Science News Jan 11 (Patreon)

[This is a transcript with references]

Welcome back everyone, I hope you had a good holiday break. We have quite a lot to talk about today, so buckle up. First, we have an anomaly in particle physics that disappeared and an anomaly in cosmology that was confirmed. Then we have some amazing footage from the surface of the sun, disks that defeat the second law of thermodynamics, we learn how you can see something without looking at it, talk about a new method of cooling, the demise of science, the technology of 6G, what offshore windfarms do to marine life, and of course, the telephone will ring.

The B-meson anomaly has disappeared in recent data from the Large Hadron Collider, LHC for short. It was the particle physics anomaly which attracted the most attention in the past years, based on a slight violation of a symmetry known as “lepton universality”. In a recent analysis of data from the LHCb experiment, the anomaly is gone, and the results are compatible with the standard model.

This anomaly had been widely reported as a possible sign of physics beyond the standard model, often by portraying it as a hint for a "new force of nature”. That LHCb didn’t find the anomaly doesn’t mean it’s gone for good because LHCb is only one of several experiments that claimed to see it. So the patient isn’t dead but on life support and the machines are beeping loudly.

There are two other anomalies in particle physics which have recently attracted attention. One is the muon g-2 measurement that slightly deviates from the theoretical prediction. It was first found in Brookhaven 20 years ago and then confirmed at Fermilab two years ago. This one has never been a particularly convincing anomaly because physicists have long suspected that the reason for the discrepancy between prediction and observation isn’t the theory, but rather that it’s extremely hard to calculate the predicted value from the theory.

The third anomaly that you may have seen in the headlines last year is a measurement of the mass of the W-boson. I talked about this in more detail in an earlier video. In this case the anomaly doesn’t come from a new measurement, but from a new analysis of old data. The new analysis has supposedly a very small uncertainty which brings it in tension with other sets of data. I suspect that later this year other groups will have a few things to criticise on that data analysis.

Two years ago I told you about a quasar measurement that came out completely wrong -- a stunning 4 point 9 sigma away from the prediction. What they did in this work was to calculate the motion of our galaxy relative to all the other matter in the universe, and relative to the radiation from the cosmic microwave background. According to the currently accepted standard model of cosmology, the two results should agree. They do not.

This analysis has now independently been repeated by a second group, which just reported their results on the pre-print server. This paper has not yet been peer-reviewed, but they confirm the anomaly and indeed they find an even higher statistical significance of 5 point 7 sigma.

I really think cosmologists should pay somewhat more attention to this anomaly, what do you think, Albert?

David Dayag is an astrophotographer in Israel who has amassed quite some equipment to point at the sky. And with that he takes the most amazing videos of the surface of the sun.

David has built his own cooling device so that the sunlight doesn’t melt his equipment and that has certainly paid off. His videos beautifully show filaments of plasma on the surface of the sun with the occasional outburst. Those arcs you see here are larger than our entire planet. David has his own video channel where you can see his footage in more detail, so go and check this out, link’s in the top right corner and the info below the video.

By the way you can submit topics for our news show by replying to our newsletter that you can sign up to at sabinehossenfelder dot com slash newsletter. The newsletter is completely free and it contains some extra material that doesn’t make it into the weekly video.

Physicists are pretty fond of the second law of thermodynamics. It’s the law! So, when something comes along that appears to violate it, we take notice.

Researchers from the University of Tokyo just published a paper about simulations of spinning disks in a fluid that spontaneously unmix. Depending on how the disks rotate and how fast, they separate in different ways. The researchers say that this resembles effects which have been observed in bacteria, cells, and zooplanktons, but also insects, birds, and fish. This unmixing doesn’t come from a direct interaction between the disks. It's induced through turbulence which the spinning disks induce in the flow of the fluid which then affects the motion of nearby disks, effectively either repelling or attracting them.

