Talk:False vacuum

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The first statement in the article, "A false vacuum is a metastable sector of quantum field theory...," doesn't make any sense. The "sector of quantum field theory" is not, itself, metastable. The adjective "metastable" shouldn't refer to the state of a sector of the theory (unless, of course, the theory, itself, is not completely stable).

Likewise for the following statment, "... Simply put, the false vacuum is a state of a physical theory ...". The false vacuum is not the state of a theory.

69.107.143.233 16:36, 25 August 2006 (UTC) D.C. George

You're absolutely wrong. Look in any reference on the subject. –Joke 20:56, 25 August 2006 (UTC)
For example, Coleman and de Luccia, the first line of the abstract reads "It is possible for a classical field theory to have two stable homogeneous ground states, only one of which is an absolute energy minimum. In the quantum version of the theory, the ground state of higher energy is a false vacuum, rendered unstable by barrier penetration." State, sector, vacuum – they're interchangeable in modern use – as are unstable and metastable. Coleman wrote the book on the subject, so I'll take his word for it. –Joke 21:00, 25 August 2006 (UTC)

Dear Joke 137,

I'm not suggesting that the theory is wrong. I have no disagreement with the theory. I'm saying that the logic (the syntax) of your description (and that of Coleman and de Luccia) is wrong. It's just plain bad english. A false vacuum is not the state of a theory. It may very well be the state of the vacuum but it's not the condition of the theory, itself. English may not be your native language, in which case you will be forgiven, but Coleman's editor should have corrected this.

If I may suggest a correct way to say it: It is possible in a classical field theory for the vacuum to have two stable homogeneous ground states, ...

69.107.143.233 15:38, 7 September 2006 (UTC)D.C. George

English certainly is my native language. Coleman, moreover, is known as one of the clearest, most precise expositors in physics. Perhaps you are confused about the usage of the word "state." A state of a quantum theory is used, roughly, to mean "a vector in the Hilbert space of the quantum field theory." It is one object (a vector or wavefunction) among the collection of objects provided by the theory; it is not meant to describe a particular condition that the theory itself finds itself in. For further details, see quantum state. I see no point in discussing this well-established usage further. –Joke 21:02, 7 November 2006 (UTC)

Syntactically, the first sentence is still wrong. "A false vacuum is a metastable sector of a quantum field theory which appears to be a perturbative vacuum but is unstable to instanton effects which tunnel to a lower energy state." Isn't the metastable sector something predicted or described by the theory? The way it's written is like saying Newton's theory obeys the law of gravity (i.e. the theory falls to earth when dropped), when you really mean to say a rock that falls to earth obeys the law of gravity described by Newton's theory. I'm sure readers will get the drift, but it would make more logical sense if where corrected. -BuzzSkyline 13:07, 11 November 2006 (UTC)

Contents

[edit] More information?

This is a very interesting (to me personally, at least) topic. Any extra information, particularly about the vacuum metastability event, would be much appreciated.

Things like these make me ever regret not choosing theoretical physics as the profession. IgorSF 16:22, 4 January 2007 (UTC)

[edit] Manifold: Time

A Vacuum Metastability Event was used as a plot device in Stephen Baxter's book Manifold: Time

[edit] Speed of Light... and other things

So if a truer vacuum has less "stuff" in it than what may be a false vacuum, is it likely that this would alter the "maximum" speed of light? Whereas things like dark energy/matter in a false vacuum could theoretically slow light down, light traveling through a true vacuum could reach a closer velocity to it's infinite potential, although by partially filling a true vacuum, it makes less of a true vacuum, thus remaining a finite (although much, much faster) speed. With the stakes on light upped, presuming that just-pre-bigbang the singularity was surrounded by true vacuum, matter could also conceivably move faster... right? —Preceding unsigned comment added by 12.146.22.19 (talk) 03:36, 4 February 2008 (UTC)

[edit] I don't get it

So a false vacuum is a lower energy vacuum than our current energy vacuum?

How would that destroy us again? I'm sorry for being stupid. Seriously, it is frustrating for me as well (my stupidity). 68.143.88.2 (talk) 21:03, 24 April 2008 (UTC)

No, the idea is that we are in the false vacuum state, which is at a higher potential (higher energy level) than the 'true' vacuum state. Think of it as ahill with a little depression in the side. If you roll a ball down the hill, it could get stuck in the little depression. That is the false vacuum where we may be. If something came along and knocked the ball over the lip, it could fall all the way to the bottom of the hill, the 'true' vaccuum. The concerns is that a sufficiently heavy particale or energetic collision (like that created in a massive particle accelerator) would be enough to push something over the lip, which would drag the rest of us over. The destruction would be because all of the known constants of nature (speed of light, charge of an electron/proton, mass of elementary particles, etc.) would change, and may not be supportive of existance as we know it (all molecules may spontaneously split apart, as well as all atoms, etc.)
BTW - Don't worry - I don't really get all of it either. Astrobit (talk) 04:31, 25 April 2008 (UTC)
This might help. Imagine a tank of water, but the temperature is below freezing, -10C say. This can happen: the water is supercooled and won't freeze until a "seed" ice crystal forms. At that temperature, ice has a lower free energy than water, so water is a false ground state (= false vacuum) and ice is the true ground state. Eventually the seed crystal forms ("nucleates") and the whole system suddenly freezes, i.e. makes a transition to its true ground state. This "destroys" the water and replaces it with ice. Dark Formal (talk) 21:32, 25 April 2008 (UTC)
Gee, it sure would be nice if the article had some sort of helpful analogies and used clear language in order to make its high-falutin concepts more accessible to non-specialists. If the article is only penetrable to people who would be quite comfortable reading texts in the field anyway, what the fuck is it doing in an encyclopedia? Graft | talk 21:25, 14 May 2008 (UTC)
I agree that the article should be more understandable to non-specialist readers. Is the water analogy helpful? Would you like to see it incorporated in to the article? Do you have any more specific suggestions? Dark Formal (talk) 02:54, 17 May 2008 (UTC)
I like both the hill analogy and the water analogy. I can recognize that idea in the first sentence after hearing it, but the notion is so heavily concealed under jargon that it's practically useless. For example, I shouldn't have to know what an 'instanton' or 'tunneling' between states is in order to appreciate the concept. Also, as others have pointed out above, the notion of a state of a quantum field theory is an unclear concept. These terms are obviously important, but they should be introduced somewhat at leisure, after the reader has gotten some sort of idea of what the hell is going on, rather than attacking them with it at the outset. I don't think an analogy is necessary in the intro; clarity could just be achieved with simpler language. Graft | talk 03:46, 17 May 2008 (UTC)

[edit] article on "True Vacuum"

Since there is an article on "false vacuum", how about an article on "true vacuum"? easonrevant 22:18 EST, 10 May 2008 —Preceding unsigned comment added by 18.244.5.122 (talk) 02:20, 11 May 2008 (UTC)