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Archive for the ‘cosmology’ category: Page 135

Jan 3, 2021

Astronomers Improve Their Distance Scale for the Universe. Unfortunately, it Doesn’t Resolve the Crisis in Cosmology

Posted by in category: cosmology

Astronomers have made the cosmic distant ladder more accurate, but that has only made the mystery of cosmic expansion even worse.


Measuring the expansion of the universe is hard. For one thing, because the universe is expanding, the scale of your distance measurements affects the scale of the expansion. And since light from distant galaxies takes time to reach us, you can’t measure what the universe is, but rather what it was. Then there is the challenge of the cosmic distance ladder.

The distance ladder stems from the fact that while we have lots of ways to measure cosmic distance, none of them work at all scales. For example, the greatest distances are determined by measuring the apparent brightness of supernovae in distant galaxies. That works great across billions of light-years, but there aren’t enough supernovae in the Milky Way to nearby measure distances. Perhaps the most accurate distance measurement uses parallax, which measures the apparent shift in the position of a star as the Earth orbits the Sun. Parallax is a matter of simple geometry, but it’s only accurate to a couple of thousand light-years.

Continue reading “Astronomers Improve Their Distance Scale for the Universe. Unfortunately, it Doesn’t Resolve the Crisis in Cosmology” »

Dec 30, 2020

China clamps down in hidden hunt for coronavirus origins

Posted by in categories: biotech/medical, cosmology, government

AP Exclusive: The Chinese government is tightly controlling all COVID-19 research under orders from President Xi Jinping, internal documents obtained by The AP show. As a result, China’s search for the origins of the virus has been cloaked in secrecy. In a sign of how sensitive research has become, police stopped scientists and confiscated their samples at a mineshaft where the closest known relative of the COVID-19 virus was found.


MOJIANG, China (AP) — Deep in the lush mountain valleys of southern China lies the entrance to a mine shaft that once harbored bats with the closest known relative of the COVID-19 virus.

The area is of intense scientific interest because it may hold clues to the origins of the coronavirus that has killed more than 1.7 million people worldwide. Yet for scientists and journalists, it has become a black hole of no information because of political sensitivity and secrecy.

Continue reading “China clamps down in hidden hunt for coronavirus origins” »

Dec 29, 2020

All Dark Matter in the Universe Could Be Primordial Black Holes – Formed From the Collapse of Baby Universes Soon After the Big Bang

Posted by in categories: cosmology, physics

The Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) is home to many interdisciplinary projects which benefit from the synergy of a wide range of expertise available at the institute. One such project is the study of black holes that could have formed in the early universe, before stars and galaxies were born.

Such primordial black holes (PBHs) could account for all or part of dark matter, be responsible for some of the observed gravitational waves signals, and seed supermassive black holes found in the center of our Galaxy and other galaxies. They could also play a role in the synthesis of heavy elements when they collide with neutron stars and destroy them, releasing neutron-rich material.

In particular, there is an exciting possibility that the mysterious dark matter, which accounts for most of the matter in the universe, is composed of primordial black holes. The 2020 Nobel Prize in physics was awarded to a theorist, Roger Penrose, and two astronomers, Reinhard Genzel and Andrea Ghez, for their discoveries that confirmed the existence of black holes. Since black holes are known to exist in nature, they make a very appealing candidate for dark matter.

Dec 28, 2020

Searching for invisible axion dark matter with a new multiple-cell cavity haloscope

Posted by in categories: cosmology, particle physics

Over the past few decades, many experimental physicists have been probing the existence of particles called axions, which would result from a specific mechanism that they think could explain the contradiction between theories and experiments describing a fundamental symmetry. This symmetry is associated with a matter-antimatter imbalance in the Universe, reflected in interactions between different particles.

If this mechanism took place in the early Universe, such a particle might have a very small mass and be ‘invisible. Subsequently, researchers proposed that the might also be a promising candidate for dark matter, an elusive, hypothetical type of matter that does not emit, reflect or absorb light.

While dark matter has not yet been experimentally observed, it is believed to make up 85% of universe’s mass. Detecting axions could have important implications for ongoing dark matter experiments, as it could enhance the present understanding of these elusive particles.

Dec 28, 2020

Is Dark Energy Really “Repulsive Gravity”?

Posted by in category: cosmology

Circa 2012 o.o


“Repulsive gravity”—a powerful repulsion between matter and antimatter—could explain the force known as dark energy, a new theory claims.

Dec 28, 2020

Repulsive gravity as an alternative to dark energy (Part 2: In the quantum vacuum)

Posted by in categories: cosmology, particle physics, quantum physics

Circa 2012


(PhysOrg.com) — During the past few years, CERN physicist Dragan Hajdukovic has been investigating what he thinks may be a widely overlooked part of the cosmos: the quantum vacuum. He suggests that the quantum vacuum has a gravitational charge stemming from the gravitational repulsion of virtual particles and antiparticles. Previously, he has theoretically shown that this repulsive gravity can explain several observations, including effects usually attributed to dark matter. Additionally, this additional gravity suggests that we live in a cyclic Universe (with no Big Bang) and may provide insight into the nature of black holes and an estimate of the neutrino mass. In his most recent paper, published in Astrophysics and Space Science, he shows that the quantum vacuum could explain one more observation: the Universe’s accelerating expansion, without the need for dark energy.

