4 ms·

I’ve always wondered if gravity could be seen as like a flux, and measured by bounds vs time. So if any physicist here could shoot this down, I’d be most happy

I’ve always wondered if gravity could be seen as like a flux, and measured by bounds vs time. So if any physicist here could shoot this down, I’d be most happy: Let’s say I ran between opposite ends of a basketball court. Back and forth, back and forth... what would happen if I started increasing my speed, slowly all the way to the speed of light? So my thinking is as you become significantly faster, you become heavier, but to yourself, you don’t see any change - so it’s not me who’s getting heavier as I start to run faster and faster to the speed of light, but the enclosed box of me between opposite ends of the court - i.e gravity is the flux of a moving object bound between a distance measured over some time period? i.e some sort of integral of moving matters between a distance, with respect to time. Sorry for my incorrect science... I was just curious how relevant my thinking is

behindsight 6y ago
> but to yourself, you don’t see any change This hints to me that you might be thinking of the concept of invariant vs relativistic mass[0] > i.e some sort of integral of moving matters between a distance, with respect to time. It might be easier if you intuit it as total energy (encapsulates the relativisic aspects) - but that description you wrote seems to be another way to rephrase the curvature of space-time analogy; you could say that what you are describing is retreading how "steep" the bend is, yes? 0: https://en.wikipedia.org/wiki/Mass_in_special_relativity https://en.wikipedia.org/wiki/Mass_in_special_relativity
- alfiedotwtf 6y ago
  Yes? To be honest, I don’t know... despite 2 years of university physics, we sadly never got to the fun physics - relativity and particle physics
IX-103 6y ago
I don't think you can think of it as becoming heavier in the traditional sense, as the higher speed does not increase the force of gravity. There are several (roughly equivalent) ways to describe what happens as you approach the speed of light. One is that instead of gaining mass, you gain extra inertia, making changing the velocity require more force. This makes it appears to outside observers like your acceleration slows down. I don't particularly like this explanation as it doesn't explain why your rate of energy usage appears to go down (as that is more a function of your clock). I prefer the other explanations: Another is that your clock slows down relative to the outside world so you have less time to apply your force so you need more force to apply the same externally visible acceleration. Another is that the outside world looks shrunk in the direction of travel, so again you have less distance to a apply your force to drive the externally visible acceleration. This is effectively the same as previous since distance=time*speed.
- alfiedotwtf 6y ago
  Thanks for your explanation! Damn physics is fun since it seems intuitive and yet bizarre at the same time

behindsight 6y ago

> but to yourself, you don’t see any change This hints to me that you might be thinking of the concept of invariant vs relativistic mass[0] > i.e some sort of integral of moving matters between a distance, with respect to time. It might be easier if you intuit it as total energy (encapsulates the relativisic aspects) - but that description you wrote seems to be another way to rephrase the curvature of space-time analogy; you could say that what you are describing is retreading how "steep" the bend is, yes? 0: https://en.wikipedia.org/wiki/Mass_in_special_relativity https://en.wikipedia.org/wiki/Mass_in_special_relativity

alfiedotwtf 6y ago
Yes? To be honest, I don’t know... despite 2 years of university physics, we sadly never got to the fun physics - relativity and particle physics

IX-103 6y ago

I don't think you can think of it as becoming heavier in the traditional sense, as the higher speed does not increase the force of gravity. There are several (roughly equivalent) ways to describe what happens as you approach the speed of light. One is that instead of gaining mass, you gain extra inertia, making changing the velocity require more force. This makes it appears to outside observers like your acceleration slows down. I don't particularly like this explanation as it doesn't explain why your rate of energy usage appears to go down (as that is more a function of your clock). I prefer the other explanations: Another is that your clock slows down relative to the outside world so you have less time to apply your force so you need more force to apply the same externally visible acceleration. Another is that the outside world looks shrunk in the direction of travel, so again you have less distance to a apply your force to drive the externally visible acceleration. This is effectively the same as previous since distance=time*speed.

alfiedotwtf 6y ago
Thanks for your explanation! Damn physics is fun since it seems intuitive and yet bizarre at the same time