A. Questions for Submission

6.1 General Relativity

1. What are the differences between special and general relativity?
2. What is the puzzle in Newtonian gravity about inertial and gravitational mass? Do you think this is a problem?
3. How does General Relativity avoid the puzzle above?

6.2 Einstein's Field Equations

1. State and explain the meaning of Einstein's field equation.
2. Draw a spacetime diagram of four observers at rest in Minkowski spacetime. Draw a hypersurface of simultaneity for these observers, and use it to argue that this spacetime slice is flat (i.e. has zero curvature). What is the curvature of all the other slices?
3. What does Einstein's field equation say about the stress-energy in Minkowski spacetime? Is this the only spacetime with this property?

6.3 Seven Steps

State one of the 'top 10 tips' from Bryan's 7 Steps to a Better Philosophy Paper.

B. Optional Further Discussion (No Submission)

• The depiction of a "funnel" such as the one below is one of the most common portrayals of gravity in general relativity, but also one of the most misleading. What does the image actually depict? How might someone easily misunderstand the image?
• One of Einstein's most famous predictions was about the bending of light. How was this prediction confirmed? Is it possible to interpret this result in the context of Newtonian gravity?