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Archive for the ‘cosmology’ category: Page 212

Nov 26, 2020

Physicists Pin Down the Nuclear Reaction Just After the Big Bang

Posted by in categories: cosmology, physics

The newly measured rate of a key nuclear fusion process that forged the first atomic nuclei matches the picture of the universe 380,000 years later.

Nov 25, 2020

Physicists Say Universe Filled With Mystery Substance Called “Quintessence”

Posted by in categories: cosmology, physics

Paging Philip Pullman.

Nov 24, 2020

Antimatter gravity could explain Universe’s expansion

Posted by in categories: cosmology, particle physics

O,.o circa 2011 antigravity? Antimatter gravity equals antigravity: D.


(PhysOrg.com) — In 1998, scientists discovered that the Universe is expanding at an accelerating rate. Currently, the most widely accepted explanation for this observation is the presence of an unidentified dark energy, although several other possibilities have been proposed. One of these alternatives is that some kind of repulsive gravity – or antigravity – is pushing the Universe apart. As a new study shows, general relativity predicts that the gravitational interaction between matter and antimatter is mutually repulsive, and could potentially explain the observed expansion of the Universe without the need for dark energy.

Ever since was discovered in 1932, scientists have been investigating whether its gravitational behavior is attractive – like normal matter – or repulsive. Although antimatter particles have the opposite electric charge as their associated matter particles, the masses of antimatter and matter particles are exactly equal. Most importantly, the masses are always positive. For this reason, most physicists think that the gravitational behavior of antimatter should always be attractive, as it is for matter. However, the question of whether the gravitational interaction between matter and antimatter is attractive or repulsive so far has no clear answer.

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Nov 23, 2020

The Sounds of Spacetime

Posted by in categories: cosmology, physics

O,.o this reveals the hertz of the spacetime continuum: 3.


In the biggest events in the universe, massive black holes collide with a chirp and a ring. Physicists are finding ways to listen in.

Nov 23, 2020

This week on The Cosmic Controversy Podcast, I’m pleased to welcome longtime Lowell Observatory astronomer Phil Massey as my guest

Posted by in category: cosmology

An expert on massive stars, Massey has been studying our nearest grand spiral neighbor, the Andromeda Galaxy for decades now. Andromeda is a cornerstone of almost everything we now know about astronomy — from the first recognition that the cosmos is made up of individual galaxies to the discovery of the universe’s still unexplained dark matter. Please join us as we chat about this beautiful and beguiling galactic neighbor.

Nov 21, 2020

Hubble Captures a Black Hole’s ‘Shadow Beams’, Yawning Across Space

Posted by in categories: cosmology, materials

In images from the Hubble Space Telescope, scientists have spotted an entirely new phenomenon. Reaching tens of thousands of light-years into the void of space, vast shadows stretch from the centre of the galaxy IC 5063, as though something is blocking the bright light from therein.

You’ve probably seen something very like it before – bright beams from the Sun when it’s just below the horizon and clouds or mountains only partially block its light, known as crepuscular rays. According to astronomers, the shadows from IC 5063 could be something very similar. They’re just a whole lot bigger – at least 36,000 light-years in each direction.

IC 5063, a galaxy 156 million light-years away, is a Seyfert galaxy. This means it has an active nucleus; the supermassive black hole at its centre is busily guzzling down material from a dense accretion disc and torus of dust and gas around it.

Nov 20, 2020

Galaxies Have Gotten Hotter – A Warming Predicted by Dark Matter Theory

Posted by in category: cosmology

Johns Hopkins University study of 10 billion years of microwaves reveals a warming predicted by dark matter theory.

Who says you can’t get hotter with age?

Researchers from Johns Hopkins University and other institutions have found that, on average, the temperature of galaxy clusters today is 4 million degrees Fahrenheit. That is 10 times hotter than 10 billion years ago, and four times hotter than the Sun’s outermost atmosphere called the corona. The findings are published in the Astrophysical Journal.

Nov 20, 2020

The Physics of COVID-19 –“People are Like Galaxies”

Posted by in categories: biological, cosmology, military, quantum physics

Some of the greatest medical discoveries of the 20th century came from physicists who switched careers and became biologists. Francis Crick, who won the 1962 Nobel Prize in Physiology and helped identify the structure of DNA, started his career as a physicist, as did Leo Szilard who conceived the nuclear chain reaction in 1933, writing the letter for Albert Einstein’s signature that resulted in the Manhattan Project that built the atomic bomb, but spent the last decades of his life doing pioneering work in biology, including the first cloning of a human cell.

Today, a group of world-renowned researchers at the Perimeter Institute for Theoretical Physics with expertise from cosmology to quantum gravity are using physics to help fight the COVID-19 pandemic.

Nov 20, 2020

Episode 25 — Getting To Know Andromeda, Our Grand Spiral Neighbor

Posted by in category: cosmology

This is the episode for anyone who’s interested in learning more about our grand spiral neighbor, the Andromeda Galaxy. Join my guest Lowell Observatory, astronomer Phil Massey as we discuss how our beguiling behemoth of a neighbor helped shape contemporary astronomy.


First cataloged by Al Sufi as a mere optical smudge high in the winter sky, the Andromeda Galaxy has lately been a cornerstone of everything we know about contemporary astronomy and the cosmos as a whole. Join Lowell Observatory astronomer Philip Massey as he outlines how this grand spiral neighbor changed what we know about cosmology. And if you happen to be in the Northern hemisphere, by the end of the episode, you may be ready to try and spot the galaxy with just your naked eyes.

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Nov 19, 2020

Dark Matter Candidate Could Generate String-Like Entities in Exotic Materials

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

Calculations show how theoretical ‘axionic strings’ could create odd behavior if produced in exotic materials in the lab.

A hypothetical particle that could solve one of the biggest puzzles in cosmology just got a little less mysterious. A RIKEN physicist and two colleagues have revealed the mathematical underpinnings that could explain how so-called axions might generate string-like entities that create a strange voltage in lab materials.

Axions were first proposed in the 1970s by physicists studying the theory of quantum chromodynamics, which describes how some elementary particles are held together within the atomic nucleus. The trouble was that this theory predicted some bizarre properties for known particles that are not observed. To fix this, physicists posited a new particle—later dubbed the axion, after a brand of laundry detergent, because it helped clean up a mess in the theory.