In this case, a very strong eruption ejects kids of super hot gas and rock upwards, like when you open a shaken bottle. After some time, pressure will decrease, and gravity will start dragging things down again.
Unlike a regular soda bottle, heat is significant. Hot gas rises in the atmosphere against gravity. During this rise, it loses energy ( so it cools down). When it reaches a high enough temperature where the lifting momentum is overcome by gravity, it starts falling again.
As the top starts to fall while there still is more material below in the column, the column gets compressed. As the center of the column is the hottest part, it still pushes material upwards. So the colder material falling from the top is pushed outwards, widening the column a bit. It also encounters the cold air outside and starts cooling even more itself, falling ever faster in the outside “ring” of the column. It still is only “cool” compared to the rising inner column, still thousands of degrees. Also, all the light glasses will have moved further up the atmosphere and either fall slower or not at all. This is where the long term effects such as your mentioned ash fall/ rain comes from. So most of the rapidly falling material that then form pyroclastic flows are actually fairly heavy liquids/solids and heavier-than-air gasses. They only seem so light and fast inside a pyroclastic flow because if their immense temperature and contained energy.
However, sooner or later the falling material encounters the ground, a solid obstacle. As the inner column is densely filled with super hot, probably still rising fresh material, the only possible way is outwards. And with continuous pressure from above from all the falling material, the material needs to move out of the way very rapidly. This is not dissimilar from how water behaves that flows from a bottle or faucet and hits solid ground. But a pyroclastic flow is a bit more viscous, and still very hot. While moving outwards, it quickly has to push away the cool, resting atmosphere. The only way for the air is to step aside upwards. Now, as the cold air likes to stay close to the ground and was compressed, it forms a seemingly paradoxical barrier layer of cold, dense air above the pyroclastic flow, pressing down on it, even squeezing it further outwards. This together with it’s own viscosity means there’s surprisingly little turbulence between the two layers, with the hot flow continuing to rush along below the cold barrier layer instead of mixing and rising through it upwards. If this interests you, look up inversion layers: they are a normal phenomenon in regular weather as well, especially winter time, and can sometimes even last many days.
Consider that ash columns reach many km in altitude, filled with many tons of material. It doesn’t all fall slowly at the same time. It’s literally rock falling from high atmosphere to the ground, carried by heavier-than-air gasses that also want to sit below the atmosphere.
Likely a person will, like livestock, put on less LEAN weight and be smaller in size. Quantity and quality water results in higher yields in all domestic livestock.
It’s all sorts of fish-related detritus. You can use your yucky fish water to water your plants and they will love you for it, fish pretty much poop finished compost. Like rabbits.
Because you’re ears evolved to hear sound in air. It’s an interface problem, not a transmission problem. Same with speakers and microphones, they are designed to be used in air.
So if you want to actually hear the sound, stick with air.
If you just want to transmit some information via sound, a dense solid like a metal will give you the best speed and distance.
I would say degenerate matter in a neutron star is a better conductor of sound. It’s densely packed and doesn’t have to deal with pesky things like electromagnetism slowing down the sound wave.
But, as far as resistance to UV and immiscability with UV resin, testing would be required, as I’m assuming you intend to replace the FEP film layer with a dense liquid.
Mercury? Isn’t it opaque and fully reflective? Or does UV light pass through it?
For initial testing, the FEP would remain, but as this liquid would theoretically not stick to the resin, the FEP would remain intact, pretty much eliminating risks that have anything to do with it.
I have seen something like this before, but it uses two different lightwaves in order to make the denser liquid remain inert, so it’s impossible to try it with consumer printers.
Ah, yes on the first count at least, though that criteria wasn’t on your bulleted list, I guess it was in the title.
That being said, UV breakdown might not be as concerning in the short term if the substance is removed fairly often. I wonder if a clear gelatin or glycerin layer would last long enough?
I’ve also seen resin-infused paper-like substrate layers of material like carbon fiber attempt to bypass the requirement of an FEP. Each print layer was a new sheet and once the print was done the un-cured material was blown away.
Assuming we’re talking about refractive index here, metals technically still have a refractive index despite being reflective (light can penetrate a very short distance through metals). In the UV, the refractive index of mercury is <1 and of course it’s very dense. But that’s probably not going to be useful to you.
