If energy could<span> be created or </span>destroyed<span>, all of our ideas of how the world works ... Historically, of course </span>not<span> all the forms of energy were known to begin with. ... too messy or complicated to make sense, we </span>would have<span> had to give up the law. ... </span>can<span> be converted into rest </span>mass<span> and back again (particle physicists </span>do<span> this </span><span>every )</span>
The sun creates nuclear energy in it's core and as a byproduct heat is created. It gives this off in the form of heat and radiation.