Of course this doesn’t really violate the second law of thermodynamics. It’s the law after all. It’s just that there’s energy in the spinning of these disks and energy can be used to counteract the growth of entropy. Eventually the energy in the spinning would entirely disperse into the fluid and the disks would get mixed up after all.

The researchers hope that this work may lead to greater understanding of how microorganisms move, and how living systems spontaneously organise themselves.

Scientists from Aalto University in Finland have demonstrated that they can measure the presence of an electromagnetic wave without looking at it. This is called an “interaction-free” measurement and it’s the maybe weirded part of quantum physics.

Think of a particle that goes two directions at the same time. You put a measurement device in one of the paths, say the one going right. If the detector clicks, then you know the particle went right. Then the wave-function collapses from one describing both directions at the same time to one going only right. But here’s the thing. If the detector doesn’t click, then you know the particle went left, and the wave-function collapses – even though you never interacted with the particle.

The researchers from Finland have now used such an interaction-free way to find out whether an electromagnetic wave is present without touching it. As detector they used a transmon three-level system. “Transmon” is short for “transition monostable” which is a tiny superconducting circuit that, if you leave it alone, settles in one particular energy state. It’s similar to a superconducting qubit, but it can take on three different energy states rather than just two.

They prepared the transmon so that it’d reveal the presence of an electromagnetic wave when it didn’t interact with it. And that indeed worked. The results of the measurements agree amazingly well with the prediction.

What might it be good for? Well, one of the biggest problems with quantum computing, besides trying to explain it, is getting information out of the processor. It’s a problem because quantum states can change when you measure them. An interaction-free measurement scheme like this could make the readout less disruptive.

Hello?

Hi Rishi, Happy New Year!

Maths to 80? Oh 18.

Well by the time they’re old enough to vote you’re long gone anyway.

Sure! Talk soon!

Researchers at the Lawrence Berkeley National Laboratory in California have found a new cooling method that could be used in refrigerators, and that is more environmentally friendly than the currently most widely used one.

Refrigerators currently use gases for cooling because their temperature changes when they contract and expand. If you compress gas it heats up, if it expands it cools down. If you pump the gas from one place to another while expanding and contracting it, you can use it to transport heat out of a container, like your fridge.

Some gases are better at transporting heat than others. A type of gas that’s particularly good at it are chlorofluorocarbons, CFCs for short. Unfortunately, they turned out to destroy the ozone layer and most nations agreed to discontinue them with the 1987 Montreal Protocol.

CFCs have been widely replaced with hydrofluorocarbons, HFCs for short. Problem with those is that they’re greenhouse gases. Indeed, they are thousands of times better at trapping heat in our atmosphere than carbon dioxide. These gases are normally sealed inside a well working refrigeration system, but they can be released during the production process or when the refrigerator becomes old and leaky.

The Montreal Protocol was therefore extended in 2016 to include a 45 percent reduction in use of hydrofluorocarbons by 2024.

This so-called Kigali Amendment was signed by the US the EU and more than 140 other states. But as we all know that someone has signed some protocol doesn’t mean anything.

Luckily scientists have found that the HFC gases can be replaced by solid or liquids which can’t escape into the atmosphere. These materials would trap and release heat much like gases, but not when they’re compressed and expanded, but when they change phase, for example from a solid to a liquid and back. This idea in and by itself isn’t new, but the methods that have been tried so far have created fairly small temperature differences and were not very efficient.

The authors of the new paper use the concentration of ions in a solution of salts to change the melting point of a material; it’s called ionocaloric cooling. This allowed them to create a temperature difference of a stunning 25 degrees Celsius with only 0 point 2 Volts. Their method is both more efficient than previous ones and creates a larger temperature difference.  Moreover, they describe the substance as environmentally benign, non-hazardous, nontoxic, and non-flammable. It doesn’t release greenhouse gases and actually binds carbon dioxide in the production.

Nostalgia isn’t what it once was, but science isn’t either. Researchers from the universities of Minnesota and Arizona have found that progress is levelling off in the physical science, chemistry, computer science, and even biomedicine.

