BLOGS

I would like to announce that I have a new short story on my website titled "The Black Cross".It’s a detective yarn set in San Diego in 1940, with the protagonist (left) being a private eye who is called on to recover a black stone cross from Central Africa that he believes has been stolen by Chinese-American gangsters. But little does he know the true origin or significance of the cross, or what his adversaries really plan to do with it…

As for the woman on the right side of the composition, she is connected to the cross in a very important way.

You can read the story for yourself here on my website's blog:

The Black Cross

Artist's representation of the circular phonons. (Courtesy: Nadja Haji and Peter Baum, University Konstanz)

Topics: Applied Physics, Lasers, Magnetism, Materials Science, Phonons

When a magnetic material is bombarded with short pulses of laser light, it loses its magnetism within femtoseconds (10^–15 seconds). The spin, or angular momentum, of the electrons in the material, thus disappears almost instantly. Yet all that angular momentum cannot simply be lost. It must be conserved – somewhere.

Thanks to new ultrafast electron diffraction experiments, researchers at the University of Konstanz in Germany have now found that this “lost” angular momentum is in fact transferred from the electrons to vibrations of the material’s crystal lattice within a few hundred femtoseconds. The finding could have important implications for magnetic data storage and for developments in spintronics, a technology that exploits electron spins to process information without using much power.

In a ferromagnetic material, magnetism occurs because the magnetic moments of the material’s constituent atoms align parallel to each other. The atoms and their electrons then act as elementary electromagnets, and the magnetic fields are produced mainly by the spin of the electrons.

Because an ultrashort laser pulse can rapidly destroy this alignment, some scientists have proposed using such pulses as an off switch for magnetization, thereby enabling ultra-rapid data processing at frequencies approaching those of light. Understanding this ultrafast demagnetization process is thus crucial for developing such applications as well as for better understanding the foundations of magnetism.

Researchers find ‘lost’ angular momentum, Isabelle Dumé, Physics World

A radical reimagining of information processing could greatly reduce the energy use—as well as greenhouse gas emissions and waste heat—from computers. Credit: vchal/Getty Images

Topics: Climate Change, Computer Science, Electrical Engineering, Global Warming, Semiconductor Technology, Thermodynamics

In case you had not noticed, computers are hot—literally. A laptop can pump out thigh-baking heat, while data centers consume an estimated 200 terawatt-hours each year—comparable to the energy consumption of some medium-sized countries. The carbon footprint of information and communication technologies as a whole is close to that of fuel used in the aviation industry. And as computer circuitry gets ever smaller and more densely packed, it becomes more prone to melting from the energy it dissipates as heat.

Now physicist James Crutchfield of the University of California, Davis, and his graduate student Kyle Ray have proposed a new way to carry out computation that would dissipate only a small fraction of the heat produced by conventional circuits. In fact, their approach, described in a recent preprint paper, could bring heat dissipation below even the theoretical minimum that the laws of physics impose on today’s computers. That could greatly reduce the energy needed to both perform computations and keep circuitry cool. And it could all be done, the researchers say, using microelectronic devices that already exist.

In 1961 physicist Rolf Landauer of IBM’s Thomas J. Watson Research Center in Yorktown Heights, N.Y., showed that conventional computing incurs an unavoidable cost in energy dissipation—basically, in the generation of heat and entropy. That is because a conventional computer has to sometimes erase bits of information in its memory circuits in order to make space for more. Each time a single bit (with the value 1 or 0) is reset, a certain minimum amount of energy is dissipated—which Ray and Crutchfield have christened “the Landauer.” Its value depends on ambient temperature: in your living room, one Landauer would be around 10–21 joule. (For comparison, a lit candle emits on the order of 10 joules of energy per second.)

‘Momentum Computing’ Pushes Technology’s Thermodynamic Limits, Phillip Ball, Scientific American

Topics: Civilization, International Space Station, Politics, Space Exploration

ALMATY, March 30 (Reuters) - A U.S. astronaut and two Russian cosmonauts safely landed in Kazakhstan on Wednesday after leaving the International Space Station aboard the same capsule despite heightened antagonism between Moscow and Washington over the conflict in Ukraine.

