PDA

View Full Version : complex conjugate of a 5 x 5 matrices?


ayalam
Jun2-05, 06:21 PM
How do you do it?

matt grime
Jun3-05, 04:08 AM
To get the complex conjugate of any matrix you just conjugate each entry.

qqchico
Jun6-05, 06:49 PM
Sorry im doing something similar; converting a ket into a bra. wouldn't something change like order.

HallsofIvy
Jun6-05, 07:29 PM
matt grime is completely right for "complex conjugate". However, you may be intending "Hermitian conjugate" or "adjoint". To find the Hermitian conjugate (adjoint) of a complex matrix you take the complex conjugate of each entry and take the transpose: rows become columns.

qqchico
Jun6-05, 08:06 PM
Can i get a 5*5 matrices example

Nylex
Jun7-05, 01:00 AM
A = \left(\begin{array}{ccccc}0 & i & 3 & 2 & 1 - 2i \\ -i & 7 & 6 & 4 & 0 \\
3 + i & 2 & 0 & -2i & 4 \\ 9 & 1 & i & 8 & 1 \\ 0 & 0 & 0 & 7i & 0\end{array}\right) A^T = \left(\begin{array}{ccccc}0 & -i & 3 + i & 9 & 0 \\ i & 7 & 2 & 1 & 0 \\ 3 & 6 & 0 & i & 0 \\ 2 & 4 & -2i & 8 & 7i \\ 1 - 2i & 0 & 4 & 1 & 0\end{array}\right) A^\dagger = \left(\begin{array}{ccccc}0 & i & 3 - i & 9 & 0 \\ -i & 7 & 2 & 1 & 0 \\ 3 & 6 & 0 & -i & 0 \\ 2 & 4 & 2i & 8 & -7i \\ 1 + 2i & 0 & 4 & 1 & 0\end{array}\right)

I hope that's right and I've not made any mistakes.

HallsofIvy
Jun7-05, 10:27 AM
In Nylex's example, A^T is the transpose and A^{\dagger} is the Hermitian conjugate or adjoint.
Using the same example, the "complex conjugate" that was originally asked for, and matt grimes described, would be
A^* = \left(\begin{array}{ccccc}0 & -i & 3 & 2 & 1 + 2i \\ i & 7 & 6 & 4 & 0 \\3 - i & 2 & 0 & 2i & 4 \\ 9 & 1 & -i & 8 & 1 \\ 0 & 0 & 0 & -7i & 0\end{array}\right)

qqchico
Jun10-05, 03:12 AM
nice examples