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The existence of a new kind of magnetism has been confirmed

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Illustration of altermagnetism in a chemical compound


Illustration of altermagnetism in a chemical compound

Altermagnetism works differently from standard magnetism

Libor Šmejkal and Anna Birk Hellenes

A new kind of magnetism has been measured for the first time. Altermagnets, which contain a blend of properties from different classes of existing magnets, could be used to make high capacity and fast memory devices or new kinds of magnetic computers.

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Until the 20th century, there was thought to be only one kind of permanent magnet, a ferromagnet, the effects of which can be seen in objects with relatively strong external magnetic fields like fridge magnets or compass needles.

These fields are caused by the magnetic spins of the magnets’ electrons lining up in one direction.

But, in the 1930s, French physicist Louis Néel discovered another kind of magnetism, called antiferromagnetism, where the electrons’ spins are alternately up and down. Although antiferromagnets lack the external fields of ferromagnets, they do show interesting internal magnetic properties because of the alternating spins.

Then in 2019, researchers predicted a perplexing electric current in the crystal structure of certain antiferromagnets, called the anomalous Hall effect, which couldn’t be explained by the conventional theory of alternating spins. The current was moving without any external magnetic field.

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It seemed, when looking at a crystal in terms of sheets of spins, that a third kind of permanent magnetism might be responsible, which has been called altermagnetism. Altermagnets would look like antiferromagnets, but the sheets of spins would look the same when rotated from any angle. This would explain the Hall effect, but no one had seen the electronic signature of this structure itself, so scientists were unsure whether it was definitely a new kind of magnetism.

Now, Juraj Krempaský at the Paul Scherrer Institute in Villigen, Switzerland, and his colleagues have confirmed the existence of an altermagnet by measuring the electron structure in a crystal, manganese telluride, that was previously thought to be antiferromagnetic.

To do this, they gauged how light bounced off manganese telluride to find the energies and speeds of the electrons inside the crystal. After mapping out these electrons, they were found to almost exactly match the predictions given by simulations for an altermagnetic material.

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The electrons seemed to be split into two groups, which allows them more movement inside the crystal and is the source of the unusual altermagnetic properties. “This gave direct evidence that we can talk about altermagnets and that they behave exactly as predicted by theory,” says Krempaský.

This electron grouping seems to come from the atoms of tellurium, which is non-magnetic, in the crystal structure, which separate the magnetic charges of the manganese into their own planes and allow the unusual rotational symmetry.

“It’s really nice verification that these materials do exist,” says Richard Evans at the University of York, UK. As well as the electrons in altermagnets being freer to move than those in antiferromagnets, this new type of magnet also doesn’t have external magnetic fields like in ferromagnets, says Evans, so you can use them to make magnetic devices that don’t interfere with each other.

The property could boost the storage on computer hard drives, because commercial devices contain ferromagnetic material that is so tightly packed that the material’s external magnetic fields start to see interference – altermagnets could be packed more densely.

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The magnets could even lead to spintronic computers that use magnetic spin instead of current to perform their measurements and calculations, says Joseph Barker at the University of Leeds, UK, combining memory and computer chips into one device. “It maybe gives more hope to the idea that we could make spintronic devices become a reality,” says Barker.

Article amended on 15 February 2024

We have corrected when Louis Néel discovered antiferromagnetism and the name of the crystal studied to confirm the existence of altermagnetism.

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Over $2.8 billion bet on bitcoin topping $90,000 as it hits all-time high

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Over $2.8 billion bet on bitcoin topping $90,000 as it hits all-time high


Jakub Porzycki | Nurphoto | Getty Images

Bitcoin reached a fresh all-time high near $81,000 and futures premiums soared, in a clear sign that investors believe the record-run in the world’s largest cryptocurrency is poised for even more gains on the back of U.S. elections that saw a swell of pro-crypto candidates win office.

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Open interest in bitcoin’s price surpassing $90,000 rose to more than $2.8 billion on the popular Deribit derivatives exchange, one of a few crypto native platforms that offers futures trading. Deribit encompasses most of the offshore options market.

“The options market’s bias is heavily toward continued momentum. Call options trade at a premium to puts, and open interest in out-of-the-money calls has grown,” Vetle Lunde, head of research at K33 Research, told CNBC.

