The atmosphere sure changed a lot because of life, which might have had its effects on incoming solar radiation? Which might have changed the temperatures of some ocean currents/continental plates? I don’t think it would differ significantly
I had access to a laminar flow hood at work, so I cleaned the dust off my phone and installed a new screen protector inside it. That was the best screen protector installation I ever did. Being able to ensure you’ve removed 100% of particles from the screen really makes a difference haha
I think I read somewheres that you need 240Hz monitor to reach flicker-fusion with parrots?
It was either 120Hz or 240Hz.
I lost flicker-fusion one time in a movie theatre when an onscreen character pulled a knife, & suddenly the screen was AVALANCHING my mind with discrete-frames, & they were jumping around ( my eyes were jumping-around, but my perspective, within my brain, had been jarred ). That even seemed to have lasted about 1 second.
There is some video, journalism or documentary or something, on dragonflies, and the person with the knowledge was saying…
~ we know how long it takes for each layer in a brain ( neural-network ) to process its layer’s stuff, and we know from the short reaction-time of dragonflies that they’re using 3-neurons-deep brain for navigating/hunting/reacting.
We don’t know how. ~
I seem to remember that neural-signal in our biology runs at about … 300km/h?
Something like that.
So, with all the circuitry being shorter in an always-smaller kind of animal, it may have a predictably-shorter flicker-fusion rate?
( within kind, so no extrapolating from humans to birds, e.g. )
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.
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.
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