Safe and secure future AI-driven railway technologies: challenges for formal methods in railway

In 2020, the EU launched its sustainable and smart mobility strategy, outlining how it plans to have a 90% reduction in transport emission by 2050. Central to achieving this goal will be the improvement of rail technology, with many new data-driven visionary systems being proposed. AI will be the enabling technology for many of those systems. However, safety and security guarantees will be key for wide-spread acceptance and uptake by Industry and Society. Therefore, suitable verification and validation techniques are needed. In this article, we argue how formal methods research can contribute to the development of modern Railway systems -- which may or may not make use of AI techniques -- and present several research problems and techniques worth to be further considered.