PeterDonis's latest activity
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PeterDonis reacted to DaveC426913's post in the thread I I don't see how a black hole's event horizon can be crossed with
Like.
This is worth repeating, I think, so as not to discourage the OP: He may not be getting he answers he asks for, but it's not because... -
No. It's showing accumulated time of his clocks minus a lab clock (hence the vertical axis being "residual phase"). The comparison is...
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PeterDonis replied to the thread B Project GRE^2AT - GR on Mt. Ranier.Yes: he was up there for "a full two days". Your result is ns/day, so you need to multiply by two. :wink:
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PeterDonis reacted to Dale's post in the thread I Variation of the lightning train thought experiment with Like.
Length contraction is the comparison of a length in a frame where it is at rest vs the length in a frame where it is not at rest. Light...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.The correct premises are the black hole models that have been built using GR. Understanding them requires taking some time to learn...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.I agree with this, but I think one also has to be realistic about just how much one has to learn--and unlearn.
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.This is a question of philosophy, not physics. In physics, we build models and use them to make predictions. Sometimes the predictions...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.Not if the answer is "it's not even wrong". Your analogy is too far off to even be corrected. You're better off just throwing it away...
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PeterDonis reacted to PeroK's post in the thread I I don't see how a black hole's event horizon can be crossed with Like.
What you see as a "path to learning" looks like a confusion of ideas to me. That said, you have to choose your own path. Where that...
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PeterDonis replied to the thread I Gauss' law seems to imply instantaneous electric field.Yes. The current might be constant but the charge density is changing with time, so what I said still applies. Not the way you're...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.Because you're starting from premises that have nothing to do with the black hole scenario. You need to start fresh, from premises that...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.I'll comment separately on misconceptions about the "barn and ladder" scenario, but really it's off topic for this thread and discussion...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.There is no such thing as "the" now of any observer. I.e., for a wrong reason. The barn and ladder scenario has nothing to do with the...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed.If you mean that relativity of simultaneity is involved in the "barn and ladder" scenario, yes, that's true. But relativity of...
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PeterDonis replied to the thread I I don't see how a black hole's event horizon can be crossed."Now" is not a physical thing in relativity. It's a convention. Trying to think in terms of "now" will only get you very confused...