Recently it has been argued that, because tachyonic matter satisfies the Strong Energy Condition [SEC], there is little hope of avoiding the singularities which plague S-Brane spacetimes. Meanwhile, however, Townsend and Wohlfarth have suggested an ingenious way of circumventing the SEC in such situations, and other suggestions for actually violating it in the S-Brane context have recently been...

In a recent paper, Lee and Moharrami [13] construct a family of metrics (Xn, dn) with |Xn| = N , such that (Xn, √ dn) embeds into L2 with constant distortion, but embedding (Xn, dn) into a metric of negative type requires distortion Ω̃(log 1N). In this paper, we build on their analysis, and improve their result by showing an Ω̃(log 1N) lower bound for embedding (Xn, dn) into a metric of negative ...

We present in this paper a procedure to automatically discover a user s personal topics by clustering their emails. Unlike previous work, we automatically label topics using appropriate keywords. We show that, in order to get appropriate keywords, we must apply strong filters that use domain knowledge about e-mail and the workplace of the user. We demonstrate these keywords by creating an email...

In this paper the long time asymptotic behavior of solutions of semilinear symmetric hyperbolic system including Maxwell s equations and the scalar wave equation in an ar bitraty domain are investigated The possibly nonlinear damping term may vanish on a certain subset of the domain It is shown that the solution decays weakly to zero if and only if the initial state is orthogonal to all station...

We consider a labelled tableau presentation of constant domain rst-order S5 and prove a strong cut-elimination theorem.