Ride Gravitational Waves to Increase Speed?

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Discussion Overview

The discussion revolves around the concept of using gravitational waves to facilitate faster space travel, particularly through the manipulation of mass and spacetime as an object approaches the speed of light. Participants explore the implications of relativistic mass, gravitational waves, and the curvature of spacetime in this context.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant proposes that accelerating an object near the speed of light increases its mass exponentially, which could warp spacetime and potentially allow for "riding" gravitational waves to achieve faster velocities.
  • Another participant challenges the assumptions, stating that the claims regarding the increase of mass and the propagation of gravitational waves are incorrect, suggesting that conclusions drawn from these premises are suspect.
  • There is a discussion about the concept of relativistic mass, with one participant noting that it has been largely discarded in favor of energy and momentum as the relevant quantities that affect spacetime curvature.
  • Participants clarify that the stress-energy tensor, which includes energy and momentum, is what actually curves spacetime, rather than mass alone.
  • Some participants express confusion regarding the definitions and implications of relativistic mass and its role in gravitational interactions.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as there are multiple competing views regarding the validity of the initial assumptions about mass, spacetime, and gravitational waves. Disagreements persist about the interpretation of relativistic mass and its relevance to the discussion.

Contextual Notes

Limitations include unresolved definitions of relativistic mass, the dependence on the understanding of gravitational waves, and the implications of the stress-energy tensor in relation to spacetime curvature. Some participants express uncertainty about their interpretations and the correctness of their statements.

wcivch
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TL;DR
Can you use conservation of momentum and gravitational waves to facilitate faster space travel?
This is my first post so I apologize if i am in error anywhere. I recently had a thought that I have had trouble confirming. Based on the following assumptions.

1.) As you accelerate an object near the speed of light it’s mass increases exponentially.
2.) Mass warps space time.
3.) Spacetime expands via gravitational waves at the speed of light.

Essentially what I was wondering is could you use an accelerator to move an object or particle (in a circle around the space craft) to approach the speed of light. The object would gain mass exponentially warping spacetime. Then stop accelerating the object and the relative mass would decrease causing spacetime to ripple outwards as it “corrects” the warping from the now gone mass. If you accelerated the craft, could you “ride” the gravitational wave to achieve much “faster” velocities?
 
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wcivch said:
Summary:: Can you use conservation of momentum and gravitational waves to facilitate faster space travel?

1.) As you accelerate an object near the speed of light it’s mass increases exponentially.
2.) Mass warps space time.
3.) Spacetime expands via gravitational waves at the speed of light.

(1) and (3) are incorrect. So any conclusions based on that are suspect.
 
(Changed thread prefix from "A" = Advanced/Graduate School level discussion to "B" = Basic level discussion.)
 
Vanadium 50 said:
(1) and (3) are incorrect. So any conclusions based on that are suspect.
Have I misunderstood relativistic mass? M= yMo. As well as the speed of gravity is the speed of light and gravitational waves propagate at that speed. Relativity showed that gravity was not instantaneous and that it’s effects were bound by the speed of light. Where am I missing something? Or maybe I’m just poorly describing?
https://ned.ipac.caltech.edu/level5/ESSAYS/Boughn/boughn.html
 
wcivch said:
1.) As you accelerate an object near the speed of light it’s mass increases exponentially.
Relativistic mass has been discarded for decades now, and even Einstein recommended against it about a century ago.

What does increase is energy and momentum

wcivch said:
2.) Mass warps space time.
The stress energy tensor curves space time, and the stress energy tensor includes energy and momentum. However, in some sense the curvature from the momentum undoes the curvature from the energy. So when both are increased you don’t get an increase in the spacetime curvature.

So this will not help surf a gravitational wave to higher speeds
 
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wcivch said:
Have I misunderstood relativistic mass?
Yes. It is not the source of gravity. The stress-energy tensor is the source of gravity. But an object's stress-energy tensor is a frame-independent object. Relativistic mass is not.

wcivch said:
the speed of gravity is the speed of light and gravitational waves propagate at that speed
This is correct, but your (3) in your OP does not say what the quote just above says and is not correct.
 
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