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I've watched Lawrence Krauss's lecture and read his book. I think I got what he was saying, and I don't have any problems with that; however, what I can't get is how the laws of physics that makes this phenomenon possible came to be in the first place?

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This question appears to be off-topic because it is about philosophy. –  jinawee Jan 21 at 19:00
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@jinawee nope, there are serious fundamental physicists thinking about such and similar questions these days, such questions are (with the advances in theoretical physics in the course of the last decades) now legitimate in physics too and no longer just philosphy, see for example anna v's answer. –  Dilaton Jan 21 at 21:12
    
@Dilaton I tend to disagree. anna v, in my opinion, changes what is generally understood by the 'laws of physics'. The question seems philosophical to me. (In fact, I am reminded of the philosopher Nozick, who proposed 'self-subsumption', which I understood to mean: laws that generate themselves.) However, there appear to be physicists who aim to make convincing that all mathematically describable worlds exist. (Still suspiciously philosophical; Lewis?) So, who do you have in mind? –  Glen The Udderboat Jan 21 at 21:52
    
@GlenTheUdderboat there are indeed people such as Nima Arkani Hamed (spacetime is doomed, the Amplituhedron) or others working on the so-called ER-EPR correspondance who have discovered that the notions of spacetime, the usual gauge theories of the SM, etc (laws of nature we observe) might emerge as longer than quantum gravity scale limits of smaller scales where the diffeomorphism symmetry (gauge theory of gravity) and the other gauge symmetries can not be discerned. A bit of this is described for example here. –  Dilaton Jan 21 at 22:08
    
@Established theoretical physicists agree that such questions are completely legitimate in fundamental physics and / or even at the cutting edge of theoretical physics, they are in the scope of the Fundamental Physics Price, so the 4 close votes on this question are not justified from a physics point of view. –  Dilaton Jan 21 at 22:11
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closed as off-topic by jinawee, joshphysics, Brandon Enright, Kyle Kanos, John Rennie Jan 22 at 9:24

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1 Answer

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What we call "laws of physics" have an evolutionary path.

It really started with Newton and the falling apple and slowly it evolved into complete mathematical models of experimental observations, called theories. From the observations and the theories conservation laws emerged.

These laws are strictly obeyed within the framework that they have been validated. Take the thermodynamic law "entropy remains the same or increases in closed systems" . The region of validity of the law was transformed when the atomic nature of matter became understood, and statistical mechanics became the underlying framework. There, from an absolute law it became an estimate of probability outcomes, which to all intents and purposes recreates the law for macroscopic systems.

If the universe could emerge from nothing, what about physical laws?

As our observations and experiments advance, new mathematical frameworks appear which transmute the laws of the overlying frameworks : conservation of energy became the relativistic four vector energy which blended mass in the mixture. Conservation of relativistically defined energy and momentum also became fuzzy instead of absolute due to the Heisenberg uncertainty principle of Quantum Mechanics .

So when we come to cosmology where there exist theoretical models of solutions of General Relativity it is not surprising that apparent inconsistencies with conservation laws developed for different frameworks.

At the moment there does not exist a theory of everything which quantizes gravity and includes the other three forces, weak, strong, electromagnetic that has been validated through all relevant observations, even though string theory offers such possibilities. It is therefore premature to be definitive of how the known conservation laws validated by our laboratory experiments will evolve in a cosmological setting. Something and nothing have to be mathematically defined within the appropriate theoretical models.

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I didn't get how a theory of everything could answer this question? –  MAyman Jan 21 at 21:27
    
Awesome answer btw. –  MAyman Jan 21 at 21:28
    
I think this answer misses the point. Although 'the laws of physics as currently understood' may evolve, the question seems to be focussed (my opinion) on 'the laws of physics simpliciter'. The questions assumes that there are (or is a) fundamental law(s), or a law-generating principle. 'Where did that come from?' seems to be the question. –  Glen The Udderboat Jan 21 at 21:28
    
To take this into the ridiculous: According to this answer there were no 'laws of physics', say, 5 billion years ago. (I'm sure some philosophers might agree, ... but physicists?) –  Glen The Udderboat Jan 21 at 21:38
    
@GlenTheUdderboat my answer says that laws are conditional on the physical and mathematical framework under examination, at least this is what the history of physics says. The question assumes that "creation out of nothing" is a fact and then wonders about the consistency with our known laws. I am explaining that our known laws evolve according to our observations and theories and the theories are consistent at their boundaries of application so there is no contradiction since "nothing" is not defined without a TOE. –  anna v Jan 22 at 5:28
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