this post was submitted on 19 May 2025
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[–] [email protected] 27 points 3 weeks ago

Probably worth mentioning that this is not some kind of barely percetible flash of light that is emitted as an organism expires.

... What it actually is, is a variety of different metabolic processes emit extremely weak photons as part of the various chemical reactions involved in keeping a living thing alive... and so when that thing is dead, those metabolic processes cease.

[–] [email protected] 11 points 3 weeks ago (1 children)

This reads like how we used to think that the body got lighter when we died due to the soul leaving the body. Turns out we just exhale and fart a lot after death.

[–] [email protected] 5 points 3 weeks ago

Also lose a lot of liquids.

[–] [email protected] 6 points 3 weeks ago

Anything that's warm emits light, both organic and inorganic.

https://en.wikipedia.org/wiki/Thermography

[–] [email protected] 6 points 3 weeks ago

I think to myself, light is a form of radiation and the human body is really just a super computer but biological and it runs off of electrical chemical processes so I don't know our interpretation of things are still valid, yet not understood. So, I could just accept that as a statement. Poetic artistic interpretation.

[–] [email protected] 2 points 3 weeks ago (4 children)

Interesting. I wonder if humans can subconsciously pick up on it. Supposedly humans can often subconsciously detect when someone else is in the room through tiny vibrations in the air. There is definitely some visual quality that separates a dead person from a live one, but I personally think it's something with the pupils. It'd be cool if it was miniscule traces of light, though.

[–] [email protected] 6 points 3 weeks ago

The paper itself says "The phenomenon of biological ultraweak photon emission (UPE), that is, extremely low-intensity emission (10–103 photons cm–2 s–1) in the spectral range of 200–1000 nm, has been observed in all living systems that have been examined." Human vision falls within that spectral range, but the brightness is several orders magnitude too faint to see with the naked eye, even in absolute darkness.

[–] Timecircleline 3 points 3 weeks ago

It's the stillness. It's there even when the pupils aren't visible, although there are some changes with the eyes after death (tache noir comes to mind).

[–] [email protected] 2 points 3 weeks ago (2 children)

I've noticed when pets die that they appear dim and grey afterwards. Not just their skin and eyes, but also their hair. It's an immediate change. I've always thought of it as the light going out of them.

[–] [email protected] 8 points 3 weeks ago

Animals are very rarely completely still. Even the motion of breathing or their heartbeat is enough to create very slight motions. This causes their fur to subtly move and shimmer. Our brain evolved to spot things like that (spotting prey, or predators). It's piped into the conscious mind without context however. We just get a visual "something is missing/it's fake" message.

[–] [email protected] 4 points 3 weeks ago (1 children)

My cat died in my arms. I woke up. I thought he wasn't real.

[–] [email protected] 4 points 3 weeks ago

That sounds like a terrible surprise. I'm sorry.

[–] [email protected] 1 points 3 weeks ago

You know, people come up with all types of interpretations, but there is something to it.