Why can't anything go faster than the speed of light?

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This is something I never understood. If light has a finite speed, and what we see is only light reflecting off of our eyes, wouldn't an object going faster than light only appear to not be moving any faster? It should still physically be accelerating, just invisibly. Visible light is nothing more than energy that is exerted by or reflected against matter. Why would it have the ability to constrain the speed of that matter beyond a visible limit?

Strictly speaking, the rule is that you cannot accelerate an object to the speed of light by the application of force to the object.

As seen by an observer, an object could go faster than light if it was due to the expansion of space between the object and the observer.

But what proves that rule, exactly?

The curve of how much energy it takes to accelerate a mass goes way, way up the closer you get to the speed of light; to actually *get* to c you'd need all the energy in the universe.

Brief explanation & equation here:
http://physics.stackexchange.com/questi ... d-of-light

If it weren't for relativity, we could accelerate particles to the speed of light in a relatively small distance.

Follow up question for the relativity experts:

Is a photon that has traveled for billions of years of external observer time still in the moment it was created in its own time frame?

Relativistic mass increases with velocity. An object travelling at the speed of light, will have an infinite mass -- and thus you would need infinite power to move it. Light particles are too small to have a mass, and thus, they can travel at their designated speed.

I think you misunderstood the term, although it is lightly confusing.

light is not the limiting factor, the "speed of light" isn't enforced by light itself but by the natural laws of energy conservation combining with time/mass/distance dilation.

There is a limit to how fast anything can move in the universe, and light happens to travel at that "speed limit", so we call it the speed of light (interestingly, you *can* move faster than light, since light slows down if it is in a medium, like water, so it is possible to go faster than light in that situation, as long as you don't go faster than light would go in a vacuum).

as a side note: if something moved away from you faster than light, you would never see it and if it came towards you faster than light, you would not see it untill it has passed you.

You (the OP) seem to think that light itself is the traffic cop that slows down matter.

It is not. Its that matter cant go as fast as light. Both matter and light have the same upper speed limit. But matter cant even go as fast as that speed limit. But light is free of certain constraints that matter has, and does reach the speed limit. So that upper speed limit is referred to as "the speed of light" out of convenient convention.

Didn't matter from the big bang supposedly get thrown light years in a matter of seconds? I didn't take astrophysics but that is the version of events I heard.

Space can expand faster than the speed of light, and matter can be carried along for the ride without violating Einstein. The Universe is 14 billion years old, but its wider in radius than 14 billion light years.

Correct. The space between the elementary particles expanded at incredible speeds.

The reason it doesn't violate Relativity is that it is not due to the use of force to accelerate a particle.

The speed limit is for moving "inside" space (let's call it 'aether', for convenience), the 'aether' can move as fast as it wants with no limit whatsoever.

consider, if you will, space to be cupcake dough, and matter (stars, planets, what have you) to be the raisins on top.
The raisins have a finite speed at which they can move around in/on the dough (zero), but the dough doesn't have that constraint.
When baking, the dough expands, and the raisins end up further away from each other than they were before baking, yet they didn't move an inch themselves.
This is, roughly, what happened shortly after the big bang (or as close as i can get without getting too technical):
The aether expanded, and the matter went with it, while moving around a bit at their own top speed (the speed of light). even the particles that tried to stay close together couldn't, since they were pushed away faster than they could run back (try running on a sail that's being pulled backwards by a car, you'll end up moving backwards too, albeit a tad slower)

+1, From someone with a hobby of studying Victorian and Elizabethan science history, especially regarding the social shifts & memes prompted by the many new discoveries that involved, "action from a distance" like radioactivity.

I prefer the"flyspecks on a balloon" metaphor. But raisins in cupcake dough is okay too.

But the empty space that is expanding is just that:empty space. "Aether" was supposedly disproven by the Michelson Morely Experiment way back in the late Nineteenth Century.

Except that they seemed to have reinvented a concept a little like aether recently: the Higgs Boson.

The Higgs pervades space, and it gives matter mass. And as matter moves through space it collides with more higgs bosons and gets more massive (hense the increase in mass as the velocity of matter approaches the speed of light). These tiny particles that prevade space sound a little like how the Victorians described aether.

I am aware of this, but sometimes it is easier to give things a name; "nothing expanding in to another nothing" can be hard to wrap your mind around, and becouse the higgs field can be seen as "kinda-sorta like aether", i chose that word.