Locally Symmetric Spaces are the basis of the Langlands program—a set of ambitious and interconnected conjectures connecting representation theory to number theory, firstly proposed in 1967 by Robert Langlands.
These spaces have become a crossroads for many different strands of mathematical thought, and there are two topics recently an IAS 2017-2018 special program placed particular focus on. These are two of these areas:
To quote from the words of Akshay Venkatesh:
Analysis on locally symmetric spaces The motivation to study this comes both from the Langlands program, and from analytic number theory. The techniques are drawn from representation theory and analysis on manifolds, among others.
Topology of locally symmetric spaces Here the subject is guided by Langland conjecture that relates the cohomology of locally symmetric spaces to algebraic varieties. Understanding subtler features of this conjecture was a central theme of the program.
Langlands program tells a relationship between the topology of locally symmetric spaces and the theory of motive. But this is still too far from the real world (not direct physical implications.)
My questions are that have these ideas made connections to physics or physical sciences so far? What are the examples?
It looks that the crystal and lattice structure underly some algebraic structure.