
Simulating Physics - stefanpie
http://www.news.ucsb.edu/2017/018547/simulating-physics
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Koshkin
In this case, it looks like the goal was to demonstrate the power of quantum
computers rather than to use them in order gain a new insight into the physics
of the otherwise well-known phenomenon (the so-called "Anderson localization",
which is a "quantum-mechanical part" of the effect that impurities have on the
conductivity of a metal).

Speaking of the "non-goal", I am left wondering how much information is there
to be gained from looking _this closely_ (albeit by means of simulation) at
things that have been or, if not, perhaps could be described well enough
following the more traditional lines of statistical or phenomenological
investigation.

~~~
selimthegrim
Anderson localization and many-body localization are distinct. AL is a single-
particle phenomenon, considering wavefunctions and eigenstates of a single
electron at a time. MBL involves ensembles of manifestly many-electron/many-
body eigenstates. If you take a subsystem (a small window of eigenstates or
energy if you are in the microcanonical ensemble) and resample it, if you are
in the thermal regime it will recover the entire distribution of the extensive
quantity being sampled for the whole system (let's take entropy as an
example).

The goal is to eventually see how many-body localization scales (does the
experimental appearance vanish at large but finite time scales as is common in
implementations of the Bose-Hubbard model) and see if it can be harnessed as
either a form of passive quantum information protection/error correction
and/or useful in assisting speedup in solving certain adiabatic quantum
computing problems (this last has nothing to do with the Google experiment at
hand and more with the intersection of the problem with spin glasses)

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selimthegrim
I worked with the UCSB team on some of the thermalization calculations that
didn't end up making it into the paper (I am at a different university). It's
really cool to see how quickly phenomena we study in simulations came to the
forefront of experiment. The actual paper can be found here -
[https://arxiv.org/abs/1709.06678](https://arxiv.org/abs/1709.06678)

