Topological Factors Derived from Bohmian Mechanics

We derive for Bohmian mechanics topological factors for quantum systems with a multiply-connected configuration space $$ \mathcal{Q}. $$ These include nonabelian factors corresponding to what we call holonomy-twisted representations of the fundamental group of $$ \mathcal{Q}. $$ We employ wave functions on the universal covering space of $$ \mathcal{Q}. $$ As a byproduct of our analysis, we obtain an explanation, within the framework of Bohmian mechanics, of the fact that the wave function of a system of identical particles is either symmetric or anti-symmetric. Communicated by Yosi Avron Submitted: 21/06/2005 Revised: 10/01/2006 Accepted: 27/01/2006     

Selective nucleophilic replacement of the benzylsulfanyl group in 2,4‐disulfanyl‐substituted thieno[2,3‐d]pyrimidin‐6‐carboxylic acid derivatives by secondary amines

Thieno[2,3‐d]pyrimidines with benzylsulfanyl and allylsulfanyl group in the presence of other alkylsul‐fanyl substituents react selectively under mild conditions with secondary amines under replacement of the benzyl or allyl residue whereas the other substituents remain intact. This enables the synthesis of different basic substituted derivatives with potentially biologically activity.     

A global equilibrium as the foundation of quantum randomness

We analyze the origin of quantum randomness within the framework of a completely deterministic theory of particle motion—Bohmian mechanics. We show that a universe governed by this mechanics evolves in such a way as to give rise to the appearance of randomness, with empirical distributions in agreement with the predictions of the quantum formalism. Crucial ingredients in our analysis are the concept of the effective wave function of a subsystem and that of a random system. The latter is a notion of interest in its own right and is relevant to any discussion of the role of probability in a deterministic universe.Research supported in part by NSF Grant DMS-9105661.     

Über vollständige Normtopologien in linearen Räumen

Ohne Zusammenfassung     

Permethylcyclohexane

Permethylcyclohexane 2 has been synthesized and investigated by dynamic NMR spectroscopy. An unexpectedly low barrier (ΔG3₃₃₃ = 70.0 kJ/mol) of its chair-to-chair interconversion was found.