‘Physics of Living Systems’ Survey to Delineate New Subfield

The National Academies is currently undertaking the first-ever decadal survey of the “physics of living systems.” The study committee will review recent accomplishments of the field and identify emerging research directions, while also making the case for it being a true subdiscipline of physics, rather than a mere application of physics tools and techniques to biological phenomena.

At a virtual town hall last month, committee chair William Bialek, a physics professor at Princeton University, recounted how past surveys have treated research at the intersection of physics and biology.

“If you go back to the early decadal surveys of physics, the interaction between the physics community and the phenomena of life was very clearly categorized as an application of physics to things outside the field,” he said. Though the physics of living systems gained recognition in the early 2000s, he added, discussion of its work was nevertheless scattered across the physics decadal surveys prepared for the 2010s, such as the reports on Atomic, Molecular, and Optical Physics and Condensed Matter Physics .

“What’s new in this cycle is that we’re being asked to review the physics of living systems as a subfield of physics that stands on its own, along with elementary particle physics, condensed matter physics, astrophysics, nuclear physics, and so on,” he continued. “I think this is an incredibly exciting thing for our field. And we, as a community, have a great opportunity to sort of stake our claim to this part of physics and to the idea that what we do is firmly a part of physics.”

Calling the study a potential “field-defining moment,” he encouraged interested researchers to submit input to the committee. A collection of material it has received to date is available on the committee website.

Notably, the National Science Foundation, which is sponsoring the survey, already has a “Physics of Living Systems” program that funds research at scales ranging from single-cell dynamics to the collective behavior of animal populations. However, the study’s statement of task does not define its scope based on that program. It more generally instructs the committee to consider ways NSF and other funding agencies could “overcome traditional boundaries” to support research on the physics of living systems.

Committee members have made clear though that the survey is not intended to cover the field of biophysics as it has generally been defined.

Asked to comment on the difference between the fields, Bialek noted that the study’s title refers jointly to “biological physics/physics of living systems,” which he said suggested that “even the people who are asking for advice are a little unsure about how to describe this enterprise.”

He also contrasted the types of research that are presented at meetings of the Biophysical Society versus those of the American Physical Society Division on Biological Physics. “I think many of us find fantastically interesting things in both programs, but if you look statistically, you’ll see that those are very different cross sections through or rather different pieces of the field,” he said.

Speaking broadly about the evolution of the relationship between physics and biology, he said that around the turn of this century, “it became clear that if you came from the physics community and were interested in the phenomena of the living world, then you could still be a physicist, as judged by your physics colleagues. And so there is a distinction between biophysics as a branch of biology and the physics of biological systems or the physics of living systems as a branch of physics, and we are in a very deliberate sense charged with studying the latter.”

Another committee member, cell biologist Clare Waterman, offered a related explanation at a different meeting of the panel last month.

“I think a major issue that we’re dealing with is that the physics of living systems is not currently represented by any professional society, maybe a subgroup of the APS, but the Biophysical Society meeting is already well funded, well represented science,” she said.