Re: How does time work? Pt II Special Relativity.
Posted: Mon Mar 27, 2017 1:34 pm
How can that be demonstrated if they can only be compared once, which is when they pass each other? To do a comparison, a second comparison must be taken which, if done at a distance, is completely dependent on arbitrary selection of frame. So at least one of the clocks needs to alter the frame in which it is at rest for them to be compared a second time in each other's presence.uwot wrote:Kinematic time dilation is a consequence predicted in SR, but real world kinematic time dilation is not a result of the idealised situations described in SR. Clocks really do show that they have run slower or faster, when compared to clocks they have been moving relative to.
There is no physical slowing of a clock that results from velocity since velocity is not a property of a thing, velocity is a mathematical relation with an inertial reference frame which is a mathematical thing, not a real thing I can put in a box. No clock actually changes because of a mathematical designation of how fast it is going. It can't actually have the property of velocity since that is not a measurable property of something.
Physical distance between two points J and L is accurate only if the tape measure is pulled straight from J to L and does not take a detour to K way off to the side first. Clocks work the same way, measuring the temporal distance between P and R, but the clock that takes a non-straight path from P to R, detouring to Q along the way, gives an inaccurate result. It doesn't mean the clock measured wrong any more than the tape measure stopped measuring actual meters. The measurement of temporal distance from points P to Q and from Q to R are completely accurate (not some inaccurate dilated figure), but adding them does not yield the correct measurement from P to R if the three points are not all on the same line, which they're not.
Agree, you haven't gotten into it yet, but the title suggests it is about relativity and it hinted that it would get into this sort of experiment.I will look at it again to do it justice and make sure I haven't messed up, but it is nothing to do with my blog.Noax wrote:I took a couple days to proofread and get it right, but maybe I messed up somewhere. The names and numbers are my own. I did not copy this story from anywhere.
Remember the distant object billions of light-years away? In it's frame, right now, the universe is actually about 50 billion years since the big bang, a good deal of the stars have burned out, and our Solar system is moving at say .96c and we still have a burning star, and it looks like only 13.7 billion years since the big bang from here because all the clocks and the star consumption are dilated down to .27 of the pace we would get if stationary. Einstein noted this sort of thing (that there is a place right now that is any arbitrary point in time you want), and thus it makes no sense to declare only one of them to be the actual current age of the universe. Hence he discarded the model of 3D space in which the state of things change, in favor of 4D spacetime that has no external arrow pointing into it defining the preferred location 'here' which just happens to be where we are. If there was an arbitrary place that was the 'stationary one', odds are we'd be moving at least that fast relative to it. Almost all the arbitrary places in the universe are at least that far away from us.