Faster than light possible

[FeltRipper]

Ok bear with me according to einstein nothing can go faster than light. as any any object at that speed would gain infininate mass which would obvioulsy be a problem. However as i understand it Black holes are formed by having such a strong gravitational pull that even light cannot escape. Now what this implies and I stress implies because we do not know for sure, that light has some mass for the gravity to effect. By logical reasoning this means that light traveling away from the black hole will have a force exerted on it strong enpough to slow and then reverse its direction taken another way light heading towards the black hole will have its speed increased by the same force. From this I come to two conclusions:

firstly that photons have mass

and

secondly that faster than light is possible Very hard but possible as the idea of mass increasing as speed increases upto the "impossible speed of light" to be completely incorrect because simply put if a photon has mass then it is under the same rules as any other mass which would lead to light having infinate mass.

 

Hope that makes sense thought about this for a while and cant see a flaw but please feel free to comment

[toastywombel]

Ok bear with me according to einstein nothing can go faster than light. as any any object at that speed would gain infininate mass which would obvioulsy be a problem. However as i understand it Black holes are formed by having such a strong gravitational pull that even light cannot escape. Now what this implies and I stress implies because we do not know for sure, that light has some mass for the gravity to effect. By logical reasoning this means that light traveling away from the black hole will have a force exerted on it strong enpough to slow and then reverse its direction taken another way light heading towards the black hole will have its speed increased by the same force. From this I come to two conclusions:

firstly that photons have mass

and

secondly that faster than light is possible Very hard but possible as the idea of mass increasing as speed increases upto the "impossible speed of light" to be completely incorrect because simply put if a photon has mass then it is under the same rules as any other mass which would lead to light having infinite mass.

 

Hope that makes sense thought about this for a while and cant see a flaw but please feel free to comment

 

Photons have mass, but only because they travel so fast. The rest mass of a photon is zero. Matter on the other hand has a rest mass of greater than zero. That is why it is impossible to get matter to travel at the speed of light. Here is a link to a good set of videos that are on the scienceforums.net youtube channel that explains relativity quite well.

 

Furthermore, faster than light transportation would not be possible. If you mean by moving an object through space-time. Now faster than light is possible if you have space-time move around an object, but the technology to warp and manipulate space-time in such a way is a long way off of being developed. The other box you would open by going faster than the speed of light is the fact that you would go back in time.

Edited January 5, 2010 by toastywombel

[Severian]

Photons have mass, but only because they travel so fast. The rest mass of a photon is zero.

 

Photon's have no rest frame, so 'rest mass' is ill-defined for a photon. Photons have zero mass, period. (Or, to qualify that, the photon's mass is so small it has never been measured.)

[FeltRipper]

thanks guys but saying that photons zero mass or only have mass because they are moving so fast makes no sense gravity from say a black hole only works on mass and also if mass increases infinately at speed of light there must be a mass to increase no matter how small and even the smallest mass no matter how small increased by infinity would be infinate not tiny ergo either our idea the affect of light speed on a mass is incorrect or light has infinate mass.

 

The greatest achievement in science is the understanding that we know nothing!

[Klaynos]

Gravity bends space.

 

Light follows straight lines of space.

 

If the space is bent the straight line is bent.

 

It appears that the light is traveling in a curve, and is effected by gravity.

[Sisyphus]

To elaborate, inside the event horizon of a black hole, space is bent so much that any straight line (and thus any path that light can take) just leads elsewhere inside the event horizon, and never outside. That's why nothing can escape, because there is literally no direction that is "out."

 

Photons do not have mass. The confusion probably stems from the fact that they do have momentum, which is confusing if you're used to thinking of momentum as just mass*velocity.

[michel123456]

Haha.

Photons have no rest mass, but they have mass when moving. They cannot stand at rest, so "rest mass" for a photon is meaningless. So, because they cannot stand still, they do have mass, but no they don't. Very simple.

"Gravity bends space", so space has mass. Hum.???? wrong. Sorry.

Have you ever made a Mass/Speed diagram ? Mass increases with speed. But speed is frame-dependent. So Mass is frame-dependent too. Rubbish. No it is not. Oh come-on.

[FeltRipper]

thanks guys. its funny that the more indepth into these things you go the more it is based on guess work. as how do we prove space is bent without actually going there because we have no way of accurately measuring spaces shape. The universe is a huge and magnificent mystery. I am lucky enough to see two supernovas happen and it boggles the mind to think i was watching something that huge yet it happened many thousands of years ago. The entire planets astronomy is so far out of date it boggles the mind. also i cant remember where i saw it but i remember scientists slowing the speed of light at super cold temperatures through a crystal to around 38 miles an hour.

just found websit take a look:- http://www.jupiterscientific.org/sciinfo/slowlight.html

 

I find it very frustrating that we will probably never truely understand the universe as it is like an amoeba trying to understand chess. Like star trek said "Space the Final frontier" Searching for answers is sometimes more rewarding than finding out especially if you dont like the answer! lol World Round and earth rotates round sun spring to mind!

