David Sinclair is an interesting person. I’ve seen him present his research in a professional setting and he does some really interesting science. He is also very enthusiastic at selling his story.
There’s likely no amount of supplement and drug cocktails that will undo the damage of a sedentary lifestyle and poor diet. Best case scenario is this research could be on to something that significantly augments a healthy lifestyle, or worse case it could be wasting a lot of money on something that potentially ends up being harmful a few decades from now.
I’ve looked at the list of supplements and drugs Dr. Sinclair takes and there is mechanistic rationale from cell culture and animal experiments behind the ones I’m most familiar with. But it is a big leap to go from cell culture and animal models to human health on a much longer time span. The clinical trials needed to really demonstrate a lot of these claims are incredibly expensive and would take decades. Drug companies in the anti-aging field tend to focus on older patients to start with and earlier endpoints like lower cancer, Alzheimer’s, or heart disease incidence. They also tend to be funded by silicon valley tech executives.
We already have computers that can determine which sounds to cancel out. That’s pretty cool.
Sound isn’t going to be like a bullet or an electrical storm hitting the grid. I don’t think you can just make a material that blocks out sound when it reaches a certain level and allow it below the threshold. Definitely an interesting theory but I am not sure how it would be designed.
Compression thickening/thinning, which only starts after a certain rate of change. I’m not sure what materials have such a property. Then, you’d incorporate it into a composite which dissipates sound selectively in one state. One idea is a fibers of a material that matches the impedance of the fluid during quiet periods, but scatters it as impedance shifts during high-energy periods.
Maybe you could use standard shear thickening somehow, but it would be a lot harder as sound only travels through air compressively.
Plasma is so low density, so the total heat capacity will be quite low. You’d need a lot of cold plasma to chill a very small amount of liquid water through freezing.
Remember that a plasma is an ionic gas, so it doesn’t have a specific temperature associated with it. It’s just a bunch of free charges (ions, electrons, protons). Assuming the bulk charge of the plasma is effectively neutral, then you have some limits on density. If they get too close to each other, they start binding to one another. At cold temperatures, it is much easier to collide and stick than at hot temperatures, so cold plasmas tend to be even lower density than hot plasmas.
Which means, it cannot absorb much energy, because there isn’t a lot of matter in it. Sure, you could cool something with it, but it would take a lot.
Most experimental research in matter under extreme pressures is concerned with recreating conditions within the interiors of planets and stars (this falls under the field of high energy density physics). The temperatures involved therefore tend to be very high. However, there’s no inherent conflict between high pressures and low temperatures, it’s just that temperature tends to increase when you compress something. Compress an ideal gas, for example, and it will heat up. Let it sit in its compressed state for a while though, and it will cool back down despite remaining under high pressure.
This is true for solids and liquids too (putting any phase transitions aside), though they are much less compressible. The core of the Earth will eventually cool too, though it’s currently kept at high temperature by the radioactive decay of heavy elements. Diamond anvil cells, however, can reach pressures exceeding those at the center of the earth in a laboratory setting, and some DACs can even be cooled to cryogenic temperatures. This figure on Wikipedia suggests cryo-DACs can be used to reach pressures up to 350 GPa at cryogenic temperatures. As an example, a quick search turns up a paper (arxiv version) that makes use of a DAC to study media at liquid nitrogen temperatures and pressures up to 10 GPa (~3% the pressure at the center of the Earth). Search around and I’m sure you can find others.
I would assume that the difference comes from the fact that the same intervals of light will correspond to intervals of different length when plotted by frequency vs when plotted by wavelength, thus making one of them appear higher, while the other is just wider
What I mean is that, for example, the interval from 1eV to 2eV has the same length as the one from 2eV to 3eV, yet they correspond to the intervals from 1/2 to 1 and from 1/3 to 1/2 (dropping units and constants), which have different lengths.
oooHHHhhhh! Then, does that explain why the wavelength one has a long skewed right distribution while the frequency one has more of a slope in the other direction if we adjust the scales to match the x-axis on colors?
