–parity (CP) violation. But the size of this asymmetry in the Standard Model is not large enough to account for the imbalance and the asymmetry has so far been observed only in certain decays of particles called mesons, which are made of a quark and an antiquark. It remains to be seen in other meson decays and in decays of other types of particles, such as three-quark particles called baryons.

In two new articles posted to the arXiv preprint server, the LHCb collaboration at the Large Hadron Collider (LHC) reports seeing evidence of CP violation in decays of baryons and in decays of beauty hadrons into charmonium particles, shedding light on these two pieces of the matter–antimatter puzzle.

Google’s Quantum Chip Sparks Debate on Multiverse Theory

Google’s latest quantum computer chip, which the team dubbed Willow, has ignited a heated debate in the scientific community over the existence of parallel universes.

Following an eye-opening achievement in computational problem-solving, claims have surfaced that the chip’s success aligns with the theory of a multiverse, a concept that suggests our universe is one of many coexisting in parallel dimensions. In this piece, we’ll examine both sides of this argument that seems to have opened up a parallel universe of its own — with one universe of scientists suggesting the Willow experiments offer evidence of a multiverse and the other suggesting it has nothing to do with the theory at all.

According to Google, Willow solved a computational problem in under five minutes — a task that would have taken the world’s fastest supercomputers approximately 10 septillion years. This staggering feat, announced in a blog post and accompanied by a study in the journal Nature, demonstrates the extraordinary potential of quantum computing to tackle problems once thought unsolvable within a human timeframe.