[ethn]

It's not relational. There's several rigorous proofs against Spinoza's relational theory. Namely that of Kant and Einstein:

"even if space is composed of nothing but relations between observers and events, it would be conceptually possible for all observers to agree on their measurements, whereas relativity implies they will disagree" [0]

0: https://en.wikipedia.org/wiki/Relational_space

[ImHereToVote]

Unless one of the observers accelerates for some reason. Now his observation is privileged.

[lgas]

Doesn't relativity mean there's no difference between that observer accelerating in one direction and everything else accelerating in the opposite direction? So wouldn't everyone's observation be equally privileged? I'm asking honestly as am (obviously) not a physicist.

[ImHereToVote]

You would think so, but no. There is something magical about acceleration, specifically how much spacetime you increasingly or decreasingly traverse.