Quantum Bit Commitment with a Composite Evidence

Entanglement-based attacks, which are subtle and powerful, are usually believed to render quantum bit commitment insecure. We point out that the no-go argument leading to this view implicitly assumes the evidence-of-commitment to be a monolithic quantum system. We argue that more general evidence structures, allowing for a composite, hybrid (classical-quantum) evidence, conduce to improved security. In particular, we present and prove the security of the following protocol: Bob sends Alice an anonymous state. She inscribes her commitment $b$ by measuring part of it in the + (for $b = 0$) or $\times$ (for $b=1$) basis. She then communicates to him the (classical) measurement outcome $R_x$ and the part-measured anonymous state interpolated into other, randomly prepared qubits as her evidence-of-commitment.Comment: 6 pages, minor changes, journal reference adde

Some empirical evidences on ASEAN 5 fiscal policy regime and monetary and fiscal policy interactions

The interest of common currency among Asian countries have spurred many events happening for the past few years, notably the declaration of Asian Currency Unit in 2006 by Asia Development Bank (ADB). Hence, research papers examining on the integration of monetary policies are abundance. However, paper on examining fiscal policy regime and interaction between monetary and fiscal policy on ASEAN countries, is lacking. The success of monetary union relies on the price stability of member nations. However, joining a monetary union means the lost of monetary policy sovereignty. Therefore, fiscal policy turns to be the next important tool to maintain price stability. This is reflected from the EMU countries after year 1999, where national monetary policies are completely centralized to the European Central Bank (ECB). The European System of Central Banks (ESCB) combines unity of decisions with participation of national central banks in the decision making process and implementation. Nevertheless, national fiscal policies of the member countries are still in the hands of the national governments. This paper intents to examine the type of fiscal policy regime practiced by ASEAN 5 countries. Using macro-economic data for Indonesia, Malaysia, Philippines, Singapore and Thailand, the interrelationship of government surplus/deficits and liabilities is analyzed using Correlation test, Vector Auto-regression (VAR) and Impulse response (IR) function to determine whether a Ricardian or Non-Ricardian fiscal policy has been implemented. Also, comparison of monetary and fiscal policy interactions between some EMU countries and ASEAN 5 are made. The results indicate interactions among inter EMU countries and inter ASEAN countries are generally comparable

Heuristic bidding strategies for multiple heterogeneous auctions

This paper investigates utility maximising bidding heuristics for agents that participate in multiple heterogeneous auctions, in which the auction format and the starting and closing times can be different. Our strategy allows an agent to procure one or more items and to participate in any number of auctions. For this case, forming an optimal bidding strategy by global utility maximisation is computationally intractable, and so we develop two-stage heuristics that first provide reasonable bidding thresholds with simple strategies before deciding which auctions to participate in. The proposed approach leads to an average gain of at least 24% in agent utility over commonly used benchmarks

The role of a pressure-dependent rheology in the dynamics of mantle circulation

A thermomechanical model for upper mantle convection was constructed such that the thickness and the structure of the lithosphere are determined self consistently by the heat transported by convection. In this study of the interaction between the lithosphere and upper mantle, strongly temperature and pressure dependent rheologies for both Newtonian and non-Newtonian creep mechanisms are employed. For a strictly temperature dependent rheology an insignificant amount of heat, less than 12.5 mW/sq m, can be transported convectively for an interior viscosity, 0(10 sup 21 Pas), compatible with post glacial rebound. On the other hand, for similar values of the interior viscosity, steady heat fluxes between 20 and 40 mW/sq m are produced by introducing pressure dependence into the rheology. For the temperature and pressure dependent flow law the horizontally averaged interior temperature displays very little variation with the amount of heat evacuated, once all of the rheological parameters are fixed. This finding may have important ramifications for parameterized convection