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Science News Oct 3
🕑 Added 2023-10-03 17:26:26 +0000 UTC[This is a transcript with links to references.]
Welcome everyone to this week’s science news! Today we’ll talk about the Nobel Prize in physics, yet another superconductor retraction, whether Integrated Information theory is pseudoscience, why antimatter doesn’t anti-gravitate, sand that flows uphill which I swear has nothing to do with antigravity, the world’s most powerful X-ray laser, how life could come about on other planets, why we might go extinct sooner than expected, and of course, the telephone will ring.
The Nobel Prize in physics was awarded today for attosecond physics. An attosecond is a billionth of a billionth of a second, or ten to the minus 18 seconds. Just for context, that’s really short.
I think the Nobel prize committee made a really good choice here, giving the prize to Pierre Agostini, Ferenc Krausz, and Anne L’Huillier. If you just listen to me, you might get away thinking we’re pushing the frontiers of physics either by looking at very long distances or very short distances, but attosecond physics is pushing a completely different frontier, that of short times.
The most common method for generating attosecond pulses is through a process called High-Harmonic Generation. For this you shoot laser pulses into a cavity that contains gas normally that’s some kind of Noble gas and that creates higher harmonics of electromagnetic waves. You have to get them to overlap so that they amplify in some places and cancel out in others and that gives rise to those very short pulses. You direct them at a sample and measure what comes out.
Attosecond physics is a research area that’s just a little more than 20 years old or so. It’s interesting because attoseconds are the typical time span at which electrons moves around. These experiments therefore tell you for example how long it takes for an electron to get ejected from a molecule, what the electrons actually does. And this tells you a lot about the structure of the molecule and its chemical properties. You can use this to for example to study biological samples or to better understand how materials behave.
But it’s not just about observation, it’s also about manipulation. You can use these attosecond pulses to make tiny currents flow in very short busts and that is super useful in the area of ultrafast electronics. This research quite possibly one day will give rise to faster computers.
I love it when the Nobel Prize in physics is awarded because everyone is like wooo physics, which is how I feel the whole year. It might even get people interested in physics, for about an attosecond.
A physicist who claimed to have created a room-temperature superconductor earlier this year is about to have another paper retracted for academic misconduct.
A superconductor is a material without electric resistance. All known superconductors either require very low temperatures or high pressure to work. If we had a material that was superconducting in an everyday environment that’d be a really big deal because it could dramatically improve the efficiency of the entire electric grid.
Today’s news is *not about the LK99 superconductor from the Korean group that made headlines in August, but it’s a different story that we reported on in March. It’s the story of Ranga Dias at the University of Rochester in the United States. He claimed that he’d produced a sample of lutetium hydride that was superconducting at room temperature, though he had to put it under pressure.
Dias has somewhat of a reputation. Three years ago, a team also led by Dias already published a paper in Nature about a supposed superconductor breakthrough. The paper was retracted last year after other scientists raised doubts about the data analysis. The story from March drew attention to another paper that had been published earlier in PRL and which has now also been retracted due to data anomalies. There are also allegations that Dias plagiarized parts of his PhD thesis.
He now stands to lose a third publication. In early September, Nature put an editor’s note on his paper from March, saying that the reliability of the data is in question. According to the Wall Street Journal, several of Dias’ colleagues have asked Nature to retract the paper because, they say, Dias misrepresented the data. The magazine Science further reports that Dias had a lawyer send cease-and-desist letters to six colleagues who had raised accusations, warning them about potential legal consequences.
The biggest issue with the paper is the graph that supposedly shows the drop of the resistivity to zero, which is the hallmark of superconductivity. This graph relied on a noise subtraction that might have subtracted a bit too much. As several people already pointed out in March, without this noise subtraction, the neat drop of the resistivity disappears.
This is all a bit embarrassing for the editors at Nature. You’d think they’d have made more effort with the peer review after the previous retraction. But to me the most amusing part of the story is that the pressure that’s required to make the material superconducting has widely been reported as “moderate”. I find this an interesting description for a ten thousand times atmospheric pressure, but then again maybe US universities have a different notion of “moderate pressure”.
And we have a second science drama this week.
One hundred and twenty four scientists have signed an open letter contesting one of the currently most popular theories of consciousness, causing quite the academic rift. Their letter takes issue with integrated information theory, IIT for short, which the signatories believe has been given more attention than it deserves.
According to IIT, consciousness is a property which derives from the connectivity of a system and the amount of information it can process. The theory aims at providing a way to quantify the level of consciousness. Since almost all systems process a little bit of information of some sort, IIT assigns low levels of consciousness to pretty much everything including trees and vegetables. It’s almost, but not quite, a panpsychic theory.
IIT’s biggest competitor is the global workspace theory, which says that the mind works kind of like a theatre, with different actors on the stage, and unconscious processes working behind the scenes.
In their letter, the signatories condemn IIT for its “panpsychistic commitments” and argue that “the pseudoscience label should indeed apply”.
The letter a backlash to recent articles in Nature and Scienceabout IIT, that the signatories feel overstated the acceptance of the idea. But several consciousness researchers have taken issue with letter, including Anil Seth who called it “disappointing” and “clickbaity,” and David Chalmers who likened it to “dropping a nuclear bomb over a regional dispute” and called it “unsupported by good reasoning”.
