"The theory proposes that..."
A theory explains how something works - a "law" is just a thumb nail description of a theory.
A law is a description of a naturally occurring phenomenon, whereas a theory attempts to explain a law.
a description or explanation of an idea or theory in a story
You're playing with words ... a "law" is just a thumb nail description of a theory.
Cell theory.
It is not an epoch, it is Dali's description of his own art theory.
The gist of this conspriracy theory is that William Shakespeare did not pen all his plays himself. If or even how this can be proved is doubtful.
That is, more or less, the description of the Big Bang.
A description, often mathematical, of how (not why) a process occurs.
proposes that the universe looks the same on large scales to observers.
A law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. It doesn't change. A theory is the explanation but those can and do change.