The flight -- carrying NASA's Mark Vande Hei and Russians Anton Shkaplerov and Pyotr Dubrov back to Earth -- had been closely watched to determine whether escalating strife had spilled over into longtime cooperation in space between the two former Cold War adversaries.

Russian space agency Roscosmos broadcast footage of the landing from the Kazakh steppe and said a group of technical and medical specialists had been dispatched to help the astronauts out of the capsule.

"The crew is feeling good after landing, according to rescuers," Roscosmos chief Dmitry Rogozin wrote on Telegram messenger.

Vande Hei, who had completed his second ISS mission, logged a U.S. space-endurance record of 355 consecutive days in orbit, surpassing the previous 340-day record set by astronaut Scott Kelly in 2016, according to NASA.

U.S. astronaut, two Russian cosmonauts return home from ISS, Olzhas Auyezov and Steve Gorman, Reuters

An activist holds a candle during a vigil in Lafayette Park for nurses who died during the COVID-19 pandemic on January 13, 2022, in Washington, D.C. Credit: Brendan Smialowski/AFP/Getty Images

Topics: Civics, COVID-19, Epidemiology, Existentialism, Politics

With all due respect to the recently departed former Secretary of State Madeline Albright, she started using the phrase "indispensable nation" after political reporter Sydney Blumenthal coined it. From Foreign Policy Magazine:

In his memoir of the Clinton presidency, The Clinton Wars, Blumenthal elaborated on what the phrase was intended to represent: “Only the United States had the power to guarantee global security: without our presence or support, multilateral endeavors would fail.” Albright, then secretary of state, began using the phrase often, and most prominently in February 1998, while defending the policy of coercive diplomacy against Iraq over its limited cooperation with U.N. weapons inspectors when, during an interview on the “Today Show,” she said: “If we have to use force, it is because we are America; we are the indispensable nation. We stand tall and we see further than other countries into the future, and we see the danger here to all of us.”

The Myth of the Indispensable Nation, Micah Zenko, Foreign Policy

Though politically expedient, and in the parlance of activism, it "chants" well, we're not indispensable, nor are we exceptional. We allowed the worst of a pandemic to spread by ineptitude and Twitter addiction, science denialism, and conspiracy theory. Since the introduction of cable news and siloes of news consumption, we have citizens that believe in different versions of reality. It puts the "United States" in the realm of the oxymoron.

Now, we're at this grim milestone. Conservatives live to push buttons, "own the libs," grift off culture issues, and keep their constituents at high levels of anxiety and anger with right-wing echo chambers to ensure they vote for them to "own the libs." Progressives think high-minded logic, social media presence, "woke-ness," diversity, equity, and inclusion by proximity will produce a Star Trek utopia, because of high-minded logic. I purposely made each perspective a grammatical ouroboros. We're at a grim milestone because our major political parties have wholly different means of evaluating reality, and because compromise is frowned upon: "DINO, RINO." There are dark, nefarious forces that only the well-connected to Q-drops or Alex Jones can decipher.

431,000 non-farm jobs were added, and the unemployment rate fell to 3.6%. Yet, the 46th president's approval numbers are in the toilet largely because he isn't as entertaining as the last spastic, pathologically lying, hand-waving caricature of a mob boss with a dead ferret toupee, a metaphor for a lifetime of hiding hard truths from himself.

We are codependent on being perpetually angry, and not wed to the idea of speaking to our neighbors who might not consume the same media. We thus base our understanding of the world and facts on separate lenses we view reality through.

Tom Nichols, former professor at Annapolis Naval Academy, opined about "The Death of Expertise: The Campaign Against Established Knowledge and Why It Matters" in 2017, and it doesn't look like we've turned a corner from that analysis of our national death spiral. Because we can "Google it," we're a Dunning-Kruger nation of narcissists and debase people who put a lot of work into understanding how the world works. We are a byword and a proverb. We are Guy Debord's "Society of the Spectacle."

“The whole idea of a democratic application of skepticism is that everyone should have the essential tools to effectively and constructively evaluate claims to knowledge.”

