Difference between revisions of "Talk:1203: Time Machines"

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Source: http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html#ixzz2RMMowXrs" {{unsigned ip|128.12.95.6}}
 
Source: http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html#ixzz2RMMowXrs" {{unsigned ip|128.12.95.6}}
  
But with that above analogy, in a sound system, you have external power to amplify the signal - the energy the microphone takes out is not what gets put back out. In a wormhole, unless there is something to amplify the radiation that comes out the other end then it's a closed system (and if you do amplify it then where did THAT energy come from).
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But with that above analogy, in a sound system, you have external power to amplify the signal - the energy the microphone takes out is not what gets put back out. In a wormhole, unless there is something to amplify the radiation that comes out the other end then it's a closed system (and if you do amplify it then where did THAT energy come from). (Nigel 08:39, 24th April (UTC))

Revision as of 08:39, 24 April 2013

This one kinda went over my head; the explanation is the best I could come up with. Alpha (talk) 05:00, 24 April 2013 (UTC)

Examine the transcript and Cueball's movement in the second and third panel. The time machine in this comic is a time-reversing one, not a time jumping one. Davidy²²[talk] 05:13, 24 April 2013 (UTC)

My thoguhts: Cueball turns on the time machine, which starts up and they start going back in time, returning to the time the machine it turned on. Time is going in perfect reverse, so the machine switches off and then he is back where he started. 216.81.49.162 05:10, 24 April 2013 (UTC)


The Machine even turns back Cueballs actions, so maybe even his memory of turning it on, what might make him so puzzled - eventually - if he decides rational to try the machine (and if desicdes always rational) - he will get in a loop of turning it on - travelling back and forgetting that event - and turning it on again. - That might get Interesting 212.202.64.10 05:32, 24 April 2013 (UTC) Lupo

I don't think he looks puzzled because nothing happened, I think he's curious b/c he just came across a Time Machine. That is, the last frame of the strip takes place seconds before the first. So the "trouble" with time machines (of this variety) is that if you go back in time you can't take the present with you, and nothing changes. 76.95.49.45 06:00, 24 April 2013 (UTC)

Alternative view: Feedback. Stephen Hawking has discussed the general problem with a whole class of time machines (namely, wormwhole based time machines), where the energy from the future is added exponentially to the system due to system feedback. More or less as a microphone cannot get too close to its speaker without having that horrible sound. This would explain who the guy in the comic turns the machine off... there is a large buildup of energy feedback and this can be observed in the EEEEE...

"In the end, I think a wormhole like this one can't exist. And the reason for that is feedback. If you've ever been to a rock gig, you'll probably recognise this screeching noise. It's feedback. What causes it is simple. Sound enters the microphone. It's transmitted along the wires, made louder by the amplifier, and comes out at the speakers. But if too much of the sound from the speakers goes back into the mic it goes around and around in a loop getting louder each time. If no one stops it, feedback can destroy the sound system. The same thing will happen with a wormhole, only with radiation instead of sound. As soon as the wormhole expands, natural radiation will enter it, and end up in a loop. The feedback will become so strong it destroys the wormhole. So although tiny wormholes do exist, and it may be possible to inflate one some day, it won't last long enough to be of use as a time machine. That's the real reason no one could come back in time to my party.

Source: http://www.dailymail.co.uk/home/moslive/article-1269288/STEPHEN-HAWKING-How-build-time-machine.html#ixzz2RMMowXrs" 128.12.95.6 (talk) (please sign your comments with ~~~~)

But with that above analogy, in a sound system, you have external power to amplify the signal - the energy the microphone takes out is not what gets put back out. In a wormhole, unless there is something to amplify the radiation that comes out the other end then it's a closed system (and if you do amplify it then where did THAT energy come from). (Nigel 08:39, 24th April (UTC))