The earliest modern humans in Europe mastered bow-and-arrow technology 54,000 years ago

To test the ballistic properties of the stone points found in the Mandrin cave, modern duplicates were created and hafted on to shafts, as they may have been 54,000 years ago. Laure Metz, Ludovic Slimak, CC BY-SA

Laure Metz, Aix-Marseille Université (AMU); Jason E. Lewis, Stony Brook University (The State University of New York), and Ludovic Slimak, Université Toulouse – Jean Jaurès

Based on research in France’s Mandrin cave, in February 2022 we published a study in the journal Science Advances that pushed back the earliest evidence of the arrival of the first Homo sapiens in Europe to 54,000 years ago – 11 millennia earlier than had been previously established.

In the study, we described nine fossil teeth excavated from all the archeological layers in the cave. Eight were determined to be from Neanderthals, but one from one of the middle layers belonged to a paleolithic Homo sapiens. Based on this and other data, we determined that these early Homo sapiens of Europe were later replaced by Neanderthal populations.

The single Homo sapiens tooth was discovered in a remarkable and rich archeological layer that also included approximately 1,500 tiny stone blades or bladelets – some were less than 1 centimeter in length. They were all part of the “Neronian” tradition, named in 2004 by one of us, Ludovic Slimak, after the Néron cave in France’s Ardèche region. Neronian stone tools are distinctive and there were no similar points found in the layers left behind by the Neanderthals who inhabited the rock shelter before and after. They also bear striking parallels with those made by other Homo sapiens along the east Mediterranean coast, as exemplified at the site of Ksar Akil northeast of Beirut.

View of archeological excavations at the entrance of France’s Mandrin cave. Ludovic Slimak, CC BY-ND

This month in the journal Science Advances, we published a study announcing that the humans who arrived in Europe some 54,000 years ago had mastered the use of bows and arrows. This discovery pushes back the origin in Eurasia of these remarkable technologies by approximately 40,000 years.

The emergence in prehistory of mechanically propelled weapons – spears or arrows sent on their way by throwing sticks (atlatl) or bows – is commonly perceived as one of the hallmarks of the advance of modern human populations into the European continent. However, the origin of archery has always been archeologically difficult to trace because the materials used tend to disappear from the fossil record.

Archaeological invisibility

Armatures – hard points made of stone, horn or bone – constitute the main evidence of weapon technologies in the European Paleolithic. Materials associated with archery – wood, fibres, leather, resins, and sinew – are perishable, however, and so are rarely preserved. This makes archaeological recognition of these technologies difficult.

Partially preserved archery equipment was found in Eurasia only in more recent times, between 10 and 12 millennia ago, and in frozen ground or peat bogs, as at the Stellmoor site in Germany. Based on the analysis of armatures, archery is now well documented in Africa approximately 70,000 years ago. While some flint or deer-antler armatures suggest the existence of archery from the early phases of the Upper Paleolithic in Europe more than 35,000 years ago, their shape and how they were hafted – attached to a shaft or handle – do not allow confirmation that they were propelled by a bow.

More recent armatures from the European Upper Paleolithic bear similarities to each other, not allowing us to clearly determine whether they were propelled by a bow or an atlatl. This makes the possible existence of archery during the European Upper Paleolithic archeologically plausible, but difficult to establish.

Experimental replicas

The stone points found in the Mandrin cave are both extremely light (30% weigh hardly more than a few grams) and small (almost 40% of these tiny points present a maximum width of 10mm).

To determine how they could have been propelled, the first step was to make experimental replicas. We then hafted the newly made points into shafts and tested how they behaved when shot with bows and spear-throwers, or by simply thrusting them. This allowed us to test their ballistic characteristics, limits and efficiency.

The tiny experimental points were used as arrowheads and shot by bow or atlatl, and the resulting fractures were compared with the scars found on the archeological material. Laure Metz, Slimak Ludovic, CC BY-ND

After our experimental replicas were shot, we examined the fractures that resulted and compared them with those found on the archeological material. The fractures and scars show that they were distally hafted – attached to the split end of a shaft. Their small size and especially narrow width allow us to conclude how they were fired: only high-speed propulsion by a bow was possible, our analysis determined.

Nanotechnologies of the first Homo sapiens in Europe. More than 1,500 points were found abandoned by these earliest modern humans during their stay in Mandrin cave. This very light point, found in the cave’s Layer E, is dated to 54,000 years old and presents diagnostic microscopic scars of its use as a weapon. Laure Metz, Ludovic Slimak, CC BY-ND

The data from the Mandrin cave and the tests that we performed enrich our knowledge of these technologies in Europe and now allow us to push back the age of archery in Europe by more than 40,000 years.

Our study also sheds light on the weaponry of these Neanderthal populations, who were contemporaries of the Neronian modern humans. Neanderthals did not develop mechanically propelled weapons and continued to use their traditional weapons based on the use of massive stone-tipped spears that were thrust or thrown by hand, and thus requiring close contact with the game they hunted. The traditions and technologies mastered by these two populations were thus distinct, illustrating a remarkable objective technological advantage for modern populations during their expansion into Europe.

Not only do these discoveries profoundly reshape our knowledge of Neanderthals and modern humans in Western Europe, but they also raise many questions about the structure and organization of these different populations on the continent. Technical choices are not solely the result of the cognitive capacities of differing hominin populations, but may also have depended on the weight of traditions within these Neanderthal and modern human populations.

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To deepen one’s understanding the complex question of the relationship between Homo sapiens and Neanderthals during the first migration to the European continent, the reader can turn to Ludovic Slimak’s book “Néandertal nu” (Odile Jacob 2022), soon available from Penguin books as “The Naked Neanderthal”.

