LeviCivita.h File Reference

#include "Mint/LorentzMatrix.h"
#include "Mint/Utils.h"
#include "TLorentzVector.h"
#include "TMatrixT.h"

Go to the source code of this file.

Functions
double	LeviCivita (const TLorentzVector &p0, const TLorentzVector &p1, const TLorentzVector &p2, const TLorentzVector &p3)
double	LeviCivita (const TLorentzVector &p0, const TLorentzVector &p1, const LorentzMatrix &M)
TLorentzVector	LeviCivita (const TLorentzVector &a, const TLorentzVector &b, const TLorentzVector &c)

Function Documentation

LeviCivita() [1/3]

double LeviCivita ( const TLorentzVector &  p0, const TLorentzVector &  p1, const TLorentzVector &  p2, const TLorentzVector &  p3  )

inline

Definition at line 12 of file LeviCivita.h.

                                        {
  
  // it is the determinant of the matrix made up of p0, p1, p2, p3
  TMatrixT<double> m(4, 4);
  for(int i=0; i < 4; i++){
    // strange indexing, because I have 0th component = E
    // but Rene has 0th component = px, 3rd component = E:
    m(0, i)=p0[(i+3)%4];
    m(1, i)=p1[(i+3)%4];
    m(2, i)=p2[(i+3)%4];
    m(3, i)=p3[(i+3)%4];
  }
  return m.Determinant();
}

LeviCivita() [2/3]

double LeviCivita ( const TLorentzVector &  p0, const TLorentzVector &  p1, const LorentzMatrix &  M  )

inline

Definition at line 30 of file LeviCivita.h.

                                      {
  double sum=0;
  for(int a=0; a<4; a++){
    for(int b=0; b<4; b++){
      if(a==b) continue;
      for(int c=0; c<4; c++){
    if(a==c || b==c) continue;
    for(int d=0; d<4; d++){
      if(a==d || b==d || c==d) continue;
      sum += MINT::LeviCita(a, b, c, d)
        * p0[  (a + 3)%4 ] // coping with the stupid, stupid
        * p1[  (b + 3)%4 ] // stupid, stupid convention in TLorentzVector
        * M[ (c + 3)%4 ][ (d + 3)%4 ] // that index 0 = p_x, 1=py, 2=pz, 3=Energy
        ; // arrrrgh. ARRRRRRRGH!!! Rene!!! Why????
      // (0 + 3)%4 = 3, (1+3)%4 = 0, (2+3)%4 = 1 (3+3)%4 = 2
    }
      }
    }
  }
  return sum;
}

LeviCivita() [3/3]

TLorentzVector LeviCivita ( const TLorentzVector &  a, const TLorentzVector &  b, const TLorentzVector &  c  )

inline

Definition at line 54 of file LeviCivita.h.

                                                                                                           {
    
    TLorentzVector v;
    
    v.SetT( -1.* a.X() * ( b.Y() * c.Z() - b.Z() * c.Y() )
           - a.Y() * ( b.Z() * c.X() - b.X() * c.Z() )  
           - a.Z() * ( b.X() * c.Y() - b.Y() * c.X() ) );
    
    v.SetZ(  a.X() * ( b.T() * c.Y() - b.Y() * c.T() )
           + a.Y() * ( b.X() * c.T() - b.T() * c.X() )  
           + a.T() * ( b.Y() * c.X() - b.X() * c.Y() ) );
    
    v.SetY(  a.X() * ( b.Z() * c.T() - b.T() * c.Z() )
           + a.Z() * ( b.T() * c.X() - b.X() * c.T() )  
           + a.T() * ( b.X() * c.Z() - b.Z() * c.X() ) );
    
    v.SetX(  a.Y() * ( b.T() * c.Z() - b.Z() * c.T() )
           + a.Z() * ( b.Y() * c.T() - b.T() * c.Y() )  
           + a.T() * ( b.Z() * c.Y() - b.Y() * c.Z() ) );

    return  v;
}