36 replies to this topic

[SolidSpartan117]

Here is a subject I love, earlier this month two German scienctists claimed they had broken Light Speed! What I dont get is why haven't they agreed to prove this claim? Lets look at it this way, if you were to travel the speed of light, time stops. Not only does time stop, but your body mass is envinity. Now if you were to travel faster than light speed, you would acctualy arrive at your destination before you left? Maybe I'm confused but can anyone shed some light on the situation?

[Dauth]

Firstly http://forum.cncrene...showtopic=18953

Secondly, Cherenkov postulated particles faster than the speed of light in certain media.

Light travles at c (3*10^8 ms^-1) in free space.

In air it's a bit slower, water slower still. however in water it's possible to give an electron enough energy to move faster than light in water. In this case Cherenkov radiation is emitted.

Another way is the expansion of space in the early universe, while something can't travel faster than light in free space, if the space itself is expanding, nothing in physics can stop it.

Proving the claim would be something to watch, since it would indeed cause a black hole...

[SolidSpartan117]

Where do you get your info? Light speed is Light Speed, the only things that can trabel this speed are Transmissions or Light itslef?

[Dauth]

4 years of studying physics with theoritical physics in the University of Manchester.

[SolidSpartan117]

Ok then, that put me in my place (Bows down to genius), but all I am trying to say is light is light and doesn't slow down ever.

The speed of light = 299 792 458 m / s

speed of light in a vacuum is an important physical constant denoted by the letter c for constant or for the Latin celeritas ("swiftness"). It is the speed of all electromagnetic radiation, including visible light, in a vacuum. More generally, it is the speed of anything having zero rest mass.

In metric units, the speed of light in vacuum is exactly 299,792,458 metres per second (1,079,252,848.8 km/h). The fundamental SI unit of length, the metre, has been defined since October 21, 1983, as the distance light travels in a vacuum in 1/299,792,458 of a second; any increase in the measurement precision of the speed of light would refine the definition of the metre, but not alter the numerical value of c. The approximate value of 3×108 m/s is commonly used in rough estimates. In imperial units, the speed of light is about 670,616,629.2 miles per hour or 983,571,056 feet per second, which is about 186,282.397 miles per second, or roughly one foot per nanosecond.

The speed of light when it passes through a transparent or translucent material medium, like glass or air, is slower than its speed in a vacuum. The ratio of c to the observed phase velocity is called the refractive index of the medium. General relativity explains how a gravitational potential can affect the apparent speed of distant light in a vacuum, but locally light in a vacuum always passes an observer at a rate of c.

[Medve]

The sudden expansion of the universe is called inflation in english too? I am very interested in science, and I have a friend who is to take your way Dauth(studying physics). We always have discussions about astrophysics it's his favourite. . Oh and if we don't "find" lots of dark material and confirm that the universe will expand as hell to the end, then we'll probably be expanding at the last seconds at light speed. (the expansion speed is getting higher and higher as it speeds up)

Medve

[Chyros]

SolidSpartan117, on 6 Feb 2008, 22:28, said:

light is light and doesn't slow down ever.

Well physics isn't my best subject but doesn't light have characteristics of waves as well as particles? Because that would explain light being slower in water, light bumping into water molecules, transferring a tiny bit fo kinetic energy and thus slowing it down. I'm guessing all this but I find it sounding logical when I tell it to myself .

[Dauth]

Hmm logic + relativity, not the best combination.

I think it may be something to do with the interactions but I'm not sure which characteristics cause the light to slow.

@SolidSparta117, all the information there is correct, but I assumed that sort of knowledge when I posted my response.

@Medve, sudden expansion very early on is called inflation (and is the reason why the cosmic microwave background radiation is the same in all directions - well close enough).

Yes dark matter is thought to be driving the expansion of the universe - don't worry not in our lifetimes, but i'll have more detail after my course on the early universe.

For those interested, light obeys the wave equation, use wiki it's correct as of this post, and in free space this can be derrived from Maxwell's equation very easily.

