Genady

Yes, this is clear.

It looks incorrect. Why the three points A, B, and C are on a straight line? And why A is in the middle of that line?

@martillo, The spacetime diagrams are good for qualitative comparisons between events and frames, but to get quantitative comparisons you will have to calculate Lorentz transformations.

And A? Wait, D is signal reception...

I understand that event D is "Observer C receives the signal". What are the events A, B, and C on this diagram?

If you are assuming this, then B and C are not symmetrical, and I can prove it. Since they are not symmetrical, when they meet their clocks and beards will not be equal.

Yes, this is the problem. But we keep trying not to let him do this . PS. I have to go now. We'll be back in about an hour, I think. Otherwise, good night to all.

OK, but note that it is not the same v that appeared in the Lorentz Jr's calculations. So, we got the diagram with observers B and C which meet at some event up there and with C moving toward B with velocity v. What else do we know? Exactly. But in B frame, C moves toward A slower than A moves toward B and yet they meet all together. Thus, C has to be closer to A than B.

If they are equidistant from A in A then they are not equidistant from A in B, at any moment in B. So, what is v? Velocity of which frame relative to which frame? C relative to B? Something else?

I think it will be better if you answer, make mistakes, discuss, and fix them. We already know that Lorentz Jr knows how to solve this. What midpoint? In B frame?

What is A?

The velocity relative to what?

What is v in the current formulation?

No, it does not. Why would you think so? There is nothing confusing about this diagram, unless one reads into it more than it shows. B and C on the diagram are not events. They mark world lines of observer B and observer C, i.e., the lines, one vertical and the other one tilted. There is no even a mark for t=0. The horizontal line is just a line of events simultaneous in B. I shouldn't even call it x axis, just x line. At some moment in B, the observers B and C are on this line, in the events where it intersects with the world lines of B and C. There is nothing to review, but there is a lot to add to this diagram. Better be done step-by-step. Poco poco.

I don't know what you mean, initially. It just shows that at some moment in B frame, they are on the x axis.

Yes. 5-10 minutes... @martillo:

If they are at some distance, then it is not an event. It is two events.

What about, e.g., an adiabatic process? No heat flow, but the temperature changes.

It stops rising when the He density inside the balloon equals the atmospheric. Not a pressure.

This scenario shows how it could happen. But: 1) Did it actually happen this way? 2) Is religion a necessary ("inevitable") or even the most probable outcome when starting with those innate capacities?

From the several examples there, I can see that they interpreted the result in that way, rather than found what they say they did. The same results can be interpreted in different ways. Are there peer-reviewed articles on these studies?

Are we? Maybe mysterious but why supernatural? Isn't the latter quite an abstract concept to be wired for? Maybe we are wired to assume causal relations or correlations even when there are none, e.g., black cat - bad luck, but I don't see a necessary connection between such assumptions and religion.

almost? When going from frame A to frame B, we use in the Lorentz transformation the speed of B relative to A. When going from frame B to frame A, we use in the Lorentz transformation the speed of A relative to B. These two statements are symmetrical. In fact, I've copied and pasted the first to make the second, and then have simply replaced A by B and B by A. How more symmetrical it can be?

Ah, I see. Yes, it is a thermal component of internal energy. It can change without any heat flow, though (in a reference to the OP).

Yes, it is. You're talking about enthalpy, right?