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Note that the “index” on the first page of the notebook PDF I just posted about above doesn’t work. Just scroll down or go to the next page in your PDF viewer. Sorry about that.

I’ve also posted some pictures that I might put up while working a couple of the problems. You might want to download this PDF in advance. When I tried sharing my Zoom screen with these they looked a bit hard to read.

I just posted an answer sheet up above. I had meant to spend more time on this, but I decided it was better to get it up there so that people could compare their answers to what I got. I doubt we’ll have time to work all the problems on Sunday. So between this and answers that other people post, when Sunday comes we can concentrate on whatever…[Read more]

Yes, if you have time that would be good.

Would you like us to post solutions here?

Clarification on problem 6

We are looking for a frame where the two events will occur two seconds apart in time.

In other words, we’re not trying to contract the 3 light-second spatial distance. We’re trying to find a frame where the time between the events is two seconds. This is not a simple dilation or contraction problem.

The second problem set is posted above (and I’ve also posted the slides and the video in the thread for yesterday’s meeting).

Video and Slides posted above.

Posted Scott’s slides above.

Video (and the notebook with the pictures I used) posted above.

I’ve uploaded the video, and I did the best I could to export the spacetime diagrams from that python notebook. There a link to them right after the link to the problems and answers (up above).

I made some corrections to the answer sheet and posted it on the September 7th meeting page.

You are correct! In my response to you, by t0 I just meant proper time (which is also t’ in this case). I completely see that the reduction works here, I feel I’m getting closer to having an intuition about when such reductions to proper time/length calculations are allowed (seems to be: whenever one event is set at the origin and is then compared…[Read more]

Mike, our answers match except for round-off error.

If we want to be picky:
1. For problem 1, our only difference is that I used 3 significant digits instead of your 2.
2. For problem 2, we took different approaches but I think either is valid, and our answers are off only due to the slightly different values we got for #1 (roundoff error).
3.…[Read more]

@john, @scott I put my first cut at the answers here. I’m not going to post them as the official answers until either Tina or one of you guys agrees with them. But have a look. I don’t think these all match either of what’s above, but I haven’t actually kept up on the conversation. Sorry!

I’m thinking that we’ll have a session to go over these…[Read more]