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Inside the House GOP effort to keep weapons flowing to Ukraine

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Washington
CNN
 — 

After House Minority Leader Kevin McCarthy suggested last week that Republicans might pull back funding for Ukraine next year if they take the majority, the GOP leader has worked behind the scenes to reassure national security leaders in his conference that he wasn’t planning to abandon Ukraine aid and was just calling for greater oversight of any federal dollars, sources told CNN.

McCarthy told key Republican national security committee members – some of whom reached out to McCarthy – that his comments that Ukraine wouldn’t get a “blank check” in a Republican majority were being taken out of context, the sources said. Rather, McCarthy told his members he was simply saying that a GOP-led House would not automatically rubber-stamp a request from the administration for additional Ukraine aid.

“McCarthy was not saying, ‘We wouldn’t spend money.’ McCarthy was saying, ‘We’re gonna be accountable to the taxpayer for every dollar we spend,’” one GOP lawmaker familiar with McCarthy’s thinking told CNN. “A ‘blank check’ means that people get whatever they ask for. What we’re saying is there’s going to be some thought, there’s going to be accountability, and taxpayer dollars are going to be used appropriately.”

McCarthy’s effort to soothe the House’s senior defense hawks, which has not been previously reported, underscores the fine line the aspiring speaker is walking on foreign policy as the war in Ukraine appears poised to grind into a second year. But it also offers a preview of the types of policy and political battles to come between the establishment and pro-Trump wings of the GOP, presenting a tricky balancing act — and potential headaches — for Republican leaders in a House majority.

Ukraine has led to messy politics for Democrats as well. On Monday, Progressive Caucus leader Rep. Pramila Jayapal of Washington state abruptly withdrew a letter pushing the Biden administration to pursue diplomacy in Russia’s war with Ukraine, an about-face following furious internal backlash from Democrats.

Liberal Democrats abruptly withdraw letter on Ukraine policy amid anger

GOP sources told CNN they believe that only a small faction of Republican lawmakers — the midterm elections will determine how many — are opposed to funding Ukraine’s battlefield efforts. What’s more likely to likely face cuts under a GOP majority, sources said, is the economic assistance and other non-military aid going to Ukraine, like the aid money going to the United Nations to help Ukraine rebuild its country and the money going to USAID to support Ukraine’s budget.

If Republicans win back the House, GOP sources say they are likely to ramp up overall oversight of the billions of dollars in aid going to Ukraine, such as examining end-use tracking of weapons. CNN has previously reported that the Biden administration doesn’t have perfect visibility into how or where US-provided weapons are used once they cross the border into Ukraine.

Still, senior congressional Republicans who support robustly funding Ukraine’s war are watching warily as some more isolationist-minded colleagues have become increasingly vocal in recent weeks that they will heavily scrutinize – if not outright oppose – US money for Ukraine.

Fifty-seven Republicans in the House and 11 in the Senate voted against the $40 billion Ukraine aid bill in May. Some vocal GOP opponents like Reps. Marjorie Taylor Greene of Georgia and Chip Roy of Texas jumped on McCarthy’s recent comments to argue that a Republican majority should scale back aid to Ukraine.

The anti-aid crowd also has influential voices like Fox’s Tucker Carlson and Donald Trump Jr. who have advocated for cutting off aid to Ukraine altogether.

“They’re strong. Amongst Republicans, I call it the ‘Tucker Carlson’ effect,” the lawmaker said of House GOP skeptics. “I love Tucker on other issues, but he’s wrong on this. He’s listening to Russia disinformation. And he’s creating problems for us in our districts.”

McCarthy can’t afford to alienate or ignore the noisy skeptics in his conference who have raised concerns about indefinitely funding Ukraine’s war against Russia – whose votes he will need to become speaker, especially if Republicans win a narrow majority.

“McCarthy cracked the door open here. He is leaning more towards our direction of pulling back. You also have Tucker Carlson and Laura Ingraham banging the drum on this,” said a source familiar with the ongoing discussions about Ukraine aid who favors tighter purse strings.

A McCarthy spokesman did not respond to requests for comment.

Last week, McCarthy told Punchbowl News, “I think people are going to be sitting in a recession, and they’re not going to write a blank check to Ukraine.”

The comments prompted frantic outreach on Capitol Hill from Ukrainians and European allies alike, sources told CNN, intensifying long-running concerns that a Republican majority in Congress threatens to hamper US support for Ukraine’s war against Russia.