[Sisyphus]

We haven't directly observed a black hole (and we couldn't directly observe the inside of one even if we found one), but you can observe the curving of space due to mass:

 

http://en.wikipedia.org/wiki/Tests_of_general_relativity

 

Theories evolve and obviously there is much we don't know, but calling something that has made so many accurate predictions mere "guesswork" is not really fair.

 

The "slowing light down" thing is off topic, but for what it's worth, it's actually not slowing light down. When light "travels" through a fluid, it's really photons being absorbed by the material, than other photons being emitted and reabsorbed, etc. in a chain reaction. This causes a delay every time, and so overall the light appears to be travelling "slower." Sometimes a lot slower, as in that case. However, individual photons are still all traveling as fast as they always do.

[Klaynos]

Haha.

Photons have no rest mass, but they have mass when moving. They cannot stand at rest, so "rest mass" for a photon is meaningless. So, because they cannot stand still, they do have mass, but no they don't. Very simple.

 

They have no rest mass, which is nearly always just referred to as mass, this is because relativistic mass is not required to formulate relativity. You can do it all only just rest mass, meaning that relativistic mass is redundant and certainly not fundamental.

 

"Gravity bends space", so space has mass. Hum.???? wrong. Sorry.

 

General relativity shows that acceleration and gravity both bend space-time, it itself does not require mass for this to occur.

 

Have you ever made a Mass/Speed diagram ? Mass increases with speed. But speed is frame-dependent. So Mass is frame-dependent too. Rubbish. No it is not. Oh come-on.

 

Which bit is rubbish? And for the sake of understanding and fitting to the commonly accepted terminology, please in this conversation state relativistic mass when that is the mass to which you are referring.

[Severian]

Sometimes I despair of these forums.

 

Have you ever made a Mass/Speed diagram ? Mass increases with speed. But speed is frame-dependent. So Mass is frame-dependent too. Rubbish. No it is not. Oh come-on.

 

A mass-speed diagram would be a bit boring for photons since they only travel at c. As Klaynos says, one normally discusses the mass of massive particles using rest mass, since relativistic mass is frame dependent. In the case of a photon though, you have no choice - rest mass is the only definition of mass for the photon and it is zero, period.

 

If the photon mass were not zero, you would have broken the electromagnetic symmetry and electromagnetism would stop being a long range force. That would really bugger up the universe.

[ajb]

If the photon mass were not zero, you would have broken the electromagnetic symmetry and electromagnetism would stop being a long range force. That would really bugger up the universe.

 

(But can happen in condensed matter physics viz the Meissner effect and an abelian Higgs model)

[ponderer]

Ok bear with me according to einstein nothing can go faster than light. as any any object at that speed would gain infininate mass which would obvioulsy be a problem. However as i understand it Black holes are formed by having such a strong gravitational pull that even light cannot escape. Now what this implies and I stress implies because we do not know for sure, that light has some mass for the gravity to effect. By logical reasoning this means that light traveling away from the black hole will have a force exerted on it strong enpough to slow and then reverse its direction taken another way light heading towards the black hole will have its speed increased by the same force. From this I come to two conclusions:

firstly that photons have mass

and

secondly that faster than light is possible Very hard but possible as the idea of mass increasing as speed increases upto the "impossible speed of light" to be completely incorrect because simply put if a photon has mass then it is under the same rules as any other mass which would lead to light having infinate mass.

 

Hope that makes sense thought about this for a while and cant see a flaw but please feel free to comment

 

 

Comments withdrawn. Sometimes it's better to say nothing.

 

Let's just say, that if you are worried about Korean missle tests, car bombs, kidnappings, or controlling borders...

 

We do not live in a Star Trek world, of nice cuddly people.

Edited February 8, 2010 by ponderer

[StrontiDog]

Ok bear with me according to einstein nothing can go faster than light.

 

There's a little problem of oversimplification in the initial premise, here. It has to do with the medium the mass is traveling through. No matter can exceed the speed of light in a vacuum. Is closer to what Einstein said.

 

It's important, because I've seen the blue glow attributed to Cherenkov Radiation many times, with my own eyes. It isn't even that 'hard' to do. This would be matter exceeding the "speed of light" in ultra-pure, deionized water. The term is misleading, and I can easily see how anyone could become confused by it. We should probably call it something else.

 

Since this thread also talks about the speed of light in a medium other than vacuum, I thought it apropos. The best link to explain how light 'seems' to have a different speed in a translucent media, I found here. It is important to remember, also, that some light that goes into the non-vacuum media never makes it out the other side. There is always some attenuation. If the refractive index of the media was zero. . .well, it would be a vacuum.

 

Bill Wolfe

Edited March 3, 2010 by StrontiDog