With all due respect, the Law of Conservation of Matter was shelved just under 100 years ago, along with that for Energy, and a substitution of the Law of Conservation of Matter and Energy replaced them -- based on Einstein's work demonstrating that matter and energy are equivalent and can be converted one to the other. The new law says that the total amount of matter and energy in a closed system, related by c² (remember the OP?), is a constant, though the total of neither component will be.
As for a non-chemical means not the result of man's intervention, I might observe that the Sun shone today, as it has since it was created -- and there is pretty good evidence that the mechanism it uses to keep shining is nuclear fusion. For an even better example, Supernova 1987A in the Large Magellanic Cloud exploded 17 years ago, obviously without our help -- and the first time that we have actually observed a star before it went supernova. The only known mechanisms for a star to explode in that manner invoke thermonuclear physics.
Nitpick for nyjbarnes: "ignoramus" is a coined word, but the method used to coin it suggests that it would have a Latin plural of something like "ignoramides" (3rd declension) -- so the custom is to use the standard English plural-making rule and use "ignoramuses."
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To save you a bunch of reading, yes, He is quite capable of doing that. He's also quite capable of sending all Christians to Hell for believing in Jesus, and saving all atheists, just for kicks. The point is that what we know of His character, what He chooses to be, suggests strongly that neither arbitrary reversals of that sort nor creating a Universe full of false evidence is something that He would actually do. His Peace be with you!