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Stars Could Shine In Many Universes
A commonplace of cosmologists who argue the anthropic principle is the assumption that if any or a few of the constants of nature took on an even slightly different value, life could not have evolved — perhaps even stars and galaxies would not form. Science News reports on a new calculation showing that, to the contrary, star formation could happen in up to one-quarter of universes with different values of three important constants. "In fact, all universes can support the existence of stars, provided that the definition of star is interpreted broadly," said the researcher, Fred Adams. "...calculations suggest that, contrary to some previous claims, stars are not only common in our cosmos but are also ablaze in myriad other universes, where the laws of physics may be drastically different... Had Adams found that the range of parameters that allowed for stars was very small, that would have suggested that the laws of physics in our universe have been 'fine-tuned' to allow for star formation... Instead, Adams' study shows that our universe doesn't seem particularly special in that regard."
> the universe is actually a rather robust structure.
.. at least w/r/t star formation.
slightly OT, the thing i really dislike about Intelligent Design arguments is that they're essentially a way of just giving up trying to explain things. they equate to "it's irreducibly complex, therefore we can learn no more", or "the chances approach zero, therefore we can learn no more". but science constantly discovers new things, throws old things out, etc. an essence of science is *not* deciding you've learned as much as you can or that you've arrived at the ultimate explanation.
As already pointed out by another reply, this only applies specifically to star formation, which was just one piece that has to be in place for life to work out. Even if this particular one has a 25% chance of happening, there are still a lot of others. Like existing long enough to make heavy elements, or having the right ratio between gravity and electromagnetic forces.
Not a typewriter
How did this tired chestnut become a meme among supposedly smart people? "God did it" refers to agency, just like "time and chance" refers to agency. The "how" is a completely different matter. As a child, I remember asking my father, "How did you do that, Dad"? If anything, it whetted my curiosity to know more.
Whatever position one holds on the "irreducible complexity" argument, the argument is not "therefore we can learn no more." Rather, the argument is "the agency of time, chance, and unguided selection couldn't be the cause of such-and-such an object."
There are several kinds of low probability events. A lottery has a low probability of any one ticket winning, but a very high probability that somebody will win because there are so many tickets. For universes to work like that, there have to be enough universes that as you put it, "it's got to happen to someone". Science hasn't "uncovered" (again, your word) this situation, unless they have proved that parallel universes definitely exist, there are definitely enough of them for the low probabilities to sum, and the meta-laws of these universes allow summing the low probabilities.
Uncovered would mean:
1. Scientist observes parallel universes.
2. Scientist counts enough of them to prove the low odds can sum to likely odds, or finds a good proof there are enough. A good proof has to be more rigorous than is usual in physics, because our universe's physics may not be the ruleset in any of these others. Probably this means the proof has to meet formal mathematical standards.
3. Scientist has to have a Theory of Everything for our universe.
4. Scientist has to derive similar theories for the other universes and a meta-theory that combines them.
5. Scientist then has to show that the meta-ToE allows low probability events to sum.
I'm pretty sure none of those steps have happened. If I'm wrong, I'd like to predict what discoveries get awarded the next ten Nobel prizes in physics, and probably a Fields medal or two.
Who is John Cabal?
This hypothesis, if true...
The Standard Model has 19 free parameters (not including G) and even more if you include the new neutrino mixing results. This guy varies TWO of them plus G and then claims that 25% of possible universes would form stars? I remain completely unconvinced. While the strength of gravity, EM and the strong interactions may be important for stars the other parameters control some other vaguely important things like whether there is any matter in the universe.
In addition these parameters also have major effects directly on the functioning of stars. For example if the electron mass were larger the orbit of the electron in the atom shrinks and fusion becomes a lot easier. One would presume that this would greatly affect star formation. In addition there are other effects caused by varying the parameters: tweaking with these may well change the type of matter in the universe such as less hydrogen and more helium etc. He does at one point mention this and then states that he would not expect it to vary much from our universe without giving a reference. To me this seems completely non-obvious but I'm not a cosmologist so perhaps it is obvious to them?
So as I said I remain totally unconvinced that this paper really shows anything meaningful at all.
As I said above, I think the multiverse theories are a pantload of stink.
The interesting thing about a way of describing the universe is that it doesn't have to be true to be userful, provided it produces useful results.
Think for a moment of Copernicus.
His model wasn't accurate at all, not even slightly, it was nowhere near as useful in real terms then the Ptolemaic model, but it allowed the universe to be viewed in a different way, eventually leading to our current, vastly more accurate description.
Ours too may be wrong, but you need ways of describing reality which produce useful results. They don't have to be 'real' to be useful.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
You watched NOVA and some SA articles, appear to have utterly failed to comprehend what QM is, but don't worry, /. is the perfect place to make believe that a few dozen TV shows and four or five page articles makes you an expert.
QM is in fact one of the most successful scientific theories in history, predicting and explaining a very large number of phenomena. It's responsible for a goodly portion of the technology you're using right now to broadcast to the world the extent of your idiocy.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Yeah, and "atom" means "indivisible." Therefore, "atom smasher" is an oxymoron, and particle physics is just the product of deranged imagination.
That's how you know you have a really powerful theory: when it lets you meaningfully ask more questions. When Newton figured out how gravity worked we could suddenly ask all sorts of questions about planets, stars, solar systems, and other interesting bits of the universe. Quantum mechanics does the same thing for our ability to investigate the very small, and parts of reality itself.
Which part of quantum mechanics are you referring to, that predicts other universes? Do you mean certain interpretations of Feynman's sum over paths method? That's not really a prediction, just a convenient what-if explanation for an interesting trick Feynman figured out for calculating probability waves. It's very interesting, but not a requirement for QM to work.
I BELIEVE that Jesus Christ was who he said he was and is, namely God. He demonstrated this by the unique powers over the forces of nature and more importantly over death. However, science cannot observe or demonstrate this and therefore it belongs into the realm of faith, in this case religious faith. Of course, everyone who has faith, believes it to be the truth. Faith can turn out to be true in the end, but it is still faith and will always remain faith, never science.
Just wondering why you chose Christianity over, say, Islam or Buddhism or Shamanism. Feel free to ignore my question if you want, but it always interests me to know why people choose a particular religion (which almost always originated or was historically propagated within their cultural group). Do you apply the concepts of rigorous hypothesis testing to Biblical claims, or do you just accept everything the Bible says (and do you read the original Greek and Aramaic, and why do you discount the apocryphal and gnostic works yet accept the concept of the Trinity, etc.)?