It has been suggested that the uncertainty in the measurement of a particle's momentum could be made arbitrarily small by observing the particle at two ends of an arbitrarily long flight path. However, consideration of the nature of the detection process shows that the usual limits of the uncertainty principle hold independent of the length of the flight path.
It has been suggested that the uncertainty in the measurement of a particle's momentum could be made arbitrarily small by observing the particle at two ends of an arbitrarily long flight path. However, consideration of the nature of the detection process shows that the usual limits of the uncertainty principle hold independent of the length of the flight path.
Because the particles follow a wave pattern of probability prescribed by schrodinger equation and we are guided by uncertainty principles, we often wrongly interpret the nature of reality. Heisenberg only prescribes the measurement problems of very small due to limitations of wave length of the observing beam and that is the natural limitation but wrongly we say that nature is acting indeterministi. Thus we wrongly understand uncertainty principles connecting t to saying that nature can never be precisely defined in momentum and position.In the same way we measure time in relativity theory confusing the very notion of time.
According to a new extension to an old theory, a particle's position cannot be measured precisely even if its momentum is not measured simultaneously.By Charles Day H eisenberg's uncertainty principle limits the precision with which two observables that do not commute with each other can be simultaneously measured.The Wigner-Araki-Yanase (WAY) theorem goes further.If observables A and B do not commute, and if observable A is conserved, observable B cannot be measured with arbitrary precision even if A is not measured at all.In its original 1960 formulation, the WAY theorem applied only to observables, such as spin, whose possible values are discrete and bounded.Now Yui Kuramochi of Kyushu University and Hiroyasu Tajima of the University of Electro-Communications-both in Japan-have proven that the WAY theorem also encompasses observables, such as position, that are continuous and unbounded [1].Besides resolving the decades-long problem of how to deal with such observables, the extension will likely find practical applications in quantum optics.The difficulty of extending the WAY theorem arose from how an
Standard-deviation and entropic formulations of uncertainty principle capture the spread of the probability distribution but say little about the probability itself contained in a small region. We introduce the confidence uncertainty Δcx(θx) as the minimal Lebesgue measure of the support set in which the particle is found with probability at least θx, and the companion interval confidence uncertainty ΔIx(θx) which restricts the support to a single interval. We prove two complementary uncertainty inequalities. (i) For θx+θp≤1 both confidence uncertainties can be made arbitrarily small simultaneously, so that no nontrivial product bound holds; in particular, position and momentum can be jointly localised with probability at least~50%. (ii) For θx+θp>1 a lower bound holds: combining Lenard's projection inequality with the Donoho--Stark operator-norm bound we obtain ΔcxΔcp≥2πℏ(θxθp−(1−θx)(1−θp))2, and for the interval version we obtain the sharp implicit Landau--Pollak bound ΔIxΔIp≥4ℏλ0−1((θxθp−(1−θx)(1−θp))2), where λ0(c) is the largest prolate-spheroidal eigenvalue. We support the analytical bounds with numerical evaluation of λ0(c), provide closed-form small-c and large-c asymptotics, compute the optimal Slepian-superposition states that saturate the interval bound, and compare the resulting product against the variance Heisenberg--Kennard, the Białynicki-Birula--Mycielski entropic, and the Donoho--Stark concentration bounds. The unified picture provides a complete phase diagram on (θx,θp)∈[0,1]2.