The NIST QMRNG

[Jim Cheetham]

I just came across an article discussing NIST's recent work on a
"guaranteed random" generation mechanism.

https://www.theregister.co.uk/2018/04/11/nist_random_numbers_quantum_mechanics/

The paper is published in Nature, 11 April 2018:
https://www.nature.com/articles/s41586-018-0019-0

The idea seems to be that entangled photon can have their polarisation
states measured in such a way that violates the usual expectation that
"experimental outcomes are governed by pre-existing local attributes
of particles being measured"

This apparently leaves us with a randomised state that is not
dependent on pre-existing conditions; i.e. one that is actually
random, rather than the standard that we usually use, which is "the
state is predictable but we don't have sufficient measurements to be
able to do the prediction".

It's easy to see how tossing a coin or a die could be predicted given
sufficient information about how the toss was performed, for example.
In a similar way, the thermal and electrical properties of OneRNGs
diodes might be predictable - although I've not heard anyone suggest
that this is a practical procedure, except in the extreme case of
malfunctions.

But NIST's approach might be significantly 'better', except that with
the current implementation you'd need the USB stick to be a triangle
over 100m on each side, which isn't exactly going to fit in the post
from China ...

-jim