Quantum Paradoxes || Quantum Measurements and Relativity

✍ Scribed by Aharonov, Yakir; Rohrlich, Daniel

• Publisher: Wiley-VCH Verlag GmbH
• Year: 2005
• Tongue: German
• Weight: 297 KB
• Edition: New Edition
• Category: Article
• ISBN: 3527403914
• DOI: 10.1002/9783527619115.ch14

✦ Synopsis

Previous chapters discuss nonrelativistic quantum mechanics. Is there a relativistic quantum mechanics? In this chapter we assume that there is -and arrive at a paradox. The paradox concerns Lorentz transformations of quantum measurements. At the end of a quantum measurement, an entangled state of the measured system and measuring device collapses to a product state, according to von Neumann. (See Chap. 9.) The collapse is not Lorentz invariant, so we try to make it Lorentz invariant. The paradox is that there seems to be no way to make collapse Lorentz invariant.

The paradox concerns the collapse, not the correlations, of entangled states. If Alice and Bob make local measurements, their results are Lorentz invariant, and the correlations in their results are Lorentz invariant, as well. Bell's inequality and Eq. (3.12) do not depend on how we resolve the paradox of Sect. 14.1; nonlocal quantum correlations are nonlocal in any inertial reference frame.