Why start?
A conversation with Wentao.
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Quantum Sensing Like a Bird
A few nights ago I was on a panel on Quantum Sensing for Defense. Preparing for this panel crystallized some ideas for me, which I think I should write down somewhere. So here it is! When we talk about "quantum sensing," we often imagine a single, exquisite, hyper-sensitive
Les Houches lecture notes
Spending a few days at Les Houches workshop on TFLN photonics 😄 Here are my lecture notes. These are currently a very rough draft, though fairly respectable looking... I used Gemini 2.5 pretty heavily to help prepare these notes. For example, I'd write up some notes on paper,
![Fidelity, Fisher Information, QCRB and All that [pt. 1]](/content/images/size/w600/2025/05/IMG_3285.jpeg)
Fidelity, Fisher Information, QCRB and All that [pt. 1]
What about those time-energy and number-phase uncertainty relations? The way the time-energy uncertainty was often explained to me when I first learned quantum mechanics felt pretty hand-wavy ... The QCRB solves this and puts these uncertainty relations on a proper footing.
Free Energy for Computer Scientists
If nature only cared about minimizing energy, all the gas molecules around us would collapse to the floor and we would suffocate. If nature only maximized entropy, all the gas would expand and disperse throughout the universe, and we would suffocate.