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The Speed of Dark, Trouble for MOND, Physicists’ AI Problem, and Magic Nuclei
This week’s science bits from SWTG
Marcus Gee-Lim
April 22, 2026
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Dark Spots Break Speed of Light Limit
Researchers from Technion in Israel have filmed the motion of tiny dark spots that move faster than light. These dark spots are places where the light wave’s intensity drops to zero due to interference. They had the light propagate on a material (boron nitride) where it couples to the vibrations of the material. Then they measured the speed with ultrafast electron microscopy to confirm that it broke the speed of light limit. Concretely, they measured that the dark spots moved at 1.04 times the speed of light in vacuum.
This is possible because the dark spots themselves are patterns, and not physical objects. They can move faster than light just like the image of a laser pointer, swept across a distant surface, can move faster than light: Because the image is not a physical object, it is just a pattern formed from physical objects which themselves obey the speed of light limit. So this is a very neat demonstration, but it does not violate any known physical principle and no, it does not allow us to send information faster than light.
Paper here, press release here.
This week’s episode of Science News is about magic nuclei. If it’s been a while since you’ve taken a chemistry class, you’re lucky – over time, the periodic table has been expanding as physicists produce brand-new atomic nuclei. But the thing about these nuclei is they’re extremely short-lived, sticking around for less than a nanosecond. Recently, though, physicists say they’ve figured out a calculation that should help researchers create new nuclei that are much more stable. Let’s take a look. Let’s take a look.
New Data Backs Dark Matter, Contradicts Modified Gravity
Figure: Gallardo et al, PRL 136, 151002 (2026)
A group of astrophysicists put forward a new data analysis of how quickly pairs of galaxy clusters are moving towards each other. From this, they can calculate how gravity falls off with distance. They find the pull is consistent with an inverse-square law. This is in line with standard gravity, and far from the 1/R-like behaviour that one would expect for Modified Newtonian Dynamics (MOND). That makes this an interesting new large-scale test of gravity.
That said, I think that the press release and some coverage oversell it when they say this leaves “little doubt” that dark matter exists. What the result really does is show that one broad class of modified-gravity explanations does not fit these pairwise cluster motions well; it does not by itself identify what dark matter is, and it does not rule out every possible alternative model. Paper here. Press release here.
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Physicists Begin to See the Problem With AIs
In the foundations of physics, almost all published research is now bullshit: Useless calculations that do not solve any problem, but that are easy enough to perform and — most importantly — publishable. You only have to look at public media coverage to see that there are new “explanations” for dark matter or dark energy every other day, none of which we hear of ever again. If you want to weep, you can scroll through the gr-qc listings, because at this point they are mostly mathematical exercises in modifications of Einstein’s General Relativity that don’t describe our universe.
Of course the people who work in the field will go to lengths to deny the problem and get very upset when I call out their bullshit, but denial won’t work for much longer. The issue is that the current AI systems are now almost good enough to mass manufacture more of these bullshit papers which — going by the miserable quality standard in the field — would merit publication. For the researchers in the field to justify their existence, they will have to significantly raise the quality standard.
You don’t hear a lot of physicists admitting this, but the other week we saw a comment in Nature Astrophysics by Hiranya Peiris who points out that “If a Large Language Model can replicate your scientific contribution, the problem is not the LLM,” and that “The astrophysics literature had a quality problem long before LLMs arrived [...] The disease was already present.” He is entirely correct. Comment here.