They also led some GOP national security hawks to begin planning a campaign for after the midterm election to ensure that the US doesn’t abandon Ukraine. That includes preparing a combination of education for their new and skeptical colleagues as well as examining ways to increase oversight of where the money and weapons are going inside Ukraine.

To help convince skeptics, Republicans are looking to tap former Trump administration national security leaders as expert voices – rather than Biden administration officials. Some of the voices that Republicans are considering bringing in to speak to new members include former Secretary of State Mike Pompeo and former Deputy National Security Adviser Matthew Pottinger, sources said.

“They need to hear from people they trust. The administration isn’t necessarily the best messenger for this,” said one GOP congressional aide.

They’re also planning to hold briefings from Republican think tanks with conservative bona fides like the Heritage Foundation, congressional trips to the region and direct engagement with Ukrainian and European officials as part of an education campaign.

“I don’t think the issue is one of lack of support of aid from Ukraine. It’s a signaling that Republicans do things differently,” Rep. Mike Turner, an Ohio Republican in line to chair the House Intelligence Committee next year, said in an interview with CNN.

Turner, who just returned from a bipartisan congressional meeting with Ukrainian President Volodymyr Zelensky in Ukraine, argued the bills that Democrats passed this year – such as a $40 billion aid package in May – included extraneous funding that he criticized as a “bloated bureaucracy,” such as money that went to the UN.

“Kevin McCarthy supports providing weapons systems to Ukraine to continue to win on the battlefield,” Turner said in a roundtable with reporters on Monday.

Despite confidence among GOP hawks that they have the upper hand over the caucus’ more isolationist wing, lawmakers are beginning to lay the groundwork to convince new members in particular that the military support is vital spending.

Congressional Democrats on national security committees told CNN that McCarthy’s comments didn’t raise major alarm bells – yet – as they still believe there’s significant support for Ukraine among their Republican colleagues. One Democrat noted that Senate GOP Leader Mitch McConnell is a stalwart supporter of funding Ukraine’s war – and the Senate often gets its way in funding fights.

“There’s the Reagan block and there’s the Trump block. And the Reagan block wants to help,” said another House Democrat who works on national security issues. McCarthy, the Democrat said, was “signaling that he’s going to have resistance and it’s not going to be easy.”

In the House, the pro-Ukraine effort is likely to be led by the “three Mikes” poised to become committee chairmen: Turner of Ohio on Intelligence, Mike McCaul of Texas on Foreign Affairs, and Mike Rogers of Alabama on Armed Services.

Another key voice will be Rep. Kay Granger of Texas, a defense hawk who is expected to become House Appropriations chairwoman in a Republican majority.

If he becomes chairman of the House Foreign Affairs Committee, McCaul is considering holding his first hearing next year on Russian war crimes, according to one congressional source, to hammer home the egregiousness of Russia’s actions in Ukraine.

“We’ve got to give them what they need. The Ukrainians, when we give them what they need, they win,” McCaul said on Bloomberg TV last week. “I do think you have broad bipartisan support for what’s happening in Ukraine, but I think you’ll see if we get the majority, more oversight and accountability in terms of the funding and where the money is going.”

The defense hawks are expected to make the case that the war with Russia goes beyond Europe. They argue that the US needs Ukraine to win in order to deter China from invading Taiwan, for instance. One senior Republican noted that Iranian drones now being used on the battlefield show how the war extends far beyond Ukraine’s borders.

The Ukrainians are also likely to make their own case directly to Congress. Ukrainian legislators and other top officials have held meetings with their American counterparts since the war began, telling US lawmakers that it is cheaper to invest in Ukrainian defense now than to defend Europe against wide-ranging Russian aggression later.

Ukraine skeptics both in Congress and on the campaign trail – along with influential outside voices – are preparing to ramp up their own campaign to try to curtail or outright stop the flow of US dollars to Ukraine.

Republican criticism of funding Ukraine has largely focused on the high costs of prolonging the war, as well as concerns about corruption in Ukraine and the need to devote more resources to domestic challenges. Earlier this month, the House Freedom Caucus wrote to McCarthy urging him to stand up a special inspector general on US involvement in Ukraine.

Greene, a far-right Georgia Republican, posted a video on Twitter last month saying, “There is a country’s border that he (Biden) cares about and it is not this country’s border, it is Ukraine’s border. I believe our American tax dollars need to be used only for our country while we have so many problems, security crises.”

