Talk:Bures metric

Fubini-Study metric

OK, If I squint my eyes a little bit, it seems to me that the Bures metric is just the Fubini-Study metric, written with a mixed state instead of a pure state. Right? I haven't checked the math yet...I'll try to, soon. linas (talk) 19:41, 13 July 2012 (UTC)

Yeah, I didn't check, but I did read the reference phys rev lett article which says as much. Wow. linas (talk) 20:25, 13 July 2012 (UTC)

What is d?

In the definition

$[d(\rho ,\rho +d\rho )]^{2}={\frac {1}{2}}{\mbox{tr}}(d\rho G),$

it is not clear, what $d$ is supposed to be. Needs some clarification. 195.37.234.74 (talk) 11:30, 12 July 2016 (UTC)

this article gives a false result for Bures distance between two orthogonal pure states

The article states that D_B(1,2) = pi/2 for rho_1 = |1><1| and rho_2 = |2><2| and <1|2>= 0 Clearly D_B = sqrt 2 not pi/2, from the definitions in the text. 140.180.240.67 (talk) 17:48, 25 March 2024 (UTC)

clarification: sqrt 2 is the direct Bures distance, pi/2 is the length of the geodesic (norm-preserving) path connecting them. Fixed in text