We show that the evolution of the number density of rich clusters of galaxies breaks the degeneracy between (the mass density ratio of the universe) and 8 (the normalization of the power spectrum), 8 0:5 ' 0:5, that follows from the observed present-day abundance of rich clusters. The evolution of high-mass (Coma-like) clusters is strong in = 1, low-8 models (such as the standard biased CDM mod...

Little Higgs models offer a new way to address the hierarchy problem, and give rise to a weakly-coupled Higgs sector. These theories predict the existence of new states which are necessary to cancel the quadratic divergences of the Standard Model. The simplest version of these models, the Littlest Higgs, is based on an SU(5)/SO(5) non-linear sigma model and predicts that four new gauge bosons, ...

The most fundamental observable related to the weak interaction is the muon lifetime, τμ. With the electromagnetic two-loop contribution known1, τμ can be used unambiguously to extract the Fermi constant, GF = 1.16637(1)× 10 −5 GeV, where the uncertainty is completely dominated by experiment. Adding the fine structure constant, α, one can obtain two relations between the intermediate gauge boso...

Constraining tropospheric mixing timescales using airborne observations and numerical models P. Good, C. Giannakopoulos, F. M. O’Connor, S. R. Arnold, M. de Reus, and H. Schlager National Observatory of Athens, Greece Centre for Atmospheric Science, Cambridge, UK School of the Environment, University of Leeds, UK Max-Planck-Institute for Chemistry, Atmospheric Chemistry Department, Mainz, Germa...

We combine complementary datasets to constrain dark energy. Using standard Big Bang Nucleosynthesis and the observed abundances of primordial nuclides to put constraints on ΩQ at temperatures near T ∼ 1MeV , we find the strong constraint ΩQ(MeV) < 0.045 at 2σ c.l.. Under the assumption of flatness, using results from Cosmic Microwave Background (CMB) anisotropy measurements, high redshift super...

This paper presents a visual language called Miro for specifying and restricting operating system security configurations. A Miro picture specifies exactly what rights users have on files. A Miro constraint, also stated visually, restricts the set of Miro pictures which are considered legal. Such constraints on pictures give an exact specification of security policies and a practical method for...

We argue that the current, predominantly task-oriented, approaz~hes to modularizing text • generation, while plausible and useful conceptually, set up spurious conceptual and operational constraints. We propose a data-driven approach to modularization and illustrate how it eliminates • •the previously ubiquitous constraints on combination of evidence across modules and on • control. We also bri...

In a constrained pseudorandom function (PRF), the master secret key can be used to derive constrained keys, where each constrained key k is constrained with respect to some Boolean circuit C. A constrained key k can be used to evaluate the PRF on all inputs x for which C(x) = 1. In almost all existing constrained PRF constructions, the constrained key k reveals its constraint C. In this paper w...