Gravitational lensing in the age of the ILT and SKA-VLBI

The first VLBI observations of strong gravitational lensing were reported about 44 years ago, and since then, the field has grown to become an important tool for studying galaxy formation, dark matter and the distant Universe at the highest angular resolutions possible in astronomy. Unfortunately, only a handful of radio-bright lenses are known, identified mainly from the first systematic lens surveys and some serendipitous discoveries over the last four decades. However, this is set to change with the large area all-sky surveys being carried out now with the Low Frequency Array (LOFAR) and with the Square Kilometre Array (SKA) in the future, which will discover tens of thousands of new systems. Here, we present the first results from observations of known gravitational lenses with LOFAR and the new discoveries being made with the International LOFAR Telescope (ILT). For the latter, we will present a novel machine-learning based method for identifying lenses with the ILT, from which, we have determined the types of lenses that the ILT is likely to find. We will show the first results from applying this and standard catalogue-based searches for lenses in the first batch of data from the ILT, and will present the first set of new lens candidates to be identified with LOFAR. Finally, we will discuss the prospects for lens discovery with the SKA and the importance of having a VLBI array within Africa for realising the unique science cases that are only possible with strong gravitational lensing.