I side with Seth and Chalmers. You can’t just declare something as pseudoscience because you don’t like its “panpsychistic commitment”.
But to me that story was settled a decade ago when the computer scientist Scott Aaronson showed that you can create a simple system with the task of solving a particular mathematical problem, that according to IIT would have an incredibly high level of consciousness. This means that whatever the integrated information in this theory measures, it’s not in any meaningful way correlated with what we mean by consciousness.
So while I don’t think ITT is pseudoscience, I think it’s just wrong.
Hello,
Hi Rishi,
Students made Oxford the murder capital of medieval England? Maybe, but back then it was called anatomy.
You’re welcome.
The ALPHA collaboration at CERN has reported that antimatter does not antigravitate, surprising absolutely no one, except for a few headline writers who tried hard to make this result sound interesting.
Ok, let me tell you why it’s indeed interesting.
According to the standard model of particle physics, for each type of particle there’s an antiparticle. The antiparticle has the same properties as the particle but has the opposite electric charge. When particles and antiparticles touch, they annihilate and leave behind a burst of light. That’s pretty cool, but also makes it difficult to study them.
Physicists are very confident that antiparticles have normal gravitational masses and don’t fall up. This is because the constituents of atomic nuclei are held together both by particles and antiparticles. If antiparticles had negative gravitational mass, then atoms would have a different inertial mass than gravitational mass. The equivalence principle would be violated. We have extremely precise measurements that rule this out.
Still, CERN has made a lot of effort to produce not just antiparticles, but anti-hydrogen. Normal hydrogen is a positively charged proton with an electron around it. Antihydrogen is a negatively charged antiproton with a positron around it. The ALPHA collaboration contained the antihydrogen in a tall cylindrical vacuum chamber where they held it with magnetic fields. When they reduced the strength of the magnetic fields, the antihydrogen dropped. They measured how fast it dropped, and voila, it fell just like normal hydrogen.
The reaction of physicists on twitter was mostly “duh”. If you’re one of them I’d like to remind you that Einstein’s theory of gravity is not a quantum theory, and hydrogen atoms are very much quantum. We actually don’t know how the equivalence principle works for quantum particles, and testing it for antihydrogen is a pretty good idea. What do you think, Albert?
The US Department of Energy and Stanford University have activated the world’s most powerful X-ray laser. I hope they did it by pushing a big red button.
The big laser is called the Linac Coherent Light Source, LCSL for short.
Its laser beam is created by electrons. The electrons are first accelerated in a straight line by SLAC’s linear accelerator in California. Then, strong magnets force the electrons to move on a zig zag. This makes them emit radiation and there you have your laser beam.
LCLS was the first laser in the world to produce both “hard,” or very-high-energy, and “soft,” or lower-energy, X-rays.
This has allowed researchers to use the laser for a lot of different experiments, that includes testing the quantum properties of materials and molecules, as well as understanding chemical reactions, especially at the quantum level. Understanding the buildup of molecules has a wide range of applications from medicine to agriculture.
After the upgrade, the laser is ten thousand times brighter and eight thousand times faster. It’s far more efficient than previously and will reach higher resolution, too. It’ll be able to generate a nearly continuous X-ray beam with nearly a million pulses per minute. It owes its performance to a superconducting accelerator made up of thirty-seven cryogenic modules which keep it colder than outer space.
Does everybody dream of shooting with a big X-ray laser or it just me?
Hello?
Mr President,
Yes, dark matter is a really old idea, more than 80 years already, ah, a fresh and new idea, could just run for president I’m sure.
Mr President?
Newton said that what goes up must come down. This sand strongly disagrees.
If you’ve ever hung out on the beach or played in a sandbox, you’ve probably noticed that sand tends to flow downhill when it’s poured. But scientists in the US have found a way to “trick” sand, and similar granular materials, into flowing uphill instead.
They did it by coating silica, that sandy stuff manufacturers put in packets to keep products dry, in iron oxide. The treated silica still flowed downward when it was poured, but then the scientists used a magnet to apply torque to the particles. This caused particles to join up with one another in temporary chains that quickly broke, resulting in an uphill motion. With enough particles of treated silica, they could even get the material to move up a mini set of stairs.
This might seem like a pretty useless idea, but controlling granular material is really important in many industries, and who knows maybe one day it’ll even help us get the crumbles out of the popcorn bag.
A team of chemists and bacteriologists say that life on other planets might come about entirely differently than it did on our own planet, which might much increase our chances of finding life out there.
In their paper, they report looking for a certain type of Autocatalytic Cycles that’s a series of reactions which produce copies of the molecules that were necessary to get the reaction going. Such a reactions catalyses itself, so auto-catalytic. It’s a very basic type of reproduction, and these researchers think it’s the basis for life.
The team came up with no less than two hundred and seventy chemical recipes that could sustain an auto-catalytic reaction. Chemists can now take these combinations and test them in the lab to see what happens, and astrobiologists can use this finding to guide their hunt for life on other planets
“Would you like to take part in my autocatalytic cycle?” sure makes for a killer hookup line.
