/sci/ - Science & Math

>>15027439
Hey you reached an important point in the life of a simian. You just realized that when analyzing aspects of the universe beyond what was necessary for your immediate survival in the Savannah, sometimes the things the universe does are not "intuitive". That's because your monkey intuition is well trained for detecting tigers in a shaking bush by the sound of their roaring. It's a bit ill suited for analyzing how things behave at 0.999c speed.
In other words. Yes, it is not intuitive. And that's a good thing

>>15027439
Time is the rate at which reality moves. If you set time to zero then nothing would move. If you increased time to twice its current rate then everything would move twice as fast. It's the measure of the progression of reality is another way to put it. Gravity and speed affect how fast time moves, which is really just affecting how fast all the particles in that region of space are moving. So different parts of the universe experience time differently and if you could see it all at once you'd see particles in one region moving around faster than particles in another. So their location in space affects the rate of time they experience. As far as I'm aware the minimum is zero, where time is not moving, so none of the particles in that region are moving. And that's also why I don't think it's possible to go backwards in time, because particles can't go into a kind of negative time where they start to rewind backwards along the path they've already taken which is what would need to happen if they were going backwards in time

>>15027439
It's very intuitive if you look at it right; you're just thinking one degree too low. Consider this:
>What are the implications of gravity dilation?
>It's not intuitive at all. You are telling me I can unironically reduce force by moving up instead of sideways? What even is the z axis? Apparently it's similar to (x,y)? That's not intuitive either. Walking and jumping are two sides of the same coin?

You just need to go from three vectors to four, plus a little flexibility. Instead of thinking of time as always moving in the same domain and speed, and space being three directions you can choose to move in independently, think of speed-of-light-ness as the thing you always move at the same speed in, only it's always a sum of your speed through space and through time. You don't get to choose to go anything but c, but you do get to choose how to split it between the four directions. Want time to go faster for you than other people? Just put more of your c into time and less into the space directions. Want it to go much slower? Just put waaaay more into space than them.

Keep in mind that the reason you struggle with imagining time dilation is because, never mind the ballpark, you've never gotten into the same continental US as experimenting with it. Ever been on a transcontinental flight? You went pretty fast, yes? Completing a month long land journey in a few hours? Not even close. Light circles the entire earth in a second. Seven times. You struggle with intuiting the sun because you've never left a sort of plato's cave where a man chained to Prevent any movement bigger than twitching his nose from birth is trying to intuit a cartwheel. It's not a strange body motion, he just only has an abstract frame of reference. If you ever get to actually move fast, to put anything beneath 99.9% of your c into motion through space, time dilation will feel just like your first time jumping off a high dive or riding a roller coaster; very new, but very natural.

>>15027564
>If you set time to zero then nothing would move. If you increased time to twice its current rate then everything would move twice as fast
...I should add to that, that if you were in that region where time was slowed down or sped up you would still experience time as normal, because everything around you is moving relative to that speed to including all the biology of your body and brain which is perceiving the progression of time. I was talking more about if your were somehow outside of that region looking at it and then adjusting the rate of time there but without affecting your current local rate of time, then you would see that distant region speed up

dilate tranner

>>15027439
More shit happening at once lags the simulation.

>>15027439
>What are the implications
the implication of space-time is time mirrors and sending messages through time.

https://youtu.be/Qd77OXWC1eg

>>15027439
>not intuitive
It is intuitive. Everyone knows what velocity is; it's speed associated with a direction. In relativity, we call "velocity" the 3-velocity to differentiate motion through 3D space from motion through 4D spacetime. 4D motion is quantified as the 4-velocity: a vector with four components instead of three. It is some weird property of the universe (Lorentz invariance) that the 4-velocity of any physical object in spacetime is normalized so that its square is always (ALWAYS!) equal to the speed of light squared. In one's own reference frame, the frame in which one is still or motionless, one observes the 3-velocity to be zero and all of one's normalized 4-velocity has to get made up by the 1-velocity. However, relative (as in RELATIVITY) to another observer in a frame moving with respect to one's own frame, the 3-velocity through space is non-zero and the 1-velocity through time has to decrease to maintain the overall normalization of the 4-velocity. This slowing down of the 1-velocity is called "time dilation." This is weird because one's "proper time" (the time on a stopwatch in the frame where one's 3-velocity is zero) always goes at a constant rate. Due to the effect I mentioned, which is called time dilation, the passage of time measured by two stopwatches moving with respect to each other will usually not agree for relativistic 3-velocities. Since the speed of light is so high and the square of the 4-velocity is ALWAYS equal to the speed of light squared (for some reason), we don't notice time dilation between frames which move non-relativistically with respect to one another.

As a counterexample, it is said that time will stop when one's 3-velocity reaches the speed of light, or that clocks don't tick in a frame comoving with a photon, because the 3-velocity squared is already equal to the speed of light squared. There's no normalized, Lorentz invariant 4-velocity left over to have some 1-velocity, which is the rate of time passing.

>>15027439
>not intuitive
It is intuitive. Everyone knows what velocity is; it's speed associated with a direction. In relativity, we call "velocity" the 3-velocity to differentiate motion through 3D space from motion through 4D spacetime. 4D motion is quantified as the 4-velocity: a vector with four components instead of three. It is some weird property of the universe (Lorentz invariance) that the 4-velocity of any physical object in spacetime is normalized so that its square is always (ALWAYS!) equal to the speed of light squared. In one's own reference frame, the frame in which one is still or motionless, one observes one's 3-velocity to be zero and all of one's normalized 4-velocity has to get made up by the 1-velocity, which is the rate of time passing. However, relative (as in RELATIVITY) to another observer in a frame moving with respect to one's own frame, one's 3-velocity through space is non-zero and one's 1-velocity through time has to decrease to maintain the overall normalization of the 4-velocity. This slowing down of the 1-velocity is called "time dilation." This is weird because one's "proper time" (the time on a stopwatch in the frame where one's 3-velocity is zero) always goes at a constant rate. Due to the effect I mentioned, which is called time dilation, the passage of time measured by two stopwatches moving with respect to each other will usually not agree for relativistic 3-velocities. Since the speed of light is so high and the square of the 4-velocity is always equal to the speed of light squared (for some reason), we don't notice time dilation between frames which move non-relativistically with respect to one another.

As a counterexample, it is said that time stops as one's 3-velocity approaches the speed of light, or that clocks don't tick in a frame comoving with a photon, because the 3-velocity squared is already equal to the speed of light squared. There's no normalized, Lorentz invariant 4-velocity left over to have some 1-velocity.