X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Fclifford.h;h=667d7befd9d400749188f8af6f28bcecee1ce83e;hp=d77707964f1d1d9f9dfb0d637f37fd48bbf705e9;hb=bc6dacb50cc13691efc466d2cc1900048158ec8d;hpb=3db194853d3dd2719231b83e4956cf6bcbe53627 diff --git a/ginac/clifford.h b/ginac/clifford.h index d7770796..667d7bef 100644 --- a/ginac/clifford.h +++ b/ginac/clifford.h @@ -3,7 +3,7 @@ * Interface to GiNaC's clifford algebra (Dirac gamma) objects. */ /* - * GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany + * GiNaC Copyright (C) 1999-2004 Johannes Gutenberg University Mainz, Germany * * 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 @@ -25,6 +25,8 @@ #include "indexed.h" #include "tensor.h" +#include "symbol.h" +#include "idx.h" namespace GiNaC { @@ -33,7 +35,7 @@ namespace GiNaC { * algebra (the Dirac gamma matrices). These objects only carry Lorentz * indices. Spinor indices are hidden. A representation label (an unsigned * 8-bit integer) is used to distinguish elements from different Clifford - * algebras (objects with different labels commute). */ + * algebras (objects with different labels commutate). */ class clifford : public indexed { GINAC_DECLARE_REGISTERED_CLASS(clifford, indexed) @@ -41,11 +43,11 @@ class clifford : public indexed // other constructors public: clifford(const ex & b, unsigned char rl = 0); - clifford(const ex & b, const ex & mu, unsigned char rl = 0); + clifford(const ex & b, const ex & mu, const ex & metr, unsigned char rl = 0); // internal constructors - clifford(unsigned char rl, const exvector & v, bool discardable = false); - clifford(unsigned char rl, std::auto_ptr vp); + clifford(unsigned char rl, const ex & metr, const exvector & v, bool discardable = false); + clifford(unsigned char rl, const ex & metr, std::auto_ptr vp); // functions overriding virtual functions from base classes protected: @@ -58,7 +60,10 @@ protected: // non-virtual functions in this class public: - unsigned char get_representation_label() const {return representation_label;} + unsigned char get_representation_label() const { return representation_label; } + ex get_metric() const { return metric; } + ex get_metric(const ex & i, const ex & j) const; + bool same_metric(const ex & other) const; protected: void do_print_dflt(const print_dflt & c, unsigned level) const; @@ -67,6 +72,7 @@ protected: // member variables private: unsigned char representation_label; /**< Representation label to distinguish independent spin lines */ + ex metric; }; @@ -82,10 +88,30 @@ protected: }; +/** This class represents the Clifford algebra generators (units). */ +class cliffordunit : public tensor +{ + GINAC_DECLARE_REGISTERED_CLASS(cliffordunit, tensor) + + // other constructors +protected: + cliffordunit(unsigned ti) : inherited(ti) {} + + // functions overriding virtual functions from base classes +public: + bool contract_with(exvector::iterator self, exvector::iterator other, exvector & v) const; + + // non-virtual functions in this class +protected: + void do_print(const print_context & c, unsigned level) const; + void do_print_latex(const print_latex & c, unsigned level) const; +}; + + /** This class represents the Dirac gamma Lorentz vector. */ -class diracgamma : public tensor +class diracgamma : public cliffordunit { - GINAC_DECLARE_REGISTERED_CLASS(diracgamma, tensor) + GINAC_DECLARE_REGISTERED_CLASS(diracgamma, cliffordunit) // functions overriding virtual functions from base classes public: @@ -98,12 +124,15 @@ protected: }; -/** This class represents the Dirac gamma5 object which anticommutes with +/** This class represents the Dirac gamma5 object which anticommutates with * all other gammas. */ class diracgamma5 : public tensor { GINAC_DECLARE_REGISTERED_CLASS(diracgamma5, tensor) + // functions overriding virtual functions from base classes + ex conjugate() const; + // non-virtual functions in this class protected: void do_print(const print_context & c, unsigned level) const; @@ -117,6 +146,9 @@ class diracgammaL : public tensor { GINAC_DECLARE_REGISTERED_CLASS(diracgammaL, tensor) + // functions overriding virtual functions from base classes + ex conjugate() const; + // non-virtual functions in this class protected: void do_print(const print_context & c, unsigned level) const; @@ -130,6 +162,9 @@ class diracgammaR : public tensor { GINAC_DECLARE_REGISTERED_CLASS(diracgammaR, tensor) + // functions overriding virtual functions from base classes + ex conjugate() const; + // non-virtual functions in this class protected: void do_print(const print_context & c, unsigned level) const; @@ -151,6 +186,14 @@ template<> inline bool is_exactly_a(const basic & obj) * @return newly constructed object */ ex dirac_ONE(unsigned char rl = 0); +/** Create a Clifford unit object. + * + * @param mu Index (must be of class varidx or a derived class) + * @param metr Metric (should be of class tensmetric or a derived class, or a symmetric matrix) + * @param rl Representation label + * @return newly constructed Clifford unit object */ +ex clifford_unit(const ex & mu, const ex & metr, unsigned char rl = 0); + /** Create a Dirac gamma object. * * @param mu Index (must be of class varidx or a derived class) @@ -199,6 +242,34 @@ ex dirac_trace(const ex & e, unsigned char rl = 0, const ex & trONE = 4); * to check two expressions for equality. */ ex canonicalize_clifford(const ex & e); +/** Automorphism of the Clifford algebra, simply changes signs of all + * clifford units. */ +ex clifford_prime(const ex & e); + +/** Main anti-automorphism of the Clifford algebra: makes reversion + * and changes signs of all clifford units. */ +inline ex clifford_bar(const ex & e) { return clifford_prime(e.conjugate()); } + +/** Reversion of the Clifford algebra, coincides with the conjugate(). */ +inline ex clifford_star(const ex & e) { return e.conjugate(); } + +ex delete_ONE(const ex &e); + +/** Calculation of the norm in the Clifford algebra. */ +ex clifford_norm(const ex & e); + +/** Calculation of the inverse in the Clifford algebra. */ +ex clifford_inverse(const ex & e); + +/** List or vector conversion into the Clifford vector. + * + * @param v List or vector of coordinates + * @param mu Index (must be of class varidx or a derived class) + * @param metr Metric (should be of class tensmetric or a derived class, or a symmetric matrix) + * @param rl Representation label + * @return Clifford vector with given components */ +ex lst_to_clifford(const ex & v, const ex & mu, const ex & metr, unsigned char rl = 0); + } // namespace GiNaC #endif // ndef __GINAC_CLIFFORD_H__