[SolidSpartan117]

Yeah, Light is waves, like gamma rays and so on, but the Germans believe they have bronke the light barrier??? LMAO

[Teron]

Im no physicist, but if you are refering to this, then I think that microwave photons, which, afaik, do not possess any mass, can in fact travel as fast as light. Just like neutrinos(?) can.

Edited by Teron, 07 February 2008 - 01:48.

[Dauth]

Photons are massless (so are all particles according to the standard model. but don't get me started).

It's known as the EPR paradox and i'll explain it when I have more time, that being said reflections can travel faster than the speed of light, however information cannot, I doubt very much they'll get anything through it.

[CodeCat]

Am I the only person relativity actually makes sense to? I really don't see anything strange or unexpected with it...

[Dauth]

Special theory make sense, the crazy stuff appears in the maths of general theory. So much so I feel I failed the exam on it.

[General Kirkov]

What about Star Trek? They go the speed light +

Disreguard that comment

From a Historical perspective someone as always claimed that something was imposible, until someone did it. Just wait out acheiving faster than light travel may still be acheived.

[CodeCat]

There's a difference between technical unfeasability and physical impossibility, though.

[Babylon]

General Kirkov, on 7 Feb 2008, 16:08, said:

Just wait out acheiving faster than light travel may still be acheived.

This is why I think it will not happen:
Something that has mass will never go at the speed of light because it will take an infinite amount of energy.
Something that has no mass will never go faster then the speed of light, because you can't accelerate it.

[Reaper94]

from what ive heard if one was to go with the speed of light youd flatten yourself (or catch fire) im not a scientist or nutting this is just wat a mate told me but basics that i understand state that the momentum youd gather is enough to flatten yourself. Also someone (credible) told me that the light we say has taken 8 mins to reach us.

Back to (un-credible?) info, i do belive hearing yo would reach the destination before you left it and youd catch fire from over-heating due to the strain on your body.

For example take a Suzuki Hayabusa (also known as the GSX1300R)

The hayabusa (bugly as biukers know it) it one of the fastest road legal bikes out. The point of this? At stock a new one will do 200 mph. if one added nitrous or a turbo/supercharger to it, it would hit around abouts 220 mph, in human terms that 98.3488 meters per second thats a kilometer in just over 10 seconds; imagaine the standards of the bbike to withstand that

do u REALY think a human cld withstand more than that?

[Sgt. Rho]

as you aproach light speed, your mass increases. so at such a speed as light speed, you would be squished by your mass.......

[SolidSpartan117]

As you approach light speed you mass increases to almost infinity, and when you hit light speed your mass is infinite, but people are claiming that if we were able to create Cold Fusion (Which is basicaly endless energy) we would have enough to push that mass, but in space there is no gravity therfore no mass, so infinite energy isn't needed unless you are traveling around planets or somthing. Also dont forget that when traveling at light speed a single piece of dust could crush a giant ship. Now as for theese particles traveling at light speed, that is something I find immposible, even through a particle accelarator scientists have still not reached light speed.

[Dauth]

NOO Cold fusion is not endless energy.

Energy cannot be created or destroyed.

Energy is equilivent to mass, so an intense amount of energy also has a gravitational field, infited energy = infite mass = end of the universe.

[SolidSpartan117]

YES, I do know that fact, and I also know that cold fusion creates infinite energy, and why if they succed we will all die

[Dauth]

Infite energy does not exist, it's a flawed concept that really should be kept out of scientific discussion.

Fusion released dramiatcially more energy per nucleus.

Fission you get about 200eV / nucleus
Fusion you get about 2.2 Mev / nucleus.

[SolidSpartan117]

Well, we could argue about this all day, I believe fusion is possible, you dont. Lets leave it there

[Dauth]

No I know fusion is possible, its how nuclear weapons work.

But Infinite energy is stupid, lots of energy makes sense, fusion is better than fission but a time away, however the energy fusion relaeses still won't get you to light speed, just closer.

[SolidSpartan117]

I dont see how they are going to control such a massive energy release