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What's being referred to here is roughly the question that Einstein called the "problem of the now". That is, our experience suggests a tensed, flowing time, and the phrase is only "absurd" insofar that it seems to clash with our experience. The underlying problem is to answer why or how it is that we seem to perceive time as flowing, and the phrase is most ...


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If time was reversed we would remember only things we hadn't done yet and nothing that had happened. The laws of physics work equally well forwards or backwards, yet our everyday experiences of cause preceding effect, not the other way around makes this seem counter-intuitive. Just imagine some kids playing cricket in a universe where time is reversed. In a ...


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In this case one could argue that 'remembering the past' would be a methaphorical expression to describe being able to predict the future. Experimental evidence says that people that have declared being able to predict the future are either scammers, delusional, self-fulfilled prophecies or just extremely intuitive. As far as I can tell, there hasn't been ...


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To understand my answer, you have to imagine space as a 2-D plane and time as a vector perpendicular to it. "Normal" time is defined as a vector pointing to the "right." If time is now instantaneously reversed (vector now pointing to the left), nothing would change (laws of physics, etc.), because we could just as easily define "normal" time as pointing to ...


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Is time reversible? Look at the stroboscopic photograph. Is the ball "falling up" or falling down? The answer is surely we don't know! A motion picture of this sort of sequence of the event could be run backward & would inevitably be impossible for the viewer to detect any violation of Newton's laws. A time-reversal changes both $t,v \to -t,-v$ ...


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To expand a bit on Ian's answer, let's consider the case of a ball that has dropped from a given height and has bounced repeatedly against the ground, losing energy through partially inelastic collision with the ground until all its energy is dissipated as heat. Now if at this point time was reversed, what we might expect to see is that the flow of entropy ...


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Good question. Let's first consider the ball falling immediately before it hits the table. Neglect friction with the air for simplicity. The ball has a velocity in the downward direction. If we reverse time, the ball is in the same position right above the table, but now it has an upward velocity. A ball with an upward velocity will rise with a negative ...


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I once read of a science fiction scenario where on a planet the distance from a specific center was time. Life in that format progressed in height from the center, grew contours of certain height and became flat at death. The consciousness of those entities had time defined by their changes but humans just saw a completed contoured landscape unchanging in ...



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