Vibration theory of olfaction have a vibrational energy mode compatible with the difference in energies between two energy levels on the receptor, so electrons can travel through the molecule via inelastic electron tunneling, triggering the signal transduction pathway. The vibration theory is discussed in a popular but controversial book by Chandler Burr. The odor character is encoded in the ratio of activities of receptors tuned to different vibration frequencies, in the same way that color is encoded in the ratio of activities of cone cell receptors tuned to different frequencies of light. An important difference, though, is that the odorant has to be able
Cycles of Time should plunge into. The American fiction writer Anthony Doerr in "The Boston Globe" writes "Penrose has never shied away from including mathematics in his texts, and kudos to his publisher for honoring that wish. That said, the second half of "Cycles of Time" offers some seriously hard sledding"; "If you'll forgive a skiing metaphor, "Cycles of Time" is a black diamond of a book." Cycles of Time Cycles of Time: An Extraordinary New View of the Universe is a science book by mathematical physicist Roger Penrose published by The Bodley Head in 2010. The book outlines Penrose's Conformal Cyclic Cosmology