Laure Metz, Archéologue et chercheuse en anthropologie, Aix-Marseille Université (AMU); Jason E. Lewis, Lecturer of Anthropology and Assistant Director of the Turkana Basin Institute, Stony Brook University (The State University of New York), and Ludovic Slimak, CNRS Permanent Member, Université Toulouse – Jean Jaurès

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How Edgar Allan Poe became the darling of the maligned and misunderstood

Could the pugnacious writer ever have imagined that he would one day become a cult hero? Nick Lehr/The Conversation via DALL-E 2, CC BY-SA

Scott Peeples, College of Charleston

Edgar Allan Poe, who would have turned 214 years old on Jan. 19, 2023, remains one of the world’s most recognizable and popular literary figures.

His face – with its sunken eyes, enormous forehead and disheveled black hair – adorns tote bags, coffee mugs, T-shirts and lunch boxes. He appears as a meme, either sporting a popped collar and aviator shades as Edgar Allan Bro, or riffing on “Bohemian Rhapsody” by muttering, “I’m just Poe boy, nobody loves me” as a raven on his shoulder adds, “He’s just a Poe boy from a Poe family.”

Netflix has sought to capitalize on the writer’s popularity, recently releasing the mystery-thriller “The Pale Blue Eye,” which features Poe as a West Point cadet, where he spent less than a year before being court-martialed. Netflix also has a Poe-inspired miniseries, “The Fall of the House of Usher,” set to be released sometime in 2023.

But as a Poe scholar, I sometimes wonder whether Poe’s appeal is less about the power and complexity of his prose and more about an attraction to the idea of Poe.

After all, Poe’s most famous literary creations tend to be unsympathetic villains. There are psychopaths who perpetuate seemingly motiveless murders in “The Black Cat” and “The Tell-Tale Heart”; protagonists who abuse women in “Ligeia” and “The Fall of the House of Usher”; and characters who exact cruel, fatal revenge on unwitting victims in “The Cask of Amontillado” and “Hop-Frog.”

The degenerate characters whose perspectives Poe invites readers to inhabit don’t exactly align with a cultural moment characterized by the #MeToo movement, safe spaces and trigger warnings.

At the same time, the conception of Poe the writer seems to tap into a cultural affection for outsiders, nonconformists and underdogs who ultimately prove their worth.

A character assassination that misfires

The idea of Poe the underdog began with his death in 1849, which was greeted by a cruel notice in the New York Tribune: “This announcement will startle many, but few will be grieved by it.”

The obituary writer, who turned out to be Poe’s sometime friend and constant rival Rufus W. Griswold, claimed that the deceased had “few or no friends” and proceeded with a general character assassination built on exaggerations and half-truths.

Strange as it seems, Griswold was also Poe’s literary executor, and he expanded the obituary into a biographical essay that accompanied Poe’s collected works. If this was a marketing ploy, it worked. The friends that Griswold claimed Poe lacked rose to his defense, and journalists spent decades debating who the man really was.

Rufus W. Griswold penned the first draft of Poe’s life and legacy. raveler1116/DigitalVision Vectors via Getty Images

During Poe’s lifetime, most readers encountered his work through magazines, and he was rarely well paid. But Griswold’s edition went through 19 printings in the 15 years after Poe’s death, and his stories and poems have been endlessly reprinted and translated ever since.

Griswold’s defamatory portrait, along with the grim subject matter of Poe’s stories and poems, still influences the way readers perceive him. But it has also produced a sustained reaction or counterimage of Poe as a tragic hero, a tortured, misunderstood artist who was too good – or, at any rate, too cool – for his world.

While translating Poe’s works into French in the 1850s and 1860s, the French poet Charles Baudelaire promoted his hero as a kind of countercultural visionary, out of step with a moralistic, materialistic America. Baudelaire’s Poe valued beauty over truth in his poetry and, in his fiction, saw through the self-improvement pieties that were popular at the time to reveal “the natural wickedness of man.” Poe struck a chord with European writers, and as his international stature rose in the late 19th century, literary critics in the U.S. wrung their hands over his lack of appreciation “at home.”

Poe’s underdog story takes off

By the turn of the 20th century, the stage was set for Poe to be embraced as the perennial underdog. And Poe often did appear on stage around this time, as the subject of several biographical melodramas that depicted him as a tragic figure whose lack of success had more to do with a hostile cultural and publishing environment than his own failings.

That image appeared on the silver screen as early as 1909 in D.W. Griffith’s short film “Edgar Allen Poe.” With Poe’s wife, Virginia, languishing on a sick bed, the poet ventures out to sell “The Raven.” After meeting rejection and scorn, he manages to sell his manuscript and returns home with provisions for his ailing wife, only to find that she has died.

Later films also depict Poe as being misunderstood or underappreciated in his lifetime. A wildly inaccurate biopic, “The Loves of Edgar Allan Poe,” released in 1942, ends with a voice-over commenting, “…little did [the public] know that the manuscript of ‘The Raven,’ which he tried in vain to sell for $25, would years later bring the price of $17,000 from a collector.”

In ‘The Loves of Edgar Allan Poe,’ Poe’s talents are overlooked, as ‘men scoffed at his greatness.’ LMPC/Getty Images

In real life, while an early draft of “The Raven” was declined by one editor, Poe had no trouble selling the poem, and it was an immediate sensation.

But here “The Raven” becomes a stand-in for Poe himself, something dark and mysterious that, according to legend, people in Poe’s time failed to appreciate.

Poe is an obscure writer and amateur detective in the 1951 film “The Man with a Cloak,” which ends with a saloonkeeper allowing the rain to wash away the ink on an IOU that Poe gave him. On the reverse side of the note is a manuscript of the poem “Annabel Lee,” as its bearer declares, “That name’ll never be worth anything. Not in a hundred years.”