I’m not fully aware of all the issues you reference, but my first guess is that oxygen is reactive and can be used up (apparently based on your statements, although I’m not familiar with that line of reasoning). Whereas nitrogen is not very reactive, so doesn’t get used up nearly as much.
I’m late to this, but I’d like to bring up something I haven’t seen anyone else mention. But first, some more details regarding what has been discussed:
In most situations, it’s correct to say that EM waves basically don’t interact with one another. You can cross two laser beams, and they’ll just continue on their way without caring that the other one was present. A mathematically equivalent scenario is waves on a string: the propagation of a wave isn’t affected by the propagation of another, even when they overlap. Another way to put this is that they obey the principle of superposition: the total amplitude at any given point on the string is just the sum of the amplitudes of the individual waves at that point. You may want to argue that the waves do interact because there are interference effects, but interference is exactly what you get when they don’t interact, i.e. when the principle of superposition holds.
However, this is only true for so-called linear systems. I won’t go delve too deep into the math of what this means, but I think looking at the wave on a string example can give you some intuition. The behavior of waves on a string can be explained mathematically by treating the string as a large number of tiny points connected by springs. If the force on a given point by a neighboring spring is directly proportional (i.e. linear) to the spring displacement (Hooke’s law), then you find that the entire system obeys the wave equation, which is a linear equation. This is the idealized model of a string, and the principle of superposition holds for it perfectly. If, however, the forces acting on points within the string have a non-linear dependence on displacement, then the equation describing the overall motion of the string will be non-linear and the principle of superposition will no longer hold perfectly. In such a case, two propagating waves could interact with one another as the properties of the wave medium (the “stretchiness” of the string) would be influenced by the presence of a wave. In other words, the stretchiness of the string would change depending on how much it’s stretched (e.g. if a wave is propagating on it), and the stretchiness influences the propagation of waves.
Something analogous can happen with EM waves, and has been mentioned by others. In so-called non-linear media, the electromagnetic wave equation becomes non-linear and two beams of light (propagating EM waves) can influence one another through the medium. This makes sense when you consider that the optical properties of a material can be changed, even just temporarily*, when enough light is passed through it (for example, by influencing the state of the electrons in the material). It makes sense then that this modification to the optical properties of the material would influence the propagation of other waves through it. In the string example, this is analogous to the string itself being modified by the presence of a wave (even just temporarily) and thereby influencing the propagation of other waves. Such effects require sufficiently large wave amplitudes to be noticeable, i.e. the intensity of the light needs to be high enough to appreciably modify the medium.
What about the case of light propagating in a vacuum? If the vacuum itself is the medium, surely it can’t be altered and no non-linear effects could arise, right? In classical electromagnetism (Maxwell’s equations), this is true. But within quantum electrodynamics (QED), it is possible for the vacuum itself to become non-linear when the strength of the electromagnetic field is great enough. This is known as the Schwinger limit, and reaching it requires extremely high field strengths, orders of magnitude higher than what we can currently achieve with any laser.
*I want to emphasize that we’re not necessarily talking about permanent changes to the medium. In the case of waves on a string for example, the string doesn’t need to be stretched to the point of permanent deformation; non-permanent changes to its stretchiness are sufficient.
It’s called a photosystem and theirs 2. Just search up photosystem. The first one is actually the second one and the second one is actually the first one.
People are inherently bad at rating things. Why not run a “This or that?” style study instead?
Given a list of items to rate, pair them up randomly. Ask a person which item they like better out of each pair. Run through Final Four type eliminations until you get down to their number one preference.
Run through this process for each person, beginning with different random pairings every time.
Record data on all the choices - not just the final ones. You should be able to get good data like that.
For example, there will probably be a thing that is so disliked that it gets eliminated in the first round more frequently than anything else. The inverse will likely be true of a highly-preferred item. And I am sure you can identify other insights as well.
Sounds like a good idea, however my participants neither have the attention span nor do I have the resources to do anything else :) after all, like I said, it’s just a small personal thing :)
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