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Science News Aug 8
🕑 Added 2023-08-08 15:00:09 +0000 UTC[This is a transcript with links to references.]
Welcome everyone to this week’s science news. Today I have an update on the reproduction efforts for the supposed room temperature superconductor, LK 99, the first images from the Euclid mission, more trouble with Starlink satellites, first results from a new simulation for cosmological structure formation, how to steer drops with ultrasound, bacteria that make plastic, an improvement for wireless power transfer, better earthquake warnings, an attempt to predict war, and of course the telephone will ring.
Last week I told you about the new room temperature superconductor, LK99, that a Korean group claims to have discovered. Here is a super quick update.
Several groups all over the world have meanwhile produced the compound following the instructions of the Korean group. I will leave you a link to this handy summary in the info below. As you can see, the first results have been mixed but mostly negative or inconclusive.
They pretty much all confirm that the material is diamagnetic, that is, it will be repelled by magnets. And the stuff clearly has some weird magnetic properties. One Chinese group says the material is levitating as it should be if it was a superconductor and they have an arXiv paper to go with it.
There has also been a video by a Chinese group claiming they see flux pinning. Flux pinning is an effect in superconductors similar to the Meissner effect. In the Meissner effect, a superconductor floats because magnetic field lines cannot get in. With flux pinning they cannot get out, so the superconductor is held in place. Unfortunately there’s no paper to accompany the video, or at least I haven’t seen it.
Another Chinese group also says the material is superconducting but only at temperatures below 100 degrees Kelvin. They have a paper on the arxiv. There’s also been a theoretical investigation of the structure of the material which concluded that it’s possible that it’s a room temperature superconductor, but it might not necessarily be.
There have also been fake videos of floating rocks popping up on social media. This one is an example that the creator disclosed as fake to issue a warning, so be careful out there.
If you find all that a little bewildering, you are not alone. I think at the moment no one really knows what’s going on. What is clear is that the results about the behaviour of the material are inconsistent, and there has been no confirmation that the resistivity actually drops to zero at room temperature, but we’ll keep you up to date, so stay tuned. This is the most fun we’ve had in physics since cold fusion.
Even the James Webb Space Telescope had something to say about it by recently delivering this image of a question mark in deep space.
The European Space Agency released the first test images from the Euclid mission, and they’re absolutely dazzling. And yet they’re only a small glimpse at what’s still to come.
The Euclid mission launched on July first. A few days ago, it reached its final destination, that’s a small orbit around the Sun-Earth Lagrange point two, where it now sits alongside other instruments, like GAIA and the James Webb Space Telescope. The goal of the Euclid mission is to tell us more about the nature of dark energy and dark matter by creating a three-dimensional map of a part of the universe.
Euclid has two instruments, one detects light in the visible part of the spectrum, called VIS, and the other one detects light in the near-infrared. It’s called the Near-Infrared Spectrometer and Photometer, NISP.
For each of the new pictures, Euclid collected light for 100 seconds, but in the future, it’ll collect light for almost 500 seconds. This will give us even more detailed images of distant galaxies. Soon we’ll know more about what’s going on in other galaxies than on our own planet. Or maybe that’s already the case.
SpaceX has worked hard to make its satellites less disruptive in the visual part of the spectrum. But according to a recent paper by an international team of astronomers, Starlink satellites are unintentionally emitting radio waves.
The team used data gathered at the Low Frequency Array telescope in the Netherlands.
During their observation they saw 68 Starlink satellites crossing their image. 47 of those emitted radiation in the frequency range between 100 and 200 megahertz, that’s well below the frequency of the downlink communication signal, which is around 10-12 Gigahertz. They say that part of those signals don’t originate from the Starlink satellites but are reflections from a French radar system. Still, the rest seems to be unintended emissions from the satellites, and they spill into a frequency band that’s especially allocated to radio astronomy.
While there strictly speaking aren’t any laws preventing satellites from using that band, it’s what we might call a celestial faux pas. But the authors of the study say they’re in contact with SpaceX, and the company has indicated that it’s willing to try to resolve the issue to protect other astronomical projects.
As we have previously reported, Elon Musk’s company has indeed taken complaints by astronomers about reflections in the visible range seriously, and the second generation of Starlink satellites is far less shiny than the first.
Hello,
Hi Elon,
Nah, I think they’re disappointed you didn’t plaster the sky with flashing X-es.
No, please don’t. I was joking!
Elon?
An international team of astrophysicists has published the first results from a new computer simulation that shows how galactic structures form in the universe with unprecedented precision.
The computer simulation is called MilleniumTNG, where TNG stands for “The Next Generation”. They have not released a video, but a total of 10 papers that summarize various studies they have made.
MilleniumTNG is the largest high-resolution dark matter simulation to date. In this video you see its cousin, the IllustrisTNG simulation, which was impressive already and covered almost a billion light years in size. But the new simulation covers a region that’s nearly 10 billion light-years across.
This and similar computer simulations start in the early universe, with a distribution of only dark matter. They then calculate how the dark matter clumps. Normal matter is not included in those simulations because that’s too complicated. For the MilleniumTNG project, they run a separate simulation for galaxy formation with normal matter and then match that to the dark-matter only runs.
MillenniumTNG is the first such simulation that also incorporates neutrinos, tiny subatomic particles that lack an electric charge. Neutrinos don’t interact with electromagnetic radiation, and therefore act like dark matter in some respects. However, we know that they must have very small masses, and if dark matter was just made of neutrinos, then structures wouldn’t form quickly enough.
