“My main interest lies in studying theoretical models that are generally known as physics beyond the Standard Model – we call them ‘Beyond the Standard Model’ or BSM for short.”

But why do we need such theories at all? The Standard Model is extremely successful when it comes to describing the basic building blocks of nature known to us. Therefore, we would like to consider it as the fundamental theory of nature. And yet, there are reasons to assume that it is an effective theory: it is valid at those energy and length scales that are currently experimentally accessible. But at higher energies or shorter distances, we need to expand this theory to arrive at a more fundamental description of nature.

This is where BSM models come into play: they are intended to explain what the Standard Model cannot explain, but at the same time leave its correct predictions unchanged. That’s what fascinates me most about my work – there are many open problems in Particle Physics that we can connect with our research. It’s as if we’re bringing together loose ends of modern physics.

Specifically, I mainly deal with models that take into account additional (spatial) dimensions. If these dimensions are ‘curved’, they allow us, for example, to understand why the fermion masses are as they are in the Standard Model. For my work, I use both an ordinary PC and the Mainz supercomputer MOGON II. But at the beginning there is always an idea. This becomes a model on paper, which I later test on the computer. I am sure that our research area directly promotes the exchange of these ideas and thought experiments – another big plus of my work.”

Javier Castellano has been a doctoral candidate in Prof. Dr. Matthias Neubert’s work group since October 2017. After completing his master’s degree in Valencia, Spain, his supervisor drew his attention to the Mainz work group in Theoretical High Energy Physics. He finally came to Mainz via the “Symmetry Breaking” graduate school associated with PRISMA⁺, which has now expired.