They analysed 45 million papers stretching back to 1945, as well as 3 point 9 million patents. They extracted both the language used in the paper, and how the papers were cited, especially whether subsequently published research cited the paper itself, or the paper’s references. They combined this data into a metric called the CD Index. It’s got nothing to do with music, but it measures whether a paper “consolidates or destabilizes” the citation pattern. The idea is that the biggest breakthroughs in science make previous work redundant.

Using this metric, they found clear evidence that both papers and patents have become less disruptive over time in all areas that they looked at, and it persists in the top journals such as Nature and Science. The trend is accompanied by a change of language. They found that words such as ‘produce’ and ‘determine’ were more likely to be used by scientists in the 1950s, while today terms such as ‘improve’ and ‘enhance’ are used more frequently.

The team says that this doesn’t mean that the quality of the scientific research declines, but that it instead shows a fundamental shift in the nature of scientific inquiry. Scientists are making fewer and fewer breakthrough discoveries and instead work out the details of the knowledge that we already have.

Though from personal experience I’d like to caution that one of the reason scientists are citing older papers more now than 40 years ago is that it’s much easier to find those references and it’s become kind of fashionable to cite some super old papers.

For example, these are the citations of Einstein’s 1905 paper about the electrodynamics of moving bodies that led to the development of special relativity. It’s probably not a coincidence that the number of citations is strongly correlated with the number of internet users. Albert is somewhat depressed, but he agrees.

The idea that scientific research is becoming less novel and less disruptive, is itself neither new nor disruptive. It complements earlier findings that showed papers, patents and even grant applications have become less novel, and less likely to connect disparate areas of knowledge, both of which are known precursors of innovation. Good thing we have YouTube for our daily dose of provocation.

Wireless networks are constantly being updated. At the moment, most of you probably use the 4th generation of wireless networks, 4G for short, with the switch to 5G on the way in many countries. I talked about the problems with 5G in this earlier video but mobile companies are already working on 6G. Research from Northeastern University has now demonstrated how this new technology could look like.

6G will use frequencies even higher than 5G. 5G tops out at 71 GigaHertz and 6G will use frequencies above 100 Gigahertz. The problem with those high frequencies is that they are easily blocked by obstacles, such as trees, houses, or people. Moreover, they trigger resonances in air molecules, which leads to absorption or distortion. This is why they haven’t been used for telecommunications so far: They don’t lend themselves to long-distance transfer of information. You can get around this by increasing the transmission power, but that becomes unhealthy very quickly.

Another problem with the high frequencies is that the common technology for imprinting information on the carrying frequency by using a mixer doesn’t work. The existing mixers just can’t handle it. The Northeastern team worked around that by encoding the information directly into the signal. That way, the team was able to transfer data over two kilometres at around 200 GigaHertz which is a new record. They managed to reach multi-gigabit speeds that left current 5G in the dust.

Since someone has to say it: two kilometres isn’t exactly a lot. But, well, 6G isn’t supposed to be rolled out until 2030 anyway, so they have some years left to figure out how to get it done.

So far the biggest problem with wind turbines was that they occasionally shred a few birds to pieces. But it turns out that fish may be a bigger problem than birds. A new study from the Helmholtz-Zentrum Hereon, suggests that large offshore windfarms have a negative impact on marine ecosystems.

The team used a computer model to simulate the consequences of increasing the amount of wind farms in the North Sea under current plans in the next 15 years. We already knew that wind turbines make the wind more turbulent and slow it slightly. This affects the horizontal flow of water, changing its temperature distribution.

The new model now shows that these changes in the water flow also affect the distribution of nutrients including plankton. According to their results, in the presence of large windfarms, the amount of biomass in the sediment rises, and the oxygen level falls, particularly in deeper areas. This in return changes the distribution of food and habitat for many fish species, especially young ones. Just what the consequences would be of all that, the model can’t tell. But I guess we’re going to find out because last time I looked fish didn’t vote.