― Carl Sagan, The Demon-Haunted World: Science as a Candle in the Dark, Good Reads

*****

Laura Jackson feels the loss of her husband Charlie like she is missing a part of herself. He died of COVID early in the pandemic, on May 17, 2020, just weeks after the couple celebrated his 50th birthday. Charlie was an Army veteran who served in Iraq during Desert Storm, and Laura finds herself returning to images of war and loss—to those who have lost a limb but still feel its phantom tingle, who unthinkingly reach for a glass of water or try to step out of bed before realizing what has been lost forever. Even now she still turns to find Charlie, eager to share a joy or a disappointment, only to remember with a jolt that there is a missing space where he once was.

“I don’t know that you ever get over it,” says Jackson, who lives in Charlotte, N.C. “Your person who was supposed to be there for life—to have that tragically ripped away has been a huge, huge adjustment to make.”

The U.S. will record one million confirmed deaths from COVID in the next several weeks. This toll is likely an undercount because there are more than 200,000 other excess deaths that go beyond typical mortality rates, caused in part by the lingering effects of the disease and the strain of the pandemic. These immense losses are shaping our country—how we live, work, and love, how we play and pray and learn and grow.

“We will see the rippling effects of the pandemic on our society and the way it impacts individuals for generations,” says Nyesha Black, director of demographic research at the University of Alabama. “This is definitely a huge marker in the way we will think about society moving forward—it will be that anchor event.” COVID has become the third leading cause of death in the U.S., after heart disease and cancer.

These deaths have wide-ranging consequences. The effects on children may be the longest-lasting. In the U.S., an estimated 243,000 children have lost a caregiver to COVID—including 194,000 who lost one or both parents—and the psychological and economic aftershocks can have lifetime negative impacts on their education and career.

What One Million COVID Dead Mean for the U.S.’s Future, Melody Schreiber, Scientific American

Plastic fantastic: this perovskite-based device can be reconfigured and could play an important role in artificial intelligence systems. (Courtesy: Purdue University/Rebecca McElhoe)

Topics: Artificial Intelligence, Biology, Computer Science, Materials Science

Researchers in the US have developed a perovskite-based device that could be used to create a high-plasticity architecture for artificial intelligence. The team, led by Shriram Ramanathan at Purdue University, has shown that the material’s electronic properties can be easily reconfigured, allowing the devices to function like artificial neurons and other components. Their results could lead to more flexible artificial-intelligence hardware that could learn much like the brain.

Artificial intelligence systems can be trained to perform a task such as voice recognition using real-world data. Today this is usually done in software, which can adapt when additional training data are provided. However, machine learning systems that are based on hardware are much more efficient and researchers have already created electronic circuits that behave like artificial neurons and synapses.

However, unlike the circuits in our brains, these electronics are not able to reconfigure themselves when presented with new training information. What is needed is a system with high plasticity, which can alter its architecture to respond efficiently to new information.

Device can transform into four components for artificial intelligence systems, Sam Jarman, Physics World

ABYSSINIA MEDIA GROUP® will be participating in the

BLACK NERDS EXPO VIRTUAL CONVENTION

being held on FEBRUARY 26, 2022 from 11:00 AM until 5:00 PM PST.

For more information hit this link to: BLACKNERDSEXPO.COM


AMG will be a featured VIRTUAL STORE /EXHIBITOR

at this ONLINE BLACK NERD HISTORICAL EVENT!

The nice part is it’s ALL FREEEEEE!

ABYSSINIA MEDIA GROUP® will ALSO be participating in the

BLACK NERDS EXPO VIRTUAL FILM VIDEO, & ANIMATION CONTEST!

Above is the FLYER calling for more entries with a deadline on the DAY OF SHOW

held on FEBRUARY 26, 2022 DEALINE is 10:00 AM that day PST.

For more information hit this link to: BLACKNERDSEXPO.COM

ALSO featured at the BLACK NERDS EXPO,

A VIRTUAL SHORT WRITING CONTEST!

Below is the FLYER calling for more entries with a

DEADLINE on the DAY OF SHOW held on FEBRUARY 26, 2022 AT 12:00 PM.

For more information hit this link to: 

BLACKNERDSEXPO.COM

What would the BLACK NERDS VIRTUAL EXPO

be without a FREE ONLINE VIRTUAL COSPLAY CONTEST!

Above is the FLYER calling for more entries with a DEADLINE

on the DAY OF SHOW held on FEBRUARY 26, 2022 before 2:00 PM.