For transparent materials, water actually has a lower refractive index than most liquids (around 1.34 in the UV). You can check this website to see if there’s anything better (probably an organic), but I doubt it would be by much.
I don’t know much about 3D resin printing, but I assume you a focus an image (in the UV) onto a resin layer to selectively cure it. As you suggest, the presence of a liquid would refract the focusing light rays and change the position of the focal plane. This could in principle be accounted for by changing the distance from the focusing optic, though there could be some (perhaps minor) blurring of the image.
@the_q@UraniumBlazer
I think the goal here is not properly defined.
A human is just a #brain , with a #body attached to it. The question is, how to keep this body healthy, so that our mind lives longer too.
Actually, if we have the ability to properly separate body from brain, do you know that our brain can live forever ?
So your proposal is transhumanism. Replacing the human body with something different. This is a very interesting discussion for futurology, but I am unaware of any advances in this field.
What kind of egomaniac thinks they’re so important that continuing to live is a good idea?
So if I break into your house and try to kill you, would you be an egomaniac to resist? If you get a heart attack and if you rush to the hospital to get yourself treated, are you an egomaniac?
Your mood and thought processes can affect your hormones and other parts of your body. Think of something scary, and you can make your pulse race and your palms sweat.
But if you get chased by a tiger, your pulse is going to race far more, and your whole body will sweat.
There’s no amount of thinking you’re being chased that equals the effect of actually being chased.
Additionally, working out causes muscle micro tears (from what I understand), which is part of the mechanism for building muscle. Like you said, no amount of imagination will produce the physical effects of exercise.
Getting jacked is a physical process that requires mechanical damage and healing to individual muscle fibres all over the body in every muscle (unless targeting specific groups only).
Placebo effect is possibly the result of people actively influencing their hormone levels and balance to encourage hormones that promote healing. Specifically increasing serotonin, that we know plays a big role in sleeping, which is where you do most of your healing. Serotonin also makes your entire food to energy pipeline function. More energy allows more energy to be dedicated to healing. Serotonin is also used to create ATP, which activates the muscle fibres.
So I would guess that you could probably increase the speed of getting jacked via placebo effect because your chemical balance is altered to promote serotonin. But you couldn't be sedentary and get jacked. And you could maybe not outpace someone else getting jacked if they're spending more time exercizing than you.
Disclaimer: I am not medically trained, I'm just someone who has been forced by circumstance to learn about the endocrine system and its tyrannical rule over organisms.
I rolled a natural 1 for END(ocrine function) in the womb and ended up with one of the comorbidities they didn't predict would be unfortunate with covid.
Unfortunately doctors know very little about hormones overall, which ironically makes it pretty easy to cover as a topic when researching possible ways to make your body do... the whole being alive thing. Serotonin happens to be one of the main hormones I'm tinkering with to try to partially unfuck what covid did to my brain.
The placebo effect has been shown to work even when the patient was told about it.
As in, the patient went in being fully informed about the placebo effect and it still worked.
And this weirdness also holds for the nocebo effect, where you get a negative/opposite effect that is out of character or excessive to the degree to which the treatment ought to fail or have negative repercussions.
It doesn’t do much, and nowhere close to what actual exercise will do, but it’s better than nothing at all by a small margin.
Iirc, the last study was done back around the turn of the century. I know I was still lifting at the time, and it wasn’t long into the noughts that I had to stop doing that seriously.
And, if my memory isn’t betraying me, it gives slight increases in benefits with exercise as well. I know that visualizing things in martial arts and other “muscle memory” activities improves performance of skills over not doing it.
Focusing on an idea in your mind regularly is literally mindfulness meditation, which has shit tons of research behind it improving people’s psychological and physical wellness
It does sound dubious, but there are good studies on it. You aren’t going make great gains, it just shows improvement that going without doesn’t. This is why it is also recommended to really focus on lifting and be mindful of the exercise you are doing.
Science has known for years that the fewer calories you ingest, the slower you age. Metabolic processes induce a lot of wear and tear.
As far as reversing aging, the protein thing may have some merit, but I would remain skeptical for now. My 2-cent guess is that truly reversing aging will involve some unholy cocktail recipe of stem cells, genetic manipulation using CRISPR, lots of fasting, and maybe some advanced vaccines (we’re learning vaccines can train the immune system to do all sorts of interesting things beyond fighting infections).
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