Page 311 - Determinants and Their Applications in Mathematical Physics
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296   6. Applications of Determinants in Mathematical Physics

          where τ j is a function which appears in the Neugebauer solution and is
          defined in (6.2.20).

                                     (−1) j−1 M j (c)x r
                                   2n
                              w r =                 j  .           (6.10.27)
                                             ε ∗
                                   j=1        j
          Then,
                         x i − x j =  c i − c j  ,  independent of z,
                                     ρ
                                       2
                            ε j ε =1 + x .                         (6.10.28)
                               ∗
                               j       j
                   (m)
          Now, let H  (ε) denote the determinant of order 2n whose column vectors
                   2n
          are defined as follows:
                 (m)              2      m−1          2
               C    (ε)= ε j c j ε j c ε j ··· c  ε j 1 c j c ··· c 2n−m−1 T  ,
                                  j                   j
                 j                       j                j
                                                                  2n
                                     1 ≤ j ≤ 2n.                   (6.10.29)
          Hence,
                         
              m−1
                  	 
             2                            T
               (m)  1      1  c j  c j  c j        2    2n−m−1
             C         =            ···      1 c j c ··· c         (6.10.30)
                    ε     ε j  ε j  ε j  ε j
               j                                   j    j
                                                               2n
                          1       2    m−1           2     2n−m−1    T
                       =    1 c j c ··· c   ε j c j ε j c ε j ··· c   .
                                  j                  j            ε j
                                       j                   j
                                                                    2n
                         ε j
          But,
             (2n−m)              2     2n−m−1         2
           C      (ε)= ε j c j ε j c ε j ··· c  ε j 1 c j c ··· c m−1 T  . (6.10.31)
                                 j                    j
             j                         j                  j
                                                               2n
          The elements in the last column vector are a cyclic permutation of the
          elements in the previous column vector. Hence, applying Property (c(i))
          in Section 2.3.1 on the cyclic permutation of columns (or rows, as in this
          case),
                                                  −1
                         	 
                  2n
                      (m)  1         m(2n−1)            (2n−m)
                     H        =(−1)                 H       (ε),
                           ε
                      2n                        ε j     2n
                                             j=1
                     (n+1)          (n−1)
                   H      1/ε     H      (ε)
                    2n        = −   2n      .                      (6.10.32)
                      (n)            (n)
                    H    1/ε       H    (ε)
                     2n              2n
          Theorem.
                                  2 −m(m−1)/2
          a. |w i+j−2 + w i+j | m =(−ρ )    {V 2n (c)} m−1 H (m) (ε),
                                                      	  1  2n
                           2 −m(m−1)/2
          b. |w i+j−2 | m =(−ρ )      {V 2n (c)} m−1 H  (m)  .
                                                        ε
                                                   2n    ∗
          The determinants on the left are Hankelians.
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