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The standard model has a number of free parameters [1] but the results of calculations are pretty sensitive to them, and this is what predicted (not just explai
by andreareina 3y ago
The standard model has a number of free parameters [1] but the results of calculations are pretty sensitive to them, and this is what predicted (not just explained post-hoc) the Higgs. It's not incorrect to say there's curve fitting involved, but it severely understates the magnitude of the achievement that is the standard model, and its success in explaining everything that underpins everyday life[2], as well as most things beyond that regime[3]
[1] https://en.m.wikipedia.org/wiki/Standard_Model#Construction_of_the_Standard_Model_Lagrangian https://en.m.wikipedia.org/wiki/Standard_Model#Construction_...
[2] https://www.preposterousuniverse.com/blog/2010/09/23/the-laws-underlying-the-physics-of-everyday-life-are-completely-understood/ https://www.preposterousuniverse.com/blog/2010/09/23/the-law...
[3] https://physics.stackexchange.com/questions/128374/evidence-of-why-the-standard-model-is-a-successful-theory-of-particle-physics#:~:text=Perhaps%20the%20biggest%20success%20of,prediction%20of%20the%20Higgs%20Boson https://physics.stackexchange.com/questions/128374/evidence-....
- zmgsabst 3y agoThe standard model doesn’t explain GPS satellites.
- jfengel 3y agoBut relativity explains GPS. And the two theories together explain practically everything to insane levels of precision. The only time they go wrong is when they both operate at once, in a narrow range around black holes or the very earliest universe.
- lilgreenland 3y agoThey also go wrong with large scale phenomena like inflation, dark matter, and dark energy.
- azalemeth 3y agoThere's also the problem of fine tuning -- why is the fine structure constant roughly 1/137? If it were different from its current value by a tiny amount, the universe as we know it wouldn't exist. Is the anthropocentric principal the only explanation we have -- it has the value it has because it produces a universe in which we're able to observe it? And I guess less formally there's also the problem of complexity: condensed matter physics exists because trying to solve the standard model for a solid directly is both incredibly infeasible (think "cost of flipping bits in the calculation far extends that of all matter in the observable universe") and fails to capture the emergent phenomena in a natural way.
- robertlagrant 3y agoThe other theory is there are infinite universes somehow being created all the time by every choice. Which to my mind isn't very Occam's Razor-ish. But it does exist as a theory.
- mr_mitm 3y agoYou mean the Many-Worlds interpretation? That's not every choice, but every quantum measurement. And it's not necessarily an infinite number. And it's not a theory, but an interpretation. And it's actually very Occam's Razor-ish (at least that's what proponents claim), because it needs less postulates than the standard Copenhagen interpretation. The many worlds are a consequence, not a postulate.
- naasking 3y agoIt's the multiverse theory, typically discussed under the framework of string theory.
- oneshtein 3y agoIMHO, "Inflation" is false theory, because it doesn't obey law of conservation of energy. If no inflation, then no Big Bang, so our Visible Universe is much older. If our Universe is much older, then life evolved multiple times already. Red stars are shallow gravity wells, so they are primary target of an expansive civilization, because it easy to enter/exit them, so they are colonized first and their light is captured fully.
- Thiez 3y agoCool story. Now explain why almost everything we see is moving away from us, where fresh hydrogen for stars comes from in an ancient universe, where the cosmic background radiation comes from, why the distant universe appears 'younger'... Note that the 'laws' of physics are no better than normal scientific theories, scientists just had more hubris back then.
- robertlagrant 3y agoI don't even know where "fresh" hydrogen comes from for new stars in our current universe. Why would it be different for an older one?
- ninkendo 3y agoWe have a good idea where it comes from: It was created in the big bang, and as stars form (and explode, or form neutron stars and collide) they turn it into heavier elements. Over time there is less hydrogen, which is why the universe can’t be infinitely old. Since it’s only ~13.7B years old, the amount of hydrogen we see makes sense with our models. It’s a much much bigger problem if the universe significantly older than we think it is… if we were to believe the Wikipedia article on this[0], we’d only expect stars to exist at all for about 100 trillion years, but given that the distribution of hydrogen availability is likely to follow an inverse exponential decay curve of some sort, we’d probably see much lower amounts of hydrogen much earlier than that. [0] https://en.wikipedia.org/wiki/Future_of_an_expanding_universe#The_Stelliferous_Era https://en.wikipedia.org/wiki/Future_of_an_expanding_univers...
- deleted 3y ago[deleted]
- jiggawatts 3y agoGeneral Relativity doesn’t end just above the atmosphere and quantum mechanics ought to apply to everything, not just experiments. The current microscopic models don’t even attempt to explain how a molecule of water is lighter than the oxygen and two hydrogen atoms that went into making it. Oh sure, we can wave our hands at it and invoke the mass-energy relation from GR, but this doesn’t “pop out” of the Standard Model in any sense. This isn’t some exotic phenomena only found in deep space! We have a long way to go before we can par ourselves on the back and claim to truly understand what’s going on.
- consilient 3y ago> General Relativity doesn’t end just above the atmosphere and quantum mechanics ought to apply to everything, not just experiments. No one disagrees, but if it were that easy to just jump straight to the final theory we would have done it long ago. For now, effective theories are all we've got. > Oh sure, we can wave our hands at it and invoke the mass-energy relation from GR, but this doesn’t “pop out” of the Standard Model in any sense. Yes, it does. You don't need GR for mass-energy equivalence, just special relativity. And the Standard Model is fully special-relativistic.
- vaidhy 3y agoNothing says mass-energy equivalence cannot be applied to small particles. We have a good explanation of a very large set of physical phenomena. Yes, there are always things that are unknown and more you know, the more there is to know at the edges. No one is claiming to "truly" understand anything and your cynicism is misplaced.
- houston_Euler 3y agoCan you point to some evidence for the claim that "a molecule of water is lighter than the oxygen and two hydrogen atoms that went into making it?" I could understand the atoms sharing electrons, but just want to make sure I'm understanding you correctly, because you said it's unexplained.
- jdkee 3y ago
- jjtheblunt 3y agoIf it explains everything then why are experiments still ongoing? What is left to explain?
- consilient 3y ago"everything that underpins everyday life" is not everything. A more precise way to put it would be that we understand physics at the energy scales we've been able to probe.
- exmadscientist 3y agoTo oversimplify: the Standard Model is pretty great when you've got two particles. As soon as there's three, it's too hard to calculate most things people are interested in. Oh, or gravity. Gravity's a problem too.
- 6nf 3y ago'everything that underpins daily life' does not include everything in the universe, for example it excludes dark matter and dark energy, neither of which matter at planetary scales like here on earth.