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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 3:47 am
(This post was last modified: October 20, 2015 at 3:57 am by houseofcantor.
Edit Reason: adding stuff
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There's no actuality for such speculation "beyond c," that's part of the problem. But to collide with something "natural" requires "natural" speeds. Hypothetical tachyons are just that, hypothetical. What I think the eggheads do is use models involving a bunch of advanced math (that stuff with the squiggly lines and Greek letters) and then translate those models into common language - usually incompletely. But no, I don't know any article off the top of my dome which outlines these speculations. I'm not an egghead, I only play one on the interwebs. 
EDIT - I did just google-fu this brief essay on the problems involved here...
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 4:09 am
(October 20, 2015 at 1:10 am)Alex K Wrote: We're talking about ordinary movement through space, no wormholes or exotic warp drives as poroposed by Alcubierre.
My man made a good point the other day. Say you had a wormhole at the bottom of a gravity well and had it re-appearing at the top of the same gravity well, then you passed some water through it that moved a turbine, you would have a perpetual motion machine which is not possible.
So either you need energy in order to sustain the wormhole, or there are some other constraints like not being able to exit a wormhole at a higher point in space-time. If the latter is true then even if you can create a wormhole, you would have long journey back home again. It would be only be useful for non-returnable space probes.
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 4:38 am
Rob, buy Mermin's book " It's about time". Or ask me here and I'll answer 
The fool hath said in his heart, There is a God. They are corrupt, they have done abominable works, there is none that doeth good.
Psalm 14, KJV revised edition
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 4:45 am
(October 20, 2015 at 4:09 am)I_am_not_mafia Wrote: (October 20, 2015 at 1:10 am)Alex K Wrote: We're talking about ordinary movement through space, no wormholes or exotic warp drives as poroposed by Alcubierre.
My man made a good point the other day. Say you had a wormhole at the bottom of a gravity well and had it re-appearing at the top of the same gravity well, then you passed some water through it that moved a turbine, you would have a perpetual motion machine which is not possible.
So either you need energy in order to sustain the wormhole, or there are some other constraints like not being able to exit a wormhole at a higher point in space-time. If the latter is true then even if you can create a wormhole, you would have long journey back home again. It would be only be useful for non-returnable space probes.
Or maybe you simply need energy to cross it in one direction because there is a gravity gradient along the wormhole? I actually don't know...
The fool hath said in his heart, There is a God. They are corrupt, they have done abominable works, there is none that doeth good.
Psalm 14, KJV revised edition
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 4:54 am
So.... moving at warp 1 indefinitely, huh?
Well.... it would take a hell of a long time just to go from one end of our galaxy to the other.... Only about 100 thousand Earth years.
So I anticipate a boring trip.
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 5:04 am
I found a couple more thingies:
This one and that one.
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 5:09 am
(This post was last modified: October 20, 2015 at 5:19 am by Alex K.)
Concerning the Alcubierre warp bubble, I am still not at all convinced that it is in principle possible to use it to actually reach a destination with speed greater than light without invoking time travel paradoxes. And of course, matter with negative energy of that kind does not exist as far as we know.
The fool hath said in his heart, There is a God. They are corrupt, they have done abominable works, there is none that doeth good.
Psalm 14, KJV revised edition
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 5:20 am
(This post was last modified: October 20, 2015 at 5:23 am by houseofcantor.
Edit Reason: added more stuff
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(October 20, 2015 at 5:09 am)Alex K Wrote: Concerning the Alcubierre warp bubble, I am still not at all convinced that it is in principle possible to use to actually reach a destination with speed greater than light without invoking time travel paradoxes. And of course, matter with negative energy of that kind does not exist as far as we know.
I get to wondering if there's sort of a causality sphere that provides a lower bound limit for ftl travel. But I don't wonder too much 'cause then the stupid brain goes  
Also this, which I found interesting and posted at our alt hangout: http://www.thethinkingatheist.com/forum/...rferometer - indicating that serious peeps are taking the idea seriously.
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 6:52 am
Thanks guys!
Once the science gets past a certain point, my brain starts screaming "No! No, no, no!"
I have to learn to drop my preconceptions, just like we constantly ask of others. It takes practice, I suppose.
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RE: Travelling at the speed of light?[Question]
October 20, 2015 at 6:59 am
(October 20, 2015 at 6:52 am)robvalue Wrote: Thanks guys!
Once the science gets past a certain point, my brain starts screaming "No! No, no, no!"
I have to learn to drop my preconceptions, just like we constantly ask of others. It takes practice, I suppose.
Some preconceptions keep one out of the love-me jacket.
Guy I stole my name from, Georg Cantor, lost his nut trying to solve his Continuum Hypothesis. Kurt Godel also looked into it - with the same result. 
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