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Speed of Light Inconstant?
DHR writes "Australian scientists have discovered that light isn't quite as fast as it used to be." We've done previous stories on these findings. Those of you with subscriptions to Nature can read the actual paper, the rest of us will just have to suffer.
So, does that explain the ever changing warp scale in Star Trek?
Fascism starts when the efficiency of the government becomes more important than the rights of the people.
I've noticed it takes a while for flourescent lightbulbs to turn on. I guess all of the technology bloat has finally taken a noticable performance hit on light.
eh their mate, thats not a light.
Now that's a light.
> "That's illegal. It would be like a cup of coffee sitting on your desk getting hotter," Lineweaver says
Placing a coffee cup on top of my laptop and running Microsoft Outlook provides the exactly same effect. Where can I get my Nobel prize?
There were a group of people in a room of different professions, and a theorem was put forth onto the board that stated that all Odd Numbers Are Prime. Each person was supposed to disprove this.
The mathematician started off by looking at each number.
1, 3, 5, 7, 9.... 9 is not prime, the theorem is false.
The social worker turned in a long sheet of paper going "2 is prime, 4 is prime, 6 is prime..." etc.
The physicist turned in the following:
1... 3... 5... 7... 9 (Experimental Error), 11, 13.....
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
One possibility, though, is that the structure of the vacuum in space has changed. This is where we get into the rather spooky world of quantum physics. When light travels through a medium other than a vacuum, such as glass or water, it slows down. A vacuum, far from being empty, is teeming with quantum "virtual" particles that flit in and out of existence.
Sometimes those particles become real, such as under a strong electric charge, Lineweaver says. If the vacuum of space is changing uniformly across the universe, just as the universe is expanding uniformly, it could affect the speed of light.
Well... this was the hypothesis that was given in the article... and from the looks of this, it seems that there is a possibility that light didn't slow down at all. Here he explains that it is the medium that light is travelling in that is slowing it down. So light's top speed in a vacuum may still be the same... c, but the medium, the universe, is changing. Who knows.
But if light is slowing down, then that faster than light travel maybe possible. However, how the hell do you see anything when your going faster than any signal? Well... maybe you can communicate with the spooky particles and get instant communication while travelling at faster than light speeds. Of course you'd best be sure your data arrived promptly, as you'll never see the planet you just rammed.
Back in my day, light was blimblamming all over the place! We had GOOD light in those days. Yessiree, you couldn't go outside with your onion strapped to your belt (as was the fashion at the time) without getting knocked over by rays of light all the time! Not like today's LAZY light, mind you.
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Bleah! Heh heh heh... BLEAH BLEAH!!! Ha ha ha ha...
I knew this performer once. Her stage name was "Infinity". I always wanted to take her out to dinner, just so when they said "how many in your party?", I could say "infinity plus one".
If the very early Universe, when all the matter and energy could be contained in a microdot, was such an exotic place that the speed of light approached infinity -- then what happened to the speed of sound?
Two points. First, the idea that the whole mass of the "universe" was contained in a microdot just at the Big Bang isn't really right (depending on what you mean by "universe"). The whole mass of today's observable universe, yes. But if you take the cosmological models at face value, the universe is probably infinite in extent, and always was (at least as far back as you can go without worrying about unknown theories of quantum gravity). It's more accurate to say that the density of the universe approached an arbitrarily large value; then you don't have to worry about a "smaller infinity" or similar.
Now, to what you actually asked: the speed of sound is not a fundamental quantity the way the speed of light is. "Speed of light" generally means "speed of light in a vacuum", which according to standard theory is a fundamental contant. (In material other than vacuum, light tends to travel at speeds less than the "speed of light".) Sound doesn't travel in a vacuum, but needs a medium to travel through. It's speed is entirely dependent on that medium. What we call the "Speed of sound" (when, say, timing distance to lightning strikes based on the delay before we hear the thunderclap) is the speed of sound in air at a typical density and pressure found on the surface of the Earth. The speed of sound in water is a lot higher. In rock, higher still.
In the very early universe, I would expect the speed of sound to be very, very high, but it will always be less than the speed of light in a vacuum (whatever that value happens to be at any given moment).
-Rob
The reason Astronomers don't want to accept this is becuase it would change the nature of every cosmological theory they have. They've invested large amounts of time in old theories, why should they learn new ones? It's all about ego for them.
While there is a possible grain of truth in what you say, it's probably vastly overstated.
It would be better to say that extraordinary claims require extraordinary proof. To almost everybody, the claim that the fine structure constant has been changing is pretty extraordinary, and as such requires pretty solid proof before any measurable fraction of people who care about these things will casually accept it.
There is a danger in the iconoclastic argument. Yes, if a new truth is revolutionary and will require everybody to throw out everything they know, everybody will resist accepting that truth. It does not follow that therefore every revolutionary idea which meets widespread resistance must be a new truth.
-Rob
As other people have pointed out, the fine-structure-constant-is-changing work came out a year ago. The fine structure constant is a function of the speed of light, c, and the charge of the electron, e.
This particular article argues that e can't change much over time without causing inconsistencies, so they conclude that c must have been changing. No new data, no new support for the constant-is-changing theory. (And the original study was pretty damn flawed. This paper isn't bad.)