Cactus Code Thorn HydroBase
Author(s)    : Erik Schnetter 
Maintainer(s): Erik Schnetter 
Licence      : LGPL
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1. Purpose

Provide storage for the hydro variables



2. Definitions

The HydroBase variables correspond to the Valencia formulation.

HydroBase uses the following conventions:
  M = M_sun
  c = G = 1

We also assume the following constants of nature:
  c     = 299792458.0 m/s
  G     = 6.67428e-11 m^3/kg/s^2
  mu0   = 4 pi 1.0e-7 N/A^2
  eps0  = 1 / (mu0 c^2)
  M_sun = 1.98892e+30 kg

This corresponds to the following units:
  [M] = M_sun
  [L] = [M] (G / c^2)
  [T] = [L] / c
  [B] = 1 / [L] / sqrt(eps0 G / c^2))