Accurate simulation of the finite density lattice Thirring model

We present a study of the finite density lattice Thirring model in 1+1 dimensions using the world-line/fermion-bag algorithm. The model has features similar to QCD and provides a test case for exploring the accuracy of various methods of solving sign problems. In the massless limit and with open boundary conditions we show that the sign problem is an artifact of the auxiliary field approach and is completely eliminated in the fermion bag approach. With periodic boundary conditions the sign problem is mild in the fermion bag method. We present accurate results for various quantities in the model that can be used as a benchmark for comparison with other methods of solving sign problems.Comment: 8 pages, 7 figures. Proceedings of the 35th International Symposium on Lattice Field Theor

Ideal Walking Dynamics via a Gauged NJL Model

According to the Ideal Walking Technicolor paradigm large mass anomalous dimensions arise in gauged Nambu--Jona-Lasinio (NJL) models when the four-fermion coupling is sufficiently strong to induce spontaneous symmetry breaking in an otherwise conformal gauge theory. We therefore study the $SU(2)$ gauged NJL model with two adjoint fermions using lattice simulations. The model is in an infrared conformal phase at small NJL coupling while it displays a chirally broken phase at large NJL couplings. In the infrared conformal phase we find that the mass anomalous dimension varies with the NJL coupling reaching $\gamma_m \sim 1$ close to the chiral symmetry breaking transition, de facto making the present model the first explicit realization of the Ideal Walking scenario.Comment: 10 pages, 4 tables and 7 figure

Running coupling in SU(2) with adjoint fermions

We present a measurement of the Schr\"odinger Functional running coupling in SU(2) lattice gauge theory with adjoint fermions. We use HEX smearing and clover improvement to reduce the discretization effects. We obtain a robust continuum limit for the step scaling, which confirms the existence of a non-trivial fixed point.Comment: Contribution to SCGT12 "KMI-GCOE Workshop on Strong Coupling Gauge Theories in the LHC Perspective", 4-7 Dec. 2012, Nagoya University, 4 pages, 2 figure

Embedded mobile application for controlling acoustic panels

Abstract. This thesis work is about acoustic panels and planning a software that would control these kinds of panels. The software is supposed to take information from the panels and then use that information for moving the acoustic panels to a desired location. The application is for mobile environment for both smart phones and tablets. This means that there are some constraints for the software such as scaling the panels so that all the panels can be used when moving the panels. This work introduces heuristic and design science theory and builds the application plan as an artifact from there onwards. The plan is based upon the original requirements for this application. This plan for the application meets the requirements set upon it by the customer. The plan was created so that the basic functionalities that were discussed with the customer were satisfied. This included connection to panels, drawing a scaling panel view, moving panels, centring panels and so forth. The application was evaluated with two sets of heuristics. First one was the heuristics created by Nielsen 1995 and second heuristic was self-built. Nielsen’s heuristics were meant for a more general usage while the set of heuristics that were self-build were meant for more general usage. The heuristic evaluation provided results which were that the application needs at least more error prevention, documentation and a better way or representing panels actual physical location on the wall. Error prevention was a major issue in a case that one or more of the panels were broken and needed to be fixed. Documentation was more of an issue from the user’s perspective in case some of the actions or error messages were such that the user did not understand them. Last issue of presenting the panel positions better in relation to the physical wall was an issue basically because the user needs to know where the panels are without too much difficulty. If the user is confused about panel location, they cannot be sure which panels to move. These issues were discussed in the second iteration of the plan for this application. The second iteration was done in writing and a picture of the new user interface after the heuristic evaluation was done. This iteration discussed and solved these problems. For the limitations of this work there were issues with author doing the heuristic evaluation while not being an expert, implementation not being done in the scope of this work and implementation details not being discussed. For future research, the implementation should be done and the heuristics that were self-built need more though put into the