Last week, we hosted a major international particle physics conference on campus at The University of Birmingham. Over 300 participants from 41 countries discussed a wide range of scientific questions connected to the CERN Large Hadron Collider where five years ago the University played a central role in the Nobel-prize recognised Higgs boson discovery.

Our ability to attract so many international colleagues to a meeting such as this relies on the reputation of the UK as a good scientific partner, that is offering relatively straightforward access to foreign visitors, having a vibrant and internationalised scientific community and above all providing leadership and excellence. This perception of quality is well placed; analysis by Thomson Reuters of average numbers of citations per research paper shows the UK to be ranked first in the world across each of astronomy, particle and nuclear physics over the last five years. However, there are real dangers that this could all change after Brexit.

Like many other areas of academia, funding for fundamental science in the UK has been getting increasingly tight throughout the current period of austerity. This is making it increasingly difficult to maintain UK leadership in the largest international projects such as the LHC and the LIGO detectors where gravitational waves were recently discovered; projects which require steady, reliable funding over long time periods to succeed. There are at least three reasons why those of us working in basic science fear that Brexit will seriously exacerbate the already serious situation.

Firstly, in deciding funding priorities in these uncertain times, the instinct of government is to place increased emphasis on immediate economic impact, directly linking funding to near-term commercial potential. In fact, there has been significant uplift in overall funding for science under the current government through the Industrial Strategy Challenge Fund, which is designed to support collaborations between industry and the UK science base, aiming to address the UK's historic weakness in gaining financial benefit from its unquestioned excellence in basic science. However, tapping into these resources is not so easy if your focus is fundamental scientific questions such as Higgs bosons, gravitational waves or habitable planets orbiting stars that are light-years away.

Secondly, in the face of the long-term slow-but-steady decline in UK funding for basic Science, successful research groups have generated an increasing fraction of their funding from sources beyond UK government. For basic science, the outstanding opportunity of this type has been through the Horizon 2020 EU framework for research and innovation and its predecessors. These frameworks offer funding schemes that encourage mobility of young researchers between EU countries, build international training networks and most importantly provide highly competitive European Research Council (ERC) grants to individuals evaluated solely on the basis of 'scientific excellence'. Detailed statistics from the period between 2007–13 reveal that 22.1 per cent of all ERC grant awardees were working in UK institutes, the largest of any nation by almost a factor of two. Similarly tapping into the increased €13 billion ERC budget for the 2014–20 period has been increasingly important to UK science. Apart from compensating for the decline in UK funding, the bottom-up, non-risk-averse approach has provided a desperately needed mechanism to sustain diversity in the UK's basic science programme. It is therefore vital that we either find a way to remain eligible for ERC grants, or consider devising an alternative UK funding mechanism that also makes awards based only on scientific excellence to replace them.

Lastly, the expected post-Brexit restrictions of free movement of people poses enormous dangers across the whole of academia. Much of our current success has been based on being able to attract and freely recruit the best scientists from across the EU, leading to a diversity of experience and knowledge among our researchers, cross-fertilising ideas and tapping into extended networks of connections and collaborations. My own group is perhaps a typical example. Of 32 postdoctoral personnel, 14 are of UK nationality, 14 are non-UK EU citizens and four are from outside the EU. It is essential to the continued success of British fundamental science that not only these colleagues are allowed to remain on uncompromised terms, but that we continue to be able to add excellent international colleagues to our ranks.

As I have written previously, the long-term economic, as well as cultural benefits of fundamental science are well established and extend well beyond the most often-cited example of the invention of the worldwide web. In these uncertain times, it's vital not to focus too strongly on the immediacy at the expense of the long-term vision and technology drivers offered by basic science.

As Brexit progresses, we face serious risk of doing irreparable damage to our basic science base. It is ironic that our recent conference took place against the backdrop of the triggering of Article 50. I sincerely hope we will remain able to organise more meetings like it in the future.

Professor Paul Newman
Professor of Particle Physics, School of Physics and Astronomy, University of Birmingham