If time slows to a near stop for objects travelling close to the speed of light, what happens to time when all momentum is at a dead stop?
The short answer is, with true zero momentum, you would cease to exist. If you had very small momentum, then time would pass very very fast for you. This is because relativistic momentum is much more complicated than just a car on a highway.
Can you be relative to nothing?
Every mass affects every other mass in the universe via gravity. There is no point of zero *inside* the universe. That would be past the margins of the expanding universe, which doesn’t have spacetime, so we can’t exist there. *There* doesn’t even exist.
At what point is a body its own body, and not part of the big thing with gravity it’s sitting on top of?
When/where do you want it to be? This is not a binary transition. It’s gradual, from the center of a black hole, out to two photons spiraling across the universe in opposite directions.
Everything is energy.
* Mass is a 4-vector, and relates directly to energy.
* Energy is a 4-vector, and relates directly to momentum.
Because of this, time is affected by both:
* More velocity = slower time, shorter length in the direction of travel
* More mass = slower time, shorter length radial to the mass.
Spacetime is a foam.
* The speed of time, like the size of space, is the size of the bubbles.
* The stretch of the foam is gravity.
* The more energy/mass on the skin of a bubble, the smaller it gets (and the more it pulls on its neighbors).
* Less energy (and mass) means bigger bubbles (ie, more time and space).
Bosons are energy carriers, and they live on a bubble.
* To move a boson, you have to input energy.
* When they have enough energy to move, they move at the speed of light.
* Photons are the most familiar bosons.
Speed of light is actually “speed of light in a perfect vacuum”.
* Put light into a ceramic crystal, and it’s slower.
* Spacetime foam is more dense, so more bubbles to transit.
To travel faster, you have to input more energy.
* More energy means you compress the foam.
* That means more bubbles to transit, which means more energy.
* As a baryonic mass approaches the speed of light, the energy inputs approach infinity.
* Infinite energy (and mass and spacetime) do not exist, so we are constrained.
Bosons and some small particles can seem to violate this on very small scales (tunnelling).
* This is because they can slide through the skin of the bubble rather than having to compress the bubble.
* You cannot do that as baryonic mass, but maybe if your pattern was translated into bosons.
* That high of an energy density would probably condense AND dispese, so you’d lose the pattern along the way.
Special relativity covers “objects at rest”:
* energy-momentum relation: E^2 = (pc)^2 + (m0c^2)^2
* energy-mass relation: E = mc^2 (p is zero, so you have E^2 = (mc^2)^2) which becomes E=mc^2
So, if you were to come to a complete rest relative to the fabric of spacetime,
* the passage of time is still affected by your own mass/energy.
* You could decreate your energy, reduce your mass, dispurse your mass, and you would expand the bubbles.
* This would cause time to pass more quickly for you, if “you” could exist that way.
At zero energy, the bubbles would be infinitely large.
* How do you pump energy out of the bubbles (vacuum fluctuations).
* Time would pass at infinite speed (same issue as photons at infinite velocity).
* Just as there is not infinite energy, there is also not infinite time velocity.
Imaginary mass/energy is described by tachyons.
* They do not travel faster than light,
* nor do they travel backwards in time.
To travel backwards in time:
* You need negative energy.
* This is also the principle behind the Alcubierre Warp Drive.
* This would cause spacetime to move around an object, instead of the object through spacetime.
* There is no known way to form negative mass/energy:
This is not the same as antimatter, which is just opposite quarks.
* Basically, you’d have to pump energy out of the bubbles.
* The excess energy generated would accumulate at the margins of the bubble, trying to get back in.
* When the bubble is allowed to collapse, it would be a giant explosion of radiation.
* If you had a way to direct this to one side, perhaps travel would be possible, leaving a radiation wake.
* Perhaps it would lead to a spike of radiation that pierced the ship, or whatever was in front of it.
That’s a theoretical exercise, which I don’t believe is likely to happen.
* We’re more likely to find a way to connect the quantum foam in different places (wormholes).
* Would a wormhole unravel spacetime, or collapse instantly?
* The margins of the universe are probably expanding at the speed of light.
* The volume grows more rapidly as time passes, even though the mass/energy is constant.
* Eventually, the universe will be so dispersed as to be useless (heat death = cold death).
* Even solid matter will disperse given enough time. Bosons trickle away, and atomic forces will decay.