Mairhofer - Ways of observing. Detectors and the epistemic community

Lukas Mairhofer
Am Sande 5
21335 Lüneburg 
lukas.mairhofer@univie.ac.at

Lukas Mairhofer is a experimental physicist and philosopher of science, holding PhDs in both disciplines. His research focuses on philosophical issues of modern physics and the cultural impact of quantum mechanics. He studied at the University of Vienna complemented by semesters abroad at Jawarhalal Nehru University, the University of Helsinki, UC Berkeley and the University of Konstanz as well as a secondment at the AEGIS collaboration at CERN. His research was supported by fellowships at the Internationale Forschungszentrum Kulturwissenschaften (Vienna) and the graduate schools "Das Reale in der Kultur der Moderne (Konstanz) as well as "Complex Quantum Systems" (Vienna). His thesis on "Bertolt Brecht's interference with Quantum Physics" won the doc.award 2015. He published in both fields, such as:

- Quantum-assisted metrology of neutral vitamins in the gas-phase, in: Angewandte Chemie International Edition 56 (2017)

- Traces and Patterns. Pictures of Interferences and Collisions in the Physics Lab, together with Anne Dippel, in: Bettina Bock von Wülfingen (Ed.), Traces. Generating What Was There. de Gruyter (2017)\\

Research Project

I will investigate this dual function of computer simulations for detectors in contemparary physics experiments.Detectors enhance our senses, thus redefining the epistemic community. Mediating between the observers and the observed, they can be accounted for as part of the investigated object as well as part of the investigating subject.

Detectors are linked to computer simulations on at least two different levels. On the one hand, computer simulation is part of almost all experiments in current fundamental research: In setting them up, often crucial parts of experiments are first simulated using finite elements methods. Later the simulated behavior of the detector becomes part of the data evaluation. This way, computer simulations have an important epistemological function, adding a distinct element to the process of scientific cognition. The model is implemented by the experimental practice, in which we apply it to reality. But at the same time we need to reverse this step and translate the apparatus performing the implementation into a theoretical model.

On the other hand, simulation is part of the detection process itself: The results of experiments are usually obtained by fitting models to the data, with or without free parameters. In modern particle physics simulations enter the measurement process on an even more fundamental level. The detection of new particles requires to identify a signal against a background that is orders of magnitude larger then the signal itself. These measurements become only possible because the background is not primarily given as white noise but consists of events that are already understood. Monte Carlo simulations of those events make sense out of the noise and allows to subtract it.