A call option gives the buyer the right to buy shares of an underlying asset at a certain price for a specified period of time. Buying a call option is a bet the asset price will move higher. Buying a put option is a bet the asset price will fall.

The CME derivates exchange offers bitcoin futures contracts and is a popular way for institutions in the U.S. to make bets on the future price of bitcoin. Velde told CNBC that on Friday CME premiums for ether and bitcoin averaged 14.5% and 14%, respectively. Ahead of the election, Velde says these premiums sat at 7%, and had spent a majority of the past half year hovering slightly below 10%.

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“The recent surge is a meaningful deviation higher emphasizing the bullish flows of late,” he added, noting that yields more or less stabilized well into the double digits after the election became clear.

“Alongside the growth in leverage, we saw the first meaningful example of growing yields in offshore derivatives, indicative of the move being led by determined risk-takers positioning for further upside,” said Velde.

The early innings of bitcoin’s push higher coincided with substantial growth in open interest in perpetual swaps, or contracts that allow buyers to speculate on where they think prices are headed without a set expiration date.

But liquidity in crypto markets on weekends is typically poorer than during weekdays, as neither CME futures nor ETFs are open to trade, so moves thus tend to overreact and substantially retrace once these markets open again, according to Velde.

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Bitcoin could hit $100k before inauguration if Trump delivers on pro-crypto campaign pledges

President-elect Donald Trump promised on the campaign trail to turn the United States into the “crypto capital of the planet.” His multiple pledges to the crypto community included launching a national crypto stockpile with the more than $16 billion in bitcoin the U.S. government has amassed through asset seizures, as well as slashing interest rates. The easing of monetary policy typically dovetails with a surge in crypto prices since it makes it cheaper to borrow money.

The Federal Reserve, which guides the country’s monetary policy, sets the benchmark rate. It also, by design, operates independently from the White House. On Thursday, the Fed approved its second consecutive interest rate cut.

On the back of election results and the Fed’s unanimous vote to again slash the benchmark rate, the crypto market broadly surged into the weekend. Ether eclipsed bitcoin’s rise, up 30% in the last seven days, and solana’s market cap topped $100 billion on Sunday.

The total market cap of all spot bitcoin ETFs is now above $80 billion, and in the last three trading days alone, the spot funds collectively added $2.3 billion.

How crypto and fintech may perform under the second Trump administration

Within fintech, companies tied to crypto were some of the top performers, after candidates funded by the crypto industry won races up and down the ballot.

Coinbase shares jumped 48% for the week, their strongest performance since January 2023. Coinbase was one of the top corporate donors in the election cycle, giving more than $75 million to Fairshake and its affiliate PACs, including a fresh pledge of $25 million to support the pro-crypto super PAC in the 2026 midterms.

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Trump has vowed to oust SEC Chair Gary Gensler, which potentially bodes well for companies like Coinbase fighting the regulator in court over alleged securities offenses.

“Tuesday night was certainly a big night for crypto and the crypto voter,” Coinbase’s chief legal officer Paul Grewal said in an interview. “We’re going to have the most pro-crypto Congress ever, and Coinbase has played some part in all of that.”

Robinhood, which allows users to buy and sell a number of digital currencies, rose 27% for the week. The online brokerage received a Wells Notice from the SEC in May, a move that often precedes formal charges.

Robinhood’s general manager for its crypto unit told CNBC that the goal at Robinhood is to be able to work within the administration.

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“If you think about crypto, it’s a very fast-moving pace. It’s complicated, it was made by engineers, for engineers,” said Johann Kerbrat, the Vice President and General Manager of Robinhood Crypto. “We want to help policymakers to understand it and help them drive the right protections for the customers.”

Robinhood Crypto general manager reacts to recent bitcoin rally



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How to see the Taurid Meteor Shower

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How to see the Taurid Meteor Shower


Viewing the Taurids may be affected by the illumination of the Moon, which could obscure some of the fainter meteors. The Moon will be in a waxing gibbous phase – going from half moon to full moon.

Plus, as we have seen recently, it is hard to see anything in the sky if there is a blanket of low cloud. However, there could be some timely changes in cloud amounts at the time of peak viewing.

