Everything is in motion, yet nothing is really moving.

[CryptoCraig]

Of course all things, you can say, has motion or the ability to move, but only relative to another object or observer.

Lets dive into a possible future of our civilization. In this scenario imagine humans are advanced beyond belief. Part of the workforce actually commutes from Earth to asteroids we have diverted to become Earth's "natural" satellites. Within the workforce, there are a few people who travel to and from Earth and Mars, and do so either weekly or even daily making the round trip.

Given the above description of our future selves, you can safely say we have some very quick moving space craft. Somehow these fast moving spacecraft we've built go multiple times the speed of light. Or do they?

The spacecraft and it's occupants power the craft up and accelerate to 80% of the speed of light (from Earth's perspective). The ship's occupants, however, are seeing the Earth move away from them at that speed. The same thing is observed when the ship hits Mach 5 (if light was sound), or 5 times the speed of light. This works because this ship isn't really "accelerating". It's able to somehow scan the universe for an area of space that is moving in the desired direction. Then, it simulates the ship being in that area. (Just some sci-fi stuff really).

My point:

What determines which observer experiences less time due to dilation?

If the ship didn't leave from Earth, but let's say its interstellar and just appears to be moving quickly, when really, it's movement through our solar system is due to our system moving within the Milky Way. In this case, does the spaceship floating by Earth have a "slower" clock? Or does Earth?

Just another thought. With space being so vast, when you are cruising in your spaceship at 99.999% the speed of light, uh, I mean when your ship is sitting in the void of space and everything around the ship is moving at that speed.

Isn't it more than likely the Earth is moving at light speed relative to some other object in the distant universe?

I don't think light speed or speed in general can cause time dilation anymore, without some of these thoughts/questions answered.

 

[Classical Motion]

Motion IS energy. That’s what energy is. Nobody says that. All of our different energies are just types of motions, or potentials for it. Energy is motion.

Motion in this cosmos is perpetual. It’s not relevant to any observer. Mass is self powered. All mass is in perpetual motion. All fields are in perpetual motion.

This motion can not be stopped. It can only be transferred.

Perpetual motion…...No. 1 property of this cosmos.

Motion is conserved.

And can be alternated from linear to angular. Velocity into acceleration, acceleration into velocity. With just a directional change.

Classical Motion.