Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: physics – Page 7

Two scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have discovered a new phase of matter while studying a model system of a magnetic material.

The phase is a never-before-seen pattern of electron spins—the tiny “up” and “down” magnetic moments carried by every electron. It consists of a combination of highly ordered “cold” spins and highly disordered “hot” spins, and it has thus been dubbed “half ice, half fire.” The researchers discovered the new phase while studying a one-dimensional model of a type of magnetic material called a ferrimagnet.

“Half ice, half fire” is notable not only because it has never been observed before, but also because it is able to drive extremely sharp switching between phases in the material at a reasonable, finite temperature. This phenomenon could one day result in applications in the energy and information technology industries.

Read more | >

An international team of researchers used multi-wavelength observations of active galactic nuclei to study how black holes launch relativistic jets. The sixteen sources were observed with the Event Horizon Telescope during its first campaign in 2017. The extreme resolution achieved by the Event Horizon Telescope enabled studies of jets closer than ever to the central supermassive black holes of these galaxies.

The team investigated the acceleration and magnetization of the jets by comparing results obtained at various frequencies and angular scales. The work was led by scientists from the MPIfR in Bonn, Germany, and the IAA-CSIC in Granada, Spain, and is now published in Astronomy & Astrophysics.

To assess the accuracy in understanding the evolution of jets in the centers of active galaxies with supermassive black holes, an international research team led by Jan Röder (MPIfR and IAA-CSIC) compared observations made with the Event Horizon Telescope with previous studies using the Very Long Baseline Array and the Global Millimeter VLBI Array, which probe much larger spatial scales.

Read more | >

Researchers at TU Delft and Brown University have developed scalable nanotechnology-based lightsails that could support future advances in space exploration and experimental physics. Their research, published in Nature Communications, introduces new materials and production methods to create the thinnest large-scale reflectors ever made.

Lightsails are ultra-thin, reflective structures that use laser-driven radiation pressure to propel spacecraft at high speeds. Unlike conventional nanotechnology, which miniaturizes devices in all dimensions, lightsails follow a different approach. They are nanoscale in thickness—about 1/1000th the thickness of a human hair—but can extend to sheets with large dimensions.

Fabricating a as envisioned for the Breakthrough Starshot Initiative would traditionally take 15 years, mainly because it is covered in billions of nanoscale holes. Using advanced techniques, the team, including first author and Ph.D. student Lucas Norder, has reduced this process to a single day.

Read more | >

Does the proton decay? While this was a famous prediction of Grand Unified Theories (GUTS) developed in the 1970s and 1980s, experimentalists have ruled it out—or rather, put lower limits on its mean lifetime of about 1034 years. That’s 20 orders of magnitude greater than the age of the universe.

But two physicists have been wondering: Could the lifetime be different in other places and at other times? Could the proton have decayed faster in the past? Could it decay faster somewhere else in the universe? They have reimagined some physics processes assuming the proton does decay and calculated possible lifetimes of around 1018 years. That’s only eight orders of magnitude beyond the universe’s lifetime. Their work was recently published in Physical Review D.

“People had previously asked various questions of the type, ‘Are the fundamental physics parameters measured on the Earth the same elsewhere in the universe?’” said Peter Denton, a co-author at Brookhaven National Laboratory on Long Island, New York in the U.S. “One case that hadn’t been investigated was the stability of the proton. Earth experiments show that the proton is incredibly stable, but those only apply here, in our part of the galaxy, and now, over the last several decades. What if proton decay depended on time or space?”

Read more | >

When University of Texas at Dallas researchers tested a new surface that they designed to collect and remove condensates rapidly, the results surprised them. The mechanical engineers’ design collected more condensates, or liquid formed by condensation, than they had predicted based on a classic physics model.

The finding revealed a limitation in the existing model and inspired the researchers to develop a new theory to explain the phenomenon, which they outline in an article published online March 13 in the journal Newton.

The theory is critical to the researchers’ work to develop innovative surfaces for applications such as harvesting water from air without electricity.

Read more | >

JILA researchers are pioneering a nuclear clock using thorium-229, which offers unprecedented stability compared to atomic clocks.

By embedding thorium into a solid-state crystal, they have found a nuclear transition largely resistant to temperature changes, crucial for precision timekeeping. Their work could not only redefine timekeeping but also open doors to detecting new physics.

Pushing Beyond Atomic Clocks

Read more | >

Chyba and his team tilted the cylinder precisely at 57 degrees, orienting it perpendicular to both Earth’s magnetic field and its rotational motion. Electrodes attached at each end measured an unmistakable — but minuscule — direct current voltage of about 18 microvolts. Rotate the cylinder 90 degrees, and the voltage vanished. Reverse the cylinder, and the voltage flipped. Control tests with solid cylinders produced no voltage at all. The device was carefully shielded from external interference, such as temperature fluctuations and background electromagnetic noise, to ensure the results were accurate.

