Matter always moves through time at the speed of light. Everything experiences their personal time the same way, regardless of gravity or acceleration.
Gravity and acceleration change the relative time between different objects that are experiencing different gravity or acceleration from the observer.
Actually, to answer your question as written… gravity does not bend time. Mass bends spacetime. Also, the acceleration of mass bends spacetime. Gravity is the result of mass moving through bent spacetime. What you feel as gravity is actually the force of the ground stopping you from falling further into the ‘gravity well’ of the planet. It’s the same as the centripetal force of a ball on a string spinning over your head.
This kind of makes sense, i guess. We don't feel it much because a) earth is smoll and b) we mostly stay on its surface and keep the distance. Is that about right?
When we’re on the surface of the earth we do feel the effect of gravity, because the surface is preventing us from moving on a natural geodesic (which would be a free-fall/orbit).
I'm not an expert, but from my understanding it's kind of something like this:
So a geodesic is a line of shortest length between two points on a curved surface, like two points on a ball, the geodesic would be the shortest line that connects the two.
If you look at flight paths compared to a flat representation of Earth, you'll see that aircraft seem to follow a very strange arc, that's because they're actually flying the geodesic of their route, which looks funny when presented flat.
If you imagine Earth as the aircraft and spacetime as the globe, that's essentially what is meant. However do keep in mind that aircraft follow a two-dimensional geodesic, whereas we would follow a three-dimensional one due to spacetime being four-dimensional; due to how reductions work. (3D object casts 2D shadow, 4D object casts 3D shadow).
My knowledge is rather vague past this point, but essentially orbits are geodesics against 4D spacetime, and gravity affects that temporal component.
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How does gravity bend time and how come we don't feel it or realize it? | Spyke
Matter always moves through time at the speed of light. Everything experiences their personal time the same way, regardless of gravity or acceleration.
Gravity and acceleration change the relative time between different objects that are experiencing different gravity or acceleration from the observer.
Actually, to answer your question as written… gravity does not bend time. Mass bends spacetime. Also, the acceleration of mass bends spacetime. Gravity is the result of mass moving through bent spacetime. What you feel as gravity is actually the force of the ground stopping you from falling further into the ‘gravity well’ of the planet. It’s the same as the centripetal force of a ball on a string spinning over your head.
Here, smoke this. Time dilation gets funky.
You feel it by being stuck to the ground.
Gravitational time dilation is incredibly weak on Earth, since Earth is not very massive on cosmological scales.
Yeah even if it were stronger we probably wouldn’t be able to notice anything on the surface
We do actually, just at a very small scale compared to what you may see around black holes.
Satellites in LTO need their clocks adjusted by a few dozen picoseconds I believe. Very cool.
We naturally move through spacetime on geodesics, which could be defined as “the trajectory along which you don’t feel the effects of gravity”.
This kind of makes sense, i guess. We don't feel it much because a) earth is smoll and b) we mostly stay on its surface and keep the distance. Is that about right?
When we’re on the surface of the earth we do feel the effect of gravity, because the surface is preventing us from moving on a natural geodesic (which would be a free-fall/orbit).
Could you elaborate?
I'm not an expert, but from my understanding it's kind of something like this:
So a geodesic is a line of shortest length between two points on a curved surface, like two points on a ball, the geodesic would be the shortest line that connects the two.
If you look at flight paths compared to a flat representation of Earth, you'll see that aircraft seem to follow a very strange arc, that's because they're actually flying the geodesic of their route, which looks funny when presented flat.
If you imagine Earth as the aircraft and spacetime as the globe, that's essentially what is meant. However do keep in mind that aircraft follow a two-dimensional geodesic, whereas we would follow a three-dimensional one due to spacetime being four-dimensional; due to how reductions work. (3D object casts 2D shadow, 4D object casts 3D shadow).
My knowledge is rather vague past this point, but essentially orbits are geodesics against 4D spacetime, and gravity affects that temporal component.