Special Lecture “A Times in Archaeology”

Special Section: Contemporary Archaeology in Yucatan

This issue’s Special Section reflects the theoretical perspectives and methodologies in use within the field of Maya archaeology as practiced currently in the northern lowlands of Yucatan, Mexico. These articles contribute to a conversation that began with the “Special Section: Recent Chronological Research in Northern Yucatan” in Ancient Mesoamerica vol. 9, no. 1 (1998). In a region where chro...

Special Lecture

Special Lecture - The Octionions

Forming real vector spaces, we have the linear maps, which preserve the vector space structure L(n; R) = { M : R → R ∣∣M(a~x+ b~y) = aM(~x) + bM(~y) } (1) This is a monoid, not a group, as inverses may not exist. The first group is the general linear group, which preserve dimensionality GL(n; R) = { M ∈ L(n) ∣∣M is invertible } . (2) Further, we have the area preserving maps SL(n; R) = { M ∈ L(...

Lecture notes on Stopping Times

Markov chains are awesome and can solve some important computational problems. A classic example is computing the volume of a convex body, where Markov chains and random sampling provide the only known polynomial time algorithm. Arguably the most important question about a Markov chain is how long to run it until it converges to its stationary distribution. Generally, a chain is run for some fi...

Very Special Relativity in Curved Space-Times

The generalization of Cohen and Glashow’s Very Special Relativity to curved space-times is considered. Gauging the SIM(2) symmetry does not, in general, provide the coupling to the gravitational background. However, locally SIM(2) invariant Lagrangians can always be constructed. For space-times with SIM(2) holonomy, they describe chiral fermions propagating freely as massive particles.