For more information hit this link to:

BLACKNERDSEXPO.COM

At CERN in 1973, John Bell (left), who was working there at the time, interacts with Martinus Veltman (right), who was then a professor at Utrecht University in the Netherlands. Since early 2020, COVID-19 has hindered physicists’ ability to travel and discuss physics in person. (Courtesy of CERN.)

Topics: COVID-19, Existentialism, Physics, Research

An excerpt. The longer article piece is at the link following.

The COVID-19 pandemic has not only killed a large number of people—approximately 5.5 million worldwide at the time Physics Today went to press in mid-January—it has also disrupted life in a fundamental, nonperturbative manner, forcing large-scale changes in human behavior from without.

It was difficult at the beginning of 2020 to anticipate the great COVID-19 calamity awaiting the world. In February of that year, I was apparently among the first people to have urged the leadership of the American Physical Society to cancel its upcoming March Meeting in Denver, which APS finally did at the last moment after considerable hesitancy.

The logistics of canceling a meeting of 10 000 people right before the event are not trivial. But given the crowd density in APS March Meetings, it is reasonable to assume that the 2020 event would have led to a few thousand COVID-19 cases just among the physicist attendees. Overall, it may have led to many tens of thousands, perhaps even hundreds of thousands, of cases, if not more. That estimate is based on research related to the now-infamous Boston Biogen superspreader conference in late February 2020. Within a month, roughly 100 people in Massachusetts who either went to the conference or were a household contact of someone who went tested positive. The genetic-code-based investigation estimated that the event led to 300 000 COVID-19 cases worldwide by the beginning of the following November. APS made the right call in canceling the meeting.

Commentary: A physicist’s perspective on COVID-19, Sankar Das Sarma, Physics Today

For anyone with a love of comics, graphic novels and webcomics produced by Black, African American and African artists, writers and illustrators, the Encyclopedia of Black Comics by Sheena C. Howard is an amazing trove of knowledge and insight. The information is thorough, well written and packed with history of where and when Black artists and writers began making comics, many times without acknowledgement of the publishing community.

              With names familiar and unfamiliar, the Encyclopedia of Black Comics list entries alphabetically by last name, along with birth and death dates, colleges and universities attended, what their talents are/were and their comics and titles.

              Examples of entries are: Dawud Anyabwile, co-creator of Brotherman: Dictator of Discipline; Jabaar L. Brown, founder of Underground Comixxx; Mat Johnson, author of Incognegro; Ajuan Mance, author of 1001 Black Men; and Jackie Ormes, "creator of Torchy Brown, and the first published female African American cartoonist."

              Whether you love comics, graphic novels and webcomics, have an interest in them or even just a curiosity, the Encyclopedia of Black Comics will satisfy your level of interest and more. The graphics and illustrations don’t disappoint either.

I represent the Gyeongsang National University SLE department. We are hosting an English film festival and we'd like to run your short films. If you've got any films that didn't make the cut at Cannes or something, send them our way. Free entry. Swing by https://tinyurl.com/gnujeff for submission details. Deadline is tomorrow!

I am happy to announce that I have a new short story posted on my official writing blog. It's a tale of adventure on the high seas, set in the Red Sea between Africa and Arabia around 100 AD. The protagonist is a Kushite admiral hunting down Arabian pirates to avenge the loss of her brother, but little is she prepared for what really happened to him...

You can read the full story here. But allow me to give you a tasty sample of it below:

100 AD

A commotion buzzed at the edge of the trading souq next to the harbor of al-Mukha on the southwestern coast of Arabia. All eyes of the spectators followed a slender galley of ebony fringed with gold and inlaid ivory as it slid and anchored beside one of the earthen quays. On its billowing crimson sail glowered the gold face of a ram supporting the sun on its horns, the royal insignia of Kush.

It was by no means unusual for a Kushite vessel to dock at al-Mukha. Plenty of merchants from all sides of the Red Sea and beyond would flock to the Himyarite port to sell their wares and restock for the next trip. Yet the black galley that had come in was a rare giant that would have dwarfed the typical merchantman, never mind the puny native dhows. Above the deck glimmered the iron-bladed spears, axes, and swords of the soldiers aboard.