After McCarthy’s comments last week, Rep. Jim Banks, an Indiana Republican who is seeking a House leadership post next year, tweeted, “A Republican-led House will put the needs of America first. We cannot continue with unlimited spending for any foreign nation while our people are struggling to get by here at home.”

The Senate GOP conference could also soon have new members who have been vocal opposing the aid, such as J.D. Vance, the Senate GOP nominee in Ohio. “I think we’re at the point where we’ve given enough money in Ukraine, I really do,” Vance told local Ohio television station 13abc last month.

But McConnell also weighed in last week with a statement urging the Biden administration and US allies to “be quicker and more proactive to get Ukraine the aid they need” – comments that were in stark contrast to McCarthy’s statement and a sign that McConnell expects Senate Republicans to continue to support Ukraine’s war.

Dan Caldwell, vice president of foreign policy at Stand Together, a conservative non-profit that opposes open-ended spending in Ukraine, said those advocating for scaling back support to Ukraine are also gearing up to make their voices heard with new members in what’s expected to be a Republican-controlled Congress.

“During the first few weeks of the new Congress, new members will have a lot of people trying to convince them to not keep their campaign promises to oppose interventionist policies in Ukraine,” Caldwell said. “Our community will make the argument to these members that not only is pursuing a more realist approach to Ukraine good policy, it is also good politics – especially considering domestic economic challenges and more important foreign policy priorities in other parts of the world.”

The looming fight over Ukraine aid could come even before Republicans take control of Congress next year, as the Biden administration is considering pushing through another major Ukrainian assistance package before the end of 2022, administration officials told CNN. So far this year, Congress has approved more than $65 billion in aid toward Ukraine. While the administration believes that Republicans are unlikely to completely curtail support for Ukraine, they see value in locking in support now before things could get more challenging.

“End of the year funding in Washington is going to be the wild, wild West of spending, especially if Republicans win the House,” Turner told reporters Monday, adding that Republicans could oppose a bill with extraneous items attached.

Regardless of what it can get approved during the lame-duck session, the Biden administration will likely have to come back to Congress at some point next year to ask for money.

While there is an acknowledgment that oversight will have to ramp up when reconstruction in Ukraine begins – which could be needed even before the war ends due to just how much help Ukraine will need – many congressional aides and administration officials believe that additional layers are not necessary at this time.

Estonian Defense Minister Hanno Pevkur argued there already is clear accountability when it comes to weapons getting onto the battlefield.

“I understand their position to have more accountability. I also have information from (Joint Chiefs Chairman) Gen. (Mark) Milley, who said to me that there is more of an accountability as ever, regarding the help sent to Ukraine, because they even have a barcode system to track basically each shipment which was sent to Ukraine,” he said. “I believe this is exactly what also Republicans want to hear that yes, there is accountability.”

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Science

After Years of Searching, Physicists Observe Electrons Flow Into Fluid-Like Whirlpools

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For the first time, physicists have witnessed something incredibly exciting: electrons forming whirlpools just like a fluid.

This behavior is one that scientists have long predicted, but never observed before. And it could be the key to developing more efficient and faster next-generation electronics.

 

“Electron vortices are expected in theory, but there’s been no direct proof, and seeing is believing,” says one of the researchers behind the new study, physicist Leonid Levitov from MIT. 

“Now we’ve seen it, and it’s a clear signature of being in this new regime, where electrons behave as a fluid, not as individual particles.”

While electrons flowing in a vortex may not sound that groundbreaking, this a big deal because flowing like a fluid results in more energy being delivered to the end point, instead of being lost en route while electrons are jostled around by things such as impurities in the material or vibrations in atoms.

“We know when electrons go in a fluid state, [energy] dissipation drops, and that’s of interest in trying to design low-power electronics,” says Levitov. “This new observation is another step in that direction.”

The work was a joint experiment between MIT, the Weizmann Institute for Science in Israel, and the University of Colorado at Denver.

Of course, we already know that electrons can bounce off each other and flow without resistance in superconductors, but this is the result of the formation of something known as ‘Cooper pairs’, and isn’t a true example of electrons collectively flowing like a fluid.

 

Take water, for example. Water molecules are individual particles, but they travel as one according to the principles of fluid dynamics, carrying each other across a surface, making streams and whirlpools as they go.

An electric current should essentially be able to do the same, but any collective behavior of electrons is usually overridden by impurities and vibrations in normal metals and even semiconductors. These ‘distractions’ knock electrons around as it travels and stops them from exhibiting fluid-like behavior. 