Of course, the audience watching this film almost exactly 100 years after Poe’s death knew better.

The most interesting plants grow in the shade

Which brings us to “The Pale Blue Eye,” in which Henry Melling portrays Cadet Poe, an outcast with a keen crime solver’s intellect. In a refreshing change, this younger Poe is not a tortured artist or a haunted, brooding figure. He is, however, picked on by his peers and underestimated by his superiors – yet again, an underdog viewers want to root for.

In that sense, the Poe in “The Pale Blue Eye” fits well with his contemporary image, which also permeates the early episodes of “Wednesday,” Netflix’s Addams Family spinoff set at Nevermore Academy that’s chock full of Poe references.

The headmistress of Nevermore Academy – a Hogwarts-like school for outcasts – refers to Poe as “our most famous alumni,” which explains why the school’s annual boat race is the Poe Cup and why there’s a statue of Poe guarding a secret passage.

The delightfully antisocial protagonist, Wednesday, played by Jenna Ortega, is an outcast among outcasts – the Poe figure at a school whose name evokes Poe. In one scene, a sympathetic teacher urges her not to lose “the ability to not let others define you. It’s a gift.” She adds, “The most interesting plants grow in the shade.”

When John Lennon sang “Man, you should have seen them kicking Edgar Allan Poe” in “I Am the Walrus,” he didn’t have to say who was kicking him or why. The point was, Poe deserved better; the most interesting plants do grow in the shade, unlovely and unloved.

And that’s exactly why so many people – aspiring writers and artists, but also everyone when they’re lonely and misunderstood – see a little bit of themselves in the weary-but-wise image of Poe.

Scott Peeples, Professor of English, College of Charleston

This article is republished from The Conversation under a Creative Commons license. Read the original article.

3D-printing the brain’s blood vessels with silicone could improve and personalize neurosurgery – new technique shows how

3D printers can lay down more than just layers of melted plastic. Dedraw Studio/iStock via Getty Images Plus

Senthilkumar Duraivel, University of Florida and Thomas Angelini, University of Florida

A new 3D-printing technique using silicone can make accurate models of the blood vessels in your brain, enabling neurosurgeons to train with more realistic simulations before they operate, according to our recently published research.

Many neurosurgeons practice each surgery before they get into the operating room based on models of what they know about the patient’s brain. But the current models neurosurgeons use for training don’t mimic real blood vessels well. They provide unrealistic tactile feedback, lack small but important structural details and often exclude entire anatomical components that determine how each procedure will be performed. Realistic and personalized replicas of patient brains during pre-surgery simulations could reduce error in real surgical procedures.

3D printing, however, could make replicas with the soft feel and the structural accuracy surgeons need.

3D printing is typically thought of as a process that involves laying down layer after layer of melted plastic that solidifies as a self-supporting structure is built. Unfortunately, many soft materials do not melt and re-solidify the way the plastic filament that 3D printers typically employ do. Users only get one shot with soft materials like silicone – they have to be printed while in a liquid state and then irreversibly solidified.

Researchers are exploring 3D-printing organs using living cells.

Shaping liquids in 3D

How do you make a complex 3D shape out of a liquid without ending up with a puddle or a slumping blob?

Researchers developed a broad approach called embedded 3D printing for this purpose. With this technique, the “ink” is deposited inside a bath of a second supporting material designed to flow around the printing nozzle and trap the ink in the place right after the nozzle moves away. This allows users to create complex shapes out of liquids by holding them trapped in three-dimensional space until the time comes to solidify the printed structure. Embedded 3D printing has been effective for structuring a variety of soft materials like hydrogels, microparticles and even living cells.

However, printing with silicone has remained challenging. Liquid silicone is an oil, while most support materials are water-based. Oil and water have a high interfacial tension, which is the driving force behind why oil droplets take on circular shapes in water. This force also causes 3D-printed silicone structures to deform, even in a support medium.

Interfacial tension is what causes oil droplets to form on water and silicone to deform. Baac3nes/Moment via Getty Images

Even worse, these interfacial forces drive small-diameter silicone features to break into droplets as they are being printed. A lot of research has gone into making silicone materials that can be printed without a support, but these heavy modifications also modify the properties that users care about, like how soft and stretchy the silicone is.

3D-printing silicone with AMULIT

As researchers working at the interface of soft matter physics, mechanical engineering and materials science, we decided to tackle the problem of interfacial tension by developing a support material made from silicone oil.

We reasoned that most silicone inks would be chemically similar to our silicone support material, thus dramatically reducing interfacial tension, but also different enough to remain separated when put together for 3D printing. We created many candidate support materials but found that the best approach was to make a dense emulsion of silicone oil and water. One can think about it like crystal clear mayonnaise, made from packed microdroplets of water in a continuum of silicone oil. We call this method additive manufacturing at ultra-low interfacial tension, or AMULIT.

This diagram shows the AMULIT technique printing the bronchi of a lung model within a bath of supporting material. At right is a close-up of the needle depositing layers of silicone to make the tissue. Senthilkumar Duraivel/Angelini Lab, CC BY-ND

With our AMULIT support medium, we were able to print off-the-shelf silicone at high resolution, creating features as small as 8 micrometers (around 0.0003 inches) in diameter. The printed structures are as stretchy and durable as their traditionally molded counterparts.

These capabilities enabled us to 3D-print accurate models of a patient’s brain blood vessels based on a 3D scan as well as a functioning heart valve model based on average human anatomy.

