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It might sound a bit naive but,

How is it that conservation of energy is never broken, how is it that we know that always and for sure the energy in our universe is constant and we cannot create a destroyed energy.

I mean is there any mathematical and physical mechanism in the real world that has prevented this from happening or is it just that we have not been able to find any case where energy is being created from nothing that we have led to this conclusion?

Similarly for charges to how is it that in the universe all the charge that is created is conserved.

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    $\begingroup$ Energy conservation follows by Noether's theorem from time translation invariance. Since the Minkowski space is translation invariant, there energy is conserved. However, we do not live in Minkowski space. Energy conservation (at least the common interpretation thereof) is badly broken during inflation. $\endgroup$ – user178876 Jun 19 at 7:20
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As you probably realise, all the energy in the universe was there at the beginning, and according to the 1st Law of Thermodynamics can neither be created nor destroyed. If you are a believer in the Big Crunch - Big Bounce theory of an infinitely recycled universe, this makes perfect sense. One of the things that puzzle me about dark energy is where has this energy been hiding, as it must have been there since the time of the Big Bang. There is a Nobel Prize waiting for someone who can falsify the 1st Law of Thermodynamics, but so far no one has claimed it.

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  • $\begingroup$ The first law of thermodynamics encodes our experience in the labs. It is a big conceptual jump to apply it to the whole universe. $\endgroup$ – GiorgioP Jun 19 at 8:02
  • $\begingroup$ Michael: matter can be created and destroyed. Check out pair production and annihilation. Energy is the thing we can neither create nor destroy. $\endgroup$ – John Duffield Jun 20 at 20:53
  • $\begingroup$ I know all about pair production & annihilation, but it would be wearisome if I had to explain the 1st Law of Thermodynamics every time I mention it. These days we know matter & energy are just two different forms of he same thing; the mass of the electron,for example is 500,000 MeV. Sometimes I consider putting mass/energy instead of mass, but everyone should know what I mean anyway. You can convert mass into energy & energy into mass,but conversion is not the same thing as destruction. Hard luck,there's no Nobel Prize in it for you this time! $\endgroup$ – Michael Walsby Jun 20 at 21:11