Once they laid the gangplank down, there descended a svelte woman whose skin was dark as the galley itself, with her short ringlets of frizzy hair reddened with ocher. The black-spotted red sash around her bosom bound a bow and quiver to her back while a slim sword rested along her white linen skirt. From her neck hung a string of ivory fly-shaped medals that honored her as a fighting champion of Kush.

After the woman followed her entourage of spearmen with oval cowhide shields. As she and her bodyguards advanced up the quay, the audience that had watched their arrival parted to give them as broad a berth as they could, with nervous murmurs in Himyarite Arabic passing between the spectators.

Placing both hands on her hip, the woman cleared her throat with her head held up. “I am Nensela, Admiral of Kush. You need not fear anything, for we mean you no harm. We come to al-Mukha with only two purposes: to resupply and to find information.”

From the ranks of the crowd, a white-bearded local shot his bony hand up. “What do you mean by ‘information’, my lady?”

Nensela pulled out a scroll of papyrus from her belt and unfolded it, revealing a painted illustration of a blue scorpion with claws serrated like a lobster’s. “Have any of you ever heard of the Scorpions of the Sea?”

Most of the people dispersed back to the souq while the old man squinted at the scroll, his tawny face blanching a shade paler. “By Rahmanan, who in al-Mukha hasn’t? They come here every season. Are they wanted?”

Nensela marched to him with her hand clenched on her sword’s hilt. “I hope you are not feigning ignorance with me, old man. You ought to know they’ve been a menace for generations. Why, I lost my little brother to them! So, please, tell me everything you know!”

The old Himyarite scratched the back of his keffiyeh and shook his head. “The truth is, I recall not when they last dropped by. But Hussein the pot merchant may know. He’s done business with them more than once. I’d look for him in the northeast part of the souq, over there.”

He pointed his walking stick in the direction of the souq‘s far corner.

Nensela tossed him a bag of silver. “May Amun bless you for your aid, then.”

The souq of al-Mukha was a bustling maze of people thronging between rows of stalls that were shaded with awnings of sagging cloth. Most of the traders and their customers were native Himyarites and other Arabs, along with similar-looking peoples such as Judaeans, Phoenicians, and Mesopotamians. Yet speckled amid the bronze-faced majority were darker-skinned nationalities such as Kemetians, Aksumites, and even a few Kushites, the latter of whom saluted Nensela and her men as they passed. The fragrances of perfume, fresh fruit, and cooked meat mixed in the air with the less pleasant odors of fish, musty cloth, and camels being dragged about on rope leashes.

Over the chatter of the customers and the music of trilling flutes, twanging lyres, and banging drums, Nensela heard a man yell about having the finest collection of ceramics along the Red Sea. That must have been the pot merchant the old man at the docks had cited.

Taking advantage of her feminine wile, she smiled and swayed her hips as she sauntered towards his stall. “You wouldn’t happen to be a handsome gentleman by the name of Hussein, would you?”

A toothy grin spread across the man’s pudgy face as he nodded. “Well, aren’t you a welcome sight around here! Of course, it is I, Hussein bin Abdullah. Why, did someone recommend my wares to you?”

All over his stall and beside it stood stacks of almost every ceramic form that could be found all over the known world. Wide-topped Kemetian jars inscribed with hieroglyphic texts sat beside orange-and-black Greek vases, Chinese porcelain, and native Arabian oil lamps with elongated nozzles. Nensela noticed there were also some Kushite bowls on display, distinguished from the rest by their black tops grading to red towards the bottom. She could not help but pick one of them up, for it had reminded her of the bowls her mother would make for her and her brother Akhraten to eat from when they were children.

Those were simpler, happier times. But they had fallen into the past. With them had gone Akhraten, all courtesy of the vile Sea Scorpions.

“My mother made pots like this,” Nensela said. “Where do you get these, my dear Hussein?”

Hussein’s eyes twitched sideways. “I’m afraid my suppliers wish to remain anonymous.”

“Oh, is that so? Because I’ve been informed that you have connections with those known as the Sea Scorpions…”

“What? Don’t be silly, woman!”

Nensela slammed her hands onto the stall, shaking the stacks of pottery until some of it fell and shattered on the ground. “Tell me the truth, Hussein bin Abdullah. When did you last deal with them?”

“I can’t say, but it isn’t them! I swear by Rahmanan, I would never profit from piracy!”

