A 2015 UAF CS 463 lecture page by Dr. Lawlor explains AES math: bytes are GF(28) elements, addition is XOR, and products reduce modulo x8+x4+x3+x+1, matching FIPS 197. It suggests lookup tables and never mentions side channels. NIST says its suggested implementations give no protection against implementation attacks, and Bernstein's 2005 paper recovered a full AES key from timings of a test server he built to minimize noise.
https://www.cs.uaf.edu/2015/spring/cs463/lecture/03_23_AES.html