Building Bridges to Scientific Discovery

Cross-disciplinary research is expected to be a hot topic at #LINO24. Benjamin Skuse explores some of the benefits and challenges of breaking through traditional disciplinary boundaries.

Thinking back to my time as an applied mathematician, I cringe at how I looked upon all other scientific disciplines – the ‘soft sciences’ as I and some of my then colleagues disparagingly referred to them – as inferior and ultimately derivate of pure mathematics and physics. Fortunately, this attitude is dying out, as it becomes ever more blindingly obvious that the burning problems in science and society call for new approaches and multidisciplinary cooperation.

Other Worlds Beyond the Solar System

For instance, take the perennial question: are we alone in the universe? For literally centuries, it had been a subject reserved for philosophical debate until two planets orbiting a pulsar were discovered in 1992 by astronomers Alex Wolszczan and Dale Frail, and then an exoplanet orbiting a Sun-like star was announced by Michel Mayor and Didier Queloz in 1995; the latter pair going on to jointly receive half of the 2019 Nobel Prize in Physics for their achievement.

Despite these worlds having no chance of harbouring life, discovering the first exoplanets showcased humanity’s new ability to probe other worlds beyond the Solar System. In the decades since, over 5,500 exoplanets have been documented. Yet astronomers are only really equipped to spot and figure out the basic properties of these worlds. To get a handle on whether exoplanets are habitable and might be supporting life, they need to work with a host of experts from other disciplines. This is why planet-hunting astronomers now collaborate regularly with Earth scientists and heliophysicists, as well as researchers from new interdisciplinary fields like astrobiology and exoplanet science.

So far, the search for habitable alien worlds has come up empty, in large part due to the sheer technological challenge of spotting and characterising promising Earth-like worlds circling around Sun-like stars. But with huge next-generation telescopes like the very literally named Extremely Large Telescope pushing the limits of exoplanetary discovery from the ground in this decade, and the planned space-based Habitable Worlds Observatory expected to interrogate at least 100 promising star systems to hopefully find around 25 potentially habitable exoplanets in the 2040s, humanity has never been closer to finding out if we are alone in the universe – all thanks to cross-disciplinary research.

Complexity Science

Collaborative studies spanning disciplines are also essential in the intrinsically complex field of climate science. The 2021 Nobel Prize in Physics was awarded for innovators in the field of complexity science (whose work actually appeared before the term ‘complexity science’ had even been coined), one half jointly to climate scientists Syukuro Manabe and Klaus Hasselmann, and the other to statistical physicist Giorgio Parisi. 

Manabe and Hasselmann’s contributions were made in the 1960s and 70s. But some of the outstanding cross-disciplinary contributions to climate science came later, between 1970 and 2000 when seminal works from groups consisting of mathematicians, physicists, meteorologists and others were forming the foundations for chaos theory. Fast forward to today and a similar multidisciplinary approach is needed, but not just to satisfy scientific curiosity. Instead, to address the existential crisis that is climate change.

This is happening at all scales, from individual research groups to vast international cross-disciplinary collaborations. Most prominently, cross-disciplinary collaboration underpins all work at the Intergovernmental Panel on Climate Change (IPCC) – the de facto home of climate science assessment shaping national and global policies. In 2014, the IPCC released the Fifth Assessment Report (AR5). AR5 was written by 831 global experts who were drawn from fields including meteorology, physics, oceanography, statistics, engineering, ecology, social sciences and economics. And the report’s findings were based on meta-analysis of 9,200 peer-reviewed studies. These findings – which included that warming of the climate system is unequivocal and (extremely likely) caused by human influence – heavily influenced the landmark Paris Agreement in 2015 leading to real-world global impact on policy.

Though cross-disciplinary collaboration is clearly having a huge influence on humanity’s ability to address the most intractable scientific questions and impact our most pressing societal problems, there remain barriers to conducting high-quality work alongside scientists from other disciplines.

In 2023, 18 editors from Journal of Physics: Complexity offered their personal thoughts on the challenges of multidisciplinary research. The most cited impediment to effective collaboration was communication. Despite there being many simple strategies to overcome communication issues, the editors felt that taking the time to really listen and learn from each other remains a critical hurdle to effective multidisciplinarity. What’s more, communicating multidisciplinary work to the wider community remains a challenge, with only a few conferences and journals dedicated to interdisciplinary research.

Establishing Multidisciplinary Research

Other barriers are structural, where there is little encouragement, recognition or reward for leaders in their disciplines to come out of their deep burrows of expertise and address bigger questions. Research institutes such as RIKEN in Japan and the Santa Fe Institute in the US are prominent exceptions, overtly defying this convention by breaking down obstacles created by academic disciplines and institutional structures so that the best and brightest collectively work on the most impactful problems.

But elsewhere, these obstacles largely remain. Most research funding is still focused on disciplinary themes, most universities organize their departments by disciplines, and teaching largely remains heavily discipline-focused. These factors combine to make it challenging to both nurture the next generation of researchers and keep hold of the current generation, with cross-disciplinary researchers often finding it difficult to move between institutions, or secure tenure or promotions.

However, a template is beginning to emerge, with many universities like the University of Sydney establishing multidisciplinary research centres focused on different important topics, and universities such as University College London stimulating cross-disciplinary research projects at the institutional level around complex global ‘grand challenges’, and offering broad multidisciplinary undergraduate and postgraduate courses combining elements from several disciplines. These and many other efforts are ensuring scientists are prepared to face today’s rapidly changing world with flexibility and an openness to new approaches that will give humanity the best chance of addressing global challenges.