Boltzmannbrain

That is what a lot of people think. It actually slows down. This video explains it perfectly,

Actually, the speed of light is slowed by the environment that we are living in. The speed of light slows in the presence of electrons, which are everywhere. The real speed of light is in very spall spaces if it exists at all.

I read that you did not want the distance from B to A to equal the distance from A to C, but this diagrams shows exactly that. If you want to understand Spacetime diagrams, you should get familiar with the Minkowski metric, if you aren't already. This is the metric you have to use with spacetime diagrams. It is just like a 4 dimension Euclidean metric ds2 = db2 + dx2 + dy2 + dz2, but you will see that the time vector is negative in this Minkowski metric which is ds2 = -dt2 + dx2 + dy2 + dz2. The negative sign only matters at angles more than 0 degrees from the point that you want to know the distance to because -dt2 = 0. Then in the case of spacetime diagrams, you just have ds2 = -dt2 + dx2. And in the case from B to A or from B to C it is just ds2 = 0 + dx2 So, as you see in your graph, from B to A and from B to C, you would use just the normal Euclidean/Pythagorean metric. Knowing this will save you a lot of pain and frustration, especially as angles are more than 45 degrees. For angles more than 45 degrees, you have to totally through out all intuitive notions of distance and angles. For example, the angle that B and C make with F is not Tan(opposite/adjacent) like we were taught in school. And the distance from C to F is not found using Pythagoras a2 = b2 + c2, also like we were taught in school.

Yeah, I had a feeling this was a motivation. Thanks for the backstory.

I have been reading this whole time, and as much as "destroyed" is bizarre and possibly outdated description when heat energy is converted into work energy, the term "destroyed" isn't necessarily wrong. If there is any possible argument left here against the OP it is that mainstream physics today does not describe such a process this way. Maybe for some reason "destroy" had different connotations 100 years ago than it does now, especially since the term "energy cannot be created or destroyed" is such a widely known and used phrase.

Yeah, I think you nailed it. I was looking around and I saw something that reminded me what I learnt a long time ago. F = ma actually means a net force = ma. And net force is a change in momentum over a change in time. See, 5.3 Newton’s Second Law – University Physics Volume 1 (ucf.edu) (see lower part of webpage for reference). So I think momentum is crucial to this problem too. In that case, I think the issue that the OP had with force is that the air particles with seemingly no acceleration (even though there is acceleration) needs more than just F = ma to explain what is happening. So, momentum, as you pointed out, is one of the major factors here.

Yes, I agree. The OP, as I understand it, is confused about what F = ma means regarding the scenario given. It reads as if the air is not accelerating and therefor can't cause a force. But like you say, F cause m to a. And really, I suppose that the air is accelerating, in the negative direction, from the force being applied to it from the wall. It might make more sense for the OP to know that Fwind = - Fwall , which is from Newton's 3rd law.

To make it easier to imagine fundamentally, we can make the air one big point particle and the wall one big point particle too. What is happening? The air (let's call it a gigantic oxygen molecule O2) travels towards the wall particle (let's call it a mix of molecules called W) and as it gets closer and closer there is a repulsive force (from electrons that surround both O2 and W, but that is not important), an equal and opposite reaction occurs. Eventually, if the wall breaks, that means that the W molecule/wall gave and accelerated in the direction of the O2. Or, if the wall does not break, then something had to give, namely the Earth. Ever so sightly the Earth had to accelerate and gain momentum (this is from the law of conservation of momentum: the O2 must transfer its momentum).

Wait everyone. From what I understand F = ma doesn't mean that ma causes F. It is just that F is equivalent to ma. And the air would not be the F or ma; the wall is. The wall's acceleration is how we would find the force caused by the wind.

Yes, thanks, but my math stops after first year university calculus and linear algebra. I was hoping just to get a basic visual/mechanical understanding of how this worked, and I think I got it by visualizing the two waves combining. I appreciate your help!

Thanks everyone. From what the seems to be saying, I am gathering that the light wave and the wave from the electron combine into another wave. Moreover, the wave of the electron speeds up and the light wave slows down, which makes sense energywise. Is this kind of the just of what he is saying?

This video is trying to explain how an oscillating electric field of light interacts with the oscillating electric field of electrons as the light passes through a material. He seems to be saying that the wave from the electron is slower than the light wave, and when they combine, the light slows down, though he doesn't say that explicitly. So my question is: wouldn't the waves of the electric field of electrons also go the speed of light? If not, what speed does it go? Start the video at about 6:20 when he starts to explain what I am trying to understand.

But doesn't it "expand" and "contract" at the speed of light? That is kind of like moving isn't it?

This is a fun question to ponder. Does anyone know if there a scientific definition of spacetime? I have never come across one.