Nensela grabbed him by the collar of his tunic and hauled him off his feet. “Do not lie to me anymore! Tell me, for the safety of all around the Red Sea, whom you get your goods from. Do you hear me? Talk!”

Hands clapped as loud as the crack of thunder, and then the whole souq fell silent.

The one who had clapped was a stout Himyarite man, robed in black, with a white keffiyeh draped over the sides of his head. Everyone else in the souq stepped back to make way for him as he hurried towards Nensela and Hussein with a gentle smile under his gray-streaked mustache.

“There is no need for violence, my child,” he said. “Please put him down.”

Nensela obeyed with a grumble. “Please, do not call me ‘child’, for I am the Admiral of Kush. And I’ve good reason to believe this Hussein character is collaborating with pirates!”

“It is a lie, I assure you!” Hussein yelped.

“I will assess the truth of the matter later, Hussein bin Abdullah,” the black-robed man said. “Pardon me for my condescension there, O Admiral of Kush, but I am the Sheikh of al-Mukha. These are all my people, so I must implore you that you treat them with care while you are here.”

“You are the Sheikh?” Nensela bowed at the waist before him. “Then I must apologize for my behavior. I must admit I have little love for pirates, or those I am told are involved with their crimes.”

From the corner of her eye, she cast a glare at Hussein while he was picking up pieces of broken pottery. He repaid with a rude look of his own.

“You speak of pirates, Admiral? It so happens that I have information of my own on them,” the Sheikh of al-Mukha said. “And unlike that gentleman over there, I’ll be more than willing to share it…within the privacy of my own home, mind you. Why don’t you and your men come over for some refreshment after your long voyage?”

To be continued...

Artist’s impression of an exomoon (left) orbiting a giant planet around a distant star. Credit: Helena Valenzuela Widerström

Topics: Astronomy, Astrophysics, Exomoon, Exoplanets

And then there were two—maybe. Astronomers say they have found a second plausible candidate for a moon beyond our solar system, an exomoon, orbiting a world nearly 6,000 light-years from Earth. Called Kepler-1708 b-i, the moon appears to be a gas-dominated object, slightly smaller than Neptune, orbiting a Jupiter-sized planet around a sunlike star—an unusual but not wholly unprecedented planet-moon configuration. The findings appear in Nature Astronomy. Confirming or refuting the result may not be immediately possible, but given the expected abundance of moons in our galaxy and beyond, it could further herald the tentative beginnings of an exciting new era of extrasolar astronomy—one focused not on alien planets but on the natural satellites that orbit them and the possibilities of life therein.

There are more than 200 moons in our solar system, and they have an impressive array of variations. Saturn’s moon Titan possesses a thick atmosphere and frigid hydrocarbon seas on its surface, possibly an analog of early Earth. Icy moons such as Jupiter’s Europa are frozen balls that hide subsurface oceans, and they may be prime habitats for life to arise. Others still, such as our own moon, are apparently barren wastelands but could have water ice in their shadowed craters and maze-like networks of tunnels running underground. An important shared trait among these worlds, however, is their mere existence: six of the eight major planets of our solar system have moons. Logic would suggest the same should be true elsewhere. “Moons are common,” says Jessie Christiansen of the California Institute of Technology. “In our solar system, almost everything has a moon. I am very confident that moons are everywhere in the galaxy.”

Astronomers Have Found Another Possible ‘Exomoon’ beyond Our Solar System, Jonathan O'Callaghan, Scientific American

Image: Artist’s impression of a Dyson sphere under construction. Credit: Steve Bowers.

Topics: Astronomy, Astrophysics, Dyson Sphere, SETI

Although the so-called Dysonian SETI has been much in the air in recent times, its origins date back to the birth of SETI itself. It was in 1960 – the same year that Frank Drake used the National Radio Astronomy Observatory in Green Bank, West Virginia to study Epsilon Eridani and Tau Ceti – that Freeman Dyson proposed the Dyson sphere. In fiction, Olaf Stapledon had considered such structures in his novel Star Maker in 1937. As Macy Huston and Jason Wright (both at Penn State) remind us in a recent paper, Dyson’s idea of energy-gathering structures around an entire star evolved toward numerous satellites around the star rather than a (likely unstable) single spherical shell.