It’s long been predicted that within special materials at near-zero temperatures, these interferences should disappear allowing the electrons to move like a fluid… but the problem was no one had actually been able to prove this was the case, until now.

There are two fundamental features of a fluid: linear flow, where separate particles all flow in parallel as one; and the formation of vortices and eddies.

The first was observed by Levitov and colleagues at the University of Manchester back in 2017 using graphene. In atom-thin sheets of carbon, Levitov and his team showed that an electrical current could flow through a pinch point like fluid, rather than like grains of sand.

 

But no one had seen the second feature. “The most striking and ubiquitous feature in the flow of regular fluids, the formation of vortices and turbulence, has not yet been observed in electron fluids despite numerous theoretical predictions,” the researchers write.

To figure this out, the team took pure, single crystals of an ultra-clean material known as tungsten ditelluride (WTe2) and sliced off single-atom-thin flakes. 

They then etched a pattern into a central channel with a circular chamber on either side, creating a ‘maze’ for an electrical current to run through. They etched the same pattern on flakes of gold, which doesn’t have the same ultra-clean properties as the tungsten ditelluride and therefore acted as a control. 

(Aharon-Steinberg et al., Nature, 2022)

Above: The diagram on the left shows how electrons flowed in the experiment in gold (Au) flakes. The image on the right shows a simulation of how they’d expect fluid-like electrons to behave.

After cooling the material to around -269 degrees Celsius (4.5 Kelvin or -451.57 Fahrenheit) they ran an electrical current through it and measured the flow at specific points throughout the material, to map how the electrons were flowing.

 

In the gold flakes, the electrons flowed through the maze without changing direction, even when the current had passed through each side chamber before coming back to the main current.

In contrast, within the tungsten ditelluride, the electrons flowed through the channel and then swirled into each side chamber creating whirlpools, before flowing back into the main channel – like you’d expect a fluid to do.

“We observed a change in the flow direction in the chambers, where the flow direction reversed the direction as compared to that in the central strip,” says Levitov.

“That is a very striking thing, and it is the same physics as that in ordinary fluids, but happening with electrons on the nanoscale. That’s a clear signature of electrons being in a fluid-like regime.”

(Aharon-Steinberg et al., Nature, 2022)

Above: The column on the left shows how the electrons flowed through tungsten ditelluride (WTe2) compared to the hydrodynamic simulations in the left column. 

Of course, this experiment was done at ultra-cold temperatures with a specialized material – it’s not something that’ll be happening in your home gadgets any time soon. There were also size constraints on the chambers and the middle channel.

But this is the “first direct visualization of swirling vortices in an electric current” as the press release explains. Not only is this confirmation that electrons can behave as a fluid, the advance could also help engineers to better understand how to harness this potential in their devices. 

The research has been published in Nature.

 

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Science

Hubble Space Telescope spots streams of star formation flowing between galaxies

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Stars from colliding galaxies flow together in a newly upgraded image from NASA’s venerable space telescope.

The Hubble Space Telescope has been hard at work for more than three decades, and scientists never lose their fascination with the observatory’s vast archives. Take, for example, this “river of star formation,” as NASA officials termed it in a statement released on Wednesday (May 17), takes place in an intersection of four dwarf galaxies within the Hickson Compact Group 31 (HCG 31) of galaxies.

The image was first released in 2010 and was re-envisioned to showcase star-forming regions. Blue in the image represents visible blue light, in which several hot, young blue stars are shining, particularly in a pair of colliding dwarf galaxies collectively called galaxy NGC 1741 (top-right of center). Red shows off light in the near-infrared.

Related: The best Hubble Space Telescope images of all time!

“Another dwarf, cigar-shaped galaxy to [NGC 1741]’s right joins their dance with a thin, blue stream of stars that connects the trio,” NASA said. A fourth member, HGC 31, is visible at bottom left. There’s also a bright star in the way of the quartet galaxies, which you can see in the center of the image. 

Hubble has been imaging galaxies in high-detail for a generation, and numerous images released in recent weeks have focused on colliding galaxies. For example, in February the program released a pair of galaxies known as Arp 298, interacting 200 million light-years from Earth in the constellation Pegasus.

Arp 298 is also one of the first science targets of the new James Webb Space Telescope’s observations starting in summer 2022, Hubble officials said at the time. The $10 billion observatory is in its final weeks of commissioning and can render sharp images in many configurations; it will soon be assessed in hotter and colder conditions and for closer solar system objects.

