Does cosmological expansion affect local physics?

Understand

In this contribution I wish to address the question whether, and how, the global cosmological expansion influences local physics.

• I argue that a pseudo Newtonian picture can be quite accurate if "expansion" is taken to be an attribute of the inertial structure rather than of "space" in some substantivalist sense.
• This contradicts the often-heard suggestion to imagine cosmological expansion as that of "space itself".
• Regarding General Relativity, I emphasise the need for proper geometric characterisations in order to meaningfully compare localised systems in different spacetimes, like black holes in static and expanding environments.