We can’t put the brakes on what a highly advanced technological civilization might do, so both solid sphere and ‘swarm’ models can be searched for, and indeed have been, for in SETI terms we’re looking for infrared waste heat. And if we stick with Dyson (often a good idea!), we would be looking for structures orbiting in a zone where temperatures would range in the 200-300 K range, which translates into searching at about 10 microns, the wavelength of choice. But Huston and Wright introduce a new factor, the irradiation from the interior of the sphere onto the surface of the star.

This is intriguing because it extends our notions of Dyson spheres well beyond the habitable zone as we consider just what an advanced civilization might do with them. It also offers up the possibility of new observables. So just how does such a Dyson sphere return light back to a star, affecting its structure and evolution? If we can determine that, we will have a better way to predict these potential observables. As we adjust the variables in the model, we can also ponder the purposes of such engineering.

Think of irradiation as Dyson shell ‘feedback.’ We immediately run into the interesting fact that adding energy to a star causes it to expand and cool. The authors explain this by noting that total stellar energy is a sum of thermal and gravitational energies. Let’s go straight to the paper on this. In the clip below, E_* refers to the star’s total energy, with E_therm being thermal energy:

When energy is added to a star (E_∗ increases), gravitational energy increases and thermal energy decreases, so we see the star expand and cool both overall (because E_therm is lower) and on its surface (because being larger at the same or a lower luminosity its effective temperature must drop). A larger star should also result in less pressure on a cooler core, so we also expect its luminosity to decrease.

Dyson Sphere ‘Feedback’: A Clue to New Observables? Paul Gilster, Centauri Dreams

Evolutionary and Observational Consequences of Dyson Sphere Feedback, Macy Huston, Jason Wright, Astrophysical Journal

I, Brandon S. Pilcher, would like to announce that I have a new historical-fiction novella out now. It's a romantic, action-packed, and multicultural tale set in southern Africa in the year 1215 AD, during the Middle Ages.

The Slave Prince of Zimbabwe

Coverage of the EEIC ANIMATION & GAMING SUMMIT

on November 20, 2021 was featured in the Los Angeles

Sentinel Newspaper and E-paper. This was a great event,

hope to attend next year’s version. Check out the article

on page 7 or 8 at the link provided HERE!

Topics: Battery, Energy, Green Tech, Research, Solid-State Physics

Janus, in Roman religion, the animistic spirit of doorways (januae) and archways (Jani). Janus and the nymph Camasene were the parents of Tiberinus, whose death in or by the river Albula caused it to be renamed Tiber. Source: Encylopedia Britannica

Over the past decade, lithium-ion batteries have seen stunning improvements in their size, weight, cost, and overall performance. (See Physics Today, December 2019, page 20.) But they haven’t yet reached their full potential. One of the biggest remaining hurdles has to do with the electrolyte, the material that conducts Li⁺ ions from anode to cathode inside the battery to drive the equal and opposite flow of charge in the external circuit.

Most commercial lithium-ion batteries use organic liquid electrolytes. The liquids are excellent conductors of Li⁺ ions, but they’re volatile and flammable, and they offer no defense against the whisker-like Li-metal dendrites that can build up between the electrodes and eventually short-circuit the battery. Because safety comes first, battery designers must sacrifice some performance in favor of not having their batteries catch fire.

A solid-state electrolyte could solve those problems. But what kind of solid conducts ions? An ordered crystal won’t do—when every site is filled in a crystalline lattice, Li⁺ ions have nowhere to move to. A solid electrolyte, therefore, needs to have a disordered, defect-riddled structure. It must also provide a polar environment to welcome the Li⁺ ions, but with no negative charges so strong that the Li⁺ ions stick to them and don’t let go.

For several years, Jenny Pringle, Maria Forsyth, and colleagues at Deakin University in Australia have been exploring a class of materials, called organic ionic plastic crystals (OIPCs), that could fit the bill. As a mix of positive and negative ions, an OIPC offers the necessary polar environment for conducting Li⁺. And because the constituent ions are organic, the researchers have lots of chemical leeways to design their shapes so they can’t easily fit together into a regular lattice but are forced to adopt a disordered, Li⁺-permeable structure.

Two-faced ions form a promising battery material, Johanna L. Miller, Physics Today