A weather front crossing the UK on Sunday will bring a change in air mass. Even though an area of high pressure will build again, it may not contain as much cloud.

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It is possible that the clouds will part on Monday night and give us a better chance of seeing some spectacular meteor displays.

Keep across your local forecast on the BBC Weather website or app.



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Fintechs Upstart and Toast soar on earnings

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Fintechs Upstart and Toast soar on earnings


Chris Comparato, CEO, the Toast, Inc. IPO at the New York Stock Exchange, on September 22, 2021.

Source: NYSE

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Upstart, which uses artificial intelligence to inform online lending decisions, soared 46% on Friday, its best day in over three years. Toast, which sells payments technology to restaurants, jumped 14%, closing at its highest since 2021.

Both companies reported better-than-expected results, sparking the rallies.

Upstart’s revenue jumped 20% in the third quarter to $162 million, easily beating analyst estimates. CEO David Girouard said on the company’s earnings call that,we’re in growth mode.”

Toast is still well off its pandemic highs of 2021, but the stock has now more than doubled this year. The company’s adjusted earnings forecast of $90 million to $100 million for the current quarter sailed past estimates.

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The two stocks were part of a huge rally on Wall Street this week that followed Donald Trump’s election victory on Tuesday night. All three major indexes closed at records, with the tech-heavy Nasdaq finishing the week up 5.7%, its second-best week of the year.

Within fintech, companies tied to crypto were some of the top performers, after candidates funded by the crypto industry won races up and down the ballot.

Coinbase shares jumped 48% for the week, their strongest performance since January 2023. Coinbase was one of the top corporate donors in the election cycle, giving more than $75 million to Fairshake and its affiliate PACs, including a fresh pledge of $25 million to support the pro-crypto super PAC in the 2026 midterms.

Trump has vowed to oust SEC Chair Gary Gensler, which potentially bodes well for companies like Coinbase fighting the regulator in court over alleged securities offenses.

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Robinhood, which allows users to buy and sell a number of digital currencies, rose 27% for the week. The online brokerage received a Wells Notice from the SEC in May, a move that often precedes formal charges.

Bitcoin hit a new intraday high above $77,300, ending the week 11% higher. Ether, solana, and dogecoin outpaced bitcoin’s gains.

Not all fintechs rallied.

Block, the parent company of Square, reported third-quarter revenue on Thursday that trailed Wall Street’s expectations, leading to a slight drop in the stock on Friday. Shares of Jack Dorsey’s company underperformed the boarder tech market for the week, rising 3.3%.

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Affirm, the provider of buy now, pay later loans, beat on the top and bottom line, but the stock still dropped 4.7% on Friday, leaving it slightly ahead of the Nasdaq for the week.

WATCH: Robinhood Crypto general manager reacts to bitcoin rally

Robinhood Crypto general manager reacts to recent bitcoin rally



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Why did the UK’s first satellite end up thousands of miles from where it should have been?

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Why did the UK's first satellite end up thousands of miles from where it should have been?


BBC/Gerry Fletcher Artist's rendering of the Skynet-1A satelliteBBC/Gerry Fletcher

Artwork: The half-tonne Skynet-1A satellite was launched in November 1969

Someone moved the UK’s oldest satellite and there appears to be no record of exactly who, when or why.

Launched in 1969, just a few months after humans first set foot on the Moon, Skynet-1A was put high above Africa’s east coast to relay communications for British forces.

When the spacecraft ceased working a few years later, gravity might have been expected to pull it even further to the east, out over the Indian Ocean.

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But today, curiously, Skynet-1A is actually half a planet away, in a position 22,369 miles (36,000km) above the Americas.

Orbital mechanics mean it’s unlikely the half-tonne military spacecraft simply drifted to its current location.

Almost certainly, it was commanded to fire its thrusters in the mid-1970s to take it westwards. The question is who that was and with what authority and purpose?

It’s intriguing that key information about a once vital national security asset can just evaporate. But, fascination aside, you might also reasonably ask why it still matters. After all, we’re talking about some discarded space junk from 50 years ago.

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“It’s still relevant because whoever did move Skynet-1A did us few favours,” says space consultant Dr Stuart Eves.

