Recent content by Dragon27

I think, there was two different experimental set-ups in this thread. In the original post there was a set-up with only a single photon, and then later in the thread TS introduced a second set-up with two photons emitted in two opposite direction from the same point the way you described. I...

I see two possibilities here: a) the student believes that "simultaneity" is a property of an event (by itself), not a relation between two events, b) the student didn't accept the assumption that the simultaneity relation is symmetric (A can be simultaneous with B, while B is not simultaneous...

I'm an autodidact and I think it worked very well for me as an autodidact. It's more verbose and friendlier on the explanations than Morin and the problems are easier. It still has the usual stuff like basic Newtonian formulation (and things that follow from it, conservation laws, etc)...

I found Taylor's Classical Mechanics easier than Morin. But Morin is good, you should do it when you feel ready.

I'm not sure what does 'why' have to do with definitions. You can ask why some force appears and acts in some way, but you can't ask 'why' to a definition, it's just a definition. That just how we define tension, and then we try and see what we can derive from the definition. Or maybe you mean...

Yes, that is exactly what I meant, I just didn't want to mention terms like "time-like interval" and "causally connected". The light flashes on the moving train (where P' is located) are separated by a time-like interval (as are any events that happen on a real moving body, that we can consider...

Yep. And of course the light from B will hit them after the light from A. That what happens from the point of view of the observer P (the one in the middle of the platform), and this sequence of events (i.e. the order of lights flashing on P') should not depend on the observer.

When you say "P' observes" you mean "light from the event reaches P'", when your colleague says "P' observes" he means (whether he realizes it or not) "event happens in the frame of reference of P'". In other words, P' sees the light from the event and then calculates backwards when the event...

There's also an interesting introductory book, Fat Chance: Probability from 0 to 1. Here's a review on MAA https://maa.org/press/maa-reviews/fat-chance-probability-from-0-to-1 MAA also has a review for Morin's book: https://maa.org/press/maa-reviews/probability-for-the-enthusiastic-beginner

Why would it? The light will travel less far with respect to the moving clock (i.e. the vector movement of the light minus the vector movement of the clock), which indicates that the moving light clock is ticking slower. If the clock was shrunken in perpendicular direction to compensate for...

What is he actually trying to say/motivate in these short videos? Has he actually mentioned that (in some other videos)? He probably thinks about some well-known ideas from math, but since he is conscious of talking to a layman audience he doesn't state them too explicitly, because the audience...

How do you define angle measure?

But you still have a lot of work to define angles rigorously. Analytical definition of sine/cosine is, imho, comparatively less effort.

Well, tbh, I felt encouraged to try and probe more into the assumptions of the question by the fact that the assumptions were more guessed at, than clearly stated, and by this statement:

Yes, it makes sense to relate back this new analytical definition to your previous geometrical intuition, which was not really rigorous (and developing rigorous geometry with angles and stuff so that you can define trigonometric function from the start is quite difficult, and it is much easier...