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/* Copyright (C) 2004 Viktor T. Toth <http://www.vttoth.com/>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* Demonstrate torsion and nonmetricity
*
*/
if get('ctensor,'version)=false then load(ctensor);
("We use a simple 2D metric to demonstrate torsion and nonmetricity")$
ct_coordsys(cartesian2d);
ug:invert(lg);
("In a flat metric, the Christoffel symbols are zero")$
christof(false);
cdisplay(mcs);
("Let us examine how torsion changes this")$
ctorsion_flag:true;
christof(false);
cdisplay(mcs);
("And now recalculate the Christoffel symbols with nonmetricity")$
ctorsion_flag:false;
cnonmet_flag:true;
christof(false);
cdisplay(mcs);
("The arrays tr and nm are user-defined.")$
/* End of demo -- comment line needed by MAXIMA to resume demo menu */
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