This isn’t from The Onion—” ‘real’ or from The Onion” is macro uncertainty—it seems that, by being clever, it’s possible to do somewhat better measurement of subatomic particles than was expected. Does the article look sound? If so, what are some implications?
The title of that article is extremely misleading. The uncertainty principle, as understood in contemporary physics, is a consequence of the (extremely well-confirmed) laws of quantum mechanics. Momentum-space wavefunctions in quantum mechanics are Fourier transforms of position-space wavefunctions. As a consequence, the more you concentrate a wavefunction in position space, the more it spreads out in momentum space, and vice versa. More generally, there will be an “uncertainty principle” associated with any two non-commuting observables (two operators A and B are non-commuting if AB—BA is not 0). Any experiment challenging this version of the uncertainty principle would be contradicting the basic math of quantum mechanics, and the correct response would be to defy the data.
But this experiment does not challenge the uncertainty principle, it challenges Heisenberg’s original interpretation of the uncertainty principle. Rather than seeing the principle as a simple consequence of the mathematical relationship between position and momentum, Heisenberg concocted a physical explanation for the principle that appealed to classical intuitions. According to his interpretation, the uncertainty principle is a consequence of the fact that any attempt to measure the position of a particle (by say, bouncing photons off it) disturbs the particle, which leads to a change in its momentum. The correct mathematical explanation of the uncertainty principle, given above, does not make any reference to measurement or disturbance, you’ll notice.
Anyway, this experiment only challenges Heisenberg’s version of the uncertainty principle, not the actual uncertainty principle. Far from contradicting the math of quantum mechanics, the falsity of Heisenberg’s interpretation is actually predicted by that math, as shown by Ozawa. The abstract of the paper you link makes it clear that the authors are distinguishing between the actual uncertainty principle and Heisenberg’s interpretation:
While there is a rigorously proven relationship about uncertainties intrinsic to any quantum system, often referred to as “Heisenberg’s uncertainty principle,” Heisenberg originally formulated his ideas in terms of a relationship between the precision of a measurement and the disturbance it must create. Although this latter relationship is not rigorously proven, it is commonly believed (and taught) as an aspect of the broader uncertainty principle.
I guess you could refer to Heisenberg’s interpretation of the uncertainty principle as “Heisenberg’s uncertainty principle”, but it seems to me that that is just a recipe for confusion. Intelligent laypeople will get the impression that this is some profound and fundamental sea-change in the foundations of quantum mechanics. It isn’t.
I’m wondering (assuming that the work pans out) whether there would be technological implications even though the foundations of physics aren’t shaken at all.
Physicists cast doubt on renowned uncertainty principle.
This isn’t from The Onion—” ‘real’ or from The Onion” is macro uncertainty—it seems that, by being clever, it’s possible to do somewhat better measurement of subatomic particles than was expected. Does the article look sound? If so, what are some implications?
The title of that article is extremely misleading. The uncertainty principle, as understood in contemporary physics, is a consequence of the (extremely well-confirmed) laws of quantum mechanics. Momentum-space wavefunctions in quantum mechanics are Fourier transforms of position-space wavefunctions. As a consequence, the more you concentrate a wavefunction in position space, the more it spreads out in momentum space, and vice versa. More generally, there will be an “uncertainty principle” associated with any two non-commuting observables (two operators A and B are non-commuting if AB—BA is not 0). Any experiment challenging this version of the uncertainty principle would be contradicting the basic math of quantum mechanics, and the correct response would be to defy the data.
But this experiment does not challenge the uncertainty principle, it challenges Heisenberg’s original interpretation of the uncertainty principle. Rather than seeing the principle as a simple consequence of the mathematical relationship between position and momentum, Heisenberg concocted a physical explanation for the principle that appealed to classical intuitions. According to his interpretation, the uncertainty principle is a consequence of the fact that any attempt to measure the position of a particle (by say, bouncing photons off it) disturbs the particle, which leads to a change in its momentum. The correct mathematical explanation of the uncertainty principle, given above, does not make any reference to measurement or disturbance, you’ll notice.
Anyway, this experiment only challenges Heisenberg’s version of the uncertainty principle, not the actual uncertainty principle. Far from contradicting the math of quantum mechanics, the falsity of Heisenberg’s interpretation is actually predicted by that math, as shown by Ozawa. The abstract of the paper you link makes it clear that the authors are distinguishing between the actual uncertainty principle and Heisenberg’s interpretation:
I guess you could refer to Heisenberg’s interpretation of the uncertainty principle as “Heisenberg’s uncertainty principle”, but it seems to me that that is just a recipe for confusion. Intelligent laypeople will get the impression that this is some profound and fundamental sea-change in the foundations of quantum mechanics. It isn’t.
Thanks.
I’m wondering (assuming that the work pans out) whether there would be technological implications even though the foundations of physics aren’t shaken at all.