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"Exact uncertainty" brought to quantum world
NewScientist.com ^
| April 02
| Eugenie Samuel
Posted on 05/07/2002 11:50:28 AM PDT by sourcery
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1
posted on
05/07/2002 11:50:29 AM PDT
by
sourcery
To: Physicist; longshadow; RightWhale
FYI
2
posted on
05/07/2002 12:02:23 PM PDT
by
sourcery
To: sourcery
Wolfgang Schleich An important name in optics, theoretical physics. Dropping the name here increases the modality of this exact uncertainty theory.
To: sourcery
This article doesn't make much sense. Population sampling statistics do not involve immediately mutual effects, and I think that mutual measurement effect interaction has a role in further specifying the uncertainty. Here's hoping that the new equation is not simply the inequality after removing the "or greater than". It seems to me that the image analysis field has provided more food for thought on the same topic. One relevant concept in that field is the Fisher matrix.
To: sourcery
The result is an expression that looks like Heisenberg's original relation, but gives the exact uncertainty in the measurements of position and momentum. Hall says it is an equation rather than an inequality, which is "a far stronger relation". But it will still be an inequality. Nothing prevents you from having a more uncertain measurement than that allowed by the uncertainty relation, whatever that relation might be.
5
posted on
05/07/2002 12:23:53 PM PDT
by
Physicist
To: sourcery
bttt
To: sourcery
Thumbtack.
7
posted on
05/07/2002 1:10:51 PM PDT
by
AndrewC
To: sourcery
dp dx = h / (2 x pi) + y
See, I can do it too. ; )
To: apochromat
But the question then surfaces of whether or not the quantity of uncertainty required differs with differing external environmental or statistical situations, if so, that implies that you could extract energy from the quantum uncertainty..
To: Technocrat
Is it just me, or does reading that without thinking about it make you laugh?
To: RadioAstronomer; ThinkPlease; PatrickHenry; VadeRetro; Scully; edwin hubble; Doctor Stochastic
Does this mean Schrödinger's Cat is more dead (and more NOT dead) than we used to think it was?
To: Technocrat
I think spontaneous energy beneath the uncertainty floor is "imaginary" energy, "imaginary" in the same way the impedances in a network of perfect capacitors and inductors are imaginary.
To: sourcery
BUMP for later read
To: Physicist
I just skimmed the paper but it looks like the measured uncertainty is greater than the "intrinsic" [my name, not theirs] uncertainty because of the Cramer-Rao inequalities. The paper's equality is between the dispersions of the conjugate variables.
To: Physicist
Nothing prevents you from having a more uncertain measurement than that allowed by the uncertainty relation, whatever that relation might be. Soitinly! (or a reasonable facsimile of that pronunciation).
15
posted on
05/07/2002 2:09:44 PM PDT
by
AndrewC
To: longshadow
The result is an expression that looks like Heisenberg's original relation, but gives the exact uncertainty in the measurements of position and momentum. Lemme see now ... I'm no QM man, but I guess this means that we used to be uncertain about how much uncertainty there was in such matters. Now we are less so. The article makes it sound as if we are far less so. This sounds like a significant improvement. But QM is definitely outside the range of my conversational topics.
To: PatrickHenry
We used to know that we didn't know and we knew how much we didn't know. Now we know by how much we don't know that we don't know. Y'know.
To: Doctor Stochastic
Now we know by how much we don't know that we don't know. People always feel that they have a handle on something if they can stick numbers to it. It's a control thing.
To: PatrickHenry
This sounds like a significant improvement. But QM is definitely outside the range of my conversational topics. This is clearly a topic within the domain of "Plato the Platypus"....... [creating yet another posting opportunity for the jpg image of "Plato," the fuzzy, furry, and maniacal monotreme.]
To: longshadow
[creating yet another posting opportunity for the jpg image of "Plato," the fuzzy, furry, and maniacal monotreme.]How about the opportunity for the personal primate assistant?
Who rates the article on which this thread is based, 0 BS. There is no BS in it.
20
posted on
05/07/2002 4:10:57 PM PDT
by
AndrewC
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