Modeling how gases, liquids, and solids transition into each other is an important area in physics. However, not all materials fit neatly into these three categories. Glass is an example of a material that resembles a solid but has bonding properties similar to a liquid. To study glass, physicists have developed the spin-glass model, a variation of the Ising model. It turns out this model has close connections to satisfiability problems in theoretical computer science, which includes logic puzzles like SuDoKu, and error correcting codes in coding and information theory.
While people like to neatly categorize transitions in life, they sometimes do not fit neatly into categories. A day before a child’s fifth birthday, is the child mentally closer to five or four?
Recently, people have started to treat me like a senior graduate student. New students have asked me for advice. Most of the graduate students senior to me have graduated and started post docs or faculty positions. I have a plan for a thesis topic. At the same time, I have yet to officially advance to candidacy and have yet to receive serious feedback on my new research direction from faculty members outside my advisor pool.
Some transitions are hard to characterize, but others are quite easy. In a couple weeks, Andre Agassi will have played his final US Open match and begin retirement. Then again, he looks a little young to be joining the AARP.