Category Archives: Uncategorized

Some Interviews

Some interviews that readers of this blog may find of interest: David Zierler at the AIP interviews Lee Smolin (April 1, 2021). David Zierler at the AIP interviews Stephon Alexander (June 7, 2021). Alexis Papazoglou at IAI News interviews me … Continue reading

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The Trouble With Path Integrals, Part II

This posting is about the problems with the idea that you can simply formulate quantum mechanical systems by picking a configuration space, an action functional S on paths in this space, and evaluating path integrals of the form $$\int_{\text{paths}}e^{iS[\text{path}]}$$ Necessity … Continue reading

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The Trouble With Path Integrals, Part I

Two things recently made me think I should write something about path integrals: Quanta magazine has a new article out entitled How Our Reality May Be a Sum of All Possible Realities and Tony Zee has a new book out, … Continue reading

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What’s Going Right in Particle Physics

Since I had a little free time today, I was thinking of writing something motivated by two things I saw today, Sabine Hossenfelder’s What’s Going Wrong in Particle Physics, and this summer’s upcoming SUSY 2023 conference and pre-SUSY 2023 school. … Continue reading

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Various and Sundry

A few things that may be of interest: Fermilab is continuing to push the wormhole publicity stunt, with Joe Lykken, the lab’s Deputy director for research on the 17th giving a public lecture on Wormholes in the Laboratory. The promotional … Continue reading

Posted in Uncategorized, Wormhole Publicity Stunts | 9 Comments

What is the AdS/CFT Conjecture?

In recent years I’ve found there’s no point to trying to have an intelligible argument about “string theory”, simply because the term no longer has any well-defined meaning. At the KITP next spring, there will be a program devoted to … Continue reading

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Spring Course

This semester I’m teaching the second half of our graduate course on Lie groups and representations, and have started making plans for the course, which will begin next week. There’s a web-page here which I’ll be adding to as time … Continue reading

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Pierre Schapira on Récoltes et Semailles

Earlier this year I bought a copy of the recently published version of Grothendieck’s Récoltes et Semailles, and spent quite a lot of time reading it. I wrote a bit about it here, intended to write something much longer when … Continue reading

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Various and Sundry

If you’re sick of hearing about bogus wormholes, here are some other random topics: There’s a SCOAP3 for books initiative, lots of textbooks in the field of particle physics now made open access and available here. It’s completely mysterious to … Continue reading

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Comments on AdS/CFT

This is something I wrote back in June, for context see the next posting. First of all, there’s the following, which is not strictly scientific, but very relevant to how one decides to evaluate progress in a subject. The Maldacena … Continue reading

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