Faster than light

[skulldude]

I have heard that some hypothetical particles called "Tachyeons" travel faster than light. Is it true.

[Daecon]

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

 

Is there a Science-specific version of Wikipedia anywhere? There should be...

[CaptainPanic]

You have answered your own questions when you stated that the Tachyons are hypothetical. (Hypothetical means that no evidence was found yet - but some people expect it is possible).

 

I generally associate the word "Tachyons" with Star Trek. Tachyon-beams are the default solution for any problem in Star Trek, The Next Generation.

[swansont]

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

 

Is there a Science-specific version of Wikipedia anywhere? There should be...

 

Note the mention of imaginary mass and the difficulties it introduces.

 

As an aside, this points out a problem with wikipedia. This is the first time I ever heard the term "bradyon." Someone has coined a new term, or dug up an obscure one, and injected it into the article. (Googling on it gets about 4000 hits. Tachyon gets 2,000,000).

 

I think "bradyon" deserves to die (or perhaps die again). Even the youngest one, curls and all.

[YT2095]

quick question;

 

If said particle travels faster than c, then wouldn`t it have to have come from the Future also?

[Daecon]

No, just from further away in the same amount of time.

[YT2095]

that strikes me as a Very Newtonian view, I`m thinking from a relativistic perspective.

[Daecon]

Sorry, I'm not sure I follow...

 

If you're measuring time as dependent on light, then yeah. But isn't that like the thing with the two supernovas happening at different times, the first one 2 years ago in a galaxy 2 light-years away, and another 1 year ago in a galaxy 1 light-year away, so here on Earth they just look like they're happening at the same time.

 

(Yes I know those distances are ridiculously small, I was just making a point.)

[swansont]

For v>c the gamma term becomes imaginary, so that means the time dilation and length contraction are imaginary as well. I don't know what that means, physically. But there's a lot of physics that relies on the square of terms, so you're back to dealing with real numbers again.

 

Switching the direction of time is a symmetry operation. There's charge, parity and time, and you can flip the time if you also flip CP, which is how you get antimatter looking like regular matter going backward in time. Assuming you can do the same thing to tachyons, then it just becomes a convention of what you call a tachyon and antitachyon, AFAIK.

[YT2095]

interesting that you should mention an "Anti-Tachyon", I`v been thinking further about this and came up with a similar idea myself in order to make other things "work".

 

it`s lead me to another question (I hope I`m not seen as Hijacking this thread).

 

since it`s Known that Anything with mass that gets to the speed of c gets Infinite Mass, wouldn`t therefore something that travels Faster either have to have Negative mass, OR if it had Mass, would "Vanish" if it slowed to below c?

 

I`m not a Physicist, I`m only using Logic, so forgive my question/hypothesis if it seems "out there".

[Daecon]

since it`s Known that Anything with mass that gets to the speed of c gets Infinite Mass, wouldn`t therefore something that travels Faster either have to have Negative mass

 

I had the same thought!

[thedarkshade]

I have heard that some hypothetical particles called "Tachyeons" travel faster than light. Is it true.

It's just a theory! Their existence has yet to be confirmed!

 

They indeed need to be going faster than light, because when they're traveling exactly the speed of light, their energy is infinite, as shown:

 

[math]E=\frac{m_0c^2}{\sqrt{\beta^2 -1}}[/math]

 

and one of their strange characteristic (as you can see from the equation) is that, the faster they travel, the less energy they have. This weird characteristic of them is because the Einstein factor for them is [math]\sqrt{\beta^2 - 1}[/math] instead of [math]\sqrt{1 - \beta^2}[/math].

 

They surely have not been send to the speed of light and then exceeded it, since you need infinite energy to do that, but (if they exist) they are thought to be born traveling faster than light. But that's just theoretical!

[D H]

It's just a theory! Their existence has yet to be confirmed!

Tachyons are just a conjecture. They are not a "theory" for the very reason that "their existence has yet to be confirmed!".

 

But that's just theoretical!

Nothing theoretical here, move along.

 

=======================

 

As an aside, this points out a problem with wikipedia. This is the first time I ever heard the term "bradyon." Someone has coined a new term, or dug up an obscure one, and injected it into the article.

As a double aside, if you follow the wiki link to the article on "bradyons" you will find yet another coined term, "luxon".

[YT2095]

I think Everyone here so far is Quite Aware that this is purely Hypothetical, however it shouldn`t detract from the actual Mechanics of it and the application of a little Thought based upon what IS known.

