Nonlinear Biomedical Physics

Department of Physics

Dr Dmitry G. Luchinsky

Dr Dmitry Luchinsky

I was born in Moscow in 1959, two years before the first human flew in outer space, and ten years before the culmination of the space race when the first human stepped on the Moon. Not surprisingly, I was interested in physics from my childhood. After graduation with honours from the Physics Department of Moscow State University in 1983 I worked on what was one of the hottest topics in experimental physics at that time: the picosecond laser spectroscopy of semiconductors. My PhD thesis (1986-1991) was devoted to experimental investigations of optically bistable devices, which were perceived as the elements of optical computers. The size and operating powers of these devices had to be made as small as possible, so that the effect of intrinsic fluctuations was an important factor limiting their range of stable operation. Accordingly I had to spend a lot of time trying to eliminate the effect of fluctuations and to improve signal-to-noise ratio (SNR). Prof. Mark Dykman who was then visiting our research group in Moscow explained to us that fluctuations can actually be very helpful and, quite counterintuitively, that it is possible to improve the SNR by adding noise to a device. I found this subject fascinating and spent many years researching the role and nature of fluctuations.

This work brought me to Prof. Peter McClintock’s group in Lancaster on several occasions as a Royal Society Visiting Research Fellow. It became clear that we shared a passion for understanding the nature of fluctuations. I moved to Lancaster in 1995 to continue this research in collaboration with Peter, Mark Dykman, and a number of outstanding researchers from all over the world, including Prof. Riccardo Mannella (Pisa), Prof. Nigel Stocks (Warwick), Dr Vadim Smelyanskiy (NASA), Dr Igor Khovanov (Warwick), and Dr Alexander Silchenko (Germany). Within the framework of this international collaboration we have investigated a number of fascinating counterintuitive effects in the physics of fluctuations including stochastic resonance, Brownian ratchets, and noise-enhanced dynamical Bayesian inference. This research prompted us to look deeper into fundamental issues of fluctuational dynamics and, in particular, to investigate the deterministic Hamiltonian structure underlying large fluctuations and to explore the nature of time-reversal symmetry-breaking in non-equilibrium fluctuations.

We have also probed deeper into areas, where fluctuations are inherently important and play a nontrivial positive organizing role. That is how I became interested in the stochastic dynamics of living systems and ion channels and started to work with Dr Aneta Stefanovska (Lancaster). In this ongoing research I have been particularly intrigued and impressed by the extraordinary complexity of what is one of the simplest bio-electronic devices developed by Nature: ion channels in biological membranes. They are not only able to conduct ions at a steady rate of 10^8 ions per second through the nano-pore, but are also able to separate ions of the same polarity and practically identical radius in the ratio 1/1000. We hold an EPSRC grant to investigate this extraordinary phenomenon within the framework of the theory of stochastic nonlinear dynamics.

More recently I had an opportunity to combine my childhood passion for space travel with my mature scientific interests in fluctuations, by joining the research programme of Dr Vladimir Smelyanskiy (NASA) on the health management of the solid rocket motors being developed for heavy lifting, as well as for exploration by future crews. This outstanding research, which is conducted exclusively by NASA and not by any other commercial or government organization, can help to make the next flight to the Moon a safer one and will surely bring a number of other fascinating discoveries on the way. Remarkably, it depends on closely similar ideas and principles to those we have been developing for the description of living systems on Earth ...more