Hubble will assist Webb for a few years in the newer observatory’s major task, which is to understand the evolution of the universe. Galaxies that were formed near the beginning of the universe will be studied, to chart how that group was different than the galaxies of today. 

One notable difference from the beginning of our universe’s history is the lack of heavier elements, and the relative abundance of hydrogen and helium. But charting the change of galaxies and shifts in dark matter, which cannot be sensed directly but seen through their influence on nearby objects, will be among Webb’s set of work.

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom or Facebook. 



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World

Ukraine Reduced Russian Gas Flowing to Europe Through Key Pipeline

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Ukraine reduced flows of Russian natural gas through its territory to Europe, sending prices higher amid the continent’s still-precarious reliance on Russian fossil fuels.

Within hours, though, enough gas was moving through an alternative route that prices fell back down again, ending essentially flat on the day.

The continued flow suggested some gas had been rerouted to travel through a separate pipeline, analysts and traders said. It was unclear what actions the Russian and Ukrainian sides took in the episode, but the quick rerouting demonstrated the country’s energy-grid flexibility despite the violence of the battlefield.

The reworked flows partly offset any lost exports to Europe. They also enabled Russia to continue piping its gas to its biggest customer, and collecting much-need payments for that gas. Ukraine benefited, too: Kyiv continues to pocket millions of dollars a month in transit fees that Moscow has paid it through the course of the war.

European gas prices leapt early in the day when Ukraine’s gas-transport company said it was shutting down a portion of the gas that travels across its territory from Russia to Europe. The company that runs Ukraine’s pipeline network halted the flow of gas through a major entry point in the east of the country Wednesday, blaming interference by Russian troops with critical gas infrastructure.

The border crossing accounts for a third of Russian gas exports through Ukraine to Europe and feeds 3% of the European Union’s overall gas consumption. An increase in flows of Russian gas through a separate section of pipeline in Ukraine-controlled territory near the city of Sumy partially offset the stoppage, limiting the rise in prices.

Europe has been shoring up its energy supplies ahead of a planned EU-wide embargo on Russian oil, being hashed out this week. Some member states, especially Germany, have also scrambled to find alternative supplies of gas amid the threat of a potential severing of exports by Moscow. Despite these moves, Europe is still heavily reliant on Russian gas, a slug of which flows through Ukraine. That gas had kept moving since the Feb. 24 invasion despite the raging conflict.

Ukrainian energy officials say Russia appears to have avoided deliberate strikes on pipelines that bring revenue into Russia’s bruised economy, though extensive damage to Ukraine’s domestic gas network left millions of residents without fuel. Ukraine, for its part, earns transit fees from Moscow for shuttling Russian gas to customers in Europe.

Wednesday’s cutoff at the Sokhranivka entry point, on the border between the Luhansk region of Donbas and Russia, marked the biggest interruption of gas supplies to date. It came as Russia continued to pursue its campaign to seize the Donbas area of eastern Ukraine.

Ukraine’s pipeline operator said Tuesday it was stopping the flow of gas through Sokhranivka because it had lost control of Novopskov, a gas-compressor station close to the Russian border. Russian forces had interfered in the pipeline network, including by siphoning off gas, in a way that endangered the stability of the broader system, the Gas Transmission Operator of Ukraine said.

Kremlin spokesman Dmitry Peskov, in a press briefing Wednesday, said Russia “has always reliably fulfilled and intends to fulfill contractual obligations.” A spokeswoman for Gazprom didn’t respond to a request for comment. In a statement Tuesday, a spokesman for Gazprom said Ukrainian gas specialists had continued to work at Sokhranivka and Novopskov and that it was impossible to pipe the gas through another entry point.

But gas flows appeared to switch around Wednesday, analysts and traders said. Shortly after the cutoff, gas moved in greater quantities through a separate entry point in Ukraine-controlled territory near the city of Sumy.

Ukraine has several hubs for receiving Russian gas, but only two entry points are included in the country’s current contract with Gazprom, a deal agreed to in 2019, according to the heads of Ukraine’s state gas company, Naftogaz, and its pipeline-network operator.

The two executives, in a press conference Wednesday, told reporters that Ukraine has asked Gazprom to increase flows through the alternative line to compensate for the stoppage in Luhansk. They said Russia in past years has piped much more gas through the alternate route than it currently is sending through.