 

that Is after all partly what this forum is about, the Exploration of Ideas from a Scientific perspective

[D H]

I objected to the use of the word "theory". This is a scientific forum, so we should use scientific terminology.

 

Why so picky? Because abusing the word theory is exactly one of the techniques creationists use to prey on a gullible public. They conflate the scientific meaning of "theory" in "Theory of Evolution" with one of the lay meaning of the word, "wild-ass guess". The argument is something along the lines of "It's the 'Theory of Evolution'; we shouldn't be teaching evolution as if it were a fact. It's only a theory, after all. Schools should teach our theory as well."

[Klaynos]

interesting that you should mention an "Anti-Tachyon", I`v been thinking further about this and came up with a similar idea myself in order to make other things "work".

 

it`s lead me to another question (I hope I`m not seen as Hijacking this thread).

 

since it`s Known that Anything with mass that gets to the speed of c gets Infinite Mass, wouldn`t therefore something that travels Faster either have to have Negative mass, OR if it had Mass, would "Vanish" if it slowed to below c?

 

I`m not a Physicist, I`m only using Logic, so forgive my question/hypothesis if it seems "out there".

 

Imaginary mass, Swanson makes a mention to it above, I assume it is talked about in the wp page.

[swansont]

I objected to the use of the word "theory". This is a scientific forum, so we should use scientific terminology.

 

Why so picky? Because abusing the word theory is exactly one of the techniques creationists use to prey on a gullible public. They conflate the scientific meaning of "theory" in "Theory of Evolution" with one of the lay meaning of the word, "wild-ass guess". The argument is something along the lines of "It's the 'Theory of Evolution'; we shouldn't be teaching evolution as if it were a fact. It's only a theory, after all. Schools should teach our theory as well."

 

The phrasing "just a theory" should make one's word processor explode. IMO.

 

———

 

It's no problem exploring the idea in a scientific context, but you have to address the issue of how a tachyon would behave and interact, and deduce how we would detect such a particle. If they don't interact with normal matter, how would we ever know they exist?

[Phi for All]

The phrasing "just a theory" should make one's word processor explode. IMO.

Seconded. We're going to start working on making this a reality in the very near future. Ka-BOOM!

[YT2095]

oh well done Phi! now Everyone`s gunna know what I`v been spending time away from here Working on!

[xptoast]

Theory...This is from dictionary.com

 

 

the·o·ry /ˈθiəri, ˈθɪəri/ Pronunciation Key - Show Spelled Pronunciation[thee-uh-ree, theer-ee] Pronunciation Key - Show IPA Pronunciation

–noun, plural -ries.

1. a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity.

2. a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact.

3. Mathematics. a body of principles, theorems, or the like, belonging to one subject: number theory.

4. the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.

5. a particular conception or view of something to be done or of the method of doing it; a system of rules or principles.

6. contemplation or speculation.

7. guess or conjecture.

 

That looks like guess to me. Sorry it just bugs me when people wish to meddle with their own language and meanings. Even laws of physics are not perfect. Such as gravity formula. Its not perfect but sure as heck got us to the moon and back. Science is not perfect. Its just mostly right. Not all right.

[swansont]

Theory...This is from dictionary.com

 

 

the·o·ry /ˈθiəri, ˈθɪəri/ Pronunciation Key - Show Spelled Pronunciation[thee-uh-ree, theer-ee] Pronunciation Key - Show IPA Pronunciation

–noun, plural -ries.

1. a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity.

2. a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact.

3. Mathematics. a body of principles, theorems, or the like, belonging to one subject: number theory.

4. the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.

5. a particular conception or view of something to be done or of the method of doing it; a system of rules or principles.

6. contemplation or speculation.

7. guess or conjecture.

 

That looks like guess to me. Sorry it just bugs me when people wish to meddle with their own language and meanings. Even laws of physics are not perfect. Such as gravity formula. Its not perfect but sure as heck got us to the moon and back. Science is not perfect. Its just mostly right. Not all right.

 

 

dictionary.com is not a technical resource, but what's wrong with 1? That's referring to the scientific use, and does not mean "guess."

 

Calling something a law in science does not mean that it's perfect (something that we are discussing here, just that it's been observed to hold, and there's a relatively simple formula for it.

 

Followups to this topic should go in linked thread, not here. I've copied the these two posts over to there.