Recent content by sylas

It's wrong because if you do the calculations correctly, as described by Einstein, you find that twin who went to a star and came back ends up younger than the twin who remains at Earth the whole time. It is also incorrect to think of time dilation as "illusion". It is not illusion. There is...

Some of those are terrible. But some are pretty good! Here are a couple I liked. The plan was simple, like my brother-in-law Phil. But unlike Phil, this plan just might work. He fell for her like his heart was a mob informant and she was the East River.

Um... a much more sensible conclusion would be that not everyone contributing is an expert, rather than "none of the experts agree". It can be good practice for a non-expert to try and identify the errors being made in so-called paradoxes or contradictions. The experts will generally provide...

cmb is cosmic background radiation; a useful reference against which velocities can be measured. You can't just add the durations from two frames, because that is assuming and absolute notion of simultaneity. This is invariably behind the confusions people have with respect to so-called...

Looks good. Further changes are cosmetic and probably don't matter. Well done.

You can't have y in your answer. That was a variable you introduced. There is also an error in your differentiation of a quotient, and another error later on in the simplifications. But you are on the right track.

Minor typo... there's a missing bracket in the second line, but the third line is correct so that's okay. If you use e on both sides you just get back what you started with. So that's no good. Try the other. Not sure what you mean by "implicit differentiation". Just differentiate both sides by x.

"I don't want to achieve immortality through my work... I want to achieve it through not dying." Woody Allen For myself... I know I have a finite duration; like pretty much everything else. This doesn't bother me. I know it doesn't bother me because about ten years ago I was given about six...

You are being cryptic -- and not only in response to me. I'm not bothering with this unless YOU make the effort to give a clear exposition of what you mean. A suitable translation into English of Einstein's famous paper On the Electrodynamics of Moving Bodies is available at the link. It does...

Yes, it does. Specifically, consider a star that is six light years from Earth, as measured in a frame where the star and Earth are at rest. Consider Earth sending a radio message to the star. I'll locate events using (x,t) co-ordinates (distance and time) in different frames, but I will keep...

Shrug. We all lose our minds and some point on the way to understanding relativity, or it feels like it. :tongue2: It doesn't last. Acceleration does have something to do with it, because acceleration is what causes the change in frame. Acceleration is not directly a cause of time dilation, but...

Here's a family shot from Sylas. My son is the good looking one.

Sure. I agree (since I think this is part of what you are saying?) that the resolution of this paradox can be identified unambiguously. It isn't actually a paradox, and like all the various relativity paradoxes, the solution is obtained simply by applying relativity correctly. If a paradox...

Yes, that's it! Using the title "bug and rivet", I had a look back in the archives. There's a good discussion of this particular problem from 2004 in the thread: What is the resolution of the The Bug-Rivet Paradox paradox in special relativity?. The last post of that thread, by Janus, also...

Not really. In the plunger frame, the plunger is significantly longer than the cylinder, because of length contraction of the cylinder. This means that the plunger reaches the end of the cylinder and presses the button well before the T-bar hits. As soon as you say they have the same proper...