# The Naked Scientists Forum

### Author Topic: Breaking the speed of light – theoretically.  (Read 1603 times)

#### Gerry

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##### Breaking the speed of light – theoretically.
« on: 20/07/2010 08:15:44 »
I first want to say that I am dumb.  I have no brain for academics.  My math may be – and probably is – wrong.  Please ignore the math if its wrong and comment purely on the theory I’m giving.

If you have a disk spinning on an axle – like an old Vinyl LP, for instance, then a point on the disk closer to the axle will spin at a slower speed than one further out.  IE – the further away from the axle you are, the faster it goes, right?

So now, how do we apply this to breaking the speed of light? If I have a laser-beam, one of those nifty things the astronomy guys use to point out stars, and I wave it about, how fast does the "tip" of that light-beam move?

I've worked out that at a speed of 10 000 revs/second - pretty fast but certainly not impossible with a good rig -  and at a beam distance of about 4772 meters – again, not too difficult for a focused beam of light – the tip of the beam of light will equal the speed of light.  The further that beam goes, the faster the tip goes.  If I make my beam 10 000 metres long, I would have more than doubled the speed of light.

Okay, where is the flaw in my theory?  I can't possibly be right.  I'm too dumb for this.

Alternatively, have I just gotten myself the Nobel prize for physics?  Have I just broken the speed of light?  Or do I just need more sleep?

What I can see happening is "lag" – that instead of the beam being straight, it will start "bending backwards" as it reaches the greater lengths.

#### imatfaal

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##### Breaking the speed of light – theoretically.
« Reply #1 on: 20/07/2010 17:16:12 »
Gerry

Nothing is actually travelling more than the speed of light.  The beam of light leaving your laser is going at the speed of light - if you think of light in its packet/quantum format; each lump of light emitted by the laser is going a shade under 3*10^9 m/s directly out of the laser, and each lump of light is still doing the same speed in the same direction when it has travelled 1mm, 1m, 1km etc.   a beam of light is a bit of a misnomer - it is not a beam, a physical entity the end of which travels a distance of 2Πr per revolution.

This potential paradox is often phrased in terms of sweeping a laser across the face of the moon from the earth; but the light that is incident on one section of the face of the moon has nothing to do with the light on a separate section.  the crux of the matter is that no information is transmitted at higher than the speed of light.  this same paradox is also viewed through the speed that the cross point of the two blades of a pair of scissors move - it can move very quickly, but carries no information.  Hope the above made sense - nothing tangible has travelled faster than light and no information conveyed faster than light.

Matthew

#### The Naked Scientists Forum

##### Breaking the speed of light – theoretically.
« Reply #1 on: 20/07/2010 17:16:12 »