Why does light have a speed limit?

Who's to say the speed of light is the limit? What if it 'theoretically' could go faster, but would require some form of exotic matter, making the natural speed of light the effective limit, yet not the theoretical 'maximum speed of the universe'

Because you can't simulate infinite speed

Hey, if light passes through a medium and back into a vacuum, does it speed back up?

If you are caught speeding you might get a ticket.

Anthropic principle.

Any observer must live in a universe where observers are permitted to exist.

Such a universe must have a causal horizon, which entails some limit on the speed at which particles can move.

It's really not that hard to grasp.

The speed limit "c" is the speed of causality itself, so this exotic matter would have to bend space to allow for causality to hasten. In fact, regular matter does that via gravity. But yes, light travels at the de facto speed limit of the universe, the speed at which any one thing can cause any other thing, so speeding light up further would involve screwing with spacetime, not screwing with light.

depends, is it a hoover or a dyson?

The light's actual speed doesn't change; its path is just made bumpy since it's also traversing electron excitations in the material it's traveling through. Same phenomenon that causes color. It's the same speed in or out of the medium, but a vacuum just allows it to move straight instead of in a meandering path through a bunch of particles.

>path is just made bumpy
It's more complicated than that
youtu.be/CiHN0ZWE5bk?t=3m

It's actually not about the speed of light, it's the speed of causality . Light moves at the maximum speed of anything.

>Such a universe must have a causal horizon
why?

Anthropic principle completely fails to answer the question anyway.
Question is "why x?"
Anthropic principle says "observers exist, therefore x"
But observers existing aren't the reason for x, x just has to be true to permit observers.
Confuses logical relationship with causal explanation.

>Why does light have a speed limit?
because space and time are not two different things, they are one thing, space-time. One of the properties of space-time is that in order to accelerate mass to the speed of light you need an infinite amount of energy.

General relativity doesn't explain "why", as with most scientific models, the equations perfectly describe the behavior of a system, nothing more.

Spacetime is a 4D thing. How big are space and time relative to each other though? You convert between space and time with a velocity which could be anything but happens to be 3e8m/s. Fundamentally it's not a speed limit, it's the scale factor of space relative to time. So in 1 second of spacetime there's 3e8m.
It becomes a speed limit for things moving through spacetime. Anything that moves through spacetime unhindered (eg. light) will go that distance in that time just because that's how much each of space and time there are to go through. If it's hindered it'll go slower, it can't go faster than being unhindered.

Kek
If light maintains the same velocity, does it just not impose any force on the mediums it passes through? If so, how so? I'd imagine there would be some sort of photon drive that just cycles light through a medium at net power gain if light applied a force but never slowed down.

Light goes at different speeds in different mediums. Sr only holds in the vacuum of space.

>Why would it not have a speed limit?

Because it's massless, intuitively it should be able to travel at any arbitrary speed.

Photons always travel at c. The reason "light" slows down in a medium is because the photons are continually hitting particles of matter, being absorbed, and being re-emitted. It is the wave of light that slows, not the particles that make up the light.

>does it just not impose any force on the mediums it passes through?
en.wikipedia.org/wiki/Radiation_pressure

Could you theoretically power or propel something by just using light in a confined chamber, then? Where it hits an opaque or reflective medium, imparts radiation pressure, enters a vacuum, returns to c, and hits a medium again? Does light lose "energy" in this process or would it just be a reactionless drive?

Lunch time doubly so.

Ask differently because how do you answer "WHY" does light have a speed limit ?
How does one answer this within u'r boundary of knowledge, vocabulary even.

Nothing would happen because it would bounce around hitting all points, basically cancelling whatever thrust it generates.

If there were a method to bend the light in a manner that repeatedly only impacts a point, would it work?

For example, if there were a massive object behind a reflective material, and light were emitted away from the material, could the light lens backward onto the reflective material, bounce, and be drawn back?

Or would something massive enough to bend light that strongly automatically achieve black hole status?

Look, imagine light as bouncing balls transmiting momentum.

You can accelerate an object by illuminating one of its faces. Mirrors are objects too, so they can be accelerated in the same way.

If the object and the mirror are attached, at best you can make a light sail, albeit a very ineficient one. At worst you would be cancelling one force with another.

In any case you are better of with the source of light being outside the vessel, and not attached to it. Perhaps a giant laser, or the sun itself.

Space is in units of m^3, and speed is in units of m/s. How does a factor of x*m/s convert between the 2? Pls respond.

OP's question is about speed, that's why the answer is in m/s.
Relativistic length contraction is only in the dimension of travel, nothing happens in the other 2 space dimensions, so it's completely appropriate to consider only single spatial dimension and time.
Volumes of space are m^3 but the question isn't about them.

Perhaps some extrapolation is in order. Allow me to explain the reasoning with some simple maths.

E=MC^2

E: Energy
M: Mass
C: The speed of Causality, and also light speed in a vacuum. The speed of light has nothing to do with light itself. Light and all electromagnetic waves must always travel at C, or the universe wouldn't exist, as explained below.

E=MC^2 can be rearranged (and in fact was originally written) as M=E/C^2.

C, the speed limit of causality, must have a limit, or there is no universe for a limit to exist in. Why? Because if C is infinite, then it takes infinite energy to create mass, and a universe in which C is infinite would be an infinitesimal point of infinity, unable to contain anything except for electromagnetic waves that are all infinitely and instantaneously interacting with each other over any distance. "Distance" as a concept would not even exist, along with matter. So, to put it in layman' terms; No speed limit, no universe with people, stars or anything else in it.

space police

FINALLY SOMEONE!!!!!!

yeah but illusions have a speed limit and therefore time does by extension

Oh fuck off. He didn't actually explain it like the guy above you did.

But now why does causality have a speed limit?