Superconductor Breakthrough -- What's Up With That?

Superconductor Breakthrough -- What's Up With That?

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Welcome everyone to this week’s science news.  Today we’ll talk about a potential breakthrough   in room temperature superconductivity, new  clues about the origin of water on Earth,   the best ever model of our geological  past, a recent report on academic freedom,   an image of the moon taken with a meta-lens,  hybrid coral reefs, a new institution dedicated   to finding the origin of life in the universe, the  first cross-country storage for carbon dioxide,   and of course, the telephone will ring. A team of American physicists has   announced a superconductor breakthrough, again. The group led by Ranga Dias of the University   of Rochester in New York says it has created a  material that becomes superconducting at room   temperature but it needs to be put under pressure.  To be precise, they need 10 kilobar of pressure,   which they call near-ambient. Where  I live, 10 kilobar is about ten  

thousand times atmospheric pressure, but  maybe it’s different if you publish in Nature. High-temperature superconductivity is basically  the holy grail of condensed matter physics. A   room temperature superconductor could  transport electricity without loss,   which would dramatically improve the efficiency  of the power grid and electronic devices. It would  

make magnetic levitation an everyday day thing.  It would be a really really big deal which is   why the topic attracts so much attention. And  to be fair, while 10 kilobar is still a lot,   it’s much lower than the pressure that  was required in previous experiments.  Here’s what they did. They took a thin  sheet of the rare earth metal lutetium,  

just about 100 micrometres thick, squished it  between two tiny diamonds, bathed it in a gas   made of 99 percent hydrogen, doped with 1 percent  nitrogen, and left it alone in a pressurized   reaction chamber overnight at 65 degrees celsius.  It’s only mildly more complicated than lasagne.  Then they squeezed the resulting compound,  lutetium hydride, between the diamonds and   watched it change colour at around 3 kilo bar,  from blue to pink to deep red. This clearly shows   that something is going on. The question is, what. Their major claim is that along with this colour  

change, the electric resistance also  changes. In this figure you see how the   electric resistance depends on temperature,  and how the transition temperature depends on   the pressure. The higher the pressure,  the higher the transition temperature.  Other physicists are somewhat sceptical of this  result, and for good reasons. The lead author,   Dias, has a shaky reputation after it  came out that he repurposed parts of   someone else’s doctoral thesis for his  own dissertation. And three years ago,   a team also led by Dias already published a  paper in Nature about a supposed superconductor   breakthrough. However, Nature retracted that  paper without the authors’ consent after other  

scientists questioned the data analysis and  said they couldn’t reproduce the results. And several people have already raised questions  about the data analysis in the new paper. First,   there is the way they get rid of noise in  their data. The raw data for the resistance   is available online and without subtracting  the noise subtraction it looks like this   graph on the left. Gone is the neat and  sudden dip to zero resistance. However,  

this might look worse than it is because the  tell-tale sign of the phase transition is this   sharp drop and this tail could reasonably be  due to other parts involved in the measurement.  Other people have pointed out that their  spectral analysis seems to be wrongly   labelled. This peak here isn’t lutetium.  One would instead expect magnesium to show   up here. But there’s no mentioning of magnesium  in the preparation of the sample. Then again,  

if it works, this might not matter all that much. Yet others have raised the point that the  resistance seems to have hysteresis, which means   that the curves for cool-down and warm-up are  not the same. Superconducting phase transitions   normally don’t have hysteresis. But while that’s  unusual, it’s been seen before in some materials. At the moment no one’s sure what to make  out of this. But there are without doubt   other groups trying to reproduce the results  as we speak and we’ll hear more about this   in the near future, so stay tuned. An international team of astronomers  

has discovered new clues about  the origin of water on Earth.  It’s long been a mystery why Earth has  so much water, not just on the surface   and in the atmosphere, but also in the crust,  mantle and core. The issue is that when our   planet formed from the same plasma that gave  rise to the sun, it was too hot for water to   form in appreciable amounts. So where does  it come from? Did the water form later? Did   it arrive with comets or meteoroids? Or do  we not understand the way that planets form?  The new paper looked for answers in a young  solar system, the Orion constellation,   one thousand three hundred and five light  years away. They use this system basically   as a proxy for looking at the past of our  own solar system. Here it is marked in  

red in the constellation, below the belt. For their observations they use the ALMA   telescope, a large radio telescope based in  northern Chile, and the got lucky. Usually,   water in the disk of a young solar system freezes  out into ice at some distance from the sun, and   then it can’t be examined with radio waves. But in  this case, the star has recently gone through an   accretion burst incident. This means it swallowed  vast amounts of matter and then exploded, kind of   like what happens when you read too many twitter  comments. This burst incident heated the disk,  