“The was predicted theoretically more than 60 years ago,” Hajdukovic told PhysOrg.com. “Today, there is significant experimental evidence that the quantum vacuum exists. I have decided to combine one reality (the quantum vacuum) with one hypothesis (the negative gravitational charge of antiparticles) and to study the consequences. The hypothesis of the gravitational repulsion between matter and antimatter is older than half a century, but before me no one has used it in the combination with the quantum vacuum. … The results are surprising; there is potential to explain [the Universe’s accelerating expansion] in the framework of the quantum vacuum enriched with the gravitational repulsion between matter and antimatter.”

According to Hajdukovic, in the quantum vacuum arises from the gravitational between the positive gravitational charge of matter and the (hypothetical) negative gravitational charge of antimatter. While matter and antimatter are gravitationally self-attractive, they are mutually repulsive. (This part is similar to Massimo Villata’s theory from part 1, in which negatively charged antimatter exists in voids rather than in the quantum vacuum.) Although the quantum vacuum does not contain real matter and antimatter, short-lived and virtual antiparticles could momentarily appear and form pairs, becoming gravitational dipoles.

Dec 26, 2020

Apple’s 2021 chip strategy will create a massively parallel universe

Posted by in categories: cosmology, robotics/AI

Apple’s Macs will soon march into datacenters, equipped with multi-core CPU, GPU, and AI capabilities in tiny, power-efficient form factors.

Dec 25, 2020

A Link Between Wormholes and Quantum Entanglement

Posted by in categories: cosmology, quantum physics

Circa 2013


Is there a connection between quantum mechanics and Einstein’s general theory of relativity?

Dec 24, 2020

The Case for Teleological Evolution

Posted by in categories: cosmology, evolution, mathematics, neuroscience, quantum physics, singularity

The Big Bang might never have existed as many cosmologists start to question the origin of the Universe. The Big Bang is a point in time defined by a mathematical extrapolation. The Big Bang theory tells us that something has to have changed around 13.7 billion years ago. So, there is no “point” where the Big Bang was, it was always an extended volume of space, according to the Eternal Inflation model. In light of Digital Physics, as an alternative view, it must have been the Digital Big Bang with the lowest possible entropy in the Universe — 1 bit of information — a coordinate in the vast information matrix. If you were to ask what happened before the first observer and the first moments after the Big Bang, the answer might surprise you with its straightforwardness: We extrapolate backwards in time and that virtual model becomes “real” in our minds as if we were witnessing the birth of the Universe.

In his theoretical work, Andrew Strominger of Harvard University speculates that the Alpha Point (the Big Bang) and the Omega Point form the so-called ‘Causal Diamond’ of the conscious observer where the Alpha Point has only 1 bit of entropy as opposed to the maximal entropy of some incredibly gigantic amount of bits at the Omega Point. While suggesting that we are part of the conscious Universe and time is holographic in nature, Strominger places the origin of the Universe in the infinite ultra-intelligent future, the Omega Singularity, rather than the Big Bang.

The Universe is not what textbook physics tells us except that we perceive it in this way — our instruments and measurement devices are simply extensions of our senses, after all. Reality is not what it seems. Deep down it’s pure information — waves of potentiality — and consciousness orchestrating it all. The Big Bang theory, drawing a lot of criticism as of late, uses a starting assumption of the “Universe from nothing,” (a proverbial miracle, a ‘quantum fluctuation’ christened by scientists), or the initial Cosmological Singularity. But aside from this highly improbable happenstance, we can just as well operate from a different set of assumptions and place the initial Cosmological Singularity at the Omega Point — the transcendental attractor, the Source, or the omniversal holographic projector of all possible timelines.

Dec 21, 2020

The Kilonova-Chasing Gravitational-Wave Optical Transient Observer is about to be watching the whole sky

Posted by in categories: cosmology, physics

Lately, there has been a flood of interest in gravitational waves. After the first official detection at LIGO / Virgo in 2015, data has been coming in showing how common these once theoretical phenomena actually are. Usually they are caused by unimaginably violent events, such as a merging pair of black holes. Such events also have a tendency to emit another type of phenomena—light. So far, it has been difficult to observe any optical associated with these gravitational-wave emitting events. But a team of researchers hope to change that with the full implementation of the Gravitation-wave Optical Transient Observer (GOTO) telescope.

The GOTO project is designed specifically to find and monitor the parts of the sky that other instruments, such as LIGO, detect from. Its original incarnation, known as the GOTO-4 Prototype, was brought online in 2017. Located in La Palma, in the Canary Islands, this prototype consisted of four “unit telescopes” (UTs) housed in an 18ft clamshell dome. In 2020, this prototype was upgraded to 8 UTs, allowing for a much wider view of the sky.

The wide field of view is necessary for its work detecting gravitational-wave based optical , as directionality of gravitational waves are notoriously difficult to pin down. The wider the field of view of a , the more likely it will be able to detect an event that happens.