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Quantum microphone counts particles of sound (stanford.edu)
44 points by nabla9 69 days ago | hide | past | web | favorite | 7 comments



> “Quantum mechanics tells us that position and momentum can’t be known precisely – but it says no such thing about energy,” Safavi-Naeini said. “Energy can be known with infinite precision.”

There is actually a time-energy uncertainty relation. https://en.wikipedia.org/wiki/Uncertainty_principle


The original quote is too ambiguous for me to parse, but I feel compelled to mention that we should be careful with time-energy uncertainty. Time is usually not considered an observable in quantum theory, so it can be tricky to talk about time uncertainty.


Resolving the energy levels of a nanomechanical oscillator https://www.nature.com/articles/s41586-019-1386-x


This is 23rd Century Technology.

Let me explain.

See, the general pattern here is transducer + miniaturization. Maybe that makes for a microphone if you apply it to sound, but what I would like to see is the ability to fabricate ultra-small transducers for every known wavelength / electromagnetic spectrum phenomena.

Then for Act II... put those suckers in an array...

Can anybody say Star Trek Tricorder?

Actually, even a would-be Tricorder is a limited application... the real applications range from everything from electron microscopes to radiotelescopes, and everything in between.

Reversed, you could possibly get different types of field modulation out of such an array... need an electromagnetic field of whatever frequency and form for whatever purpose? That is, a universal field generator?

First step, right here.

Not just brilliant, but utterly, utterly, utterly brilliant!

This is my new #1 favorite EVER, on HN!


I find this totally amazing. This feels like it could be an extremely sensitive and fast signaling channel. I wonder what the relationship of these atomic vibrations have to the microscopic behavior of electric current. I.e. can current be described as phonons traveling through metal?


Perhaps of interest as an aside:

In trapped ion quantum systems the shared motional phonons ("sound quanta") are how 2-qubit gates are effected. If I remember the steps correctly:

1) Cool a string of ions to their motional ground state in a shared harmonic potential (the ion trap) 2) Issue laser pulses to ion 1 to create an entangled state that couples the ion's internal excited state to 1 quanta of one of the shared motional phonon mode 3) Issue a similar laser pulse to ion 2, this one exciting it conditional on the presence of the motional phonon

Now your two ions are entangled.


> Like unruly inmates, the trapped phonons rattle the walls of their prisons

This is pure poetry!




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