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

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If you were at the edge of the universe, everything would look to you much as today. Except, of course, you would not be on Earth.

To someone at the edge of the universe, our galaxy would be on the edge of the universe and destined to be beyond the edge soon because of the expansion of space between us and them.

but a photon can violate the direction of the expansion of space...it can go with said expansion or against its direction...and its speed remains C
C is unchanging
Space's expansion rate is increasing

pls elaborate

Since its already been stated that space can expand faster the light then the "speed" of space can be faster than light, therefore the speed of space is not the same as that of light.

So the statement "the speed of light should be called the speed of space" doesnt make any sense.

I am confused. If space can expand faster than the speed of light and Higgs boson populates space does the Higgs boson have to travel at the speed of space?

Is the Higgs boson going along for the ride and not being accelerated?

Ah, the great inflation. I need to read more.

Great subject!

I agree with naturalplastic. Space would not be limited to a specific speed like light is, although it probably has an average speed that the universe is expanding upon.

I thought up a visual model for the expansion of space vs. speed of light issue. You will need a piece of paper to do this though. First, fold the paper in half. Second, going in the same folding direction as before, fold the paper into quarters (it now resembles a fan). Third, touch the first quadrant of the paper with the last one (so that there is two quadrants now folded inside. Fourth, draw a starting point on quadrant four and an arrow going into quadrant one. (That represents a photon traveling at constant light speed.) Fifth, when you unfold the paper, this represents the difference between light speed and how fast space can travel (at the edge of the universe) at the same relative time. It also shows how light energy can be moved relative to where it should have been relative to the original path. Granted, it is not a perfect model, as the movement of space is mostly constant over time (so the light path would not appear to be broken if observed from an outside point, unlike on the paper).

Hubble's Constant.

It's approximately 67 kilometers / second / megaparsec.

That is, for every megaparsec between two points, space is expanding at an approximate rate of 67 kilometers per second.

Speed of space makes no sense because speed = distance/time. Neither of which can exist without space. As space expands, I would assume that as attributes of space, it is safe to think of time and distance "expanding" right along with it.

A "megaparsec" meaning 3.26 million light years.

Einstein deduced that nothing goes faster than light in a vacuum from how our world behaves, and this has subsequently been considered a universal constant, but it isn’t clear why this is the case. Currently: “the speed of light is a constant because it just is, and because light is not made of anything simpler.”

To answer “Why can’t things go faster and faster?” with “Because they can’t” is hardly satisfactory. Light slows down in water or glass, and when it moves in water we say the medium is water, and when it moves in glass we say the medium is glass, but when it moves in empty space we fall silent. How can a wave vibrate nothing? There is no physical basis for light to move in empty space at all, let alone define the fastest speed possible.

If the physical world is a virtual reality, it is the product of information processing. Information is defined as a choice from a finite set, so the processing changing it must also be finite, and indeed our world does refresh at a finite rate. A supercomputer processor refreshes 10 quadrillion times a second, and our universe refreshes a trillion, trillion times faster than that, but the principle is the same. As a screen image has pixels and a refresh rate, so our world has Planck Length and Planck Time.

In this scenario, the speed of light is the fastest speed because the network can’t transmit anything faster than one pixel per cycle—i.e., Planck Length divided by Planck Time, or about 300,000 kilometers per second. The speed of light should really have been called the speed of space.

How is that better (more accurate) than, "the speed of light in a vacuum"? What length are you measuring the speed of space against if not itself?

He is not even talking about: the speed at which empty space itself expands.

Apparently he is talking about the maximum speed at which the fundamental forces of nature move through space ( the speed ON the highway, not the speed limit that the highway itself can move).


Gravity moves at the speed of light, as does all electromagnetic radiation. Visible light (a type of EMR) was thing the first "thing" to be discovered as having the speed we call "the speed of light" ( a couple hundred years ago they were event sure if light didnt move an infinite speed). So thats why the speed is called that.

And its not quite true to say Einstein "gave no reason" for the SOL being the cosmic speed limit. The reasons are mapped out in his theory: mass increases as you approach light speed so more energy is need to further accelerate to get closer to light speed, conquering the last decimal would take more than all of the energy in universe.

Isn't that what I said back on page 1???

Edit: that was *supposed* to be a 'sticking my tongue out' emoticon. colon-dash-capital 'P'.

The bit about mass accumulating as you approach the SOL?

Um..yeah? I didnt say that you didnt say it.


And, as I said above, the reason for that is that when your spaceship approaches light speed you start to run into more higgs bosons which piles on your mass. Kinda like a bunch of damned speed bumps.

There is another thing that I need to add to this topic. While reading a book (A Universe from Nothing), it came to me that there is a very specific reason why matter cannot go faster than the speed of light. Per Albert Einstein's Theory of Relativity, all charged particles (protons, electrons, quarks, etc.) would become their anti-matter opposites if they somehow exceeded the speed of light. This part is based upon his mathematical equations that show the reversion happening at that point. The moment that the anti-matter forms, the particles would very likely undergo annihilation processes with regular matter unless kept in an absolute vacuum. Outer-space is not an absolute vacuum as there are usually a few particles of matter scattered in every cubic meter of space. So the net result would be a transformation of matter into light energy (likely gammas) via an anti-matter intermediate stage (E <--- mc^2).

I can see where the same process would occur even if the particles were not charged (ie. neutrons), as unbound neutrons can undergo beta decay processes leading to charged particle production.

Particles thought to go faster than light are called tachyons (if they even exist at all). I've never heard it claimed that they would be antimatter.

As far as I know, antimatter does not travel faster than light. It is often thought of as matter traveling backwards in time but that is not the same as traveling faster than light.

Of course, if tachyons do exist, then it might not be so far fetched to imagine anti-tachyons, I guess.

^
This.

An astronomy professor I had explained that tachyons not only exceed the speed of light but that they "like" to go infinite speed. Their mass at infinite speed is the equivalent to the "rest mass" of ordinary matter. And that its as infinitely difficult to bring tachyons DOWN to the speed of light as it is bring normal matter UP to the speed of light.

But he said that tachyons "have not been observered. And exist only in the theoretical never-never land of physics."

One thing though. If tachyons do exist, and do routinely live at above light speed then they would indeed be "traveling backward in time" - I would imagine-in order to abide by Relativity Theory.