Status of electroweak phase transition and baryogenesis

I review recent progress on the electroweak phase transition and baryogenesis, focusing on the minimal supersymmetric Standard Model as the source of new physics.     

Quantum,classical and intermediate: An illustrative example

We present a model that allows one to build structures that evolve continuously from classical to quantum, and we study the intermediate situations, giving rise to structures that are neither classical nor quantum. We construct the closure structure corresponding to the collection of eigenstate sets of these intermediate situations, and demonstrate how the superposition principle disappears during the transition from quantum to classical. We investigate the validity of the axioms of quantum mechanics for the intermediate situations.     

The Hidden Measurement Formalism: What Can Be Explained and Where Quantum Paradoxes Remain

In the hidden measurement formalism that we havedeveloped in Brussels we explain quantum structure asdue to the presence of two effects; (a) a real change ofstate of the system under influence of the measurement and (b) a lack of knowledge abouta deeper deterministic reality of the measurementprocess. We show that the presence of these two effectsleads to the major part of the quantum mechanical structure of a theory describing a physicalsystem, where the measurements to test the properties ofthis physical system contain the two mentioned effects.We present a quantum machine, with which we can illustrate in a simple way how the quantumstructure arises as a consequence of the two effects. Weintroduce a parameter that measures the amount of lackof knowledge on the measurement process, and by varying this parameter, we describe acontinuous evolution from a quantum structure (maximallack of knowledge) to a classical structure (zero lackof knowledge). We show that for intermediate values of we find a new type of structure that isneither quantum nor classical. We analyze the quantumparadoxes in the light of these findings and show thatthey can be divided into two groups: (1) The group(measurement problem and Schrodinger cat paradox) where theparadoxical aspects arise mainly from the application ofstandard quantum theory as a general theory (e.g., alsodescribing the measurement apparatus). This type of paradox disappears in the hiddenmeasurement formalism. (2) A second group collecting theparadoxes connected to the effect of nonlocality (theEinstein-Podolsky-Rosen paradox and the violation of Bell's inequalities). We show that theseparadoxes are internally resolved because the effect ofnonlocality turns out to be a fundamental property ofthe hidden-measurement formalism itself.     

Synthesis and evaluation of dimeric lipophilic iminosugars as inhibitors of glucosylceramide metabolism

Four dimeric and four monomeric lipophilic iminosugars were synthesized and subsequently evaluated on their inhibitory potential towards mammalian glucosylceramide synthase, glucocerebrosidase, β-glucosidase 2, sucrase and lysosomal α-glucosidase. Compared to their monomeric counterparts the dimeric inhibitors showed decreased inhibition of glucosylceramide synthase and generally a comparable inhibitory potency for the glycosidases.     

Synthesis,Structure and Photophysical Properties of a New Class of Inherently Chiral Boron(III) Chelates—The tert-Leucine Complexes

A new family of boron(III) chelates is introduced whereby molecular chirality, confirmed by circular dichroism, is imported during synthesis such that isolation of the diastereoisomers does not require separation procedures. The photophysical properties of two members of the family have been examined: the N,O,O-salicylaldehyde-based derivative shows pronounced intramolecular charge-transfer character in fluid solution and is weakly fluorescent, with a large Stokes shift. The corresponding 2-methylamino-benzaldehyde-derived N,N,O-chelate absorbs and fluoresces in the visible region with a much smaller Stokes shift. Orange fluorescence is also observed for this compound as a cast film. Temperature-dependence studies show that decay of the fluorescent state is weakly activated but emission is less than quantitative at 77 K. Quite rare for boron(III)-based chelates, this derivative undergoes intersystem crossing to form a meta-stable triplet-excited state. X-ray crystal structures are reported for both compounds, along with simulated ECD spectra.