December 2009 - ITP-quantumseminare

[QI] QI Seminar
by Dejan D. Dukaric 21 Dec '09

21 Dec '09

Dear All, This weeks research day on Tuesday will be at the Computer Science Building where Sandro will present his Semester Thesis supervised by Esther. Speaker: Sandro Coretti Title: Tripartite non-local correlations Time: 5 pm Place: IFW E42 Cheers, Dejan

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[QI] QI Seminar
by Dejan D. Dukaric 15 Dec '09

15 Dec '09

Dear All, Speaker: Dejan Dukaric Title: Tensor norms Time: 5 pm Place: HIT K51 Abstract: I will give an introduction to tensor norms and how one can use these norms in order to define different state spaces. Cheers, Dejan

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[QI] QI Seminar
by Dejan D. Dukaric 15 Dec '09

15 Dec '09

Dear All, Speaker: Dejan Dukaric Title: Tensor norms Time: 5 pm Place: HIT K51 Abstract: I will give an introduction to tensor norms and how one can use these norms in order to define different state spaces. Cheers, Dejan

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no research day this week
by Stefan Hengl 14 Dec '09

14 Dec '09

Hi all, there will be no talk this week. Cheers, Stefan -- ETH Zurich Stefan Hengl Institute for Theoretical Physics Wolfgang-Pauli-Strasse 27, HIT K 31.6 8093 Zurich Switzerland Tel. +41 (0)44 633 7036 Email: hengl(a)itp.phys.ethz.ch

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[QI] QI Seminar
by severin winkler 07 Dec '09

07 Dec '09

Speaker: Severin Winkler Title: "Statistical Impossibility Results for Oblivious Transfer Reductions" Time: 5 pm Place: IFW E44 The talk presents results from a project with Juerg Wullschleger on lower bounds for information-theoretically secure implementations of oblivious transfer in the statistical case (title and abstract below). Some familiarity with concepts from secure two-party computation is assumed - and there is no relation to quantum information theory :( . Title: Statistical Impossibility Results for Oblivious Transfer Reductions Abstract: Due to its universality oblivious transfer (OT) is a primitive of great importance in secure multi-party computation. OT is impossible to implement from scratch in an unconditionally secure way, but there are many reductions of OT to other variants of OT, as well as other primitives such as noisy channels. It is important to know how efficient such unconditionally secure reductions can be in principle, i.e., how many instances of a given primitive are at least needed to implement OT. For perfect (error-free) implementations good lower bounds are known, e.g. the bounds by Beaver (STOC '96) or by Dodis and Micali (EUROCRYPT '99). But since in practice one is usually willing to tolerate a small probability of error, and since these statistical reductions can be much more efficient, the known bounds have only limited application. In this work we provide lower bounds on the efficiency of 1-out-of-n OT and Rabin-OT reductions to distributed randomness in the statistical case. From these results we derive bounds on reductions to different variants of OT that generalize known bounds to the statistical case. Our bounds hold in particular for transformations between a finite number of primitives and for any error.

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room update
by Forster Manuel 01 Dec '09

01 Dec '09

Dear all, Note an update of today's talk location. Speaker: Manuel Forster Title: Towards identifying a universal unit of nonlocality Time: 5 pm Place: IFW D 42 Abstract: As a universal unit of nonlocality we understand a system allowing the construction of non-interactive protocols to simulate any nonsignaling system. Could such a unit be bipartite? The answer is no - for example no bipartite system can simulate correlations arising from measurements on a five-qubit cluster state. I will explain Barrett and Pironio's nice and simple proof of this statement. Best regards. Manuel

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[QI] QI Seminar
by Dejan D. Dukaric 01 Dec '09

01 Dec '09

Dear All, Speaker: Manuel Forster Title: Towards identifying a universal unit of nonlocality Time: 5 pm Place: HIT K51 Abstract: As a universal unit of nonlocality we understand a system allowing the construction of non-interactive protocols to simulate any nonsignaling system. Could such a unit be bipartite? The answer is no - for example no bipartite system can simulate correlations arising from measurements on a five-qubit cluster state. I will explain Barrett and Pironio's nice and simple proof of this statement. Cheers, Dejan

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[QI] QI Seminar
by Dejan D. Dukaric 01 Dec '09

01 Dec '09

Dear All, Speaker: Manuel Forster Title: TBA Time: 5 pm Place: HIT K51 Cheers, Dejan

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