3D silicone printing in health care

Silicone is a critical component of innumerable products, from everyday consumer goods like cookware and toys to advanced technologies in the electronics, aerospace and health care industries.

Silicone products are typically made by pouring or injecting liquid silicone into a mold and removing the cast after solidification. The expense and difficulty of manufacturing high-precision molds limits manufacturers to products with only a few predetermined sizes, shapes and designs. Removing delicate silicone structures from molds without damage is an additional barrier, and manufacturing defects increase when molding highly intricate structures.

Overcoming these challenges could allow for the development of advanced silicone-based technologies in the health care industry, where personalized implants or patient-specific mimics of physiological structures could transform care.

Senthilkumar Duraivel, Ph.D. Candidate in Materials Science and Engineering, University of Florida and Thomas Angelini, Associate Professor of Mechanical and Aerospace Engineering, University of Florida

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Israel’s military reservists are joining protests – potentially transforming a political crisis into a security crisis

A member of Israel’s military reserves takes part in a protest on March 16, 2023 in Bnei Brak, a city east of Tel Aviv. Photo by Eyal Warshavsky/SOPA Images/LightRocket via Getty Images

Dan Arbell, American University

The judicial overhaul plan of Israeli Prime Minister Benjamin Netanyahu’s government, introduced in January, has thrown the country into its most severe domestic crisis since 1973.

The plan has incited an unprecedented wave of controversy among Israelis, as hundreds of thousands of protestors have gathered for a 12th straight week across the country in opposition to the plan. Yet it’s not simply the persistence and size of the protest that is evidence of the crisis. It’s who is protesting.

The demonstrations have brought together groups representing almost all sectors of Israeli society. But among protesters is a group of individuals rarely seen at anti-government protests over the country’s almost 75-year history: Israeli Defense Forces reservists. They include former combat pilots, members of elite units and special forces, cyber-security forces and military intelligence, who announced they will not volunteer for reserve duty service if the legislation passes in the Knesset, Israel’s parliament.

Further demonstrating the unprecedented aspect of the response by reservists: Among those protesting are members of Israeli Air Force Squadron 69. All but three of the 40 reservist pilots in the squadron announced that they would not conduct training exercises and would instead join anti-government protests, claiming they are not prepared to serve in what they say would be a “dictatorial regime.”

“We have no contract with a dictator. We would be happy to volunteer when the democracy is safeguarded,” an open letter from the reservists said.

The highly controversial judicial reform plan would significantly weaken the Israeli judiciary’s oversight over the legislative and executive branches.

The plan calls for near total control over future laws, constitutional amendments and judicial appointments to be concentrated in the hands of the governing coalition in the Knesset. Critics and protesters say the plan undermines the 75-year delicate balance between the three government branches, ends liberal democracy as they know it and pushes Israel towards autocratic rule.

Despite the growing protests, Netanyahu has defiantly promised to push the reforms through the Knesset. As the country inches closer towards a constitutional showdown between the executive and legislative branches and the judicial branch, the presence of former members of elite military units in these protests is evidence that the crisis’ implications extend far beyond the domestic political arena.

Besides threatening to undermine the economy and deepen societal divides, it threatens to erode Israeli national security and provoke a constitutional crisis that could ensnare the military as well.

Israel Defense Minister Yoav Gallant called for an immediate halt in the judicial overhaul legislation process. Gil Cohen-MAGEN/AFP via Getty Images)

‘The people’s army’

Israel’s military, known as the “IDF,” has been described for decades as the “people’s army.” That’s because young Israeli men and women, when they turn 18, are mandated by law to serve in the military. Men serve for two years and eight months and women for two years.

Upon completion of their regular military service, men and women are assigned to the reserve forces. The reserves are designed to provide reinforcements during emergencies and maintain preparedness through routine training and security assignments. While the number of Israelis serving as reservists has decreased over the years due to cutbacks and people finding ways to be exempted, reserve military service has been an integral part of the national ethos and folklore.

The threat to the government articulated by the protesting reservists is unprecedented. It represents a powerful step by former military and intelligence officials who pride themselves on their independence from politics and commitment to protocol.

Nevertheless, the reservists’ view is that there is an unwritten contract between those who serve and the state: they are willing to risk their lives to defend a liberal democratic Israel. But if Israel becomes a dictatorship, this contract is null and void.

It is possible that other security services like the police or Shin Bet, the internal security service, will take similar actions to protest the reforms. Depending on how long these protests last, the situation could unfold into an uncharted security crisis with high risks of domestic instability and, as Israeli President Isaac Herzog warned, civil strife.

Israelis protest the proposed judicial reform, in Tel Aviv on March 25, 2023. Gitai Palti/Anadolu Agency via Getty Images

Defense of democracy - or insubordination?

Minister of Defense Yoav Gallant, addressing the situation on March 25, 2023, expressed deep concern that the heated political debate is infiltrating the rank and file of the IDF. And that, Gallant said, may undermine and jeopardize Israel’s security at a time when the country faces external threats from Iran, Palestinian terrorism and Lebanese Hezbollah.

“The events taking place in Israeli society do not spare the Israel Defense Forces — from all sides, feelings of anger, pain and disappointment arise, with an intensity I have never encountered before,” Gallant said.

Gallant called for an immediate halt in the judicial overhaul legislation process. Instead, he proposed a dialogue between the two sides in order to reach a broadly agreed reform.

As a veteran of the IDF, a former Israeli diplomat and a longtime analyst of Israel’s security situation, I believe the crisis poses a profound question of where the line is between legal political activism in defense of democracy and insubordination.

The bigger question is what will happen with the military if the legislation passes in the Knesset, but is then struck down by Israel’s supreme court, the High Court of Justice. Should Netanyahu’s government request that institutions like the IDF act in contradiction to decisions made by the High Court, it is unclear to which authority these institutions would adhere.

