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An international research team led by the University of Würzburg and the University of Geneva (UNIGE) is shedding light on one aspect of this mystery: neutrinos are thought to be born in blazars, galactic nuclei fed by supermassive black holes.

Sara Buson has always thought of it as a significant task. In 2017, the researcher and his associates introduced a blazar (TXS 0506+056) as a potential neutrino source for the first time. That study sparked a scientific debate about whether there truly is a connection between blazars and high-energy neutrinos.

After taking this initial, positive step, Prof. Buson’s team received funding from the European Research Council to launch an ambitious multi-messenger research project in June 2021. Analyzing numerous signals (or “messengers,” for example, neutrinos) from the Universe is required. The primary objective is to shed light on the origin of astrophysical neutrinos, potentially confirming blazars as the first highly certain source of high-energy extragalactic neutrinos.

“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.

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.

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.

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.

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.

To understand the team’s findings, we need to talk about neutrinos, the most common and least massive of the massive particles (the particles that have any mass at all). They were first theorized decades ago and only interact through gravity and the “weak force” of the standard model of physics, which means that, like dark matter, neutrinos can just pass through us and our planet and space however they want; they interact with almost nothing. Over the decades, scientists have developed ways to measure neutrinos by tracing their effect on what’s around them.

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.

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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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Generation Ships: Black Hole Ships.
Episode 184, Season 5 E18

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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.