Why does light even move? what force makes it move at insane speed?
In: 193
Nothing. Nothing makes light move that fast. Literally.
Light as almost 0 mass. Which means its not *slowed down* much (if any). Everything is in motion. Everything is moving. There’s no force behind this motion it’s just the state of things. Mass makes things move slower the more of it a given thing has.
Also, nothing moves. Literally.
This is part of that whole thing Einstein came up with that everyone knows of, but basically no one knows what it means. Space and time are the same thing. To move in space is to move in time, to move in time is to move in space.
Time and motion are also 100% relative. To everything. All the time.
No. Relay.
If you were moving at almost the speed of light, time would seem to stop for you, and consequently, motion would seem to stop. From your pov. From our PoV you’d basically just teleport away.
Fun fact, no pov is correct. All of them are right at all times, always. Does that make any sense? Nope! But it’s how this 8th grade shop class birdhouse of a universe is set up.
What’s this mean? It means a lot of our ideas about how things work are only true from our reference frame (science talk for PoV) on this dirt ball we call Earth. If you were moving just under the speed of light away from the center of our galaxy, and you were passed by someone moving at the same speed as you but in the opposite direction, they would appear to be moving faster than light from your reference frame, and all observations and measurements you could make would also say they were moving faster than light.
TLDR; Speed, motion, distance, and time are illusory effects created by the 3 spacial and 1 temporal dimensions of spacetime, and consequently what we know of them is only a fraction of their true nature.
If it doesn’t move that fast, it wouldn’t be called light. Light is actually part of something bigger that can move at various speeds (and can even decay very quickly). The component that move fastest is called light. You just don’t see the other components normally, because if it moves slower it has mass, and when it has mass it decay in strength, and in fact it decays so much that its range of movement is effectively less than the size of a proton.
You’ve got a lot of answers to the light-specific part of the question, but a comment on the second part of the question:
Movement doesn’t require force. Only a *change* in movement requires force.
You’re used to associating movement with force because we live an environment that always has things slowing us down. If you’re moving along the ground, you have friction. If you are moving through the air, you have air resistance. So you need a constant force pushing you forward, in order to cancel the forces slowing you down.
If you’re out in empty space and you are flying along, you don’t have or need any force to keep moving.
There are lots of “fast” things that aren’t light, e.g. solar neutrinos that have mass, but move at *nearly* (not quite) light-speed (by our reference frame). They don’t need an active or ongoing “force” to keep moving. They just do that forever until they hit something.
A light analogy that keeps my brain happy is imagining a table of billiard balls all touching one another. An impulse one side causes an almost instantaneous reaction the other – the time between the cause and effect being a function of the physical characteristics of the medium and being a constant
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