Acculturation in a Transcultural World

From a nationalist perspective, each nation possesses a distinct culture which is said to be homogeneous and separate from the cultures of all other nations. Accordingly, acculturation of migrants and their descendants occurs when they gradually move away from the country of origin's culture and assimilate to the culture of the country of immigration. This perspective, however, is empirically inaccurate: With regard to languages, religions, and ethical values, there are not only differences between nations, but also differences within them and cross-country cultural commonalities. Thus, as Wolfgang Welsch argues, we live in a transcultural world, and acculturation is problematized in two ways: Migrants do not need to be culturally different from the people in the country of immigration, and that country does not need to possess a common, homogeneous national culture. Yet both problems can be overcome if the idea of distinct national cultures is replaced by the concept of national, cultural mainstreams which, following Alba and Nee and the ethnic boundary making approach, are socially constructed and characterized by intersubjective associations between nations and cultural elements. Such mainstreams do not need to be separate and homogeneous and are thus compatible with transculturality. Acculturation can then be reconceptualized as one of three possible pathways of integration into the cultural mainstream of the country of immigration

Single-Quadrature Continuous-Variable Quantum Key Distribution

Most continuous-variable quantum key distribution schemes are based on the Gaussian modulation of coherent states followed by continuous quadrature detection using homodyne detectors. In all previous schemes, the Gaussian modulation has been carried out in conjugate quadratures thus requiring two independent modulators for their implementations. Here, we propose and experimentally test a largely simplified scheme in which the Gaussian modulation is performed in a single quadrature. The scheme is shown to be asymptotically secure against collective attacks, and considers asymmetric preparation and excess noise. A single-quadrature modulation approach renders the need for a costly amplitude modulator unnecessary, and thus facilitates commercialization of continuous-variable quantum key distribution.Comment: 13 pages, 7 figure

Continuous Variable Quantum Key Distribution with a Noisy Laser

Existing experimental implementations of continuous-variable quantum key distribution require shot-noise limited operation, achieved with shot-noise limited lasers. However, loosening this requirement on the laser source would allow for cheaper, potentially integrated systems. Here, we implement a theoretically proposed prepare-and-measure continuous-variable protocol and experimentally demonstrate the robustness of it against preparation noise stemming for instance from technical laser noise. Provided that direct reconciliation techniques are used in the post-processing we show that for small distances large amounts of preparation noise can be tolerated in contrast to reverse reconciliation where the key rate quickly drops to zero. Our experiment thereby demonstrates that quantum key distribution with non-shot-noise limited laser diodes might be feasible.Comment: 10 pages, 6 figures. Corrected plots for reverse reconciliatio

Super sensitivity and super resolution with quantum teleportation

We propose a method for quantum enhanced phase estimation based on continuous variable (CV) quantum teleportation. The phase shift probed by a coherent state can be enhanced by repeatedly teleporting the state back to interact with the phase shift again using a supply of two-mode squeezed vacuum states. In this way, both super resolution and super sensitivity can be obtained due to the coherent addition of the phase shift. The protocol enables Heisenberg limited sensitivity and super- resolution given sufficiently strong squeezing. The proposed method could be implemented with current or near-term technology of CV teleportation.Comment: 5 pagers, 3 figure

Die diskursive Konstruktion des Flüchtlings

Die Frage "Wer ist ein Flüchtling?" lässt sich auf zwei verschiedene Weisen beantworten: Eine realistische Perspektive geht davon aus, dass Menschen durch ihre Flucht infolge bestimmter Fluchtursachen zu Flüchtlingen werden und Sprache diese Tatsache abbildet. Demgegenüber weist die Perspektive der diskursiven Konstruktion des Flüchtlings Sprache und Diskursen eine produktive Funktion bei der Konstruktion von Flüchtlings-Subjekten zu. Zuvorderst wird die Kategorie 'Flüchtling' in politischen, medialen, wissenschaftlichen und anderen Diskursen hervorgebracht und mal enger, mal weiter definiert. Durch solche Prozesse entscheidet sich, ob Subjekte als Flüchtlinge oder vielmehr etwa als Migrant*innen, Asylbewerber*innen oder Binnenvertriebene kategorisiert werden. Darüber hinaus ermöglichen diskursive Bedeutungsstrukturen die klassifizierende Unterscheidung u. a. von Flüchtlingen unterschiedlicher Nationalität, Religionszugehörigkeit oder Geschlechtsidentität. Subjektpositionen, die Flüchtlingen in Diskursen zugewiesen werden, charakterisieren diese häufig, aber nicht ausschließlich, als Opfer oder Bedrohung. Und Regeln des Zugangs zu Sprecher*innen-Positionen in verschiedenen Diskursfeldern beeinflussen, inwiefern Flüchtlinge selbst in über sie geführten Diskursen zu Wort kommen. Für die soziologische Erforschung der diskursiven Konstruktion des Flüchtlings bietet das Forschungsprogramm der Wissenssoziologischen Diskursanalyse hilfreiche Anregungen. Angesichts des einstweilen bestehenden Mangels an Forschungen zu Diskursen über Flüchtlinge im globalen Süden anzuraten, wenn auch mit besonderen Herausforderungen verknüpft, ist interkulturelle Diskursforschung