turned much of the water into gas, and  allowed the astronomers to measure it.  They were looking for what’s known as the  “flavour” of the water. Yes, water comes in   different flavours. Besides Coke zero, it could  be that one of the hydrogen or oxygen atoms are   isotopes of the most common ones, so they have  different numbers of neutrons in the nucleus.   For this study, they specifically looked for  the fraction of water in which one hydrogen   has been replaced with deuterium, known as  “semi-heavy water”. They found the ratio of   semi-heavy water to normal water to be roughly  2 parts in a thousand. This is comparable to the  

ratio found in the interstellar medium, that’s the  stuff that floats around between solar systems.  The researchers suggest that this means the  protoplanetary systems directly inherit their   water from the interstellar medium, and where  it’s cold enough it freezes onto planets,   and more mobile asteroids and comments which  can then redistribute it. This doesn’t entirely   solve the mystery of where Earth got its  water, because the ratio of semi-heavy water   to water on earth is much lower than what  they observed in this other solar system. 

However, if the water in protoplanetary systems  comes directly from the interstellar medium,   this means that it’s probably  abundant in many solar systems,   so if we ever move to another planet, there’s  a good chance you can surf there, too.   A group of Australian and French geoscientists  has developed the most detailed model ever of   how the landscape of Earth evolved  over the past 100 million years.  The new computer simulation allows scientists  to trace the rise and fall of mountains,   the forming of the continents, the flow  of rivers and sediments, the transfer   of sediments to the ocean, the movement of  tectonic plates, the effects of climate and   precipitation and how all these interactions  shaped the conditions for life on Earth. Remarkably enough, the model is precise down to  a spatial resolution of about ten kilometres,   everywhere on the globe, including the deep  ocean. This little movie shows the last one  

hundred million years’ evolution of our planet. Bringing past landscapes back to life is not   just interesting to look at. It’s also important  for predicting how Earth will respond to climate   change, because we still don’t fully understand  how carbon is reabsorbed from the atmosphere.   Ocean chemistry, atmospheric composition,  surface conditions, tectonic plate activity,   and biodiversity all interact with the  carbon cycle through feedback loops. It’s   really complicated. I guess someone’s got  to figure it out, but I’m glad it isn’t me.  Academic freedom has deteriorated  significantly over the past decade   in 22 countries whose population makes up more  than 4 billion people, half the world’s total,   according to the latest release of the  Academic Freedom Index. The Academic Freedom  

Index surveys the state of academic freedom in  179 countries. It is coordinated by the V-Dem   institute in Gothenburg, Sweden and a group and  the University of Erlangen-Nürnberg, Germany. The best academic freedom score this year goes  to Czechia, though much of Europe is in the   top group. At the rock bottom is North Korea. In this map, the pinker the colour the worse  

the situation for academic freedom. For their  evaluation they looked at freedom to research,   teach, exchange and disseminate  information, cultural expression,   institutional autonomy and campus integrity.  You can see that across big parts of the globe,   the state of academic freedom is poor. What’s  particularly worrisome in this year’s report is   that academic freedom has declined in the  three most populous nations in the world,   China, India, and the United States,  as well as Mexico and the UK.

In India, academic freedom began to decline  in 2009 and then took a steep dive after Modi   became prime minister in 2014. Since  2016, the report classifies India as   an electoral autocracy, rather than a democracy. The United States used to have a very high level   of academic freedom, but things changed when  Donald Trump took office as president in 2016. 

More worrying, four of five indicators of  academic freedom have continued to fall in   the U.S. since his successor, Joe Biden,  came to power. According to the report,   that’s because individual states have taken  aim at academic authority, that includes   banning certain topics such as critical race  theory and targeting tenure. In some states,   lobby groups are trying to have funding withdrawn  from gender and environmental studies, and various   groups are maintaining public “watchlists” of  researchers they claim are radical leftists.   However, the authors of the report also note that  despite all that scholars in the United States   remain able to publicly voice their opinion. In the UK, things have been slowly going  

downhill for about ten years or so. As  for Mexico, the trigger for diminishing   academic freedom has been the country’s  harsh austerity measures under president   Lopez Obrador who came into office in 2018. In China, things were bad already but got worse   after Xi Jinping became secretary general of the  Chinese Communist Party. Though, as you can see   academic freedom hasn’t yet reached absolute  zero. That’s because you still have freedom   of expression. You can say you agree with the  communist party or that you support the communist  

party or that you admire the communist party.  Plenty of options. The choice is only yours.  An American team of electrical engineers,  mainly at Pennsylvania State University,   has taken the first image of the moon  using a telescope fitted with a meta-lens.  Conventional telescopes have large  lenses and apertures made of bulky,   heavy materials such as glass. This for example is  the lens for the telescope that will be installed  

in the Vera Rubin Observatory in Chile. So materials scientists have been trying   to figure out how to make lighter, less  expensive, lenses by designing materials   with nanostructures, the meta-lenses. Meta-lenses are not lenses in the   traditional sense. They consist of several  layers, each about 100 nanometres thick,  

