> in the spectral range of 200–1000 nm
That's UV, visible and near IR. We know that 100-600 nm (infrared EDIT: UV) light "can carry out photostimulation and photobiomodulation effects particularly benefiting neural stimulation, wound healing, and cancer treatment" [1]. I'm curious what could be producing UV and visible light.
Does light production tend to hang out around any particular organs or organelles? If stress causes it, I'd hypothesise it's metabolic or signalling related.
Ultraviolet, you mean.
> I'm curious what could be producing UV and visible light.
There is tons of chemoluminescent stuff in a live being. As my spectroscopist friend says, everything luminesces at some point.
This likely then leads to redox transitions in quinones, flavins, metal centres, leaving them in unstable excited states. When they relax, the excess energy has to go somewhere - usually thermal energy, but just occasionally, a photon.
This would also tally with anaesthetics and injury having an effect, as both effect mitochondrial function - and of course when you’re dead, so are your mitochondria.
For the next decade it most probably will be one of the very important topics in science of life in general.
https://en.m.wikipedia.org/wiki/Black-body_radiation
You can see it in the picture, the radiation is very wide.
I was pointing out that literally everything we see is the result of that object emitting energy which our eyes then sense
(The near infrared range corresponds to the typical energy differences between different vibrational states of the atoms in a molecule. Such energy differences are smaller than the energy differences encountered in most chemical reactions, which involve extracting or adding atoms from/to the molecule, which obviously needs more energy than the vibration of those atoms, when they remain bound in the molecule.)
Thus it is normal and expected that the output molecules of an exothermic chemical reaction may be in an excited state from which they can decay to their ground state by emitting light exactly in the visible range.
As long as it is living, in any organism a lot of exothermic chemical reactions happen. In many cases the energy produced by those reactions is used for something useful for the organism (i.e. the excited output molecules transfer their surplus energy to other molecules), but it also may escape as emitted light, reducing the efficiency in the use of the energy produced by an exothermic chemical reaction to less than 100% (the efficiency is also reduced when the energy of the excited molecule is transferred to other molecules than those intended, which eventually results in warming the environment instead of doing useful work).
So you're saying that there is something special about the visible spectrum? I've always wondered why most eyes we know of work in that range (modulo some leftovers from our time as aquatic creatures)
https://www.sciencedirect.com/topics/physics-and-astronomy/s...
However the causal dependencies are more complex than this. If the available light would have been from another range of the possible frequencies, the eyes could not have used the same kinds of photoreceptors that are used now in the eyes of all animals.
For instance, if the available light would have been only infrared, then photo-chemical reactions could not have been used for detecting it, but such light could have been detected by its warming effect, like some snakes do for detecting infrared.
If our star would have been much colder, with negligible visible light, then such light might have been not usable for splitting water and generating free oxygen in the atmosphere. In such a case, the planet would have remained populated only by anaerobic bacteria and viruses, like in the first few billion years of Earth's history.
It's also special for a few other reasons. The most obvious one being that UV light is destructive to many forms of animal life, there isn't much utility in being able to see for example something like X-Rays. They don't occur naturally in any quantity and the mechanisms that create them (lightning) also give off visible light.
On the other end of things, lower energy photons are what we would call heat. Some animals can see it, but not humans. We can sense it just fine through other mechanisms however.
* Meaning "molecules containing carbon", not "hippy chemistry done without pesticides".
Of course visible light is visible because it hits our eyes (is emitted by sun and is not filtered), but the comment about valence shells is quite a bit more fundamental than that.
This finding is certainly interesting, but it does not at all contribute to "spiritual thinking".
Here you are saying that some unspecified group is deriving some unspecified ideas which are, you claim, life riskingly serious.
Just for the sake of making HN interesting to read, can you stop with the one sentence comments that vaguely imply you know something we don’t, and be more exact, explanatory and specific?
Or, yes, under ideal conditions, maybe sometimes. 51.6% chance of being right in a yes/no question will not help in this case.
Human bodies are different in many ways.
