Would this experimental result actually be predicted by the quantum formalism, though? It sounds >like they had a setup similar to the double-slit experiment and found a small amount of interference >even when they measured which hole the particle traveled through, but I thought the quantum >formalism predicts that interference would be completely destroyed by such a measurement.
After googling, I found a power point presentation by John Cramer (creator of the transactional interpetation) at http://tinyurl.com/29atj which towards the bottom discusses Afshar's experiment and what it says about the various interpretations...this page claims that while the MWI and CI predict no interference, the transactional interpretation "Predicts interference, as does the QM formalism." So, it sounds like he really is claiming that the MWI predicts something different than the quantum formalism, which cannot be correct since the MWI is just the pure formalism (ie the deterministic rules for the evolution of a system's wavefunction over time) without the idea of the wavefunction being "collapsed" when the system is measured (the projection postulate).
Lose those love handles! MSN Fitness shows you two moves to slim your waist. http://fitness.msn.com/articles/feeds/article.aspx?dept=exercise&article=et_pv_030104_lovehandles