“It’s now in what we call a ‘gravity well’ at 105 degrees West longitude, wandering backwards and forwards like a marble at the bottom of a bowl. And unfortunately this brings it close to other satellite traffic on a regular basis.

“Because it’s dead, the risk is it might bump into something, and because it’s ‘our’ satellite we’re still responsible for it,” he explains.

BBC/Gerry Fletcher Map of the world showing the original location of Skynet 1A over East Africa, as well as the two gravity wells, one at 75 degrees east, which is where the satellite was expected to go, and one at 105 degrees west, which is where it is now.BBC/Gerry Fletcher

If a satellite died at 40E it would drift to the nearest gravity well, which is 75E.

Dr Eves has looked through old satellite catalogues, the National Archives and spoken to satellite experts worldwide, but he can find no clues to the end-of-life behaviour of Britain’s oldest spacecraft.

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It might be tempting to reach for a conspiracy theory or two, not least because it’s hard to hear the name “Skynet” without thinking of the malevolent, self-aware artificial intelligence (AI) system in The Terminator movie franchise.

But there’s no connection other than the name and, in any case, real life is always more prosaic.

What we do know is that Skynet-1A was manufactured in the US by the now defunct Philco Ford aerospace company and put in space by a US Air Force Delta rocket.

“The first Skynet satellite revolutionised UK telecommunications capacity, permitting London to securely communicate with British forces as far away as Singapore. However, from a technological standpoint, Skynet-1A was more American than British since the United States both built and launched it,” remarked Dr Aaron Bateman in a recent paper on the history of the Skynet programme, which is now on its fifth generation.

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This view is confirmed by Graham Davison who flew Skynet-1A in the early 70s from its UK operations centre at RAF Oakhanger in Hampshire.

“The Americans originally controlled the satellite in orbit. They tested all of our software against theirs, before then eventually handing over control to the RAF,” the long-retired engineer told me.

“In essence, there was dual control, but when or why Skynet-1A might have been handed back to the Americans, which seems likely – I’m afraid I can’t remember,” says Mr Davison, who is now in his 80s.

Sunnyvale Heritage Park Museum A rectangular blue building surrounded by outbuildings and roads. Two large satellite dishes can also be seen.Sunnyvale Heritage Park Museum

Could the command to move Skynet-1A have come from the US Air Force’s ‘Blue Cube’?

Rachel Hill, a PhD student from University College London, has also been scouring the National Archives.

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Her readings have led her to one very reasonable possibility.

“A Skynet team from Oakhanger would go to the USAF satellite facility in Sunnyvale (colloquially known as the Blue Cube) and operate Skynet during ‘Oakout’. This was when control was temporarily transferred to the US while Oakhanger was down for essential maintenance. Perhaps the move could have happened then?” Ms Hill speculated.

The official, though incomplete, logs of Skynet-1A’s status suggest final commanding was left in the hands of the Americans when Oakhanger lost sight of the satellite in June 1977.

But however Skynet-1A then got shifted to its present position, it was ultimately allowed to die in an awkward place when really it should have been put in an “orbital graveyard”.

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This refers to a region even higher in the sky where old space junk runs zero risk of running into active telecommunications satellites.

Graveyarding is now standard practice, but back in the 1970s no-one gave much thought to space sustainability.

Astroscale Astroscale engineers and a prototype robotic arm for space debris mitigationAstroscale

British engineers are developing technologies to snare defunct satellites in low orbits

Attitudes have since changed because the space domain is getting congested.

At 105 degrees West longitude, an active satellite might see a piece of junk come within 50km of its position up to four times a day.

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That might sound like they’re nowhere near each other, but at the velocities these defunct objects move it’s starting to get a little too close for comfort.

The Ministry of Defence said Skynet-1A was constantly monitored by the UK’s National Space Operations Centre. Other satellite operators are informed if there’s likely to be a particularly close conjunction, in case they need to take evasive action.

Northrop Grumman Northrop Grumman's Mission Extension Vehicle-1 approaches Intelsat-901Northrop Grumman

The Americans have already shown it’s possible to grab a high-orbiting satellite

Ultimately, though, the British government may have to think about removing the old satellite to a safer location.

Technologies are being developed to grab junk left in space.

