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'Quantum negativity' can power ultra-precise measurements
Phys.org ^ | July 29, 2020 | by University of Cambridge

Posted on 07/29/2020 8:08:06 AM PDT by BenLurkin

Metrology is the science of estimations and measurements.

We are used to dealing with probabilities that range from 0% (never happens) to 100% (always happens). To explain results from the quantum world however, the concept of probability needs to be expanded to include a so-called quasi-probability, which can be negative. This quasi-probability allows quantum concepts such as Einstein's 'spooky action at a distance' and wave-particle duality to be explained in an intuitive mathematical language.

An experiment whose explanation requires negative probabilities is said to possess 'quantum negativity.'

In state-of-the-art metrology however, the probes are quantum particles, which can be controlled at the sub-atomic level. These quantum particles are made to interact with the thing being measured. Then the particles are analyzed by a detection device.

In theory, the greater number of probing particles there are, the more information will be available to the detection device. But in practice, there is a cap on the rate at which detection devices can analyze particles.

"We've adapted tools from standard information theory to quasi-probabilities and shown that filtering quantum particles can condense the information of a million particles into one," said lead author David Arvidsson-Shukur ... "That means that detection devices can operate at their ideal influx rate while receiving information corresponding to much higher rates. This is forbidden according to normal probability theory, but quantum negativity makes it possible."

Quantum metrology can improve measurements of things including distances, angles, temperatures and magnetic fields. These more precise measurements can lead to better and faster technologies...

Quantum metrology is currently used to enhance the precision of gravitational wave detection in the Nobel Prize-winning LIGO Hanford Observatory. But for the majority of applications, quantum metrology has been overly expensive and unachievable with current technology. The newly-published results offer a cheaper way of doing quantum metrology.

(Excerpt) Read more at phys.org ...


TOPICS: Science
KEYWORDS: metrology; quantummetrology; quantumnegativity; stringtheory

1 posted on 07/29/2020 8:08:06 AM PDT by BenLurkin
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To: SunkenCiv

gnip


2 posted on 07/29/2020 8:08:36 AM PDT by BenLurkin (The above is not a statement of fact. It is either opinion or satire. Or both.)
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To: BenLurkin

That explains what powers the left: MASSIVE Negativity.


3 posted on 07/29/2020 8:12:22 AM PDT by freedumb2003 ("Do not mistake activity for achievement." - John Wooden)
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To: BenLurkin
“When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science.” ― Lord Kelvin
4 posted on 07/29/2020 8:17:05 AM PDT by Red Badger (To a liberal, 9-11 was 'illegal fireworks activity'..........................)
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To: BenLurkin

“the concept of probability needs to be expanded to include a so-called quasi-probability, which can be negative. This quasi-probability allows quantum concepts such as Einstein’s ‘spooky action at a distance’ and wave-particle duality to be explained in an intuitive mathematical language.

An experiment whose explanation requires negative probabilities is said to possess ‘quantum negativity.’

In state-of-the-art metrology however, the probes are quantum particles, which can be controlled at the sub-atomic level. These quantum particles are made to interact with the thing being measured. Then the particles are analyzed by a detection device.

In theory, the greater number of probing particles there are, the more information will be available to the detection device. But in practice, there is a cap on the rate at which detection devices can analyze particles.

“We’ve adapted tools from standard information theory to quasi-probabilities and shown that filtering quantum particles can condense the information of a million particles into one,” said lead author David Arvidsson-Shukur ... “That means that detection devices can operate at their ideal influx rate while receiving information corresponding to much higher rates. This is forbidden according to normal probability theory, but quantum negativity makes it possible.”

Quantum metrology can improve measurements of things including distances, angles, temperatures and magnetic fields. These more precise measurements can lead to better and faster technologies...”

Well, DUH!


5 posted on 07/29/2020 8:23:21 AM PDT by lowbridge
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To: 6SJ7; AdmSmith; AFPhys; Arkinsaw; allmost; aristotleman; autumnraine; bajabaja; ...
Thanks BenLurkin. I'm thinkin' this is somehow related to the speed of dark.
Believe it or not, I'm making this a superconductivity ping.

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6 posted on 07/29/2020 8:30:34 AM PDT by SunkenCiv (Imagine an imaginary menagerie manager imagining managing an imaginary menagerie.)
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To: BenLurkin

Negative probability is absurd but only if you subscribe to the interpretation that quantum probabilities as defined by the Born rules is a “frequentist” probability (like coin tosses) and not “epistemological” probability (like Bayes’ theorem of apriori estimates of expected outcomes).

The fact that quantum information storage can violate classical information theory entropy principles is because we continue to try to understand the wave function of the universe in classical terms based on decoherence and “objective” observations “outside” the system. There is no “outside the system” when it comes to QFT. Hilbert space has its own dynamics and when we compute probabilities by squaring wave function amplitudes we can easily miss the subtleties of entanglement and superpositions of states. We interpret this ignorance as “negative probability” but it just means we aren’t wired to get our heads around what is “real” about QFT.


7 posted on 07/29/2020 9:30:14 AM PDT by Dave Wright
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To: Dave Wright

What is QFT?


8 posted on 07/29/2020 9:35:23 AM PDT by BenLurkin (The above is not a statement of fact. It is either opinion or satire. Or both.)
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