Neutrinos have so far been omitted from simulations because estimates say they add up to at most 1 to 2 percent of the dark matter mass. However, as observations are getting better, simulations have to get better too. And the MilleniumTNG simulations could then be used to pin down the masses of neutrinos.
The public data release is planned for next year, so we’ll have to sit tight for a bit longer to see the ultimate reality show of the universe, Season 1.
Scientists in Japan have developed a device to precisely steer tiny drops using ultrasound. This might seem like an arcane art, but it could have a lot of applications, from testing tiny medical samples to studying chemical reactions in unprecedented detail, to observing biological processes.
This new method works by placing the drops onto a mesh that’s hydrophobic, meaning it repels water. Then, ultrasonic waves are focused onto the mesh and pulsed in the desired direction. When the waves run parallel with the mesh, they move the droplets horizontally across the surface. When the waves run perpendicular to the mesh, they push the droplets upward, causing them to jump. With a bit of practiced control, droplets can even hop into a container.
In their paper, the scientists say that their method works for droplets up to 300 microliters and can make them jump up to 10 centimetres. That’s more than 20 times higher than the previously used methods.
I think this is really a story about scientists breaking up with pipettes. “Look, pipettes, it's not you, it's us. I think we need to see other tools.”
You’ve heard of bacteria that eat plastic, but have you heard that bacteria can also make plastic? Scientists in the United States have found a way to genetically engineer the bacterium e coli so that it turns plant sugars into molecules that can then be used to create recyclable bioplastics. It won’t be long now until food wrappers are more organic than the food itself.
The plastic these bacteria can produce is called polydiketoenamine, PDK for short. PDK is a flexible material that is used for products such as adhesives, shielding for cables, or watch bands. It’s usually made out of petroleum-based chemicals, but e coli can be coaxed into creating the chemicals used for producing it too. According to the researchers, more than 80 percent of the plastic can be produced this way without sacrificing structural integrity. Even better, they showed that the bioplastic can also be taken apart into its monomers and then be recycled almost indefinitely.
If this innovation reaches the market, it could both reduce the use of fossil fuels as well as plastic pollution. So, E. coli went all the way from causing urinary tract infections to saving the world, quite a plot twist.
Imagine your phone battery would automatically recharge while you’re inside a building. Wouldn’t that be great? Researchers from Aalto University in Finland have now found a way to make that a little more likely to happen.
The trouble with wireless power transfer is that at the moment you have only two options. You either use what’s called the near field of an antenna. For this, you place your device right next to the charger. This is how the existing wireless phone chargers work.
The other option is to go farther away and then use electromagnetic radiation that can travel a distance. But you can’t send power into all directions and hope you hit the phone, that would be incredibly inefficient. So you have to use a directed beam or radiation instead. This is how power is supposed to come down from those solar panels in space.
The issue with those beams is that, for one, they have to find the phone, and also, if you focus the power in a beam you have to ask how much of that will get dumped into humans should they get in the way.
In the new paper now they look at the intermedia distances, where you’re neither directly at the charger, nor are you very far away. So, a setting you might encounter in a room.
They have found a clever way to couple the antenna and the receiver so that even at intermediate distances the loss into radiation is suppressed.
It’s both an analytical study and an experiment. The researchers claim that technique allows efficient power transfer over a distance about five times larger than the antennas themselves.
The antennas in their experiment each had a radius of 3 point 6 centimetres, so that means they transferred power about 20 centimetres. That, admittedly, still isn’t much, but if it saves people half a step a day, I’m sure it’ll be a great success.
Seismologists in France say they might have found a way to predict whether an earthquake is coming on, at least sometimes.
They used what’s referred to as high-rate GPS time series data from more than 3000 stations worldwide. Then they compared the time-series with the timing of 90 high-magnitude earthquakes. In the data, they found a subtle precursor that might signal that a quake is on its way.
It’s what is called a fault slip, which sounds like gymnastics gone wrong, but it means the sudden displacement of geological features. That could be on either side of the fault line where the earthquake is about to happen. In some cases that happened as much as two hours before the earthquake, enough to evacuate people.
Unfortunately, the researchers point out that the method also picks up on a lot of false positives, where a fault slip happens but no major earthquake follows. So, as they say, more work is needed.
I talked extensively about all kinds of things that scientists have tried to predict earthquakes in two previous videos, and let me just say, none of those methods has been particularly successful.
Earthquakes have been so far like ninja attackers, taking us completely by surprise. But maybe one day they’ll be more like sumo wrestlers. Still dangerous, but at least you can tell when they’re coming.
Researchers in Austria have developed a theoretical framework to explain how conflict arises and spreads. They say that this might help us to better predict when wars arise.
The researchers collected data about the number of people participating in armed conflict, international tensions, economic circumstances, and fatalities. They assigned them to time-periods and locations and looked for causal connections between nearby locations. This allowed them to create a causal network, and to identify situations in which small conflicts snowball into bigger ones, resulting in what they refer to as a “conflict avalanche.”
They applied their model to some past cases in Africa and found it to work well. They also say that their analysis strongly suggests that current events in Sierra Leone are related to those in Liberia.
We’ve historically used a narrative approach to understand war. Statistical methods like this are instead built on the idea that individual decisions matter very little for collective dynamics, and that war is often a consequence of economic circumstances, environmental pressure, and failures of the systems that govern human interactions.
You see, in the end, we’re just big bags of atoms executing the laws of nature.
Comments
“This is the most fun we have had in physics since cold fusion..” 🤣🤣🤣
'Existential Physics': "We are so much more than just atoms". I'm afraid, you're ambivalent, Sabine 😊
