  This article deals with empty spacetime and the question of its physical
reality. By "empty spacetime" we mean a collection of bare spacetime points,
the remains of ridding spacetime of all matter and fields. We ask whether these
geometric objects--themselves intrinsic to the concept of field--might be
observable through some physical test. By taking quantum-mechanical notions
into account, we challenge the negative conclusion drawn from the
diffeomorphism invariance postulate of general relativity, and we propose new
foundational ideas regarding the possible observation--as well as conceptual
overthrow--of this geometric ether.