For example: if the High Court rules that a Jewish outpost in the West Bank was built illegally and needs to be dismantled, yet the government orders the IDF not to do it, what will the IDF commanders on the ground do?

This tension is starkly displayed by the reservists who are refusing to partake in their usual duties.

In light of Gallant’s call to halt the legislation process, it is unclear whether the voting on the changes in the makeup of the Judges Selection Committee, scheduled for the week of March 26, 2023, will take place as planned.

The reservists’ active participation in the protests and their vocal opposition to the government’s plan have clearly made an impact on the defense minister. But at the same time, Gallant came out strongly against insubordination. Undoubtedly, the coming days will be critical in determining the direction of Israeli democracy.

Dan Arbell, Scholar-in-residence at the Center for Israeli Studies, American University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How do superconductors work? A physicist explains what it means to have resistance-free electricity

Magnetic levitation is just one of the interesting attributes that make superconductors so interesting. Mark Garlick/Science Photo Library vie Getty Images

Mishkat Bhattacharya, Rochester Institute of Technology

The modern world runs on electricity, and wires are what carry that electricity to every light, television, heating system, cellphone and computer on the planet. Unfortunately, on average, about 5% of the power generated at a coal or solar power plant is lost as the electricity is transmitted from the plant to its final destination. This amounts to a US$6 billion loss annually in the U.S. alone.

For decades, scientists have been developing materials called superconductors that transmit electricity with nearly 100% efficiency. I am a physicist who investigates how superconductors work at the atomic level, how current flows at very low temperatures, and how applications such as levitation can be realized. Recently, researchers have made significant progress toward developing superconductors that can function at relatively normal temperatures and pressures.

To see why these recent advances are so exciting and what impact they may have on the world, it’s important to understand how superconducting materials work.

Most materials offer resistance when electricity runs through them and heat up. Resistance is how filaments in an incandescent lightbulb produce light. Ulfbastel/Wikimedia Commons, CC BY-SA

A resistance-free material

A superconductor is any material that conducts electricity without offering any resistance to the flow of the electric current.

This resistance-free attribute of superconductors contrasts dramatically with standard conductors of electricity – like copper or aluminum – which heat up when current passes through them. This is similar to quickly sliding your hand across a smooth, slick surface compared to sliding your hand over a rough rug. The rug generates more friction and, therefore, more heat, too. Electric toasters and older-style incandescent lightbulbs use resistance to produce heat and light, but resistance can pose problems for electronics. Semiconductors have resistance below that of conductors, but still higher than that of superconductors.

Superconductive materials repel magnetic fields, making it possible to levitate a magnet above a superconductor.

Another characteristic of superconductors is that they repel magnetic fields. You may have seen videos of the fascinating result of this effect: It is possible to levitate magnets above a superconductor.

How do superconductors work?

All superconductors are made of materials that are electrically neutral – that is, their atoms contain negatively charged electrons that surround a nucleus with an equal number of positively charged protons.

If you attach one end of a wire to something that is positively charged, and the other end to something that is negatively charged, the system will want to reach equilibrium by moving electrons around. This causes the electrons in the wire to try to move through the material.

At normal temperatures, electrons move in somewhat erratic paths. They can generally succeed in moving through a wire freely, but every once in a while they collide with the nuclei of the material. These collisions are what obstruct the flow of electrons, cause resistance and heat up the material.

The nuclei of all atoms are constantly vibrating. In a superconducting material, instead of flitting around randomly, the moving electrons get passed along from atom to atom in such a way that they keep in sync with the vibrating nuclei. This coordinated movement produces no collisions and, therefore, no resistance and no heat.

The colder a material gets, the more organized the movement of electrons and nuclei becomes. This is why existing superconductors only work at extremely low temperatures.

Superconducting materials would allow engineers to fit many more circuits onto a single computer chip. David Carron/Wikimedia Commons, CC BY-SA

Benefits to electronics

If scientists can develop a room-temperature superconducting material, wires and circuitry in electronics would be much more efficient and produce far less heat. The benefits of this would be widespread.

If the wires used to transmit electricity were replaced with superconducting materials, these new lines would be able to carry up to five times as much electricity more efficiently than current cables.

The speed of computers is mostly limited by how many wires can be packed into a single electric circuit on a chip. The density of wires is often limited by waste heat. If engineers could use superconducting wires, they could fit many more wires in a circuit, leading to faster and cheaper electronics.

Finally, with room-temperature superconductors, magnetic levitation could be used for all sorts of applications, from trains to energy-storage devices.

With recent advances providing exciting news, both researchers looking at the fundamental physics of high-temperature superconductivity as well as technologists waiting for new applications are paying attention.

Mishkat Bhattacharya, Professor of Physics and Astronomy, Rochester Institute of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How to unlock your creativity – even if you see yourself as a conventional thinker

People engage in creative thinking every day, whether they realize it or not. Ekaterina Chizhevskaya/iStock via Getty Images

Lily Zhu, Washington State University

Do you think that creativity is an innate gift? Think again.

Many people believe that creative thinking is difficult – that the ability to come up with ideas in novel and interesting ways graces only some talented individuals and not most others.

The media often portrays creatives as those with quirky personalities and unique talent. Researchers have also identified numerous personality traits that are associated with creativity, such as openness to new experiences, ideas and perspectives.

Together, they seem to paint a dire picture for those who consider themselves conventional thinkers, as well as those who do not work in creative occupations – including roles that are often considered traditional and noncreative, such as accountants and data analysts.

These beliefs miss a key part of how creativity works in your brain: Creative thinking is actually something you engage in every day, whether you realize it or not.

