I'm a biologist by profession, but I have a basic question about the effect of heat on light wave/particle, that could be monitor('able). If there's a slight change in the temperature of the medium, through which light is passing, due to a thermodynamic heat changes occuring in the medium of the order of 0.1 microcals, would that have any detectable effect on any of the properties of the light? If so what would be the relationship with respect to change in temperature? I'd be grateful if anyone could respond to this question! Thanks in advance. Dreams.