Page 180 - Intro to Tensor Calculus
P. 180

175








                             VECTOR                  GENERAL TENSOR               CARTESIAN TENSOR


                                                            i
                                         ~
                                         A                 A or A i                               A i
                                     ~ ~
                                                      i
                                                                 j
                                                               i
                                     A · B          A B i = g ij A B = A i B i                  A i B i
                                                      i      ij
                                                     A B i = g A i B j
                                                             1  ijk
                                    ~
                                        ~
                                                        i
                                ~
                                C = A × B              C = √ e    A j B k              C i = e ijk A j B k
                                                              g
                                                                                                 ∂Φ
                                                             im
                               ∇ Φ = grad Φ                 g  Φ ,m                        Φ ,i =
                                                                                                 ∂x i
                                                                 1   ∂  √    r                  ∂A i
                                         ~
                                                 mn
                                                            r
                                  ~
                               ∇· A = div A     g  A m,n = A  ,r  = √   ( gA )            A i,i =
                                                                  g ∂x r                         ∂x i
                                         ~
                                ~
                            ~
                                                           i
                        ∇× A = C =curl A                 C =   ijk  A k,j                C i = e ijk  ∂A k
                                                                                                 ∂x j
                                                            1  ∂    √  ij  ∂U              ∂    ∂U
                                                 mn
                                        2
                                      ∇ U       g   U ,mn = √        gg
                                                             g ∂x j      ∂x i             ∂x i  ∂x i
                                                               m
                                                          i
                                         ~
                                    ~
                               ~
                              C =(A ·∇)B                 C = A B  i                             ∂B i
                                                                   ,m                   C i = A m  m
                                                                                                ∂x
                                  ~
                              ~
                                                           i
                                                                i
                                        ~
                              C = A(∇· B)                 C = A B j ,j                  C i = A i  ∂B m
                                                                                                ∂x m
                                                                                          ∂     ∂A i
                                        2 ~
                                  ~
                                                                        jm
                                                     jm
                                                 i
                                                         i
                                  C = ∇ A      C = g   A  ,mj  or C i = g  A i,mj  C i =
                                                                                        ∂x m   ∂x m
                                                            im  i
                                   ~
                                   A ·∇ φ                  g  A φ ,m                            A i φ ,i
                                                                                                2
                                                                                               ∂ A r
                                       ~
                                 ∇ ∇· A                   g im  A r
                                                                ,r ,m
                                                                                              ∂x i ∂x r
                                                                                       2        2
                                                                                      ∂ A j    ∂ A i
                                        ~
                              ∇× ∇× A                   ijk g jm    kst  A t,s              −
                                                                      ,m
                                                                                     ∂x j ∂x i  ∂x j ∂x j
                                            Table 1 Vector and tensor representations.
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