People can pick up single photons, this is definitely within the realm of possibility.
Btw, your level zero snark can be defeated by the "on which planet?" argument.
But we already have plenty to think about.
The thinking that preceded our current understanding of physical elements was very loose and woo-woo(Water, Earth, Wind, Fire), but we refined.
I guess it's a charged topic for me (badumm-tss).
That said, this light is not the result of just radiating heat and must have a different source.
So probably invisible but under the very darkest of conditions?
This point is addressed on page 2 of the paper.
Paper is accessible on bioarxiv: https://www.biorxiv.org/content/10.1101/2024.11.08.622743v1
This is specifically not thermal (blackbody) radiation, which is negligible at the visible frequency range for mice at these temperatures. The researchers find a difference in visible wavelength emission between living and dead mice at the same temperature
This point is addressed on page 2 of the paper, accessible on bioarxiv:
Also strange: The effect changed w/ injury or anesthetic treatment according to the abstract.
“Aura scanners” has an appropriately cyberpunk feel.
They note increased emissions due to injury, which would be consistent with repair activities increasing the general intensity of chemistry happening to facilitate repair at wound sites.
https://www.youtube.com/results?search_query=microtubules+co...
Skeptic meter caught fire before I could get a reading.
Joe Rogan has interviewed plenty of people, different people that have very little in common, just because some of them have controversial views that make you nervous that doesn't mean all the information is useless.
Or are you rather shielding from whatever makes you think?
>And you're enough of an expert on all subjects to judge?
Never claimed to be
https://www.youtube.com/watch?v=QXElfzVgg6M
https://pubs.acs.org/doi/10.1021/acs.jpcb.3c07936
https://www.sciencedirect.com/science/article/pii/S157106452...
The whole thing is good, but the final punchline in the last three panels are particularly relevant.
The effect changing with injury or anaesthetic I guess reflects the fact that there are different electrochemical processes occurring in these cases that have detectable differences in the photon emissions
But this is independent of the misconception that the radiation observed in this experiment is thermal. Thermal radiation in the visible range at this temperature is much lower in intensity than the biological radiation observed here, but both kinds of radiation are well below the intensity that we can see with our eyes.
I should have added that this result wasn't unexpected or mysterious as it might sound, because it's known from physics that different chemical processes have characteristic photon emissions. Since it's known that different chemical processes occur in living and dead organisms, it was expected that there would be differing emissions in the two cases. As far as I know this research is the first actual detection of these differences
Animals (and plants? Bio 101 was a long time ago) use ATP for a lot of their metabolism and phosphates are pretty well known for emitting light as they react.
https://news.northwestern.edu/stories/2016/04/radiant-zinc-f...
I didn't yet have the patience to go through the original research papers to see what the manner of detection was (I've had a couple of drinks this evening), but the phrasing of zinc "sparks" suggests emitted photons. On the other hand, the fact they're talking about zinc rather than photons suggets they're talking about detecting ion transfer rather than photon emission
Here are articles commenting some of the content:
https://nrc.canada.ca/en/stories/worlds-first-ultraweak-phot...
https://www.sciencealert.com/we-emit-a-visible-light-that-va...
https://phys.org/news/2025-05-emit-faint-extinguishes-death....
Another problem to solve though, is ignoring the E-M radiation from small life forms that may be in the room.
The fading of the light would be sufficient but not necessary for someone to be considered dead, so it would make a poor definition.
https://medium.com/@lukehollomon/anesthesia-works-on-plants-...
usually unintentionally pushing the accepted narrative
anytime something interest comes up everyone seems to try to downplay or explain it
the fact is even your explanation is wrong on some level
https://static.publiclab.org/#wiki/ndvi
The difference here being absorption vs. emission I guess?
- Yoda
Still makes you wonder if your carrot on the counter still has any? The juicers will say that it does but if you cook the carrot it won't.
It is usually taught in school. /s
gnabgib•4mo ago
Previously (19 points, April) https://news.ycombinator.com/item?id=44617867