3 * Interface to GiNaC's clifford algebra (Dirac gamma) objects. */
6 * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #ifndef __GINAC_CLIFFORD_H__
24 #define __GINAC_CLIFFORD_H__
32 /** This class holds an object representing an element of the Clifford
33 * algebra (the Dirac gamma matrices). These objects only carry Lorentz
34 * indices. Spinor indices are hidden. */
35 class clifford : public indexed
37 GINAC_DECLARE_REGISTERED_CLASS(clifford, indexed)
41 clifford(const ex & b);
42 clifford(const ex & b, const ex & mu);
44 // internal constructors
45 clifford(const exvector & v, bool discardable = false);
46 clifford(exvector * vp); // vp will be deleted
48 // functions overriding virtual functions from base classes
50 ex simplify_ncmul(const exvector & v) const;
51 ex thisexprseq(const exvector & v) const;
52 ex thisexprseq(exvector * vp) const;
53 unsigned return_type(void) const { return return_types::noncommutative; }
54 unsigned return_type_tinfo(void) const { return TINFO_clifford; }
58 /** This class represents the Clifford algebra unity element. */
59 class diracone : public tensor
61 GINAC_DECLARE_REGISTERED_CLASS(diracone, tensor)
63 // functions overriding virtual functions from bases classes
65 void print(const print_context & c, unsigned level = 0) const;
69 /** This class represents the Dirac gamma Lorentz vector. */
70 class diracgamma : public tensor
72 GINAC_DECLARE_REGISTERED_CLASS(diracgamma, tensor)
74 // functions overriding virtual functions from bases classes
76 void print(const print_context & c, unsigned level = 0) const;
77 bool contract_with(exvector::iterator self, exvector::iterator other, exvector & v) const;
82 inline const clifford &ex_to_clifford(const ex &e)
84 return static_cast<const clifford &>(*e.bp);
88 /** Create a Clifford unity object.
90 * @return newly constructed object */
93 /** Create a Dirac gamma object.
95 * @param mu Index (must be of class varidx or a derived class)
96 * @return newly constructed gamma object */
97 ex dirac_gamma(const ex & mu);
102 #endif // ndef __GINAC_CLIFFORD_H__