Moreover, creativity is a skill that can be strengthened. This matters even for people who don’t consider themselves creative or who aren’t in creative fields.

In research that I recently published with organization and management scholars Chris Bauman and Maia Young, we found that simply reinterpreting a frustrating situation can enhance the creativity of conventional thinkers.

Using creative thinking to cope with emotions

Creativity is often defined as the generation of ideas or insights that are novel and useful. That is, creative thoughts are original and unexpected, but also feasible and useful.

Everyday examples of creativity are plentiful: combining leftover food to make a tasty new dish, coming up with a new way to accomplish chores, mixing old outfits to create a new look.

Another way you do this is when you practice what’s called “emotional reappraisal” – viewing a situation through another lens to change your feelings. There is an element of creativity to this: You’re breaking away from your existing perspectives and assumptions and coming up with a new way of thinking.

Say you’re frustrated about a parking ticket. To alleviate the bad feelings, you can think of the fine as a learning moment.

If you’re anxious about a presentation for work, you can cope with the anxiety by framing it as an opportunity to share ideas, rather than as a high-stakes performance that could result in demotion if handled poorly.

And if you’re angry that someone seemed unnecessarily combative in a conversation, you might reevaluate the situation, coming to view the behavior as unintentional rather than malicious.

Training your creative muscles

To test the link between creative thinking and emotional reappraisal, we surveyed 279 people. Those who ranked higher on creativity tended to reappraise emotional events more often in their daily life.

Inspired by the link between emotional reappraisal and creative thinking, we wanted to see whether we could use this insight to develop ways to help people be more creative. In other words, could emotional reappraisal be practiced by people in order to train their creative muscles?

We ran two experiments in which two new samples of participants – 512 in total – encountered scenarios designed to provoke an emotional response. We tasked them with using one of three approaches to manage their emotions. We told some participants to suppress their emotional response, others to think about something else to distract themselves and the last group to reappraise the situation by looking at it through a different lens. Some participants were also given no instructions on how to manage their feelings.

In a seemingly unrelated task that followed, we asked the participants to come up with creative ideas to solve a problem at work.

In the experiments, conventional thinkers who tried reappraisal came up with ideas that were more creative than other conventional thinkers who used suppression, distraction or received no instructions at all.

Cultivating flexible thinking

Negative emotions are inevitable in work and life. Yet people often hide their negative feelings from others, or use distraction to avoid thinking about their frustrations.

Our findings have implications for how managers can think about how to best leverage the skills of their workers. Managers commonly slot job candidates into creative and noncreative jobs based on cues that signal creative potential. Not only are these cues shaky predictors of performance, but this hiring practice may also limit managers’ access to employees whose knowledge and experience can play major roles in generating creative outcomes.

The result is that the creative potential of a significant part of the workforce may be underutilized. Our findings suggest that supervisors can develop training and interventions to cultivate creativity in their employees – even for those who might not seem predisposed to creativity.

Our research also indicates that people can practice flexible thinking every day when they experience negative emotions. Although people may not always have control over the external circumstances, they do have the liberty to choose how to cope with emotional situations – and they can do so in ways that facilitate their productivity and well-being.

Lily Zhu, Assistant Professor of Management, Information Systems and Entrepreneurship, Washington State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Federal Reserve’s ‘soft landing’ goal has become bumpier with rate hike plan hit by bank turbulence

A recession-free landing for the Fed may be harder now. AP Photo/Alex Brandon

Ryan Herzog, Gonzaga University

Federal Reserve policymakers have targeted a “soft landing” for the U.S. economy since beginning their effort a year ago to tame runaway inflation by hiking interest rates. That is, they believed they could do so without sending the U.S. into recession.

But the Fed’s decision to raise rates by a quarter point on March 22, 2023, and modestly lift its projection for how much higher they will go in 2024 does little to ease the growing concerns about the health of regional banks.

As an economist who studies the macroeconomy, I believe this makes the soft landing scenario less likely.

Squeezing regional banks

The Fed’s latest moves suggest policymakers don’t expect the banking sector stress to spill over into the broader economy.

Had it believed so, it probably would have paused its rate hikes entirely.

Chair Jerome Powell, in a press conference following the announcement, assured the public that the banking system is strong, sound, resilient and has ample capital.

But the hike, paired with the acknowledgment of banking sector uncertainty, acts against those very assurances by creating additional stress. It will shrink lenders’ profit margins as the cost of funding continues to rise and tighter credit conditions force banks to dial back on lending.

This will be felt most by smaller regional banks and the communities they serve. Regional banks are a valuable source of credit for small businesses and mortgage lenders. As credit conditions tighten, it is becoming more likely the Fed may have been too aggressive in raising rates over the past year.

And while the Fed has said it stands at the ready to provide liquidity to banks, that won’t stop depositors from moving their money into safer institutions offering higher returns – which increases the risk of further bank runs, similar to those that felled Silicon Valley Bank.

Recession risks rising

In congressional testimony also on March 22, Treasury Secretary Janet Yellen said the U.S. has no plans to provide “blanket insurance” for all deposits regardless of size – the current limit is US$250,000 – after earlier reports suggested that it might do just that.

Markets reacted badly to this news, coming at about the same time as the Fed decision.

Investors such as Bill Ackman worried this will lead to an acceleration of deposits fleeing regional banks.

In the end, I believe the rate hike will cause more harm in the banking sector than the Fed anticipates. And this reduces the likelihood of a soft landing – and increases the odds of recession.

Ryan Herzog, Associate Professor of Economics, Gonzaga University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why does time change when traveling close to the speed of light? A physicist explains

Time gets a little strange as you approach the speed of light. ikonacolor/iStock via Getty Images

Michael Lam, Rochester Institute of Technology

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.

