Introduction to Hilbert Spaces: An Adventure In Infinite Dimensions

Looking for some serious entertainment with an intellectual bent on Tuesday nights this fall? Professor Michael Miller has got you covered in multiple dimensions.

Dr. Miller has now listed his mathematics offering for Fall 2025 at UCLA Extension. It’s Introduction to Hilbert Spaces: An Adventure In Infinite Dimensions (MATH 900). As always, it will be presented in lectures on Tuesday nights from 7:00 PM to 10:00 PM with a short break in the middle. The class runs from September 23 – December 9 and is a screaming deal at just $450.00. 

As many know, Dr. Miller does a superb job presenting advanced and abstract mathematics to the point that most students who take one or two classes return for decades. If you’re a fan of math and physics and have wanted to delve beneath the surface, this is an excellent opportunity to not only begin, but to meet lots of others who share your interests. For newcomers interested in taking a peek, I’ve written up a short introduction to his teaching style with some hints and tips based on my 18 years of taking coursework with him in his 52 year teaching career. There’s definitely a reason dozens of us keep showing up.

Here’s the description in the course catalog: 

This course is designed for scientists, engineers, mathematics teachers, and devotees of mathematical reasoning who wish to gain a better understanding of a critical mathematical discipline with applications to fields as diverse as quantum physics and psychology.
A Hilbert space is a vector space that is endowed with an inner product for which the corresponding metric is complete (i.e., every Cauchy sequence converges). Examples include finite-dimensional Euclidean spaces; the space l2 of all infinite sequences (a1, a2, a3, …) of complex numbers, the sum of whose squared moduli converges; and the space L2 of all square-summable functions on an interval. This introductory, yet rigorous, treatment focuses initially on the structure (orthogonality, orthonormal bases, linear operators, Bessel’s inequality, etc.) of general Hilbert spaces, with the latter part of the course devoted to interpreting these constructs in the context of Legendre polynomials, Fourier series, Sobolev spaces, and other prominent mathematical structures.

The listed prerequisites for the course are calculus and linear algebra, though Dr. Miller generally does an excellent job of bringing up students without a huge machinery of mathematics background or sophistication up to speed to appreciate the material. Whatever you do, don’t let the technical nature of the description deter you from jumping into abstract mathematics with both feet.

Bibliography

The UCLA Bookstore currently doesn’t have a suggested textbook for the course listed. Dr. Miller doesn’t require a textbook, but will often suggest one in addition to the incredibly comprehensive notes he provides in his lectures for understanding the subject. For the curious and the less-experienced or budding mathematicians out there, his lecture notes are clearer and imminently more understandable than any book you’re likely to find on the subject.

For those curious in exploring the space, I’ve put together a short bibliography of some of the more common textbooks covering the undergraduate and graduate studies within the area. Dr. Miller is sure to choose one at the level of an advanced undergraduate (junior or senior level). 

Quantum mechanics anyone? Dozens have been disappointed by UCLA’s administration ineptly standing in the way of Dr. Mike Miller being able to offer his perennial Winter UCLA math class (Ring Theory this quarter), so a few friends and I are putting our informal math and physics group back together.

We’re mounting a study group on quantum mechanics based on Peter Woit‘s Introduction to Quantum Mechanics course from 2022. We’ll be using his textbook Quantum Theory, Groups and Representations:An Introduction (free, downloadable .pdf) and his lectures from YouTube.

Shortly, we’ll arrange a schedule and some zoom video calls to discuss the material. If you’d like to join us, send me your email or leave a comment so we can arrange meetings (likely via Zoom or similar video conferencing).

Our goal is to be informal, have some fun, but learn something along the way. The suggested mathematical background is some multi-variable calculus and linear algebra. Many of us already have some background in Lie groups, algebras, and representation theory and can hopefully provide some help for those who are interested in expanding their math and physics backgrounds.

Everyone is welcome! 

Yellow cover of Quantum Theory, Groups and Representations featuring some conic sections in the background

I just couldn’t wait for a physical copy of The First Astronomers: How Indigenous Elders Read the Stars by Duane Hamacher, Ghillar Michael Anderson, Ron Day, Segar Passi, Alo Tapim, David Bosun and John Barsa (Allen & Unwin, 2022) to arrive in the US, so I immediately downloaded a copy of the e-book version.

@AllenAndUnwin @AboriginalAstro

Bookmarked Lecture Notes by Arun DebrayArun Debray (web.ma.utexas.edu)
I LATEXed up lecture notes for many of the classes I have taken; feel free to read through them or use them to review. If you find a mistake or typo, please let me know. If you want to look over the .tex source for any of these notes, please send me an email.
A great set of LaTeXed notes from a variety of coursework.

via Rama Kunapuli.

Read I re-read Surely You’re Joking, Mr. Feynman! by Jason McIntoshJason McIntosh (Fogknife)
Revisited this collection of Richard Feynman's eclectic adventures, and found them more inspiring than ever -- though parts demand a charitable eye
I’ve been tempted to read this. Thanks for the thoughtful review! This is some great writing Jason.
Liked a tweet by Tai-Danae Bradley (@math3ma) (Twitter)
Bookmarked At the Interface of Algebra and Statistics by Tai-Danae Bradley (arXiv.org)
This thesis takes inspiration from quantum physics to investigate mathematical structure that lies at the interface of algebra and statistics. The starting point is a passage from classical probability theory to quantum probability theory. The quantum version of a probability distribution is a density operator, the quantum version of marginalizing is an operation called the partial trace, and the quantum version of a marginal probability distribution is a reduced density operator. Every joint probability distribution on a finite set can be modeled as a rank one density operator. By applying the partial trace, we obtain reduced density operators whose diagonals recover classical marginal probabilities. In general, these reduced densities will have rank higher than one, and their eigenvalues and eigenvectors will contain extra information that encodes subsystem interactions governed by statistics. We decode this information, and show it is akin to conditional probability, and then investigate the extent to which the eigenvectors capture "concepts" inherent in the original joint distribution. The theory is then illustrated with an experiment that exploits these ideas. Turning to a more theoretical application, we also discuss a preliminary framework for modeling entailment and concept hierarchy in natural language, namely, by representing expressions in the language as densities. Finally, initial inspiration for this thesis comes from formal concept analysis, which finds many striking parallels with the linear algebra. The parallels are not coincidental, and a common blueprint is found in category theory. We close with an exposition on free (co)completions and how the free-forgetful adjunctions in which they arise strongly suggest that in certain categorical contexts, the "fixed points" of a morphism with its adjoint encode interesting information.