This thesis presents my work on exploring the use of large mass Stern-Gerlach interferometry for measuring both classical and quantum mechanical aspects of gravity. Chapter 1 serves as an introduction of the background physics necessary to
understand this thesis. Part I (Chapters 2 and 3) is concerned with the underlying
quantum mechanical mechanism behind a previously proposed experiment aimed
at evidencing the quantum nature of gravity by witnessing gravitationally mediated
entanglement. This includes determining the assumptions which must hold for a
conclusion to be drawn from a positive result of the experiment and providing a
clear and intuitive understanding behind what can and what can not be proved by
such an experiment. Finally, this section presents the work done to explore further
how entanglement forms in gravitationally interacting quantum systems. Part II of
this thesis (Chapters4 and 5) discusses how a large mass interferometer will couple
to the space-time metric for use as a detector. This includes considering the basic
design of such a device, how different components of the space-time metric can
be identified individually and an initial exploration of the final sensitivity of such
a device given realistic noise parameters. Part III (Chapter 6) of this thesis looks
at how such devices may be implemented experimentally, building off previous designs to create a large mass, large spatial superpositions with sufficient coherence
to enable their use for interferometry. This is done to specifically design the interferometer around some issues and limitations with large mass interferometry using
the Stern-Gerlach effect which have not been considered elsewhere.