What is the correct analogy for the expansion of the universe, according to the text?

Answer

The stretching of spacetime itself between the galaxies.

It is a common misconception that galaxies fly through space away from a center; the text clarifies that the expansion involves the stretching of spacetime itself between the galaxies, analogous to dots on an inflating balloon.

What is the correct analogy for the expansion of the universe, according to the text?
galaxyAstronomerscienceuniversecosmology