Abstract. We discuss the multiplicity of the non-trivial zeros of the Riemann zetafunction and the summatory function M(x) of the Möbius function. The purpose of this paper is to consider two open problems under some conjectures. One is that whether all zeros of the Riemann zeta-function are simple or not. The other problem is that whether M(x) ≪ x holds or not. First, we consider the former pr...

I propose an approximation scheme for asymptotically free field theories combining both weak coupling and strong coupling series. The weak coupling expansion is used to integrate the high frequency modes and the resulting low energy effective theory is solved using the strong coupling expansion. In some models there exists an intermediate scale at which both expansions make sense. The method is...

In the paper the asymptotic distributions of sample optimal portfolio weights are derived. This is done under the weak assumption on the data generating process. It is assumed that the k -dimensional vector of asset returns follows a VARMA( 1 1 , p q )GARCH( 2 2 , p q ) process with the elliptically distributed error process. The estimators of the mean vector and the covariance matrix of the as...