One informal way to think of homomorphisms in math is that they are maps that do not “create information out of thin air”. Isomorphisms further do not destroy information. The terminal object (e.g. the trivial group, the singleton topological space, or the trivial vector space) is the “highest-entropy state”, where all distinctions disappear and reaching it is heat death.

• Take, for instance the group homomorphism \(\phi:\mathbb{Z}^+\to\mathbb{Z}_{4}^+\). Before \(\phi\) was applied, “1” and “5” were distinguished: 2 + 3 = 5 was correct, but 2 + 3 = 1 was wrong. Upon applying this homomorphism, this information disappears — however, no new information has been created, that is: no true indinstinctions (equalities) have become false.
• Similarly in topology, “indistinction” is “arbitrary closeness”. Wiggle-room (aka “open sets”) is information, it cannot be created from nothing. If a set or sequence goes arbitrarily close to a point, it will always be arbitrarily close to that point after any continuous transformations.
• There is no information-theoretical formalization of “indistinction” on these structures, because this notion is more general than information theory. In the category of measurable spaces, two points in the sample space are indistinct if they are not distinguished by any measurable set — and measurable functions are not allowed to create measurable sets out of nothing.