Please Compute Concurrence Whats wrong

[coffekreizy]

Please Compute Concurrence...Whats wrong!

I have this rho matrix:

rho=[0.001 0 0 0.125;0 0.499 -0.374 0;0 -0.374 0.499 0;0.125 0 0 0.001];


Why the concurrence is different if you compute numerically (you can download programs for compute the concurrence in this sites:
http://optics.szfki.kfki.hu/~toth/qubit4matlab.html
http://www.dr-qubit.org/matlab.php

And if you use the Ec. 26 of Eberly paper/ Optics comm 264 (2006) 393-397

 

[haushofer]

I'm afraid you'll have to put a little more effort in your post if you expect people to help you.