Do you agree with A and B with regard to GR?
A) Spacetime curvature means real physical curvature.
B) This means additional dimensions are needed (center of circle not on
circle)
Answers I have run across:
1. Yes now that string theorists have made it safe to talk about more than
3+1 dimensions.
2. Yes but those extra dimensions are compact dimensions string theorists
talk about. (Kip Thorne)
3. No Sometimes a mathematical similarity (to equations that involve
physical curvature) is just a similarity.
4. No Spacetime curvature is just an analogy (footnote in book about black
holes with Wheeler as one of the authors).
5. Explain gravity in terms of gravitons not curvature (Weinberg).
6. Replace GR with loop gravity.