Must...diffuse...faster!!

[zaimoni]

University of Bonn makes progress on transforming atoms into the Flash:In less politically correct times, physics professors explained the random walk as follows. Suppose a drunk stands under a lamppost, staggering to the right or left with equal probability. After some number of steps, N, he is likely to have taken a few more steps to the left

Comments

[sir_dave]

Proportional to N and not root N? Ow. Quantum Mechanics should not be expected to make 'sense', but this is playing with probability itself, one of the few things that one learns to rely on in the Quantum world.

[zaimoni]

More importantly, it's playing with when the probability is invoked.

There's nothing probabilistic about how the solutions to the (relativistic) Schrödinger equation itself changes over time. The probability distribution manifests only when observation happens -- and that distribution, even in simple cases, usually corresponds to the countably infinitely many indexed eigenvalues for a countably infinitely dimensional matrix.

The really fun thing is that the laser setup doesn't count as observation. It makes me wonder what else doesn't count as observation.

(Most of these eigenvalues are small enough never to be empirically measured, but still numerically modeling this is painful. And simulate??? The state of the art is doing good to be able to calculate heat of formation from first principles for methane. [This hit the GAMESS quantum chemistry software April 2008; I might resume locally forking GAMESS from the Jan 2009 release if I can figure out how to make it tolerate excessively precise arithmetic.])

[marmoe]

In case you have not found it yet, here's a version of the paper on arXiv.

[zaimoni]

Thanks. It'll get a more detailed reading later (have done a skim and made sure all the notation has been proofread properly).

I'm curious as to what technical issues are causing their setup to start going classical at 11 steps. [This sort of initial condition abuse is mildly related to at least three civilizations' worth of alien technologies in my science fantasy.]