I’m halfway through Graham Farmelo’s Dirac biography at the moment, and enjoying it quite a bit. Farmelo cites Dirac as one of the first physicists to evaluate theories on their mathematical beauty, rather than waiting for experiments. This is in stark contrast to his Cambridge colleague Rutherford, who was highly skeptical of abstract theory, and… Continue reading Philosophical Poll: Chickens and Eggs, Experiment and Theory
Category: Physics
The Purposes and Problems of Labs
Over at Jim Henley’s place, Thoreau further justifies his status as an essential academic-physics blogger with a really good post about the problem of introductory labs: In freshman labs, generally you’re trying to measure something (at least as it’s done at many schools). The measurement is never as clean as the stuff being taught in… Continue reading The Purposes and Problems of Labs
Dorky Poll: State Manipulation
I’m teaching Quantum Optics again this term, talking about the interaction between light and matter in circumstances where you need to account for the quantum nature of one or both of those. We’re starting on the actual interactions today, albeit with a semi-classical approach (Einstein coefficients and the Fermi Golden Rule), but we’ve just finished… Continue reading Dorky Poll: State Manipulation
Stupid Technical Question: “Mass Insertion”
In reading a theoretical paper on electric dipole moments (well, OK, skimming through it looking for numbers), I ran across several Feynman diagrams with an “X” on one of the particle arrows. The caption contains the presumably-intended-to-be-helpful note “The cross denotes a mass insertion.” I have no idea what that means, and neither does the… Continue reading Stupid Technical Question: “Mass Insertion”
Schrödinger’s Virus?
The ArXiV Blog and several other sources last week linked to a new paper titled Towards Quantum Superposition of Living Organisms: The most striking feature of quantum mechanics is the existence of superposition states, where an object appears to be in different situations at the same time. Up to now, the existence of such states… Continue reading Schrödinger’s Virus?
The Speed of God
Over in Twitter-land, Eric Weinstein is visiting the AMNH at the same time as a bunch of Orthodox Jews, and takes the opportunity for a little Q&A: Me: Excuse me, but how is the phylogenetic tree reconciled with Torah. Modern Orthodox Man: Lorentzian time dilation. It’s a head hurter. This is an interesting attempt to… Continue reading The Speed of God
How Many Licks? or How to Estimate Damn Near Anything by Aaron Santos
One of the odd things about the C-list celebrity life of a semi-pro blogger is that I get a bunch of requests to review books on physics-related topics. Some of these take the form of a book showing up out of the blue, others are preceded by a polite request from the author. Aaron Santos’s… Continue reading How Many Licks? or How to Estimate Damn Near Anything by Aaron Santos
Dorky Poll: Explosive Elements
We did the far right column of the periodic table, so here’s one for the left: the coolest-chemistry-demo-ever column, the alkali metals: What’s your favorite alkali metal?(surveys) While you can make heteronuclear alkali dimers, at least in a transient way, we’re talking atoms here, not molecules. Choose only one.
Beauty’s Just Another Word I’m Never Certain How to Spell
Like every other blogger with a political opinion, I read Paul Krugman’s essay on economics last week, and tagged it for Saturday’s Links Dump. And while I appreciate Eric Weinstein calling me out as part of the “high end blogosphere,” I’m not sure I have much to say about it that is useful. But, since… Continue reading Beauty’s Just Another Word I’m Never Certain How to Spell
Quantum to Cosmos
I’m clearing out browser tabs before the weekend, which has reminded me that I’ve been terribly remiss in not passing along information about the Quantum to Cosmos festival being held next month at the Perimeter Institute in Waterloo, Ontario. For 10 exciting days this October, Perimeter Institute’s Quantum to Cosmos: Ideas for the Future (Q2C)… Continue reading Quantum to Cosmos