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Is there a way to capture scenes from past for ex/ capturing someones sound which lived before long time ago.. if yes, how? and if no, why? Regards

Michael Nur
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  • No offence intended, but could you expand a bit on this question? For example, the light from far away stars is in the past for us. –  Jun 12 '15 at 20:58
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    I took a picture of my kids yesterday, does that count? – Kyle Kanos Jun 12 '15 at 20:59
  • yes, right it is past even the sound we hear is some how from close past, but what am asking is capturing something from our own past hope you got me. thanks for your attention. – Michael Nur Jun 12 '15 at 21:04
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    Do you mean, some way, other than using any form of technology, recording, filming, writing, etc. to capture our own past? If you do, that, to me only leaves memory, which is a BiologySE question, imo. –  Jun 12 '15 at 21:12
  • no it is okay to use technology – Michael Nur Jun 12 '15 at 21:14
  • So you're basically asking if we can transport either something from the past of you to the future? – Kyle Kanos Jun 12 '15 at 21:17
  • no me could be anyone and it is not transporting, cause light waves and sound waves are exist all around us – Michael Nur Jun 12 '15 at 21:19
  • no me could be anyone and it is not transporting, cause light waves and sound waves are exist all around us – Michael Nur Jun 12 '15 at 21:19
  • Related: http://physics.stackexchange.com/q/11940/2451 , http://physics.stackexchange.com/q/162011/2451 and links therein. – Qmechanic Jun 12 '15 at 21:31
  • Easy to be transported to the future. Just wait long enough. – Steeven Jun 12 '15 at 22:02
  • This question has a rethorical side. The answers help a lot. But, in general, the past is not accessible because the thermodynamic 2nd law and the uncertainty. –  Jun 12 '15 at 23:13

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Time is a continous flux that goes from the past to the future; you can't stop it, you can only accelerate or decellerate it. From relative theories and from quantum mechanics we know that, in the most of case, the max speed of informations is the speed of light. So we can see events from the past: we can observe the light of a star that, now, is died. Only in this way is possible to look at the past; at the opposite you can't see an events that are finished also in our system (if we can't see the light of the star also in our system , there is no way to take a "photo from the past")

Fabrizio
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You may be inquiring about a mechanism to separate sound vibrations which originated yesterday from sound vibrations which originated just an instant ago.

If you stood inside the Capitol dome with sensitive enough apparatus, could you hear the residual vibrations of voices which spoke yesterday or a hundred years ago?

The question is (1) whether vibrations could persist in recognizable form without being damped into quietude by friction and their surroundings or rendered unrecognizable by interference, and (2) how to identify vibrations by time of origination.

This is like the question of Julius Caesar's last breath. Enrico Fermi once asked his students how many molecules of Caesar's last breath they suck in with each inhalation. Assuming that the molecules of air which Julius Caesar expired at the moment of his death would have mixed and equilibrated throughout the Earth's entire atmosphere by now, here is one way to arrive at an answer: http://www.hk-phy.org/articles/caesar/caesar_e.html.

So, yes, remnants of the past are still here, but no it probably isn't possible to recognize them unless they are robust and persistent, or received special preservation treatment at time of origination.

Time might be thought of as the motion of matter, not as a separate medium in which matter moves. If there's no medium called time, there is nothing to recover other than the motion of matter (and of photons) as an artifact of prior states.

Ernie
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  • interesting, particularly in ergodic context. But, we can see very old images in the sky –  Jun 12 '15 at 23:00