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Already, the UK Space Agency is funding efforts to do this at lower altitudes, and the Americans and the Chinese have shown it’s possible to snare ageing hardware even in the kind of high orbit occupied by Skynet-1A.

“Pieces of space junk are like ticking time bombs,” observed Moriba Jah, a professor of aerospace engineering at the University of Texas at Austin.

“We need to avoid what I call super-spreader events. When these things explode or something collides with them, it generates thousands of pieces of debris that then become a hazard to something else that we care about.”



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Jack Dorsey dramatically shutters Block’s TBD crypto unit

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Jack Dorsey dramatically shutters Block's TBD crypto unit


Jack Dorsey, co-founder of Twitter Inc., speaks during the Bitcoin 2021 conference in Miami, Florida, U.S., on Friday, June 4, 2021.

Eva Marie Uzcategui | Bloomberg | Getty Images

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During the crypto-crazed summer of 2021, when memecoins like dogecoin and Shiba Inu were rocketing alongside bitcoin and ethereum, Square founder Jack Dorsey announced that his payments company was starting a new business unit, with the goal of “making it easy to create non-custodial, permissionless, and decentralized financial services.”

“Our primary focus is #Bitcoin,” Dorsey proclaimed on Twitter. The name of the business unit would be TBD.

In December of that year, Dorsey went a step further, changing the name of Square Inc. to Block, a reference, he said, to a number of things, including blockchain, the technology underpinning bitcoin. The Square Crypto business became known as Spiral.

Three years later, Dorsey is in retreat.

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On Block‘s third-quarter earnings call on Thursday, CFO Amrita Ahuja said Block has “made some recent decisions with respect to some of our emerging initiatives” and is “winding down our TBD efforts.”

Block continues to own a hefty amount of bitcoin on its balance sheet, with the current value of its holdings swelling to $630 million. And the company said it will be investing in a bitcoin mining initiative as well as Bitkey, its bitcoin wallet, while continuing to allow users to buy bitcoin through Cash App.

It’s a notable change of tune.

TBD was designed to be Block’s platform for developers. Block called it Web5 and said the mission was to create a more decentralized, secure and private internet. Dorsey said in a tweet in mid-2022 that Web5 “will likely be our most important contribution to the internet.”

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Square’s five-year stock chart

But Wall Street’s view on crypto was starting to sour dramatically. With inflation soaring in 2022 and interest rates on the rise, shareholders demanded quicker returns on their investments. After peaking in 2021, Block shares lost more than 80% of their value before bottoming in October of last year.

Block said in late 2023 that it would cut its headcount — then about 13,000 staffers — by as much as 1,000 by the end of 2024. Fortune reported that Block laid off employees at TBD in recent weeks. And in the third-quarter shareholder letter, Block said it was “scaling back” its investment in Tidal, the music-streaming service founded by Jay-Z, after spending about $300 million on a majority stake in the business in 2021. Tidal was part of TBD.

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Dorsey was asked by an analyst on Thursday’s call about the company’s current bitcoin strategy.

“What we’re focused on in terms of our strategy overall on bitcoin is making it more accessible, making sure that more people can access bitcoin, buy, sell it, obviously, but also send it peer-to-peer,” Dorsey said.

Dorsey added that he wants “the internet to have a native currency,” because that would allow Block to move money faster and offer Cash App and other products in more markets.

A Block spokesperson reiterated the company’s public statement and pointed to Dorsey’s comments from the earnings call.

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What’s become clear is that Dorsey can only do so much with crypto while trying to appease a more discerning Wall Street. Shares of Block were down about 1% at market close on Friday, after the company reported revenue that trailed estimates and issued weaker gross profit guidance than some analysts were expecting.

In his 1,400-word letter to shareholders, Dorsey focused entirely on the company’s lending offerings for small businesses. A significant chunk of that is the buy now, pay later product from Afterpay, which Block acquired for $29 billion in 2021.

Dorsey didn’t mention crypto or bitcoin once.

WATCH: Block and Affirm slide on earnings

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Block and Affirm slide on earnings



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Tesla was the top ‘Trump Trade’ of the week, along with some energy and financial stocks

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Tesla was the top ‘Trump Trade’ of the week, along with some energy and financial stocks




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