Violation of Bohr's Complementarity: One Slit or Both?

We have implemented a novel double-slit "which-way" experiment which raises interesting questions of interpretation. Coherent laser light is passed through a converging lens and then through a dual pinhole producing two beams crossing over at the focal point of the lens, and fully separating further downstream providing which-way information. A thin wire is then placed at a minimum of the interference pattern formed at the cross-over region. No significant reduction in the total flux or resolution of the separated beams is found, providing evidence for coexistence of perfect interference and which-way information in the same experiment, contrary to the common readings of Bohr's principle of complementarity. This result further supports the conclusions of the original experiment by the author in which an imaging lens was employed to obtain which-way information. Finally, a short discussion of the novel non-perturbative measurement technique for ensemble properties is offered.Comment: 6 pages, 4 figures, Vaxjo University Conference, QUANTUM THEORY: Reconsideration of Foundations - 3, January 4, 200

The Power of An Outside Option that Generates a Focal Point: An Experimental Investigation

Existing experimental studies have shown that an outside option, when offered to one of the two players who later participate in a battle-of-the-sexes game, facilitates coordination by making the equilibrium that favors the same player focal. Since the other player’s payoff in the outside option was lower than that in the focal point, it is possible that there was a reciprocal motive of the other player to coordinate on the focal point. Then it is possible that the actual power of the outside option to generate the focal point was either lower or non-existent. The current paper reports results of an experiment designed to test for the focal point effect of the outside option by controlling for the reciprocal motive of the other player. The results confirm that the outside option can generate the focal point even when the reciprocal motive is absent. In fact, the saliency of the focal point is higher after controlling for reciprocity.

The Role of Intracellular Interactions in the Collective Polarization of Tissues and its Interplay with Cellular Geometry

Planar cell polarity (PCP), the coherent in-plane polarization of a tissue on multicellular length scales, provides directional information that guides a multitude of developmental processes at cellular and tissue levels. While it is manifest that cells utilize both intracellular and intercellular mechanisms, how the two produce the collective polarization remains an active area of investigation. We study the role of intracellular interactions in the large-scale spatial coherence of cell polarities, and scrutinize the role of intracellular interactions in the emergence of tissue-wide polarization. We demonstrate that nonlocal cytoplasmic interactions are necessary and sufficient for the robust long-range polarization, and are essential to the faithful detection of weak directional signals. In the presence of nonlocal interactions, signatures of geometrical information in tissue polarity become manifest. We investigate the deleterious effects of geometric disorder, and determine conditions on the cytoplasmic interactions that guarantee the stability of polarization. These conditions get progressively more stringent upon increasing the geometric disorder. Another situation where the role of geometrical information might be evident is elongated tissues. Strikingly, our model recapitulates an observed influence of tissue elongation on the orientation of polarity. Eventually, we introduce three classes of mutants: lack of membrane proteins, cytoplasmic proteins, and local geometrical irregularities. We adopt core-PCP as a model pathway, and interpret the model parameters accordingly, through comparing the in silico and in vivo phenotypes. This comparison helps us shed light on the roles of the cytoplasmic proteins in cell-cell communication, and make predictions regarding the cooperation of cytoplasmic and membrane proteins in long-range polarization.Comment: 15 pages Main Text + 8 page Appendi