Despite the war, Gazprom has kept up its contractual payments, called transit fees, to Ukraine for the right to send gas across the country, said

Yuriy Vitrenko,

chief executive of Naftogaz. In 2020, annual gas-transit capacity provided by Ukraine to Gazprom was worth $2.1 billion, according to Naftogaz. Analysts estimated the 2019 five-year contract between Gazprom and Naftogaz, covering 2020 to 2024, was worth about $7.2 billion.

Ukraine’s contract with Russia doesn’t prohibit rerouting of supplies into Ukraine, the executives said. If Gazprom purposely limits supply into Ukraine, they’ll be delivering less gas to customers in Europe, Mr. Vitrenko said: “It would be probably the first case of so-called self-sanctioning by Gazprom and by Russian entities.”

If the Ukraine route were cut off entirely, it would pose a huge challenge to a European economy that has grown accustomed to running on cheap Russian energy.

Moscow has sought over the past two decades to bypass Ukraine, building, with the help of Berlin, the Nord Stream pipeline under the Baltic Sea to Germany. That subsea pipe is now the main route for Russian gas into the EU. Another option is Yamal, a pipeline that threads through Belarus and Poland. Nonetheless, almost a third of Russian gas-pipeline exports to the EU still ran through Ukraine in the final quarter of 2021. The EU buys about 40% of the gas it burns to heat homes, fire factories and generate electricity from Russia.

The stoppage in Luhansk adds to nervousness among energy traders who were rattled in late April when Moscow halted gas exports to Poland and Bulgaria. Gazprom said it hadn’t received payment in rubles from the two countries as required by a decree by President

Vladimir Putin.

As Europe races to wean itself off Russian energy, American natural-gas producers are struggling to meet the demand and prices are rising. Factors including extreme weather and equipment needs have created a bottleneck amid the war in Ukraine. Illustration: Laura Kammermann and Sharon Shi

The EU is in the process of banning Russian coal and is working on a deal that would also phase out imports of oil. Natural gas, however, hasn’t been targeted as it is the hardest fuel for Europe to source from elsewhere.

The EU and the U.S. have pledged to expand liquefied-natural-gas exports to Europe through 2030. But the U.S. is already sending all it can to Europe, and industry officials say expanding volumes will require new, multibillion-dollar export terminals. In Europe itself, LNG import capacity that was unused last year could replace just under 29% of Russian pipeline gas supply, according to Natasha Fielding, an analyst at Argus Media.

Write to Joe Wallace at Joe.Wallace@wsj.com and Jenny Strasburg at jenny.strasburg@wsj.com

Copyright ©2022 Dow Jones & Company, Inc. All Rights Reserved. 87990cbe856818d5eddac44c7b1cdeb8

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Science

In a sea of magic angles, ‘twistons’ keep electrons flowing through three layers of graphene

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In the three layers of graphene depicted here, local twist angle can range from around 1.5 degrees (blue)—close to the “magic angle” for this device—to around 1.9 degrees (red). The arrow shows a twist angle vortex, or twiston. These areas of disorder help make the overall device more orderly. Credit: Simon Turkel

The discovery of superconductivity in two ever-so-slightly twisted layers of graphene made waves a few years ago in the quantum materials community. With just two atom-thin sheets of carbon, researchers had discovered a simple device to study the resistance-free flow of electricity, among other phenomena related to the movement of electrons through a material.

But, the angle of twist between the two layers has to be just right—at the so-called “magic” angle of 1.1 degrees—for the phenomena to be observed. That’s because atoms in the layers want to resist the twist and ‘relax’ back to a zero angle, explains Joshua Swann, a Ph.D. student in the Dean Lab at Columbia. As magic angles vanish, so does superconductivity.

Adding a third layer of graphene improves the odds of finding superconductivity, but the reason was unclear. Writing in Science, researchers at Columbia reveal new details about the physical structure of trilayer graphene that help explain why three layers are better than two for studying superconductivity.

Using a microscope capable of imaging down to the level of individual atoms, the team saw that groups of atoms in some areas were scrunching up into what Simon Turkel, a Ph.D. student in the Pasupathy Lab, dubbed “twistons.” These twistons appeared in an orderly fashion, allowing the device as a whole to better maintain the magic angles necessary for superconductivity to occur.

