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If you think of it OG. To retrieve that probe it will have to be in its so called 'rest frame'.
Assuming that the cargo bay is built to the dimensions we found the probe to have before joining up with it,
becoming 'still' relative it, it will be found not to fit.
You still don't get it OG? We measure, and from there construct what is 'real'.
However, Lightarrow's example of light certainly causes a bit of an issue for this definition of rest properties=intrinsic. Light has no rest frame, yet a photon clearly has invariant mass which seems to be intrinsic. It also has spin, which certainly meets the criteria most folks would set for intrinsic (and indeed, it is technically termed an intrinsic property in relativistic QM).
From JP, a few posts ago in this busy threadQuoteHowever, Lightarrow's example of light certainly causes a bit of an issue for this definition of rest properties=intrinsic. Light has no rest frame, yet a photon clearly has invariant mass which seems to be intrinsic. It also has spin, which certainly meets the criteria most folks would set for intrinsic (and indeed, it is technically termed an intrinsic property in relativistic QM).Yes I clearly goofed up here. Clearly a photon has (at least? only?) three properties that should be regarded as intrinsic, in spite of the fact that it has no "rest frame": a zero spin, a zero "rest mass", and a "vacuum speed" of c0. But the "colour as emitted" of a photon must be seen as an intrinsic property of the emitting body rather than the photon, because it is only by translation to the rest frame of the emitting body that different observers can agree on this sort of property, and it is only in this frame that the "character" of the photon can be assessed (e.g. a sodium emission line).It seems to me (a propos of lightarrow response 87) that whether or not a particular observer finds this translation practically feasible is not particularly relevant to how the property should be regarded.
Old Guy, if you define "really" to mean in the rest frame then your logic holds. This isn't an accepted meaning of the term "really" in science, which is why you're getting push-back from others.
Here's a question for you: would you agree that the result of the measurement of the probe from the earth's frame (where the probe is moving very rapidly) is 10 meters?
Quote from: JP on 13/09/2012 21:42:43Old Guy, if you define "really" to mean in the rest frame then your logic holds. This isn't an accepted meaning of the term "really" in science, which is why you're getting push-back from others. Yes, I do. I am advocating realism here as apposed to the idealism that reality is defined by observation and measurement. The question of how best to measure something is a technical question. I think it is reasonable to be "in the rest frame" with whatever science is measuring, rather than flying by the object being measured at relativistic speeds.QuoteHere's a question for you: would you agree that the result of the measurement of the probe from the earth's frame (where the probe is moving very rapidly) is 10 meters?Yes.
old guy's original formulation was in terms of a fly-by and compare rather than an actual attempt at docking at relativistic speed.
I therefore ask OG -- is this a fair proxy for your thought experiment? Would you agree with my interpretation of the possible results of such an experiment?
Assuming that mass is a constant uniform acceleration what is then a geodesic? 'ripples'?I better put this in New Theories' huh
Ok, that's fair enough. It sounds like you don't disagree with the predictions of special relativity. You just disagree with the idea that we call our measurements "real" lengths. I guess that's fair, but it's why no one in special relativity uses the term "real." You can go into philosophy and argue about the definitions, but as far as science is concerned, which deals with measurements, we simply have to admit that we measure one length in the rest frame and another in the moving frame and leave it up to philosophers to argue over what's "real" or not.