Tachyons?

[june5197]

Nothing can exceed the speed of light (as we all know). However, recently I have been drawn towards the theory of tachyons.

 

Supposedly, they should exist beyond the speed of light and never be able to slow to reach it. Moreover, the particles would travel backwards through time.

I don't understand, at all, if we were to detect them... How so? Tachyons would only exist for an instance, therefore there mustn't be a way to follow and detect any one of these particles.

 

I am not particularly smart and am young so I just can't justify that even if they are there... Would we ever prove them? If so, how?

Edited August 6, 2014 by june5197

[Delta1212]

Why would tachyons only exist for an instant?

[Strange]

 

Supposedly, they should exist beyond the speed of light

 

More exactly, they could exist. There is no evidence that they do.

 

There have been experiments to try and detect tachyons by looking for the Cherenkov radiation they would produce (this is the optical equivalent of a sonic boom, produced when something travels faster than the speed of light in a vacuum).

 

 

Moreover, the particles would travel backwards through time.

 

They would not travel backwards through time. But they would, in theory, allow communication back through time (under very special conditions).

[swansont]

Nothing can exceed the speed of light (as we all know). However, recently I have been drawn towards the theory of tachyons.

 

Supposedly, they should exist beyond the speed of light and never be able to slow to reach it. Moreover, the particles would travel backwards through time.

I don't understand, at all, if we were to detect them... How so?

 

Well, that's the problem. If they obey the physics we understand, it means having an imaginary (mathematically) mass to give it real energy, or normal mass means it has imaginary energy. But imaginary mass or energy doesn't correspond to anything physical.

[ajb]

Standard tachyons have negative mass squared and there is noting written into special or general relativity that by itself rules out such particles. Classically it seem that they could be realised in nature.

 

However, when you throw quantum mechanics into the picture you realise that tachyons are inherently unstable and will decay to normal particle very quickly. A system containing tachyons will quickly and spontaneously lower its energy producing "condensate" of standard particles. This process is known as tachyon condensation.

[june5197]

 

More exactly, they could exist. There is no evidence that they do.

 

yes, this I know, that was my original question of 'do they exist'.

 

They would not travel backwards through time. But they would, in theory, allow communication back through time (under very special conditions).

I heard in a documentary that they would because of the speed of their possible existence? But it was probably not what they meant, what you've said sounds more realistic.

 

By the way, i'm not too sure on how to quote, so this reply may look odd.

[Delta1212]

I heard in a documentary that they would because of the speed of their possible existence? But it was probably not what they meant, what you've said sounds more realistic.

 

By the way, i'm not too sure on how to quote, so this reply may look odd.

Be careful with science information you come across in documentaries and on TV. They tend to sensationalize things a bit (or a lot) and a lot of nuance tends to get lost in favor of making things sound cool.

[june5197]

Be careful with science information you come across in documentaries and on TV. They tend to sensationalize things a bit (or a lot) and a lot of nuance tends to get lost in favor of making things sound cool.

I watched a lecture by Neil deGrasse Tyson which influenced my idea...

I see where you are coming from, makes sense.

[ajb]

I heard in a documentary that they would because of the speed of their possible existence? But it was probably not what they meant, what you've said sounds more realistic.

The statement is something like "for an tachyon it is always possible to find an inertial frame of reference such that the tachyon is moving backwards in time".