Science Notes (10/17/25)

This Science Notes series (a subset of the Friday Notes series) gives me a chance to record bits of science articles that catch my eye and seem worth sharing. I’ve been doing this since my library app provided access to a huge number of online magazines.

Nearly all of which don’t interest me — in some cases, seriously don’t interest me. Bridal and Fan magazines are an obvious example, but there are myriad magazines devoted to interests that don’t interest me at all.

But I do like the ones devoted to science, and some articles fit some receptor in my mind enough to generate a note.

Defying Gravity

The first one involves (and doesn’t solve) a puzzle I’ve had for a long time about gravity — the weakest of the forces. (Except I and many others don’t think gravity is a force in the same sense as the electromagnetic, weak, and strong forces. Specifically, there is no such “particle” as a graviton. Instead, gravity is the result of warped spacetime.)

This quote is from an article in New Scientist:

The trouble is, the weaker the force, the more rarely its particle interacts with other particles. And gravity is a very weak force – 10 trillion trillion times weaker than the force actually known as the weak force. We might think gravity is strong, seeing it pull an apple from its branch to Earth’s surface, but the gravitational attraction between a pair of apples is scarcely perceptible. That is why the prospect of spotting a graviton in an experiment has always been unimaginably slim.

But the undeniable thing is that the Earth does emit enough (supposed) gravitons to pull meteors, apples, and even paperclips towards it. The “force” of gravity we feel from the Earth is considerable. And obviously those putative gravitons are measurably interacting with meteors, apples, and paperclips.

So, it’s not quite clear to me why they should be so difficult to detect. Unlike (also putative) dark matter, the interaction with gravitons is clear and present.

I assume the problem is that individual gravitons interact … so weakly, I guess, that it’s a challenge to identify any specific interaction. We only see the effect of a huge number. But, again, I’m not clear on why that makes them so hard to detect.

Trillions of solar neutrinos stream through us every second, but they’re hard to detect because they tend to completely ignore us. Likewise, dark matter. But gravitons do interact with matter, so I’m puzzled.

An obvious answer, of course, is that there’s no such thing as a graviton, and gravity is just everything sliding down warped space (which is my take on it).

Ai and Negation

This bit caught my eye in part because a common typo for me is forgetting a negative (like “not” or “can’t”) in a sentence. Which reverses the sentence’s meaning. “The movie worked for me,” versus “The movie didn’t work for me”. For whatever reason, I often forget the negative. (And, no, I don’t think it’s at all Freudian.)

This bit caught my eye also because I’m interested in the capabilities and limits of large language models. It’s from New Scientist:

Both vision-language models and the large language models used in AI chatbots are based on the transformer model originally developed by Google researchers. Transformer models “are really good at capturing context-specific meaning” among strings of words, says Karin Verspoor at the Royal Melbourne Institute of Technology in Australia. But “not” and “no” work independently of context-specific meaning and “can appear in many places within any given sentence”, she says.

There seems to me a connection between the independence of words like “not” or “no” or “won’t” and the way I forget them sometimes when writing (never in speech, that I’m aware of).

Ultrafinitism and Infinity

A key question about reality is whether it is (numerically) real or merely rational. Part of the conflict between General Relativity and quantum mechanics is that the former has no limit on how small distances can be, down to some version of “infinitely small”. In quantum mechanics, the Planck length (1.616×10⁻³⁵ meters) is considered the smallest meaningful size and the Planck time (5.391×10⁻⁴⁴ seconds) the smallest meaningful time.

[In the paragraph above, I originally forgot the word “no” between “has” and “limit”. Only when I went back and read the sentence did it register.]

Related to this is the question of whether reality is finite or infinite. Both the real and rational numbers allow for infinitely small (or large) values, so this question is distinct from what number system applies to reality.

In any event, again from New Scientist:

Does this matter? Since the 1960s, a small but relentless contingent of mathematicians, philosophers, computer scientists and physicists have argued that, yes, it does. Calling themselves ultrafinitists, they warn against being overly trusting of numbers like 10⁹⁰ that elude our real-world experience. And don’t even get them started on infinity. “That is just an illusion,” says Doron Zeilberger at Rutgers University, New Jersey.
…
But 30 years after Gödel placed a bomb at the heart of mathematics, an unexpected character refused to simply wait until it exploded. Instead, Alexander Esenin-Volpin, a Russian mathematician, poet and dissident, claimed to have outlined a programme for proving the consistency of ZF theory. While only a subset of the ZFC rulebook, this programme still stood a chance of solidifying contemporary mathematics’ bones with an audacious trick: abandoning infinity.
…
Others draw inspiration from elsewhere. For Zeilberger, a computer scientist, the fact that computers can only ever approximate infinity – and so are unable to use the fuzzy “very large number” concept that humans rely on – is an argument for doing away with it. His affinity for ultrafinitism started when he first learned calculus, which uses infinitely large or small numbers rather heavily, to his distaste. The rise of calculus in the 17th century cemented infinity’s place in mathematics, but Zeilberger sees this as a historical fluke, a consequence of computers not having been developed earlier, and says that he would love to teach his students calculus without it.
…
Traditionally, mathematics is seen as a mere language for expressing physical truths, but some ultrafinitists go even further. For example, writing in 2013, Pavel Pudlák at the Czech Academy of Sciences argued: “One can, in principle, represent any finite mathematical structure by a physical object. Hence a theorem about finite mathematical structures is also a physical law.”

