Describe the conditions under which scientific laws and theories can be changed?

Not so much changed, but simply modified to the current consensus of the scientific community. Dark Matter Energy is somehow composing 75% of the mass of this Universe. Only 25% of the mass is composed of stars, planets, black holes, etc. The theory is that the Universe will continue expanding forever pulling everything apart by this unseen and undetectable mass surrounding us out there. Even after the last sun burns out there will be an absolute light zero and space temperature zero(-454F) throughout the entire Universe. Atoms will even be ripped apart by this Universal Black Wasteland, leaving a vapor trail of molecules waiting for the next beginning. That may be what will set up the beginnings for the next Universe.