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CREOL, Room A214


The key purpose of this colloquium is to bridge the gap between our highly repeated word “photon” and our consistent use of the Huygens-Fresnel diffraction integral as the key analytical tool to analyze most optical propagations. This includes all forms of image processing and the evolution of spatial modes in passive fibers and active laser cavities. The hybrid photon model establishes that, at the moment of atomic emission, ΔE = hν is a discrete packet of energy. However, this energy packet then immediately triggers the evolution of a semi-exponential wave packet that keeps propagating out diffractively, as all waves do, leveraging the tension field that sustains their perpetual propagation. The model is supported by the experimental knowledge that spontaneous emissions show Lorentzian spectral line-width modeled by the causal formulation of spectrometry [“Causal Physics: Photon by Non-Interaction of Waves”, by C.R., Taylor & Francis, 2014].

Biography: Dr. Chandra Roychoudhuri is a Research Professor at the Physics Department, the University of Connecticut. He was a Fulbright Scholar; did his PhD, Institute of Optics, University of Rochester. Worked for TRW, Perkin Elmer and United Technologies for 14 years. CR has carried out wide ranges of applied & basic experiments in optical sciences. He is a Fellow of OSA and SPIE; he had also served both the societies as a Board Member. He has published, “Causal Physics: Photon by NonInteraction of Waves” (NIW) [CRC, 2014]. He is a life-long promoter of perpetual enquiry of the nature of light. He rediscovered the NIW-property, which Huygens underscored in his original book, and generalized its deep implications in classical optical phenomena, interpretation of Quantum Mechanics, space as a physical field, cosmological redshift, etc.


ChandraSekhar Roychoudhuri, Ph.D.

Physics Department
University of Connecticut
Storrs, Connecticut


Debashis Chanda NanoScience Technology Center