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Archive for the ‘cosmology’ category: Page 14

Jul 17, 2022

Scientists Contemplate Alien Contact (The Daily Galaxy Archive)

Posted by in category: cosmology

“We know now that in the early years of the twentieth century this world was being watched closely by intelligence greater than man’s…across an immense ethereal gulf, minds that to our minds as ours are to the beasts in the jungle, intellects vast, cool and unsympathetic, regarded this earth with envious eyes and slowly and surely drew their plans against us.” So began actor Orson Welles’ chilling Mercury Theater radio performance on October 30, 1938 that Martians were invading, leading terrified listeners to believe that Earth was under attack by hostile aliens.

Welles’ chilling performance was a dramatization of the H.G. Wells science-fiction classic, “The War of the Worlds,” and was part of a weekly series of dramatic broadcasts created in collaboration with the Mercury Theatre on the Air for CBS, according to a transcript of the program.

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Jul 16, 2022

Physicists harness quantum ‘time reversal’ to measure vibrating atoms

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

The quantum vibrations in atoms hold a miniature world of information. If scientists can accurately measure these atomic oscillations, and how they evolve over time, they can hone the precision of atomic clocks as well as quantum sensors, which are systems of atoms whose fluctuations can indicate the presence of dark matter, a passing gravitational wave, or even new, unexpected phenomena.

A major hurdle in the path toward better quantum measurements is noise from the , which can easily overwhelm subtle atomic vibrations, making any changes to those vibrations devilishly hard to detect.

Now, MIT physicists have shown they can significantly amplify quantum changes in atomic vibrations, by putting the particles through two key processes: and time reversal.

Jul 16, 2022

Stephen Hawking’s Final Research Predicts The End Of The Universe And Existence Parallel Universes

Posted by in categories: cosmology, space travel

Two weeks before his death, famed scientist Stephen Hawking published a research article predicting parallel universes and along with the end of our own.

Hawking and co-author Thomas Hertog published their results in “A Smooth Exit from Eternal Inflation,” outlining how scientists may also be able to discover other universes using spaceships. According to Hertog, Hawking completed the work on his deathbed, leaving a legacy worthy of the Nobel Prize.

Jul 13, 2022

Dark Matter’ author says his new book, already being adapted into a film, isn’t just an ‘alarm bell

Posted by in categories: cosmology, genetics

Blake Crouch explores the promise and perils of genetically modified humans in the sci-fi thriller “Upgrade.”

Jul 13, 2022

Mysterious radio “heartbeat” signal detected from distant galaxy

Posted by in categories: cosmology, mapping

Astronomers from MIT report today that they have discovered a mysterious signal with a pattern akin to a heartbeat, emanating from a far-off galaxy that is billions of light-years from Earth. Exactly what the source may be of this regular pulse of radio waves remains a mystery, as it is the first time that such a signal has been recorded.

They have identified the signal as a fast radio burst (FRB), which is typically an intensely strong burst of radio waves of unknown astrophysical origin that lasts only a few milliseconds at most. This new signal, labelled FRB 20191221A, is unusual, because it persists for up to three seconds, which is about 1,000 times longer than the average FRB. Within this time, there are shorter bursts of radio waves that repeat every 0.2 seconds in a clear periodic pattern, similar to that of a beating heart.

Since the first FRB was discovered in 2007, hundreds of similar radio flashes have been detected across the universe, most recently by the Canadian Hydrogen Intensity Mapping Experiment, or CHIME, an interferometric radio telescope that is located at the Dominion Radio Astrophysical Observatory in British Columbia, Canada. CHIME is designed to pick up radio waves emitted by hydrogen in the very earliest stages of the universe, but the telescope is also sensitive to fast radio bursts. Since it began observing the sky in 2018, CHIME has detected hundreds of FRBs emanating from different parts of the sky.

Jul 12, 2022

Physicists May Have Stumbled Upon an Entirely New Elementary Particle

Posted by in categories: cosmology, particle physics

The sterile neutrino, if it truly exists, only answers to gravity.


Physicists are spelunking the complex findings from an experimental particle reactor found a mile below the surface in the mountains of Russia. What they found has the potential to send an earthquake through the bedrock of the standard model of physics itself: the results could confirm a new elementary particle, called a “sterile neutrino,” or demonstrate a need to revise a portion of the standard model.

The research comes from New Mexico’s Los Alamos National Laboratory in collaboration with the Baksan Neutrino Observatory near the Georgia border in far southwestern Russia. The scientists outlined their findings in two new papers published last month in the journals Physical Review Letters and Physical Review C.

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Jul 11, 2022

The ultimate fate of a star shredded by a black hole

Posted by in categories: cosmology, materials

In 2019, astronomers observed the nearest example to date of a star that was shredded, or “spaghettified,” after approaching too close to a massive black hole.

That tidal disruption of a sun-like star by a black hole 1 million times more massive than itself took place 215 million from Earth. Luckily, this was the first such event bright enough that astronomers from the University of California, Berkeley, could study the optical light from the stellar death, specifically the light’s polarization, to learn more about what happened after the star was torn apart.

Their observations on Oct. 8, 2019, suggest that a lot of the star’s material was blown away at high speed—up to 10,000 kilometers per second—and formed a spherical cloud of gas that blocked most of the high-energy emissions produced as the black hole gobbled up the remainder of the star.

Jul 10, 2022

Black Hole Ships

Posted by in categories: cosmology, space travel

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Black Holes are often considered the greatest dangers to spaceships in science fiction, but they may turn out to be the perfect power source for future spaceships.

Check out PBS Spacetime’s episode on Hawking Radiation: https://www.youtube.com/watch?v=qPKj0YnKANw.
Toth’s Black Hole Calculator: https://www.vttoth.com/CMS/physics-notes/311-hawking-radiation-calculator.
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Jul 10, 2022

Dark matter: Our review suggests it’s time to ditch it in favor of a new theory of gravity

Posted by in categories: cosmology, physics

We can model the motions of planets in the Solar System quite accurately using Newton’s laws of physics. But in the early 1970s, scientists noticed that this didn’t work for disk galaxies —stars at their outer edges, far from the gravitational force of all the matter at their center—were moving much faster than Newton’s theory predicted.

This made physicists propose that an invisible substance called “dark ” was providing extra gravitational pull, causing the stars to speed up—a that’s become hugely popular. However, in a recent review my colleagues and I suggest that observations across a vast range of scales are much better explained in an alternative theory of gravity proposed by Israeli physicist Mordehai Milgrom in 1982 called Milgromian dynamics or Mond —requiring no invisible matter.

Mond’s main postulate is that when gravity becomes very weak, as occurs at the edge of galaxies, it starts behaving differently from Newtonian physics. In this way, it is possible to explain why stars, planets and gas in the outskirts of over 150 galaxies rotate faster than expected based on just their visible mass. But Mond doesn’t merely explain such rotation curves, in many cases, it predicts them.

Jul 10, 2022

Large Hadron Collider switches on at highest ever power level to look for dark matter

Posted by in categories: cosmology, physics

Physicists say the third run will collect more data than the previous two combined.

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