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Why does time change when traveling close to the speed of light? – Timothy, age 11, Shoreview, Minnesota

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Imagine you’re in a car driving across the country watching the landscape. A tree in the distance gets closer to your car, passes right by you, then moves off again in the distance behind you.

Of course, you know that tree isn’t actually getting up and walking toward or away from you. It’s you in the car who’s moving toward the tree. The tree is moving only in comparison, or relative, to you – that’s what we physicists call relativity. If you had a friend standing by the tree, they would see you moving toward them at the same speed that you see them moving toward you.

In his 1632 book “Dialogue Concerning the Two Chief World Systems,” the astronomer Galileo Galilei first described the principle of relativity – the idea that the universe should behave the same way at all times, even if two people experience an event differently because one is moving in respect to the other.

If you are in a car and toss a ball up in the air, the physical laws acting on it, such as the force of gravity, should be the same as the ones acting on an observer watching from the side of the road. However, while you see the ball as moving up and back down, someone on the side of the road will see it moving toward or away from them as well as up and down.

Special relativity and the speed of light

Albert Einstein much later proposed the idea of what’s now known as special relativity to explain some confusing observations that didn’t have an intuitive explanation at the time. Einstein used the work of many physicists and astronomers in the late 1800s to put together his theory in 1905, starting with two key ingredients: the principle of relativity and the strange observation that the speed of light is the same for every observer and nothing can move faster. Everyone measuring the speed of light will get the same result, no matter where they are or how fast they are moving.

Let’s say you’re in the car driving at 60 miles per hour and your friend is standing by the tree. When they throw a ball toward you at a speed of what they perceive to be 60 miles per hour, you might logically think that you would observe your friend and the tree moving toward you at 60 miles per hour and the ball moving toward you at 120 miles per hour. While that’s really close to the correct value, it’s actually slightly wrong.

The experience of time is dependent on motion.

This discrepancy between what you might expect by adding the two numbers and the true answer grows as one or both of you move closer to the speed of light. If you were traveling in a rocket moving at 75% of the speed of light and your friend throws the ball at the same speed, you would not see the ball moving toward you at 150% of the speed of light. This is because nothing can move faster than light – the ball would still appear to be moving toward you at less than the speed of light. While this all may seem very strange, there is lots of experimental evidence to back up these observations.

Time dilation and the twin paradox

Speed is not the only factor that changes relative to who is making the observation. Another consequence of relativity is the concept of time dilation, whereby people measure different amounts of time passing depending on how fast they move relative to one another.

Each person experiences time normally relative to themselves. But the person moving faster experiences less time passing for them than the person moving slower. It’s only when they reconnect and compare their watches that they realize that one watch says less time has passed while the other says more.

This leads to one of the strangest results of relativity – the twin paradox, which says that if one of a pair of twins makes a trip into space on a high-speed rocket, they will return to Earth to find their twin has aged faster than they have. It’s important to note that time behaves “normally” as perceived by each twin (exactly as you are experiencing time now), even if their measurements disagree.

The twin paradox isn’t actually a paradox.

You might be wondering: If each twin sees themselves as stationary and the other as moving toward them, wouldn’t they each measure the other as aging faster? The answer is no, because they can’t both be older relative to the other twin.

The twin on the spaceship is not only moving at a particular speed where the frame of references stay the same but also accelerating compared with the twin on Earth. Unlike speeds that are relative to the observer, accelerations are absolute. If you step on a scale, the weight you are measuring is actually your acceleration due to gravity. This measurement stays the same regardless of the speed at which the Earth is moving through the solar system, or the solar system is moving through the galaxy or the galaxy through the universe.

Neither twin experiences any strangeness with their watches as one moves closer to the speed of light – they both experience time as normally as you or I do. It’s only when they meet up and compare their observations that they will see a difference – one that is perfectly defined by the mathematics of relativity.

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Hello, curious kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to CuriousKidsUS@theconversation.com. Please tell us your name, age and the city where you live.

And since curiosity has no age limit – adults, let us know what you’re wondering, too. We won’t be able to answer every question, but we will do our best.

Michael Lam, Assistant Professor of Physics and Astronomy, Rochester Institute of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Worst bank turmoil since 2008 means Federal Reserve is damned if it does and damned if it doesn’t in decision over interest rates

Just hold your nose and make a decision. AP Photo/Andrew Harnik

Alexander Kurov, West Virginia University

The Federal Reserve faces a pivotal decision on March 22, 2023: whether to continue its aggressive fight against inflation or put it on hold.

Making another big interest rate hike would risk exacerbating the global banking turmoil sparked by Silicon Valley Bank’s failure on March 10. Raising rates too little, or not at all as some are calling for, could not only lead to a resurgence in inflation, but it could cause investors to worry that the Fed believes the situation is even worse than they thought – resulting in more panic.

What’s a central banker to do?

As a finance scholar, I have studied the close link between Fed policy and financial markets. Let me just say I would not want to be a Fed policymaker right now.

Break it, you bought it

When the Fed starts hiking rates, it typically keeps at it until something breaks.

The U.S. central bank began its rate-hiking campaign early last year as inflation began to surge. After initially mistakenly calling inflation “transitory,” the Fed kicked into high gear and raised rates eight times from just 0.25% in early 2022 to 4.75% in February 2023. This is the fastest pace of rate increases since the early 1980s – and the Fed is not done yet.

Consumer prices were up 6% in February from a year earlier. While that’s down from a peak annual rate of 9% in June 2022, it’s still significantly above the Fed’s 2% inflation target.