By the way, this video comes with a quiz on quizwithit, that’ll help you remember what we talked about.
Here’s a little existential dread for you. A group of scientists are claiming mammals will go extinct. And for a change, it’s not us who are to blame, but plate tectonics.
Geologists predict that Earth’s continents will converge roughly two hundred and fifty million years from now to form one big supercontinent called Pangea Ultima, though others have said it’d better be called Pangea Proxima.
In the new paper the scientists claim that the creation of this supercontinent would cause a lot of volcanic eruptions that’d release massive amounts of carbon dioxide. This, they say, would warm the planet so much that mammals simply can’t survive. Scientists have previously assumed that our planet would remain hospitable for life for approximately five or six billions of years, after which our sun will begin to turn into a red giant and roast earth’s surface.
That’s quite a claim. 250 million years are a long time for species to adapt, even leaving aside that by that time we might simply be able to pump the carbon dioxide back out of the atmosphere. But the next time someone asks if I want to visit America I’ll tell them I’ll wait until America comes to visit me.
Comments
What is the line between continued research into "just wrong" ideas and pseudoscience?
That's right, you can't do it in general relativity.
Gravity of antiparticles? >>> Physicists are very confident that antiparticles have normal gravitational masses and don’t fall up. … The equivalence principle would be violated. We have extremely precise measurements that rule this out. <<< If we follow Einstein's original idea that gravity is caused by the variation (i.e. decrease) of the speed of light in a gravitational field, we get a clear answer about antigravity. For in this view, gravitational acceleration is the refraction of light-like particles in the field. - Now there is no reason to assume that the rules for the speed of light are different for normal particles and antiparticles. Because the assumption that antiparticles fall upwards would mean that the speed of light for antiparticles is increased in a gravitational field. This is contrary to everyone's (not only Einstein's) understanding of relativity. - And I see no need to refer to quantum mechanics here.
The constituents of anti-matter in the atomic nucleus are the anti-quarks in the virtuell pions there, in other words, the storng force, holding it together? Sabine´s autocataclytic cycle, nice idea.
In her case, is not just progress, but also an object demonstration that a steely determination to stick to it and keep showing up, no matter what, can in the end prevail. And rightly so, if the "it" is right.
(1) Attosecond imaging, about this year's Nobel Prize of Physics winners contributions: That is really interesting. I remember reading two years ago about the actual use of ultra-short laser pulses to follow chemical reactions. As Nobel prizes are given usually to older people that have been for quite a while working on something considered important, this probably has been under development for quite a while. Twenty years seems about right. (2) Global Workspace Theory is how I have thought, even before hearing about this theory, how my own mind works. I don't know about yours. IIT, that assigns a degree of consciousness to mossy rocks as well as to myself, I have thought, since I first heard about it, as being a huge stretch. (3) Bad papers published in high-impact journals: I have had repeated experience of confronting this as a disgraceful form of fraud, or just as plain bad science. I have reviewed and rejected many, many such bad papers, all of which were, in the end, rejected by the editor responsible. And I was not the only reviewer. I understand that in some countries governments encourage people in scientific careers, by making it a requirement for promotion, to publish as much as possible in reputable foreign journals, European and North American in particular. The latest sent to me to review, about detecting perturbations in the ionosphere caused by the large volcanic explosion last year of the submarine volcano near the main island of Tonga, looked really good. So then I looked at the paper by the same authors, in one of the IEEE transactions, describing the method used, and it was utter garbage. Which points out two serious problems, not just one. (4) Regan's "Star Wars" project included the use of x-ray lasers to be launched into space to confront an all-out ballistic missiles' attack from the USSR. Teller was the main proponent: it took a nuke to make a bunch of metal rods send a strong pulse of x-rays as it volatized in the explosion, and Teller loved nukes for anything and everything. It proved infeasible at the time. I really hope that is not the ultimate pursued use of the new version commented by Sabine, as among other things it can do, one is to destabilize the present unspoken detente among some nuclear-armed states, particularly those that also are space-faring ones. (5) Pangea Proxima: The original Pangea supercontinent was mostly dry desert and had its volcanoes, but life evolved and prospered there all the same. I have not come across the article on Pangea Proxima, but I'll have a look at it, when I do.
Rad Antonov
Nice work on the ALPHA story. This was hardly a trivial experiment. Although the result might be “obvious” to some, we still have to check. Reminder, antimatter first showed up as a negative energy solution to the Dirac equation. We know the energy is not negative but as stated, these are quantum objects in a classical theory. The SLAC story was cool, not just because it was the second mention of a particle accelerator in the weekly news, but also because particle physicists as a group went unscathed. To be clear, calling out individuals for their blunders is fair game. That said, I wish we hadn’t wasted as much as an attosecond on Ranga. We already knew he was faking it. Instead, Kariko and the Nobel in medicine deserved airtime. For years this woman received no recognition, UPenn forced her out of her job, she left the country and her family behind to pursue her research in Germany, it’s impossible to resist drawing parallels to Meitner, but for a change, the story has a happy ending and a just outcome. Progress!