carefully configured so that they refract  light in just the right way to focus it. But   it’s been a challenge to make a meta-lens with an  aperture big enough to focus on celestial objects. In this new work, they made a meta-lens  by laser-etching patterns into silicon,   and then fused that to a silica substrate. You  can see the lens itself here in the middle of  

the bottom row. And the nanostructures that  act as tiny antennas are here in image f.   With this method they were able to create a  refractive metalens with an 8-cm aperture.  And that was big enough to  get an image of the moon,   even if it’s a blurry one. Here’s what they got. In case you’re kind of unimpressed because your   five year old took a better pic with his phone.  That’s quite possible, but the lenses in your  

phone are one of the reasons for its width,  and meta-lenses could be smaller, thinner,   and cheaper. And then you wouldn’t have to  worry so much that the five year old drops it. Hi Elon, Yes they used to say that money only  makes you happier up to a point. But   this new paper now found that more money  makes you happier. Unless it doesn’t.

Basically they say some people just don’t  get any happier. Why are you asking? Yes, I understand it must be difficult to be   rich. But buying twitter was a really  good start to solving that problem. Love you too. Bye. Researchers at the University   of Miami are building artificial coral reefs to  protect the city from storms and sea level rise. 

Earlier this month, they sank twenty-seven  concrete structures into shallow water 215   meters off the coast of North Miami  Beach. You can see from this overhead   drawing that they are nine meters apart,  in a line spanning thirty-five meters.  Miami is a hurricane hotspot. And hurricanes  can damage coastlines. So the researchers   came up with structures that can absorb the  energy of storm surges. The next step is to  

seed them with corals that have been hand-reared  at the university. According to their estimates,   adding corals to the structures will reduces both  wave heights and wave energy by 10 to 15 percent.  The project is important not just to  protect people living near the coast,   but also an attempt to restore sea life.  Since the 1950s, half of living corals  

across the ocean have died off from  ocean warming, ocean acidification,   overfishing, and disease. And the concrete  blocks are ugly enough to deter tourists.  An international group of scientists,  including two Nobel Laureates,   has established the “Origins Federation.”  It’s multi-disciplinary research consortium   aimed at understanding how life emerged in the  universe – and whether it exists anywhere else. The question’s been around ever since humans have  figured out there are other stars in the universe,   but now that we have found so many exoplanets  it’s become even more pressing. I find this   an interesting development because up  to now the attempt to find alien life   hasn’t been taken very seriously and this  is changing now. And while the field has  

traditionally been dominated by astronomers  and astrophysicists the new federation plans   to draw on disciplines as diverse as  synthetic biology and paleoecology. Why did they call it the origins federation?  I guess it’s either because there is already   an origins institute or because they’ve  watched too much Star Trek or possibly, both.  The federation was announced during a panel  discussion last week at the annual meeting of   the American Association for the Advancement  of Science in Washington, D.C. The founding   institutions are Harvard, Cambridge University,  ETH Zurich and the University of Chicago.  Notable people that’ll contribute to the  project are the Swiss astronomer Didier   Queloz who shared the Nobel Prize in physics  in 2019 for discovering the first exoplanet,   and Jack Szostak of Harvard, who shared the  Nobel Prize in medicine in 2009. His lab is  

currently trying to understand the transition  from chemical evolution to biological evolution.  The federation’s inaugural conference is scheduled  to take place at Harvard University in September.   All this would be easier if we could at  least agree on what we mean by “life”.  The Danish government has launched a deep-sea  graveyard for liquefied carbon dioxide. It’s   called Project Greensand, and it’s part of  the current spate of 200 or so carbon capture   and storage projects around the world that are  supposed to save us. CCS has become all the rage  

as nations try to meet net zero targets by 2050. At the moment, the world has about 3 dozen or so   carbon capture and storage facilities in  operation. The Danish project is so-far   unique because it’s the first to store carbon  dioxide from another country, in this case,   from a chemical production plant in Belgium. At the plant, the carbon dioxide is liquefied,   then shipped to the site of a depleted Danish  oil field underneath the North Sea. There,   it’s injected by a dedicated well into  a sandstone reservoir. The plan is that   it stays there forever, or at least until no one  can remember we put it there in the first place. 

The plan is that by 2030 this carbon cemetery will  store up to 8 million tonnes of carbon dioxide a   year. That’s about 13 per cent of current  Danish emissions and a sizeable share. But   it’s not all peaches and cream. It takes about  a fifth of those emissions just to capture,   transport, and store the liquefied gas. So, another little step of progress,   but I guess we’re still not done  dusting off the solar panels this week. I’ve been doing these YouTube videos for some  while now. And I still find it odd. Because,  

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2023-03-22 03:06

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