All Questions
Tagged with faster-than-light spacetime
52
questions
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Can we use the fabric of spacetime to go faster than the speed of light?
If the fabric of spacetime isn't bound by the limit of the speed of light (the universe is expanding faster than the speed of light), could humans somehow wrap a spaceship in a bubble of the fabric of ...
-2
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1
answer
65
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Lorentz transform causes Faster than light motion for Spacelike-separated object?
Consider a 5-meter rod which exists on the x-axis of a frame of reference:
Now consider an observer moving at a velocity $0.1c$ relative to this reference frame, from right to left. Their frame of ...
6
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1
answer
356
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Are there any Alcubierre Style metrics for sub-luminal speed warp drives?
In most literature I have found, research into the Alcubierre Metric, and Warp Drives seems to be highly focused on the plausibility of superluminal travel.
Today I was thinking to myself that maybe ...
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0
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Where can I learn more about superluminal signaling in curved spacetimes?
Typically, when discussing superluminal signaling in flat spacetime (specifically, how particles travelling faster than the speed of light can travel backwards in time in the frame of reference of a ...
17
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2
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Space falling faster than light after it falls inside the event horizon of a black hole?
Typing my question directly so people know what I am asking, afterwards providing background and context.
Q: What does it mean when space is falling, faster than light?
(I am specifically wondering ...
- 398
1
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1
answer
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Why does the Alcubierre drive need a negative energy ring specifically?
Now, maybe this is a result of my poor understanding of spacetime, but a theoretical warp bubble contracts space in front, and expands it in the back. Positive energy always contracts, so I get the ...
- 333
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2
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If spacetime can expand faster than the speed of light, then can a black hole do that too?
I have read this question:
Yes, the expansion of space itself is allowed to exceed the speed-of-light limit because the speed-of-light limit only applies to regions where special relativity – a ...
- 29k
3
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2
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How can spacetime be expanding faster than the speed of light? [duplicate]
How can spacetime be expanding faster than the speed of light when the speed of light is the speed limit of the universe?
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2
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Are a tachyonic particle a mathematical impossibility (not just physical)?
I recently learned from a helpful SE user that, in general relativity, the "law of geodesic motion" is actually a mathematical law, not a physical one. That is, a "test particle" (...
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1
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If you could zero out your momentum, could you travel faster than the speed of light [closed]
I figure I'm going to get ridiculed for this question, and maybe deservedly so. The sensor images and eyewitness accounts from the Naval Aviators released last year of unexplained aerial phenomena ...
- 207
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6
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Why does FTL imply that BACKWARDS time travel is possible? - Very Detailed! [closed]
I know this question has been asked before and I have read and understand the answers however imo none of them still imply that backward time travel is possible.
I understand moving forward in time ...
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2
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0
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68
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What would happen if universe wouldn’t accelerate faster than speed of light? [closed]
Its quite stunning to assume that not only space-time is expanding but also the rate of expansion is greather that speed of light.
But after the initial surprise, I ve been wondering if that fenomena ...
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2
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1
answer
59
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What is observed by Astronauts traveling from M at just under $c$, but proper distance increases at greater than $c$ due to spacetime expansion?
A rocket is traveling at a reasonable speed directly away from planet M at a large distance D. M is shaped like a coin and to the astronaut looking through a telescope directly out the back of the ...
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4
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129
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Observed Behavior of Light When Relative Motion $> c$
I am trying to wrap my head around some of the implications of relativity. Hopefully somebody can help enlighten me with a specific example I am wondering about:
We have 2 objects, A and B, that are ...
- 113
2
votes
1
answer
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Age versus size of the universe [duplicate]
QUESTION CONTEXT:
The universe is roughly 14B years while its diameter 93B light years, making radius 46.5B ly. If I understand correctly if we froze everything, go on the one side, then go to the ...
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