It’s an encouraging result said Swann, who built the device for the study. “I’ve made 20 or 30 bilayer graphene devices and seen maybe two or three that superconducted,” he said. “With three layers, you can explore properties that are hard to study in bilayer systems.”

Those properties overlap with a class of complex materials called the cuprates, which superconduct at a relatively high temperature of -220 °F. A better understanding of the origins of superconductivity could help researchers develop wires that won’t lose energy as they conduct electricity or devices that won’t need to be kept at costly-to-maintain low temperatures.

In the future, researchers hope to link what they see in their scans with measurements of quantum phenom in trilayer devices. “If we can control these twistons, which all depend on the angle mismatch between the top and bottom layers of the device, we can do systematic studies of their effects on superconductivity,” said Turkel. “It’s an exciting open question.”

Study improves the understanding of superconductivity in magic-angle twisted trilayer graphene

More information:
Simon Turkel, Joshua Swann, et al. Orderly disorder in magic-angle twisted trilayer graphene. Science 376, 193-199 (2022) DOI: 10.1126/science.abk1895
Provided by
Columbia University Quantum Initiative

Citation:
In a sea of magic angles, ‘twistons’ keep electrons flowing through three layers of graphene (2022, April 8)
retrieved 10 April 2022
from https://phys.org/news/2022-04-sea-magic-angles-twistons-electrons.html

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US

Yosemite Falls is flowing again thanks to that major storm that walloped the drought-choked US West

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Water surged over the 2,425-foot falls Monday, just four days after the same majestic rock face appeared as only a dry canvas for the sun’s glow, Yosemite National Park’s webcam feeds showed.
About 7 inches of rain came down across Yosemite National Park from late Sunday evening through late afternoon Monday — with lower totals in the southern and western sections — said Jerald Meadows, meteorologist-in-charge at the National Weather Service office in Hanford, California.

“That’s definitely getting into that historical rainfall realm,” he told CNN on Tuesday. “It’s definitely significant.”

The conditions made for the season’s first heavy, wet snow across the Sierras and soaking rains for the coastline and valleys across central and Northern California. The system has since pushed east, ushering severe storms Tuesday into the Plains.
“We had quite a storm, with over six inches of rain in Yosemite Valley over the past 36 hours,” park managers posted Monday to Facebook.

“We don’t have any direct measurements, but sensors suggest a few feet of snow fell at the higher elevations. Snow level for much of the storm was high, causing rivers and creeks to rise substantially (8.5 feet on the Merced River at Pohono Bridge, 1.5 feet below flood stage).”

The storm system indeed broke records in coastal areas, with San Francisco seeing by “far the wettest Oct day ever.” Sacramento set a new 24-hour rainfall record, the weather service office there said.
“It’s been a while since we’ve seen water moving across the falls,” Meadows said of Yosemite’s natural wonder, nodding to California’s long and ongoing drought.

“What typically brings us good waterfalls over Yosemite Falls is our snow pack, and last year, snow pack was very minimal,” meaning the flow that usually lasts until June or July “dwindled in March and April,” he told CNN.

The falls are flowing really well now, in part, because of how little rain was absorbed into the parched soil, said Meadows.

“So, it may be a faster dry-up than normal … a more brief period of flows than we normally see,” he said.

As for how long Yosemite Falls might maintain its iconic grandeur, “all indications right now are we are looking at a drier-than-normal precipitation year,” Meadows said. “The falls could yet again become dry into the November-December time frame.”



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Health

Is this what’s causing long Covid? Virus stops oxygen flowing around the body properly, study finds

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Changes to blood cells caused by the coronavirus may explain why so many patients suffer from long Covid, researchers say.

German researchers have found that the virus alters the size and stiffness of red and white blood cells, making it harder to get oxygen and nutrients around the body. 

Their small study of 55 people found that these changes can last for several months, which may explain why many Covid patients become ‘long haulers’. 

They believe the disruption to oxygen flow is the root of the common symptoms which plague long Covid patients – breathing issues, tiredness and headaches. 

But these physical alterations to the blood cells may also explain why some very sick Covid patients develop blood clots or suffer organ damage.

Scientists from the Max Planck Center for Physics and Medicine in Germany, who made the finding, analysed blood samples of current and former Covid patients and compared them to healthy volunteers.  

Long Covid is an umbrella term encompassing symptoms that persist for more than a month and is poorly understood. 

But official figures suggest hundreds of thousands of people across the UK have been suffering from the condition.