I have some sympathy for Finitism and even more for Intuitionism. I’m not sure I’m on board, but I can appreciate the impulse. I’m more inclined to a side between real and rational numbers — I have a growing suspicion that reality might be rational but not real (a phrasing that delights me).

Lucid Dreaming

I’ve managed to have only two strong lucid dreams that I woke remembering. They were incredible. I’m pretty sure I have a long history of semi-lucid dreaming. I’ve never suffered from nightmares, and it seems to have something to do with the ability during a dream going bad to say, “Hey! This is my dream, and I won’t stand for this!!” Usually, that wakes me up, but sometimes it alters the dream. But other than that moment of lucidity, the dream before and after was a usual dream.

Though my usual dreams tend to be very enjoyable, often vivid, generally weird.

Anyway, from Popular Mechanics (where Popular Science went to die):

The state known as lucid dreaming is an unquestionably surreal one, and it just got even more so. A team of researchers at Radboud University Medical Center in the Netherlands has discovered that lucid dreaming is a state of consciousness separate from both wakefulness and REM sleep (the state usually associated with dreams). In fact, it is associated with its own type of brain activity.

Huh. Cool.

Between Order and Chaos

Lastly, this interesting bit about the critical brain hypothesis (which I think makes a lot of sense). Again from New Scientist:

Researchers like Hengen refer to this idea as the critical brain hypothesis. According to them, our grey matter lies near a tipping point between order and disorder that they call the “critical zone”, or – more poetically – the “edge of chaos”. We can see the same kind of instability in avalanches and the spread of forest fires, where seemingly small events can have large knock-on consequences.
[…]
The hypothesis can predict the effects of mind-altering drugs and might help us to diagnose illnesses like Alzheimer’s with greater precision. It may aid us in understanding why some people are smarter than others, and perhaps it could even explain the purpose of sleep – and the origins of consciousness itself.

Most excitingly, certain meditative techniques may allow us to shift our brains towards or away from the tipping point – with the potential to enhance our mental flexibility.
[…]
Lying between order and disorder may also help the brain to adapt to new situations. “It allows the brain to be both stable enough to make sense of the world and dynamic enough to optimally respond to it,” says Jerbi. “We believe the brain operates near this edge of chaos because it’s the ideal zone for complex thinking, learning, decision-making and adapting to new situations.”
[…]
The enhanced flexibility arising from the critical zone could be seen in an experiment by cognitive scientist Jaana Simola and her colleagues at the University of Helsinki in Finland. The participants had to play a computer game that constantly changed its rules, which required them to update their approach on the fly. The closer their brains were to the critical point, the better they performed.

Jerbi suspects the brain’s proximity to the critical point may be especially important for creativity – a form of thinking that isn’t measured in standard IQ tests. “Creativity emerges from the brain’s ability to explore novel ideas while maintaining enough structure to make them meaningful,” he says. “Criticality may provide the optimal neural environment for this process, allowing the brain to shift fluidly between spontaneous, divergent thought and focused, goal-directed reasoning.”
[…]
Hengen, for instance, wonders whether sleep may have evolved to return the brain to its critical point. His studies of rats already provide good evidence that fatigue is intimately linked to the brain’s criticality. “The strongest predictor of whether or not an animal is going to be awake or asleep in the next hour is its proximity to criticality,” he says. “The closer you get to the critical point, the more likely you are to be awake. And the further you are from the critical point, the more likely you are to be asleep.”
[…]
In a paper published last year, O’Byrne and his colleagues found that the brains of patients under ketamine remained near the critical zone, whereas the brains of those who had taken xenon or propofol moved away from the tipping point. “This seems to suggest that brain criticality is a necessary condition for consciousness, though more work will be needed before we can say this with more confidence,” he concludes.

So interesting that I quoted a lot more than I usually do, but I wanted to include a number of important details. One interesting part of this is the role it may play in creativity. It would certainly explain why it’s hard to be creative when your mind is disturbed. Possibly also why, if you can get creative when disturbed, it usually calms the mind.

The part about sleep was interesting to me, too. The critical point seems involved in wakefulness — attention and focus.

Most interesting to me is that this is precisely the foundation and explanation of my guess that (true) free will exists (in advanced brains). Our minds imagine things constantly, and I think in the finely balanced order/chaos of our minds, we can freely choose among reasonably equivalent choices. The mental activity of a choice amplifies to action.

My canonical example is, having already decided to have soup for dinner, as I stand at my pantry looking at the various soups I stock, what makes me choose one over the other? That seems an almost entirely consequence-free choice, so what makes me decide on one?

But free will is a deep topic with no clear resolution so far, and I’ve reached my word limit, so that’s all for now.

§ §

Stay ultrafinite, my friends! Go forth and spread beauty and light.

∇