Brian Wilcox, a researcher heading up the Robotic Subsurface Explorer task force at NASA’s Jet Propulsion Laboratory (JPL), explains how the Heisenberg Uncertainty Principle applies to targeting lasers at distant objects.
One formulation of Heisenberg's Uncertainty Principle is that the uncertainty in the momentum times the uncertainty in the position is greater than or equal to Plank's Constant. Symbolically, r*delta-p>h, where r is the radius of the hole which constrains the position of the particle, delta-p is the uncertainty in the momentum "p", and h (read "h-bar" but this is plain text so I don't have the special symbols) is Plank's constant. But now delta-p divided by p is the angular uncertainty delta-theta of the photon coming out of the exit aperture of the laser. So we have delta-theta=delta-p/p>h/rp. But the momentum of any particle (including photons) is 2(pi)h/lambda, where lambda is the wavelength of the particle. So delta-theta>lambda/2(pi)r. This is one version of "Rayleigh's Criterion", which is a principle of optics discovered even prior to Heisenberg stating his uncertainty principle, but which is in fact only a theorem provable from the universal statement by Heisenberg.
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