But then something broke. Seemingly out of nowhere, Silicon Valley Bank, followed by Signature Bank, collapsed virtually overnight. They had over US$300 billion in assets between them and became the second- and third-largest banks to fail in U.S. history.

Panic quickly spread to other regional lenders, such as First Republic, and upset markets globally, raising the prospect of even bigger and more widespread bank failures. Even a $30 billion rescue of First Republic by its much larger peers, including JPMorgan Chase and Bank of America, failed to stem the growing unease.

If the Fed lifts interest rates more than markets expect – currently a 0.25 percentage point increase – it could prompt further anxiety. My research shows that interest rate changes have a much bigger effect on the stock market in bear markets – when there’s a prolonged decline in stock prices, as the U.S. is experiencing now – than in good times.

Making the SVB problem worse

What’s more, the Fed could make the problem that led to Silicon Valley Bank’s troubles even worse for other banks. That’s because the Fed is at least indirectly responsible for what happened.

Banks finance themselves mainly by taking in deposits. They then use those essentially short-term deposits to lend or make investments for longer terms at higher rates. But investing short-term deposits in longer-term securities – even ultra-safe U.S. Treasurys – creates what is known as interest rate risk.

That is, when interest rates go up, as they did throughout 2022, the values of existing bonds drop. SVB was forced to sell $21 billion worth of securities that lost value because of the Fed’s rate hikes at a loss of $1.8 billion, sparking its crisis. When SVB’s depositors got the wind of it and tried to withdraw $42 billion on March 9 alone – a classic bank run – it was over. The bank simply couldn’t meet the demands.

But the entire banking sector is sitting on hundreds of billions of dollars’ worth of unrealized losses – $620 billion as of Dec. 31, 2022. And if rates continue to go up, the value of these bonds will keep going down, which fundamentally weakens banks’ financial situation.

The Fed has been aggressively raising rates to stem the rapid increase in prices for items such as food. AP Photo/Wilfredo Lee

Risks of slowing down

While that may suggest it’s a no-brainer to put the rate hikes on hold, it’s not so simple.

Inflation has been a major problem plaguing the U.S. economy since 2021 as prices for homes, cars, food, energy and so much else jump for consumers. The last time consumer prices soared this much, in the early 1980s, the Fed had to raise rates so high that it sent the U.S. economy into recession – twice.

High inflation quickly cuts into how much stuff your money can buy. It also makes saving money more difficult because it eats at the value of your savings. When high inflation sticks around for a long time, it gets entrenched in expectations, making it very hard to control.

This is why the Fed jacked up rates so fast. And it’s unlikely it’s done enough to bring rates down to its 2% target, so a pause in lifting rates would mean inflation may stay higher for longer.

Moreover, stepping back from its one-year-old inflation campaign may send the wrong signal to investors. If central bankers show they are really concerned about a possible banking crisis, the market may think the Fed knows the financial system is in serious trouble and things are more dire than previously thought.

So what’s a Fed to do

At the very least, the complex global financial system is showing some cracks.

Three U.S. banks collapsed in a matter of days. Credit Suisse, a 166-year-old storied Swiss lender, was teetering on the edge until the government orchestrated a bargain sale to rival USB. A $30 billion rescue of regional U.S. lender First Republic was unable to arrest the drop in its shares. U.S. banks are requesting loans from the Fed like it’s 2008, when the financial system all but collapsed. And liquidity in the Treasury market – basically the blood that keeps financial markets pumping – is drying up.

Before Silicon Valley Bank’s collapse, interest rate futures were putting the odds of an increase in rates – either 0.25 or 0.5 percentage point – on March 22 at 100%. The odds of no increase at all have shot up to as high as 45% on March 15 before falling to 30% early on March 20, with the balance of probability on a 0.25 percentage point hike.

Increasing rates at a moment like this would mean putting more pressure on a structure that’s already under a lot of stress. And if things take a turn for the worse, the Fed would likely have to do a quick U-turn, which would seriously damage the Fed’s credibility and ability to do its job.

Fed officials are right to worry about fighting inflation, but they also don’t want to light the fuse of a financial crisis, which could send the U.S. into a recession. And I doubt it would be a mild one, like the kind economists have been worried the Fed’s inflation fight could cause. Recessions sparked by financial crises tend to be deep and long – putting many millions out of work.

What would normally be a routine Fed meeting is shaping up to be a high-wire balancing act.

Alexander Kurov, Professor of Finance and Fred T. Tattersall Research Chair in Finance, West Virginia University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Simple ways to begin your morning

Simple ways to begin your morning

Ready, set, go. Just as you would set off at the starting line of a race, this hectic pace is how mornings begin for many men and women.

Instead of waking with dread to face another hectic morning, consider these tips for a healthier way to ease into your daily rituals. While these activities may require you to allow extra time, you may be pleased with the productive results.

Meditate. A practice that has been around for thousands of years may still be one of the best stress busters for hurried mornings. To start, find a place in your home that is free of noise and distraction. Practice sitting still, with eyes closed, and focus only on your breathing. Using deep, controlled breaths, try to steer your thoughts away from negative and stress-inducing thoughts.

Stretch. While the most health-conscious person may opt for a morning sweat-a-thon, working in some stretches can also be beneficial. When you awake, think about oft-used muscles and extend each one for 15-30 seconds.

Activate. Give your brain some fuel in the morning while also doing something nice for your mind. For example, journaling is a gentle way to ease into your morning and get your brain firing. If you can’t think of a topic, simply write down a few affirmations for the day, revisit a pleasant memory from your past or scribble down a goal for the week. Journaling can be an uplifting way to engage the mind and express gratitude for the day ahead.

Find more tips for starting your day on the right foot at eLivingToday.com.

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