Physical Biology : challenges for our second decade.

It is quite an honor to be asked to become the third editor-in-chief of Physical Biology . I am following in the footsteps of Tim Newman, who served with energy and enthusiasm. Hopefully, the entire community fully appreciates his contributions to moving the field forward. Thank you, Tim! With the honor, however, goes a clear responsibility. Our journal has survived its birth pangs and emerged as a serious venue for publishing quality research papers using physical science to address the workings of living matter. With the support of scientists in this field and with the ongoing commitment of the IOP, we have successfully reached adolescence. Yet, there is clearly much room to grow and there are clear challenges in defining and maintaining our special niche in the publishing landscape. In this still-developing state, the journal very much mimics the state of the field of physical biology itself. Few scientists continue to question the relevance of physical science for the investigation of the living world. But, will our new perspective and the methods that come with it really lead to radically new principles of how life works? Or, will breakthroughs continue to come from experimental biology (perhaps aided by the traditional physicist-as-tool-builder paradigm), leaving us to put quantitative touches on established fundamentals? In thinking about these questions for the field and for the journal, I have tried to understand what is really unique about our joint endeavors. I have become convinced that living matter represents a new challenge to our physical-science based conceptual framework. Not only is it far from equilibrium, as has been generally recognized, but it violates our simple notions of the separability of constituents, their interactions and the resulting large-scale behavior. Unlike, say, atomic physicists who can do productive research while safely ignoring the latest developments in QCD (let alone particle physics at higher energies), we do not yet understand when the details of proteins and nucleic acids structure and function can be assumed constant when considering the cell. This problem is even more serious as we try to set higher sights and think of cells as constituents of tissue, organ and organism. Trying to understand higher-order biological systems is a bit like trying to play a board game where the pieces and rules are constantly changing, somehow in concert with what is happening at the scale of the game. Others will undoubtedly have their own view of what is really difficult and different about living systems. One of the roles of Physical Biology should therefore be to provide a needed forum to address some of these really difficult questions. Of course, most papers will operate with the safety-setting on, and will use established ideas in physics, either experimental or theoretical, to further our quantitative appreciation of living systems. These papers are without doubt an absolutely necessary part of the field, and we hope that our journal can serve as a home for the best of these. But, my real hope is that we can attract papers that really try to break new ground, that suggest ways in which the living world is not just an extremely messy example of the same phenomena that can be studied in non-biological contexts. Amazingly, this hope is actually shared by many leading biologists. In one of the most influential papers on cancer research in the past decades. Hanahan and Weinberg argue that 'one day, we imagine that cancer biology and treatment-at present, a patchwork quilt of cell biology, genetics, histopathology, biochemistry, immunology, and pharmacology-will become a science with a conceptual structure and logical coherence that rivals that of chemistry or physics.' We should take up the challenge, not just for cancer, and Physical Biology should help. Figuring out exactly how best to do this is now my responsibility, and I look forward to hearing from you and working with all of you, in order to make it happen.