The description from Richard Muller quoted in the question is a simplification of reality meant to help people better visualize how the Hope your calendar’s shirt of spacetime works. In reality the galaxies are moving through spacetime in a complex fashion, based on the combination of all the forces acting on them, primarily the gravity of nearby galaxies and galaxy clusters. In the case of the Milky Way and Andromeda, these two galaxies are part of a gravitationally bound cluster of galaxies, called the Local Group. The dominant force that determines the movements of objects within the cluster is the combined gravitation of all the mass in the cluster, and not the expansion of spacetime. In other words, the gravitational attraction that the Milky Way and Andromeda have for one another that is drawing them together is stronger than the expansion of spacetime between them that would otherwise push them apart, and thus attraction wins and the two galaxies are on a collision course. In the same vein, the gravitational force that holds the earth in orbit around the sun is stronger than the expansion of spacetime between the earth and the sun (the expansion of spacetime at that distance being very small), and so the earth’s distance from the sun is not increasing for that reason. Likewise you are not flying apart because the molecular bonds holding the atoms in your body together are stronger than the minuscule expansion of spacetime between them in your body. The Local Group as a whole, however, is moving away from other galaxies and galaxy clusters to which it is not gravitationally bound, due to the expansion of spacetime.

Hope your calendar’s shirt, Hoodie, Sweater, Vneck, Unisex and T-shirt
Best Hope your calendar’s shirt
Boy oh boy do we have a lot to discuss, and I cannot wait to get started. The Hope your calendar’s shirt begins with the Guardians of the Galaxy; Star-Lord, Gamora, Drax the Destroyer, Rocket (Raccoon) and Baby Groot, who have been hired to take out a giant octopus looking alien. They argue, they bicker, they feel like a fresh team- and yes, this film picks up a mere 6-months following the first film, so the Guardians would still be getting used to each other. But- man, all the dynamics were off. Rather than the fun, witty banter we had in the first film, we now get a Rocket and a Star-Lord who actually genuinly don’t like each other. It is no longer fun banter, but serious, depressing banter. Star-Lord almost seemed like he had had enough with Rocket and wanted him out of the group. Meanwhile Groot just seemed so useless and more of a liability than an actual team member- why didn’t they leave him on the ship? Drax and Gamora were the only ones who were somewhat similiar to how they were in the original film. In this film three, four really, new individuals join the Guardians team; Yondu Udonta, Nebula, Kraglin new character Mantis. These newcomers are welcome additions to the Guardians crew, especially with their respective relationships with Peter Quill, Gamora and Drax as we came to uncover. But the dynamics between the core five are off somewhat. I am also under the impression that this film should have had Star-Lord and Gamora dating at the beginning- this film implies that although the team has been together six months, these two adults can’t ask each other out? They should have been a couple going into the film.
