
Quantum fluctuations have been shown to affect macroscopic objects - sohkamyung
https://www.nature.com/articles/d41586-020-01914-4
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perl4ever
"A special case of squeezed light, known as the squeezed vacuum, forms when
the average amplitude of the light is zero."

I love this. Don't ask me what it means.

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knodi123
Such conceptually dense language! Isn't the average amplitude of _every_ wave
just zero?

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stallmanite
Hmm, at least with an audio waveform one can have a DC offset wherein the
average is not zero.

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alanbernstein
The DC offset does not manifest when the waveform is translated into sound,
which is an actual propagating wave, the appropriate analogy to light.

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sharpneli
Almost but not quite. With light the electric field can go negative and the
average is generally 0. With sound in air the pressure component has a ”DC”
offset of 1bar and it cannot go negative, you will just get nonlinear effects
when you start nearing that limit.

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artpop
On quantum interferometer, I’ve always wondered if you could use it for
navigation in space. Say you send a probe to another system. Navigating the
uncharted system with precise gravity measurements that also expose its
kinematics would be handy.

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plafl
Physicist help needed: From my near null knowledge of quantum mechanics it
seems they decrease randomness in phase and amplitude measurement by
increasing uncertainty in mirrors position. So, this is interesting because
the mirrors are macroscopic objects that interacted with the light in a rather
simple way and conditions. On the other hand... Don't they require the mirror
position in a well determined position to measure the gravitational waves?

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c1ccccc1
They are increasing the precision of the phase while decreasing the precision
of the amplitude. Since the amplitude of the light determines how hard it
pushes on the mirrors, this has the side-effect of also making the positions
of the mirrors more uncertain. To get the most accurate measurement possible,
I'd guess that they would squeeze the light until getting any additional
precision in the phase was not worth the added noise in mirror position.

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martinclayton
Out of context perhaps, but rings true:

"...SQL is a direct consequence of the Heisenberg uncertainty principle..."

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The_rationalist
I don't understand yet I know the uncertainty principle, would you mind to
explain?

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tadhgf
It's a joke about about SQL databases misbehaving, not physics

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foxes
In gravitational wave detectors.

Heard of the Casimir effect? Two plates can experience a force from vacuum
fluctuations.

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kkylin
Small but important correction: two _conducting_ plates.
[https://en.wikipedia.org/wiki/Casimir_effect](https://en.wikipedia.org/wiki/Casimir_effect)

Also works in other geometries, e.g., sphere and plate, two spheres, etc.
First experimental verification was a sphere and a plate, I think?
[https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.78...](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.78.5)

