The Chemistry Maths Book, Second Edition

(Grace) #1

552 Chapter 19The matrix eigenvalue problem


The Hermitian conjugate matrix A



The Hermitian conjugate of Ais the transpose of the complex conjugate,


A



1 = 1 (A*)


T

1 = 1 (A


T

)* (19.53)


Thus, for order 3,


The Hermitian conjugate is also called the conjugate transpose matrix, the associate


matrix, and (in quantum mechanics) the adjoint matrix (not to be confused with the


matrix of the same name discussed in Section 18.4).


EXAMPLE 19.16Find the Hermitian conjugate of the matrix


The complex conjugateA*and Hermitian conjugateA



are


0 Exercises 36–38


The Hermitian conjugate plays the same role for complex matrices as does the


transpose for real matrices. For example, the inner (scalar) product of two vectors


a 1 = 1 (a


1

,a


2

,a


3

)andb 1 = 1 (b


1

,b


2

,b


3

) in a complex vector space is defined as (compare


equation (18.62))


ab (19.54)
·

==




















ab



()aaa


b


b


b


123

1

2

3

*** ==++ab ab ab


11 22 33



AA


*
=

−−−


+−










,=


−+



3231


12 2 2


312


23


ii


ii


ii


i



22


−− 12














i


A=


++−











3231


12 2 2


ii


ii


if A=














aaa


aaa


aaa


11
12 13

21 22 23

31 32 33








then A =











aaa


aaa


aa


11 21 31

12 22 32

13 223 33

**a





















Free download pdf