Radiative Transfer

Radiative transfer (RT) is the study of propagation of light inside participating media. Since late 19th century RT has been studied intensely to understand the light distribution in the atmosphere and emerging from stellar surfaces. The classic in this field is the book Radiative Transfer by Subrahmanyan Chandrasekhar. This book develops the theory of RT in plane parallel media in a mathematically elegant way, characteristic of all of Chandra's work.

My work focuses on studying the light propagation inside and emerging from large water bodies like lakes and oceans. Such water bodies can be treated as being uniform and in the horizontal direction and this reduces the problem to one of plane parallel geometry. Thus, much of Chandrasekhar's work can be reused for this ocean optics problem.

Recently interest has been revived in classic RT theory for two main applications. The first is study of fluids in which light propagation is of such intensity that it contributes significantly or even dominates the flow. This is the regime of radiation hydrodynamics and is of utmost importance in target fusion systems. Radiation hydrodynamics is an extremely complex subject, mainly due to the different scales involved (speed of light to speed of sound) in the physics.

The second application is to realistic computer graphics. Most work in this field has been hitherto focused on surface-to-surface transfer in which the intervening medium does not affect the light distribution. These applications can be done using traditional ray tracing or classical radiosity based methods from thermodynamics. Recently, however, the effect of the intervening medium has also been investigated, mainly for simulating realistic skin models and taking into account media like fog or murky water. This latter problem is particularly complicated as the number of independent variables in the governing equations is large and geometry can be rather complicated. I am interested in the latter problems and have written a discrete-ordinates Discontinuous Galerkin code to solve the RT equation in arbitrary geometries.


	Radiative Transfer Radiative Transfer Radiative transfer (RT) is the study of propagation of light inside participating media. Since late 19th century RT has been studied intensely to understand the light distribution in the atmosphere and emerging from stellar surfaces. The classic in this field is the book Radiative Transfer by Subrahmanyan Chandrasekhar. This book develops the theory of RT in plane parallel media in a mathematically elegant way, characteristic of all of Chandra's work. My work focuses on studying the light propagation inside and emerging from large water bodies like lakes and oceans. Such water bodies can be treated as being uniform and in the horizontal direction and this reduces the problem to one of plane parallel geometry. Thus, much of Chandrasekhar's work can be reused for this ocean optics problem. Recently interest has been revived in classic RT theory for two main applications. The first is study of fluids in which light propagation is of such intensity that it contributes significantly or even dominates the flow. This is the regime of radiation hydrodynamics and is of utmost importance in target fusion systems. Radiation hydrodynamics is an extremely complex subject, mainly due to the different scales involved (speed of light to speed of sound) in the physics. The second application is to realistic computer graphics. Most work in this field has been hitherto focused on surface-to-surface transfer in which the intervening medium does not affect the light distribution. These applications can be done using traditional ray tracing or classical radiosity based methods from thermodynamics. Recently, however, the effect of the intervening medium has also been investigated, mainly for simulating realistic skin models and taking into account media like fog or murky water. This latter problem is particularly complicated as the number of independent variables in the governing equations is large and geometry can be rather complicated. I am interested in the latter problems and have written a discrete-ordinates Discontinuous Galerkin code to solve the RT equation in arbitrary geometries.