How do we know that constants are constant?

[ClaysGhost]

Im no scientist and I don't quite follow all the developments in the scientific world, so could somebody explain, is there such research undergoing and can it be called "science" or is it just pure bullcrap?

I don't remember the details but there was a team in Australia doing work with line ratios from quasars. Variations in the fine structure constant would cause detectable effects in quasar spectra. This seems to be of that principle, although it's mainly advertising; if you want something more informative you'll have to look the authors (or the topic) up on ADS or something.

[Admiral Valdemar]

Is there any reason to believe that virtual particle pair generation is analogous to the Big Bang?

It's something thrown around to possibly explain how the universe could have always existed, though I'm more a fan of brane theory and the creation of new branes via the interaction of others in the bulk hyperspace. Plenty of ideas, just little solid evidence. Even with brane theory, what made the branes crops up then, just as it would with God if the deity explained how our universe came to be.

What annoys me is the way creationists think that the question of existence can be solved by simply moving it to a higher plane. It's like their idea of a "meaning of life", which is to serve God. I like to ask "OK, what's the meaning of God's life?" It's funny how I never get an answer.

They never expect to have to speak for the almighty, the way he works is mysterious and so always open to interpretation, which suits them if something fucks up their previous theory of how events should unfold. He has a plan, but don't ask for a carbon copy. Celestial receptionists suck.

[drachefly]

Actually, chemistry is fairly stable as it's mostly based off of the counting properties of electrons under the Pauli Exclusion Principle. Unless you changed the functional form of the potential away from being inverse square; that would screw things up.

Um, drachefly, chemistry isn't all about quantum numbers of electrons.

Mostly. See that?

Taking it from another angle, perturbation theory is important in predicting results in quantum electrodynamics, and physical results in the theory can be expressed as a power series in the fine-structure constant. Therefore, changing the fine-structure constant changes the importance of each term in the final answer.

And every term after the first two is nearly irrelevant to chemistry. You get the way the fine structure constant affects the masses of the particles, and the way it scales the electrostatic forces (both of which merely rescale scale the system); then you get the spin-orbit coupling. That's alpha to the fourth, I believe, and already the effects are small enough that we can see that any higher powers of alpha are going to produce only changes that are severely suppressed.
If spin-orbit is alpha squared, then even better: all the effects that shape most chemicals are of order alpha-squared. Sure, you might lose xenon hexafluoride or something like that, but who gives a shit about that?

As Kuroneko and I said, it's the nuclear stuff that's the main problem: it's relativistic: so those changes in mass which merely rescaled chemistry completely change nuclear physics.

[Wyrm]

Ya, drachefly, I did see Kuroneko's response. Nuclear physics goes kaput long before chemistry.

[drachefly]

I was just saying why, and integrating it with what you said. You were correct, after all!

[Wyrm]

I was just saying why, and integrating it with what you said. You were correct, after all!

I'm technically correct. But since nuclear physics goes kaput before chemistry, if the constants changed enough for chemistry to have a substantially different character from what we know it, then we are unlikely to have elements of sufficient variety to really have much chemistry anyway. (That's how I understand Kuroneko's comment on the matter.)