X-Message-Number: 16169 From: Transoniq <> Subject: Abstractionists.... Date: Tue, 1 May 101 16:14:51 -0700 (PDT) The April 6 *Science* had a review of *Quantum Computation and Quantum Information* which contained a paragraph which might (hopefully) give the Abstractionists pause: Jumping to chapter 12 ("Quantum information theory"), we find ourselves confronted by strange limits with respect to accessible information about quantum states. "Not only are quantum states impossible to copy, but they also cannot be perfectly distinguished." We are then led to contemplate reality. Although the description of the state, being classical, can be copied and distinguished at will, the actual referent of that description cannot. This is why a classical simulation of a quantum system, even if perfect in terms of the underlying equations, cannot substitute for the behavior of the real thing." In our scientific training we are always warned against mistaking a description of reality for the reality itself. Nevertheless, it comes as a surprise to see how technically relevant this warning can be. Well, he probably would not have been surprised had he been on this list... Eric Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=16169