Fatigue was the most common symptom, affecting an estimated 535,000 people, followed by shortness of breath striking 397,000 and muscle ache hitting 309,000, according to the Office for National Statistics

The researchers found that blood cells were different sizes and shapes in people who were healthy (left), previously had the virus (middle) and had currently had the virus and were hospitalised (right). The graphs show how deformation increased slightly for people who had the virus, while those currently infected had cells that were much more deformed 

The graph on the left estimates what blood cells look like in health (grey), recovered (green) and currently infected (yellow) patients 

The researchers found volunteers who had Covid suffered poorer blood circulation, limited oxygen transport and blood clots. 

‘These are all phenomena in which the blood cells and their physical properties play a key role,’ they said in their report, which was published last month in Biophysical Journal. 

WHAT ARE THE LONG-TERM SYMPTOMS OF COVID-19? 

Most coronavirus patients will recover within a fortnight, suffering a fever, cough and losing their sense of smell or taste for several days.

However, evidence is beginning to show that the tell-tale symptoms of the virus can persist for weeks on end in ‘long haulers’ — the term for patients plagued by lasting complications.

Data from the Covid Symptom Study app, by King’s College London and health company Zoe, suggests one in ten people may still have symptoms after three weeks, and some may suffer for months.

Long term symptoms include:

  • Chronic tiredness
  • Breathlessness 
  • Raised heart rate
  • Delusions
  • Strokes
  • Insomnia
  • Loss of taste/smell
  • Kidney disease 
  • Mobility issues
  • Headaches
  • Muscle pains
  • Fevers 

For those with more severe disease, Italian researchers who tracked 143 people who had been hospitalised with the disease found almost 90 per cent still had symptoms including fatigue two months after first falling unwell.

The most common complaints were fatigue, a shortness of breath and joint pain – all of which were reported during their battle with the illness.  

Source: NHS

The scientists examined over four million blood cells from 17 patients acutely ill with Covid aged between 41 and 87, from 14 people aged 27 to 76 who recovered and from 24 healthy people aged 26 to 81 as a comparison group. 

They measured the shape of red and white blood cells using a microscopic camera and analysed the data on a computer. 

Red blood cells – vital for carrying oxygen and nutrients around the body – were found to be drastically different sizes and shapes in Covid patients. 

The researchers believe this can make blood clumpy and therefore harder to get oxygen around the body.    

Additionally, they found that the size and shape of white blood cells – a key part of the immune system – in patients with the virus were also found to be deformed in Covid patients.     

It comes after official figures suggested hundreds of thousands of people across the UK have been suffering from long Covid. 

Nearly one million people were found in May to be experiencing long Covid – defined as symptoms which last for more than four weeks after infection, according to the Office for National Statistics.

An estimated 385,000 were struggling with persistent symptoms that had gone on since last summer.

Around two-thirds of those with long Covid said it restricted their ability to carry out day-to-day activities. Symptoms include organ failure, tiredness, shortness of breath, hair loss and brain fog.

Fatigue was the most common symptom, affecting an estimated 535,000 people, followed by shortness of breath striking 397,000 and muscle ache hitting 309,000.

Lib Dem MP Layla Moran, chairman of the All-Party Parliamentary Group on coronavirus, said: ‘We’ve heard how the patchwork of support services for long Covid patients is already overstretched.’

Previous research has estimated that as many as two million people in England could be suffering ongoing symptoms after a Covid-19 infection.

It comes after a study found that only a small proportion of cases of long Covid are being recorded by GPs.

Experts from Oxford University and the London School of Hygiene and Tropical Medicine said their study raised questions about how long Covid is diagnosed, recorded and managed in the NHS.

They found that only 23,273 cases were formally recorded between February 2020 and April 2021 at GP practices in England.

More than a quarter of practices had never logged a case, according to the article in the British Journal of General Practice.

Ms Moran said: ‘Covid is not like the flu, it can cause long-term serious illness in otherwise young and healthy people, including children.

‘Even those who are not hospitalised have a risk of developing this debilitating condition, leaving them needing ongoing support for many months to recover.’

She added: ‘The new Health Secretary must consider the impact of long Covid ahead of lifting restrictions on July 19 to prevent another wave of cases that could have a devastating impact on our health service and economy.

‘Gavin Williamson must also consider the risk posed by long Covid to pupils as part of plans to relax Covid measures in schools.

‘The Government’s current approach risks condemning thousands more people to live with the cruel impact of long Covid while struggling to access the support they need.’

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