Explore the fundamentals of Spectral Graph Theory in this graduate-level lecture from Carnegie Mellon University's "CS Theory Toolkit" course. Delve into the basic setup and the quadratic form associated with undirected graphs. Learn about functions, absolute key concepts, and examine practical examples. This 22-minute video, part of a semester-long series on math and CS fundamentals for theoretical computer science research, is taught by Ryan O'Donnell and draws from Daniel Spielman's book "Spectral and Algebraic Graph Theory". Gain valuable insights into this essential topic for advanced computer science studies.