Dianna got better sometime last year as well, just in time to fly home to Hawaii for her father's funeral (yeah ...), but she got a lot worse again later. I really hope things will keep going well for Dianna now.
Props for her husband who's been incredible of taking care of her.
At the moment, she appears to be progressing up. The user you are replying to was talking about a past up-swing followed by a down-swing. Hopefully there isn't a down-swing to follow this current up-swing.
Such amazing news. She’s been bedridden due to long Covid. Got better a few times but after a while attacks came back. Both she and her husband showed great strength. So happy to see a new milestone.
thanks so much for the context. I'm glad if she's reclaiming from her losses <3
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 :'(
It's not the same photon though. The fusion happens in the core, then takes millennia for the energy to escape. During that time photons are emitted and absorbed by the atoms, until the surface emits one that finally travels to the earth in 8 minutes. Anyway that's taking you from the ELI5 to the ELI9 version. I'm sure someone on here can correct it further.
I haven’t tried to look up the history of this claim, but here are some guesses:
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.
I agree. I read the 5000 years time a few times and I don't like it.
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.
Any interaction between light and matter can be modeled as absorption and re-emission (stimulated or spontaneous) of photons. In this picture, there is not much difference between a photon traveling through the sun or through a piece of glass, and the analog makes physical sense. Since photons are massless elementary particles, they are indistinguishable and their number is not conserved. The notion of "the same photon" is questionable in any case.
Light from the sun that is reaching us now escaped the surface of the sun 8 minutes ago, yes.
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.
I think this is right in a certain sense, but not precisely. From what I understand no visible light photons are created in the core from nuclear fusion, it's mostly a bunch of gamma rays that get almost immediately absorbed. The energy, but not the photons from fusion, gets transfered up through the layers of the sun, through radiation and convection, eventually heating the photosphere. It is then the photosphere, white hot, which ultimately radiates the visible light we see as sunlight.
It's really cool to see her back and making videos again.
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.
I can't remember where I heard of it, but decades ago there was another neutrino detection center, also in Japan I think, that had those vacuum tube detectors, but care wasn't taken in systems design. One of them broke and the implosion caused the neighbors to break. Leading to a catastrophic of almost all the sensors! I feel bad for them, I'm sure someone here knows the exact name and date. But man, what a tough lesson to learn.
Edit: on another note, way to go on your recovery Diana. We've been rooting for you.
That was Super-K, the same detector she's talking about in the video. The incident occurred in 2001 and set back the start of the data taking for them quite a bit, they were able to begin data taking by re-distributing the unaffected photo-detectors to cover the gap where the imploded detectors were. Eventually (2005/2006) they replaced all the destroyed photo-detectors and took data from then on out with a full-suite of sensors. Following this incident all Japanese experiments with these types of photo-detectors take the risk of implosion seriously and have mitigation built in to the design. Super-K has been running continously since then with some interruptions for upgrades & maintenance, and is still taking data today (as far as I'm aware).
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.
Is this long Covid or depression or Major Depressive Disorder (MDD)? Because in her earlier videos she talks about becoming bed-bound again due to her emotional state after finding news her friend who had a similar condition died.
As someone who suffers from a complex autoimmune disorder which has caused dysautonomia and suspected mitochondrial dysfunction, stress flares and exacerbates symptoms. This has a physiological basis in the complex way the HPA axis/cortisol affects us at the cellular level. My primary diagnosis is sarcoidosis with small fiber neuropathy, but they don’t fully understand all the mechanisms of auto-immune fatigue and dysregulation.
Dunno, personally I don't think its that much of my business. Sure I'm curious, but that doesn't mean I have a right, or that its a nice thing™ to publicly speculate
Props for her husband who's been incredible of taking care of her.
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.
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.
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.
https://www.youtube.com/watch?v=vqeIeIcDHD0
(caution for those currently sick as it's a rough watch at first)
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.