Why gravity slows down the time instead of speeding it up?


In Interstellar when they were on the water planet, every minute they spent there, several days passed on Earth. From outside observer’s point of view from Earth, everything happening on the water planet was in slow motion. Why isn’t it the other way around?

In: 67

According to Einstein’s theory of general relativity, big objects with lots of gravity bend the fabric of time and space, like bowling balls on a trampoline. The closer you get to these objects, the stronger the pull of gravity and the slower time moves.

The stronger the gravity, the more spacetime curves, and the slower time itself proceeds. Time itself is slowing down and speeding up because of the relativistic way in which mass warps space and time. Earth’s mass warps space and time so that time actually runs slower the closer you are to earth’s surface.

If a body of mass is not moving, electrons circle the nucleus of an atom in a perfect circle. If you are moving, that perfect circle becomes an oval— which means it takes longer for it to orbit the nucleus.

So if you start moving REALLY fast, close to light speed, that oval becomes EXTREMELY elongated and takes much longer to orbit the nucleus. At light speed the electron could never “catch up” to the nucleus, so it could never orbit.

Electrons are pretty much how every signal is generated within the human body. So essentially you could never age at light speed. So the closer you get to light speed, the slower you age.

The question of why on the fundamental level will have the answer because that is how the universe works.

Asking why is not what scientists do. Science describes how the universe works and what is the result of that in the universe.

The answer of why gravity work that way might be that is is the only way it could work is it might be that we just by changes live i a universe that work like that, As long as we are limited to inside out universe we will always reach the point that is how the universe works.

Even if we could get outside out of the universe the question just moves the problem to that level.

Hang on. This may get a bit weird.

Time can’t speed up more due to relativity. There’s a maximum speed in space (the speed of light), but the part where it gets really weird is that everything travels through spacetime at the same constant speed. This means you and anything not moving with respect to you is travelling through time as fast as you can go because all of your spacetime “speed” is in the time direction with none in the space directions.

As soon as things start to move or spacetime gets warped to bend paths in space (which is what gravity is) time has to slow down to allow the motion in space. The more motion there is in space, the more time slows down from the perspective of both moving things. Eventually we’d get to things going at the speed of light and they experience zero time since all their speed is in space and none is in time. That’s why photons can carry information. They don’t experience time and therefore can’t change on their way from point A to point B.

I’ll freely admit I’m not an expert, so I’m not certain if funky things like negative mass can bend spacetime to increase time flow. My understanding is that that’s impossible, but I’d be happy to hear different in a reply comment.

Stretch a sheet of rubber and put a giant, heavy object in the middle to stretch the rubber down. Measure the length of the rubber in the middle and the length on the edge. The path through the middle is longer. Now imagine a marble or some other object traveling across the rubber at a specific speed that cannot change. The marble going through the stretched region will take longer to reach the opposite side of the sheet than a marble traveling on the unstretched region.

Space-time is the rubber, and causality is the marble.