author : Sean M. Carroll

This is the course guidebook that accompanies the 24 lecture “Great Course” of the same name. It is essentially an abbreviated transcript of each lecture, a few pictures, and some related reading. (I watched the lectures, which is what I am reviewing here, and am using the book simply as an aide-memoire.)

This is a tour de force explanation of why our best model of the universe contains mostly stuff we know very little about, and have never directly detected: dark matter and dark energy.

Carroll spans the Big Bang, cosmology, and the Standard Model of particle physics, with beautifully lucid descriptions, intuitions, and inferences.

This was written and recorded before the discovery of the Higgs boson, and, perhaps more importantly, before the failure to discover supersymmetric particles, so some of the speculations are outdated. However, these are noted as speculations, and it is interesting to see the reasoning behind ideas that have not panned out.

Recommended.

This is the course guidebook that accompanies the 12 lecture “Great Course” of the same name. It is essentially an abbreviated transcript of each lecture, a few pictures, and some related reading. (I watched the lectures, which is what I am reviewing here, and am using the book simply as an aide-memoire.)

Carroll is a brilliant lecturer. He manages to make the most mind-manglingly complex ideas understandable and relatable, without ever taking down. Here the focus is on the discovery of the Higgs boson, the final missing piece in the Standard Model of particle physics. He gives us the background physics, including a great explanation of what a guage theory is, and why the Higgs is important; he also gives the history of the discovery, and what an amazing engineering and scientific feat that was.

This is eight years after his equally excellent lecture course on Dark Matter and Dark Energy. That was before the Higgs was discovered; now it has been. But there is equal speculation about supersymmetry: even now (2024), those hypothesised particles have not been discovered, nor do there seem to be any hints of their existence. So, with the Higgs we now have a complete understanding of 5% of the universe, that described by the Standard Model, itself unchanges soince the 1970s. As for the remaining 95%, not to mention the infationary field in the early universe, well, maybe a later lecture series will be able to tell us more.

In this ambitious work, Carroll covers an enormous range: fundamental physics, cosmology, epistemology, complexity, consciousness, morality.

He shows how (our best current understanding of) fundamental physics allows no room for any ghosts in the machine. He explains the philosophical position of “poetic naturalism”, and how it can be used to tell (well-founded, scientific) “stories” about the emergent macro-world that don’t need to reduce everything to quantum physics, but how this necessarily means we have to omit certain aspects when telling these stories. And he introduces Bayesian reason as a technique for improving understanding at all levels.

This is a bold endeavour, cramming much profound material into 50 chapters, each less than 10 pages, but adding up to over 400 pages of fascinating material. He has interesting insights on a wide range of topics, not just his own speciality of quantum physics, but also epistemology, emergence, complexity, and more. It is a deeply humanistic account, yet grounded in the cold hard light of the constraints of physical reality.