(www.youtube.com)
Props for her husband who's been incredible of taking care of her.
Hopefully she maintains a higher baseline from here on out and the production of these videos doesn't produce further Post Exertional Mailise that could worsen her condition.
i want to be more appreciative every day for my health post-covid... not everyone was so lucky, and I can only imagine the gut-punch it is to know everyone went through a thing, but you got singled out for some perpetual daily punishment :'(
I’m today years old learning that the light that we actually see on earth today came out 100s of thousands of years ago.
1. There’s a sort of diffusion process going on. Photons from the core have some mean free path as a function of radial position (and, obnoxiously, of wavelength as well, so maybe we ignore that). You could calculate the mean time for a hypothetical object emitted from the core and traveling according to those mean free paths to escape.
2. You could imagine you have marked a photon and watched it travel. This is quite problematic. First, photons in thermal equilibrium obey Bose-Einstein statistics because they are indistinguishable bosons, and anything that could mark them would change the statistics to that of distinguishable particles. But whatever, the temperature is high and maybe this doesn’t matter. Also never mind that those core photons are mostly much shorter wavelength than the photons we see. But you can still imagine. (The answer is probably quite similar to #1 since this is sort of the same problem depending on how you think about the interactions with matter in the sun.)
3. You could calculate how long it would take to notice anything if the core suddenly stopped fusing.
When you have a transparent medium like water or glass, the photon that enters and the photon that exit share a lot of properties, in particular energy/color/frequency. Perhaps they have a shift in the phase or a different polarization (like in water with sugar or if you want to be fancy a quarter wave plate). You can still split a beam before in enter and make interference experiments after half of it passed though water or glass, and other weird experiments, so I think it's fair to call them "the same photon".
But in the Sun, the original photons in the center of the Sun have a few very specific values of energy/color/frequency, that are totally lost. (But the neutrinos have so few interactions that they don't lose this information, and it's possible to do neutrino spectroscopy!)
Also, the photons emitted by the "surface" of the Sun have a wide spectrum of energy/color/frequency that is very close to black body radiation at something like 5000K-6000K.
So in my opinion it's better to think that the original photon in the center is absorbed shortly after it's emitted, and transformed into heat. The heat takes 5000 years to get to the surface. And then the hot surface emits a few new photons unrelated to the original one.
I'm not sure what is the main transmission method inside the Sun: conduction, convection or radiation.
[0] https://scholarship.haverford.edu/cgi/viewcontent.cgi?articl... Eq. 16 [1] Handy plot at https://commons.wikimedia.org/wiki/File:Quantum_and_classica...
> You could calculate how long it would take to notice anything if the core suddenly stopped fusing.
FW(little)IW (very not my field, just AI, quick&sloppy), for a Sun magically switched to contraction-dominated heating, I'm sloping order 10^6-7 yr for a 1% increase in surface temp, with core contraction dynamics being just one uncertainty.
However, as the photon collides with other particles during its random walk, some of its energy is transmitted to those other particles. Sometimes a collision transfers energy to it too.
In a simple model, the energy that originally belonged to the photon gets transmitted from particle to particle through convection, and can escape the star through radiation long before the original photon reaches the surface. I don’t think that model is supposed to be physically accurate, rather to be an illustration about the convention process inside a star.
But photons are generated in the core through nuclear reactions, where they take their sweet amount of thousands of years bouncing around until they get out.
Her back catalog is good and you still get paid for people watching your old videos.
Thirty interactions on average per day, that's crazy - earlier in the video the host mentions that the cross section of a thumbnail has a billion neutrinos flowing through every second!
However, looking for sources relating to leaching by ultra pure water (UPW) not much turned up.
I did however find on Google Scholar a paper "Ultrapure Water: friend or foe?"... which lead me to https://www.balazs.com/sites/balazs/files/2023-03/pub0039-up... . Reading between the lines, Marjorie Balazs appears to have made a career out of UPW; she says in that paper:
"The ability for UPW to absorb and dissolve or react with all kinds of materials complicates other aspects concerning its use in the processing of wafers."
Seems like UPW dissolves anything, so lends credence to the anecdote.
Interesting topic, hadn't thought about UPW for wafer fabrication before.
The chain reaction escalated uncontrollably, and within ten seconds, approximately 6,800 of the 11,129 PMTs were destroyed.
[1]: https://physicscommunication.ie/neutrino-detector-in-peril-t...
After seeing her status updates 2 years ago I was honestly really concerned she would be gone for good. It sounds like she had a serious case of myalgic encephalomyelitis brought on by Covid.
Part of why we know so little about these types of conditions is they are incredibly unfair. Women are 4x as likely to have some sort of constant fatigue disorder as men, and you see this reflected in literature going back centuries when describing women who just flat out disappear from public life.
One of the things about being bedridden for a long period of time is that there is a high risk of becoming more or less permanently bedridden. Especially if you have a chronic fatigue syndrome, you become weaker and any activity can retrigger fatigue. So her pushing herself to make new content sustainably is important very encouraging.
This is because the electromagnetic energy of the supernova can take hours to force its way through all the star's mass to the surface when the core dies, but the gravitational crush turning protons and electrons into neutrons releases a massive burst of neutrinos in every direction. And the neutrinos are so weakly-interacting with the matter in the star that they get out first. Then, a million years later, arrive in our solar system at such a high fraction of lightspeed that they presage the coming electromagnetic shock-front because the constant difference in escape time between neturinos, which are particles of matter, getting out of the star without interacting with anything and the electromagnetic waves moving through the star's matter at a fraction of lightspeed created a gap that the light never caught up to.
The universe is a profoundly wild place.
Edit: on another note, way to go on your recovery Diana. We've been rooting for you.
Construction is underway on the next version of the experiment "Hyper-Kamiokdande" which is similar in design but significantly bigger. If I recall correctly Hyper-K will be two 200 kilo-tonne detectors, compared to Super-K which is a measly 50 kilo-tonne detector.
https://www.youtube.com/watch?v=vqeIeIcDHD0
(caution for those currently sick as it's a rough watch at first)