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Monster gravitational waves spotted for first time

nature.com

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Re: Monster gravitational waves spotted for first time

#11

Post by amelius »

sidcool wrote: post #4
anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

Theoretically it's impossible to travel through space at or more than speed of light. But space itself can move faster than light speed, and a warp drive would help something similar that you mentioned. That is possible theoretically. But the amount of energy or mass it needs is very high and no current technology (or in foreseeable future) can achieve it. So FTL remains a dream. My hunch based on nothing is that we…

How would someone _inside_ space make use of FTL movement of space itself?

Re: Monster gravitational waves spotted for first time

#12

Post by anonym29 »

actionfromafar wrote: post #9
SketchySeaBeast wrote: post #6

Earlier quoted context omitted.

> My hunch based on nothing is that we will achieve FTL no earlier than 2250. I see you too have been forced to give PMs estimates when you don't understand the problem.

And without a later bound, so a very reasonable estimation too.

"Did I say 2250? Sorry, I meant 22,500. Yeah, you know, with all the extra time needed to compile and everything..."

Re: Monster gravitational waves spotted for first time

#13

Post by time0ut »

SketchySeaBeast wrote: post #6
sidcool wrote: post #4

Earlier quoted context omitted.

Theoretically it's impossible to travel through space at or more than speed of light. But space itself can move faster than light speed, and a warp drive would help something similar that you mentioned. That is possible theoretically. But the amount of energy or mass it needs is very high and no current technology (or in foreseeable future) can achieve it. So FTL remains a dream. My hunch based on nothing is that we…

> My hunch based on nothing is that we will achieve FTL no earlier than 2250. I see you too have been forced to give PMs estimates when you don't understand the problem.

Is this before or after the estimate is rejected and arbitrarily cut in half?

Re: Monster gravitational waves spotted for first time

#14

Post by tnowacki »

anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

PBS Spacetime did an episode on this just recently!

https://www.youtube.com/watch?v=QMFLcmsjOBg

In the video, they mention that the models we have for FTL (by bending spacetime) wouldn't generate ripples in this way. We could however detect ripples from a really massive ship accelerating really really quickly.

Re: Monster gravitational waves spotted for first time

#15

Post by anonym29 »

tnowacki wrote: post #14
anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

PBS Spacetime did an episode on this just recently! https://www.youtube.com/watch?v=QMFLcmsjOBg In the video, they mention that the models we have for FTL (by bending spacetime) wouldn't generate ripples in this way. We could however detect ripples from a really massive ship accelerating really really quickly.

Thank you for sharing this :D

Re: Monster gravitational waves spotted for first time

#16

Post by psychphysic »

anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

The energies involved are stupendous.

It would be like being hit by a tsunami and wondering if a cruise ship caused it.

But on a galactic scale.

Re: Monster gravitational waves spotted for first time

#17

Post by mjburgess »

sidcool wrote: post #4
anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

Theoretically it's impossible to travel through space at or more than speed of light. But space itself can move faster than light speed, and a warp drive would help something similar that you mentioned. That is possible theoretically. But the amount of energy or mass it needs is very high and no current technology (or in foreseeable future) can achieve it. So FTL remains a dream. My hunch based on nothing is that we…

'space' isnt a substance that can move at any speed.

What's meant by the claim that 'space moves faster than light' is that extremely distant objects are moving away from each other, relative to each other, 'faster than light' -- which is permitted, so long as that distance can never be bridged by light.

The claim amounts to, in other words, that the universe is so large that we can compare objects at distances greater than those light could travel between them, and if we do that, they travel faster than light.

This is an "illusion in measurement" more than anything else. Nothing is travelling faster than light.

Re: Monster gravitational waves spotted for first time

#19

Post by DexesTTP »

amelius wrote: post #11
sidcool wrote: post #4

Earlier quoted context omitted.

Theoretically it's impossible to travel through space at or more than speed of light. But space itself can move faster than light speed, and a warp drive would help something similar that you mentioned. That is possible theoretically. But the amount of energy or mass it needs is very high and no current technology (or in foreseeable future) can achieve it. So FTL remains a dream. My hunch based on nothing is that we…

How would someone _inside_ space make use of FTL movement of space itself?

To simplify, the same way that a surfer on the sea can use the movement of the sea itself (waves) to surf!

An Alcubierre drive (they're theoretical) would basically constantly compress the time curve of spacetime in front of the craft, allowing the craft to "ride" this compression as it moves forward, which means that the local speed of light of the craft is faster than the speed of light of an external observer. Note that the main issue we have is to find something that can compress space, and then to have it have enough energy for it not to be trivial (because 110% of the speed of light, while technically FTL speed, is still very slow for interstellar travel). And of course, while the existence of something that does this spacetime curve compression fits the math we have, we've yet to find a material or technique that actually does so.

Re: Monster gravitational waves spotted for first time

#20

Post by edgyquant »

psychphysic wrote: post #16
anonym29 wrote: post #3

EDIT as a commenter below has kindly pointed out, our current models indicate that the answer to this question is "no", per https://www.youtube.com/watch?v=QMFLcmsjOBg ------ This is all firmly outside my technical discipline, but aren't there some theories that faster-than-light travel might be achieved by bending spacetime around a spacecraft, as opposed to trying to propel the spacecraft through space? I really wa…

The energies involved are stupendous. It would be like being hit by a tsunami and wondering if a cruise ship caused it. But on a galactic scale.

Are not the energies required for a theoretical warp drive also stupendous?
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