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From: Matthias Troyer (troyer_at_[hidden])
Date: 20031022 14:51:13
On Wednesday, October 22, 2003, at 08:51 PM, Paul A. Bristow wrote:
> I (and others) also expressed the prejudice that all are kept as their
> base
> unit, now that 'everyone' is using at least 64bit doubles in their
> calculations
> (which is enough to keep everyone except the astronomers in the
> exponent range.
> And the significand precision available (15ish decimal digits) is
> ample for all
> physical measurements.
I want to disagree here. I know particle physicists who use singe
precision (float) numbers in some of their calculations. If instead of
a common choice of units where hbar=1 one uses SI unites, where hbar is
about about 1e34, there will be problems. Even worse problems come
when hbar^2 is needed.
Since for many calculations I do in quantum mechanics a natural set of
units is where hbar, the speed of light, and the charge of the electron
are set to one, I would not like to be forced to use SI units.
Matthias
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