“It has a whiff of a perpetual motion machine,” Chyba told Physics Magazine, acknowledging the skepticism his results would inevitably invite. But the physics, he insisted, was sound. The electricity, though tiny, genuinely appeared to flow from Earth’s spin.

The current generated by the device is proportional to its size and the strength of Earth’s magnetic field, which is relatively weak. To produce meaningful amounts of power, the device would need to be much larger or made of materials with even more favorable properties. The researchers speculate that future versions could be miniaturized and connected in series to amplify the voltage, or deployed in space where Earth’s magnetic field is stronger.

Read more | >

This week, ALMA researchers reported the discovery of oxygen in the most distant known galaxy. Geologists believe unusual structures in rock in the desert regions of Namibia, Oman and Saudia Arabia may be evidence of an unknown microorganism. And a group of physicists may have generated a tiny charge of electricity using the Earth’s rotational energy. But the biggest story by far is the second release of data from the DESI survey of the universe, which could upend the standard model:

An emerging generation of cosmological surveys launched this week with the second release of data from the Dark Energy Spectroscopic Instrument at Kitt Peak National Observatory in Arizona, which is mapping an unprecedentedly huge number of galaxies spanning 11 billion years of cosmic history in order to better understand dark energy.

Astronomers have known for many decades that the universe is expanding; in the 1990s, the first image of the cosmic microwave background—the echo of the big bang—revealed that this expansion is accelerating for unknown reasons. Astronomers call this expansion “dark energy,” which translates to “we don’t understand what this energy is.”

Read more | >

Joscha Bach, Cognitive Scientist and AI researcher, as well as Anthony Aguirre, UCSC Professor of Physics, join us to explore the world through the lens of computation and the difficulties we face on the way to beneficial futures.

Topics discussed in this episode include:

-Understanding the universe through digital physics.
–How human consciousness operates and is structured.
–The path to aligned AGI and bottlenecks to beneficial futures.
–Incentive structures and collective coordination.

Find the page for this podcast here: https://futureoflife.org/2021/03/31/j… to be the FLI Podcast Producer here: https://futureoflife.org/job-postings/ Follow the podcast on: Spotify: https://open.spotify.com/show/2Op1WO3… Apple Podcasts: https://podcasts.apple.com/us/podcast… SoundCloud: / futureoflife Have any feedback about the podcast? You can share your thoughts here: www.surveymonkey.com/r/DRBFZCT Timestamps: 0:00 Intro 1:58 What is truth and knowledge? 11:39 What is subjectivity and objectivity? 15:13 What is the universe ultimately? 20:32 Is the universe a cellular automaton? Is the universe ultimately digital or analogue? 25:59 Hilbert’s hotel from the point of view of computation 39:14 Seeing the world as a fractal 43:00 Describing human consciousness 57:46 Meaning, purpose, and harvesting negentropy 1:02:30 The path to aligned AGI 1:05:13 Bottlenecks to beneficial futures and existential security 1:16:01 A future with one, several, or many AGI systems? How do we maintain appropriate incentive structures? 1:30:39 Non-duality and collective coordination 1:34:16 What difficulties are there for an idealist worldview that involves computation? 1:37:19 Which features of mind and consciousness are necessarily coupled and which aren’t? 1:47:47 Joscha’s final thoughts on AGI This podcast is possible because of the support of listeners like you. If you found this conversation to be meaningful or valuable, consider supporting it directly by donating at: https://futureoflife.org/donate Contributions like yours make these conversations possible.

Apply to be the FLI Podcast Producer here: https://futureoflife.org/job-postings/

Follow the podcast on:

Continue reading “Joscha Bach and Anthony Aguirre on Digital Physics and Moving Towards Beneficial Futures” | >

For the first time ever, a very low frequency radio telescope has successfully sent back astronomical data from the lunar surface. Although the mission didn’t quite go as planned, the data has enabled ground-based researchers to confirm the low frequency signature of our own Milky Way Galaxy. A team led by the University of Colorado at Boulder has published their results in The Astrophysical Journal.

We have demonstrated that radio astronomy from the Moon can be done at reasonable costs, and the science potential is high, Jack Burns, a co-author on the paper and a professor emeritus of Astrophysics at the University of Colorado Boulder, tells me via email.

The team used the NASA-funded $2.5 million ROLSES-1 (Radiowave Observations on the Lunar Surface of the photo-Electron Sheath) instrument sent to the Moon as part of Intuitive Machine’s 2024 Odysseus lander. Although Odysseus landed near the ‘Malapert A’ crater, within some 10 degrees of the Moon’s South Pole, it landed badly.

Read more | >