Hello! I’m Saad Khalid, a 6th year Ph.D. student at The Ohio State University studying theoretical quantum physics, of the many-body variety. For the past several years I have also been working on various projects involving AI, ranging from forecasting the weather to correcting pulse-oxymeter readings; you can read more about them in the Projects section!
I’m often asked how physics is related to machine learning. This is an active area of research, but already there are many clear technical similarities between the two fields. Applying gradient-descent to the parameters of a high dimensional function in order to minimize a loss function on some dataset (a process which forms the backbone of training neural networks) is exactly what physicists do when theyre trying to find a variational wavefunction that best describes some quantum system. Another similarity can be seen in diffusion AI such as Stable Diffusion: the principles underlying their generative capabilities are equivalent to the physics underlying thermodynamics[1].
However, I believe there’s an even more fundamental relationship between the two fields. In many-body physics, one finds that if you put a large number of mundane seeming particles together, they end up organizing themselves in a variety of surprising and fantastic ways, leading to everything that exists (solids, liquids, magnets, the sun!). Similarly, if one takes neurons (each individually behaving quite simply) and connects many of them together, you end up with a system that is able to understand everything that we know (ie the brain and, if things keep progressing as they are, perhaps neural networks). Changing the environment the particles sit in (such as changing the temperature or pressure) changes their collective behavior. I’m very interested in the changes we can make to neural networks in order to change their collective behavior and strengthen their ability to learn (for example, increasing neuroplasticity, creativity, and neuron interconnectedness)!
Education
Ph.D. Physics at The Ohio State University, 2018-present
M.Sc. Physics at The Ohio State University, 2018-2021
B.Sc. Physics & B.Sc. Mathematics at Rhodes College (2014-2018)