RGIsearch: A C++ program for the determination of Renormalization Group Invariants

RGIsearch is a C++ program that searches for invariants of a user-defined set of renormalization group equations. Based on the general shape of the $\beta$-functions of quantum field theories, RGIsearch searches for several types of invariants that require different methods. Additionally, it supports the computation of invariants up to two-loop level. A manual for the program is given, including the settings and set-up of the program, as well as a test case

The economic explanation of the jump of the co-state variable

Price Theory;microeconomics

Monetary Policy, Commodity Prices and Infl ation – Empirical Evidence from the US

The past years were characterized by unprecedented rises in prices of commodities such as oil or wheat and inflation rates moved up above the mark of two percent per annum. This led to a revival of the debate whether commodity prices indicate future CPI inflation and if they can be used as indicator variables for central banks or not. We apply various econometric methods like Granger causality tests and SVAR models to US data. The results corroborate the notion that there was a strong link between commodity prices and CPI inflation in the 1970s and the beginning of the 1980s. For a more recent sample, the relationship has weakened, respectively diminished.Monetary policy; commodity prices; infl ation; United States; SVAR

Final-state QED Multipole Radiation in Antenna Parton Showers

We present a formalism for a fully coherent QED parton shower. The complete multipole structure of photonic radiation is incorporated in a single branching kernel. The regular on-shell 2 to 3 kinematic picture is kept intact by dividing the radiative phase space into sectors, allowing for a definition of the ordering variable that is similar to QCD antenna showers. A modified version of the Sudakov veto algorithm is discussed that increases performance at the cost of the introduction of weighted events. Due to the absence of a soft singularity, the formalism for photon splitting is very similar to the QCD analogon of gluon splitting. However, since no color structure is available to guide the selection of a spectator, a weighted selection procedure from all available spectators is introduced.Comment: 33 pages, 12 figures. Added subsection 4.3 and some comments and references per reviewer request. Version accepted by JHE

Competing Sudakov Veto Algorithms

We present a way to analyze the distribution produced by a Monte Carlo algorithm. We perform these analyses on several versions of the Sudakov veto algorithm, adding a cutoff, a second variable and competition between emission channels. The analysis allows us to prove that multiple, seemingly different competition algorithms, including those that are currently implemented in most parton showers, lead to the same result. Finally, we test their performance and show that there are significantly faster alternatives to the commonly used algorithms.Comment: 16 pages, 1 figur

The importance of forest type when incorporating forest edge deposition in the evaluation of critical load exceedance

This paper provides an assessment of the effect of incorporating edge deposition in the evaluation of critical load exceedance in forests, taking into account pollutant type, meteorological conditions, edge orientation, and forest type. In particular we have calculated critical load exceedance in five Flemish regions differing in forest fragmentation extent and/or share of coniferous forest