Quantum-proof randomness extractors via operator space theory

Quantum-proof randomness extractors are an important building block for classical and quantum cryptography as well as device independent randomness amplification and expansion. Furthermore they are also a useful tool in quantum Shannon theory. It is known that some extractor constructions are quantum-proof whereas others are provably not [Gavinsky et al., STOC'07]. We argue that the theory of operator spaces offers a natural framework for studying to what extent extractors are secure against quantum adversaries: we first phrase the definition of extractors as a bounded norm condition between normed spaces, and then show that the presence of quantum adversaries corresponds to a completely bounded norm condition between operator spaces. From this we show that very high min-entropy extractors as well as extractors with small output are always (approximately) quantum-proof. We also study a generalization of extractors called randomness condensers. We phrase the definition of condensers as a bounded norm condition and the definition of quantum-proof condensers as a completely bounded norm condition. Seeing condensers as bipartite graphs, we then find that the bounded norm condition corresponds to an instance of a well studied combinatorial problem, called bipartite densest subgraph. Furthermore, using the characterization in terms of operator spaces, we can associate to any condenser a Bell inequality (two-player game) such that classical and quantum strategies are in one-to-one correspondence with classical and quantum attacks on the condenser. Hence, we get for every quantum-proof condenser (which includes in particular quantum-proof extractors) a Bell inequality that can not be violated by quantum mechanics.Comment: v3: 34 pages, published versio

Variations on Classical and Quantum Extractors

Many constructions of randomness extractors are known to work in the presence of quantum side information, but there also exist extractors which do not [Gavinsky {\it et al.}, STOC'07]. Here we find that spectral extractors $\psi$ with a bound on the second largest eigenvalue $\lambda_{2}(\psi^{\dagger}\circ\psi)$ are quantum-proof. We then discuss fully quantum extractors and call constructions that also work in the presence of quantum correlations decoupling. As in the classical case we show that spectral extractors are decoupling. The drawback of classical and quantum spectral extractors is that they always have a long seed, whereas there exist classical extractors with exponentially smaller seed size. For the quantum case, we show that there exists an extractor with extremely short seed size $d=O(\log(1/\epsilon))$, where $\epsilon>0$ denotes the quality of the randomness. In contrast to the classical case this is independent of the input size and min-entropy and matches the simple lower bound $d\geq\log(1/\epsilon)$.Comment: 7 pages, slightly enhanced IEEE ISIT submission including all the proof

Islam dan Kebudayaan Melayu di Era Globalisasi di Malaysia

Sejarah telah menunjukkan bahwa dunia Melayu-Islam merupakan pusat peradaban, pusat perkembangan budaya dan pusat perdagangan yang penting. Kebudayaan Melayu-Islam sejak ratusan tahun telah memperlihatkan kemampuannya untuk berkembang pesat merangkumi bahasa, kesusasteraan, kesenian, pemikiran, dan norma hidup. memang tidak dapat dinafikan bahwa fenomena globalisasi memberikan pengaruh kepada kehidupan umat Melayu-Islam. Namun, pengaruhnya lebih cenderung kepada negatif berbanding positif. Cuma ia bergantung kepada umat Islam untuk mendepaninya dengan berpegang kepada ajaran Islam yang sebenar dengan berpaksikan kepada al-Qur'an dan al-Hadits. Pegangan yang kukuh dan utuh terhadap dua sumber Perundangan ini mampu menyelamatkan umat manusia khususnya umat Islam daripada terjerumus ke dalam kemungkaran yang tjidak dituntut dalam syariat Isla

I am the melting pot: Multiple identity integration among gay/bisexual/questioning male ethnic minority adolescents

For adolescents who belong to multiple minority groups, such as those who are ethnic and sexual minorities, they must develop both their ethnic and sexual identities as they develop their overall identity (Chung & Katayama, 1998). The goal of this study was to examine the ways in which ethnic and sexual minority male adolescents integrate their multiple identities, and to examine how their presentation of their identities changes depending on context. Because of the various types of data collected for each participant, a case study analysis (Yin, 1981) was employed to determine the themes and differences across participants and within each participant. The data that composed each individual participant’s case included the quantitative survey, the qualitative interview, and the Man Drawings. The results indicated that the youth in the study were able to integrate their multiple identities into their larger self-concept in spite of the various barriers to identity integration in all the communities in which they interacted. However, this was not completed without significant effort, as the participants indicated that they were developing their sense of ethnic, sexual, and gender identities at the time of data collection. The results indicated that the youth were able to develop a complex sense of self despite the presence of both positive and negative messages maintained by elements of all the communities of their membership. This process was further complicated because these identities were still under development during the integration process. Despite these challenges, the youth were able to integrate the many parts of themselves into one larger cohesive self-concept. Concerning the presentation of these multiple identities, the youth also engaged in a creative process to avoid the negative elements within their multiple communities by managing the expression of particular identities while participating in various aspects of their communities. The youth were adept in understanding the level of acceptance concerning their identities, and managed their behaviors to either minimize or enhance the visibility of particular aspects of themselves. Similar to the process of identity integration, the ways in which youth presented their identities was unique to the individual and their circumstances

Global existence and exponential decay for hyperbolic dissipative relativistic fluid theories

We consider dissipative relativistic fluid theories on a fixed flat, compact, globally hyperbolic, Lorentzian manifold. We prove that for all initial data in a small enough neighborhood of the equilibrium states (in an appropriate Sobolev norm), the solutions evolve smoothly in time forever and decay exponentially to some, in general undetermined, equilibrium state. To prove this, three conditions are imposed on these theories. The first condition requires the system of equations to be symmetric hyperbolic, a fundamental requisite to have a well posed and physically consistent initial value formulation. The second condition is a generic consequence of the entropy law, and is imposed on the non principal part of the equations. The third condition is imposed on the principal part of the equations and it implies that the dissipation affects all the fields of the theory. With these requirements we prove that all the eigenvalues of the symbol associated to the system of equations of the fluid theory have strictly negative real parts, which in fact, is an alternative characterization for the theory to be totally dissipative. Once this result has been obtained, a straight forward application of a general stability theorem due to Kreiss, Ortiz, and Reula, implies the results above mentioned.Comment: 10 pages, Late

Intelligent wireless web services: context-aware computing in construction-logistics supply chain

The construction industry has incurred a considerable amount of waste as a result of poor logistics supply chain network management. Therefore, managing logistics in the construction industry is critical. An effective logistic system ensures delivery of the right products and services to the right players at the right time while minimising costs and rewarding all sectors based on value added to the supply chain. This paper reports on an on-going research study on the concept of context-aware services delivery in the construction project supply chain logistics. As part of the emerging wireless technologies, an Intelligent Wireless Web (IWW) using context-aware computing capability represents the next generation ICT application to construction-logistics management. This intelligent system has the potential of serving and improving the construction logistics through access to context-specific data, information and services. Existing mobile communication deployments in the construction industry rely on static modes of information delivery and do not take into account the worker’s changing context and dynamic project conditions. The major problems in these applications are lack of context-specificity in the distribution of information, services and other project resources, and lack of cohesion with the existing desktop based ICT infrastructure. The research works focus on identifying the context dimension such as user context, environmental context and project context, selection of technologies to capture context-parameters such wireless sensors and RFID, selection of supporting technologies such as wireless communication, Semantic Web, Web Services, agents, etc. The process of integration of Context-Aware Computing and Web-Services to facilitate the creation of intelligent collaboration environment for managing construction logistics will take into account all the necessary critical parameters such as storage, transportation, distribution, assembly, etc. within off and on-site project