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Full Version: Physicists find a loophole in Heisenberg’s uncertainty principle without breaking it
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https://www.livescience.com/physics-math...reaking-it

EXCERPTS: Physicists have measured both the momentum and position of a particle without breaking Heisenberg’s iconic uncertainty principle.

In quantum mechanics, particles don’t have fixed properties the way everyday objects do. Instead, they exist in a haze of possibilities until they’re measured. And when certain properties are measured, others become uncertain. According to Heisenberg's uncertainty, it’s not possible to know both a particle’s exact position and its exact momentum at the same time.

But a new study has shown a clever loophole around this restriction. Physicists in Australia have demonstrated that by focusing on different quantities, known as modular observables, they can simultaneously measure position and momentum.

[...] In a grid state, the ion’s wave function is spread out into a series of evenly spaced peaks, like the marks on a ruler. The uncertainty is concentrated in the spaces between the marks. The researchers used the peaks as reference points: when a small force nudges the ion, the entire grid pattern shifts slightly. A small sideways shift of the peaks shows up as a change in position, while a tilt in the grid pattern reflects a change in momentum. Because the measurement only cares about the shifts relative to the peaks, both position and momentum changes can be read out at the same time... (MORE - details)
(Sep 29, 2025 09:42 PM)C C Wrote: [ -> ]https://www.livescience.com/physics-math...reaking-it

EXCERPTS: Physicists have measured both the momentum and position of a particle without breaking Heisenberg’s iconic uncertainty principle.

In quantum mechanics, particles don’t have fixed properties the way everyday objects do. Instead, they exist in a haze of possibilities until they’re measured. And when certain properties are measured, others become uncertain. According to Heisenberg's uncertainty, it’s not possible to know both a particle’s exact position and its exact momentum at the same time.

But a new study has shown a clever loophole around this restriction. Physicists in Australia have demonstrated that by focusing on different quantities, known as modular observables, they can simultaneously measure position and

I[...] n a grid state, the ion’s wave function is spread out into a series of evenly spaced peaks, like the marks on a ruler. The uncertainty is concentrated in the spaces between the marks. The researchers used the peaks as reference points: when a small force nudges the ion, the entire grid pattern shifts slightly. A small sideways shift of the peaks shows up as a change in position, while a tilt in the grid pattern reflects a change in momentum. Because the measurement only cares about the shifts relative to the peaks, both position and momentum changes can be read out at the same time... (MORE - details)

Cool. No physicist here but my layman senses went straight to …..

Sounds like they stopped time or discovered a moment. Perhaps they can measure the length of a moment also? Could this discovery be one step towards understanding time?
(Sep 30, 2025 01:14 PM)Zinjanthropos Wrote: [ -> ]Cool. No physicist here but my layman senses went straight to …..

Sounds like they stopped time or discovered a moment. Perhaps they can measure the length of a moment also? Could this discovery be one step towards understanding time?

I've heard of other "have your cake and eat it, too" experimental tricks in the past. They seem to either fade away or don't alter the usual QM platitude.

"Planck time" is the smallest meaningful unit of time (the interval it would take for a photon to travel a distance equal to one Planck length). If treated as corresponding to something real, then PT would be an insanely shorter moment than a milliseconds-long "giant" interval of our brain consciousness (that's the measurement of change for us). IOW, one of the latter experiential states would have to extend or endure over a string of countless co-existing Planck time changes. That "co-existence" consequence doesn't alter even when moving up to the "slower" level of "routine" subatomic events (measured in rontoseconds).
OP Wrote:..in a grid state, the ion’s wave function is spread out into a series of evenly spaced peaks
I'm thinking that the more you constrain the field of a particle (?) the more it (whatever the field is) behaves like a classical particle.