Recent content by Gumby The Green

I understand the conventionality of simultaneity, but it has no physical consequences and thus isn't relevant here. What matters here is the relativity of simultaneity, which is determined by relative motion, not convention, as that paper explains. And as it quotes Poincare as saying, "The...

Well of course I'm assuming that the cabin's front and back door are both open, that the bunk fits through them without touching them or anything else in the cabin, and that the bunk's trajectory allows it to fly through both doors.

I see. Well I could use a term like "observational frame", like that Wikipedia article does, to specify that it's type #3. But isn't it just implied that that's the case when someone speaks of the frame as belonging to an observer?

True but they're the right ones to use if you want to know whether Bob's bunk will fit inside Alice's cabin for a brief moment while it flies through it (like in the ladder paradox), right?

This aligns with what I understand. It sounds similar to the concept of proper time. I was tempted to call it "proper length" but then realized that there's a subtle distinction: proper length is the length measured in the rod's rest frame, but you're saying that the measured length of the rod...

I don't think you've understood what I was arguing for. I was saying that during his acceleration away from the Earth and the distant observer—who is farther away from him than the Earth is—he would believe that the time of that distant observer runs backwards relative to his own. But note that...

I realize that. I just made the events “equidistant” from me in my example for simplicity.

If light from two equidistant events reaches my eyes at the same time, I say those events are simultaneous for me. How would it make sense for me to judge simultaneity any other way? Regardless of the answer to that question, if I apply that method consistently in every frame I find myself in...

[SIZE=16px]But again, can’t the distant observer see the falling observer forever slowing down and becoming more red shifted as they approach the event horizon? I’m not talking about global simultaneity; I’m only talking about simultaneity for a distant observer that’s stationary relative to the...

But isn't it true that it does take infinite time in the frame that treats the distant observer as stationary—which I'll simply call the frame of that observer for brevity—and finite time in the frame of the observer who's falling in? And aren't these effects measurable for each observer, e.g...

I don't see what that has to do with frame dependent quantities. I don't have to adjust the length of my ruler in order to measure different lengths for a rod in different frames.

I think I understand what constitutes a valid coordinate system, and I won't mention backwards time again until we iron out the issues that are keeping us from talking about it constructively.

I completely realize that they're frame dependent quantities and that there's no contradiction in the fact that they're measured differently in different frames. That's exactly what I was just explaining in detail. When I say that an effect is physically real in a given frame, I'm just saying...

I'm not ignoring your points Dale; I'm thinking through them. In a number of my comments, I'm just clarifying points I've made or showing why I think that someone's refutation of one of those points fails regardless of whether the point is true. So my rebuttals to attempted refutations of my...

Ok, here's what I'm not understanding about that: Relative motion causes relativistic effects that can include measurable physical effects that differ depending on the frame. For example, a rod has different lengths in different frames, and a charged particle produces different magnetic fields...