Signals, Noise and Decoherence


Weinstein, S. (2015). Signals, Noise and Decoherence. Perimeter Institute. https://pirsa.org/15040063


Weinstein, Steve. Signals, Noise and Decoherence. Perimeter Institute, Apr. 28, 2015, https://pirsa.org/15040063


          @misc{ pirsa_15040063,
            doi = {10.48660/15040063},
            url = {https://pirsa.org/15040063},
            author = {Weinstein, Steve},
            keywords = {Quantum Foundations},
            language = {en},
            title = {Signals, Noise and Decoherence},
            publisher = {Perimeter Institute},
            year = {2015},
            month = {apr},
            note = {PIRSA:15040063 see, \url{https://pirsa.org}}

Steve Weinstein University of Waterloo


 It is well known - to those who know it - that noise and randomness can enhance signal resolution. I'll present an easy-to-follow example from digital audio that illustrates the way in which adding noise ("dither") prior to measurement enhances the accuracy with which we are able to distinguish the features of the sound or image. I will then explore the way in which the environmental interactions prior to measurement ordinarily characterized as environment-induced decoherence may play a similar role.  The paradoxical conclusion is that the quasiclassical behavior associated with such systems may be a more accurate representation of the quantum world than what we think of as fully "quantum" behavior, which may in turn be artifactual, the result of errors similar to those introduced by the discretization (also known as "quantization") of data in digital audio and imaging.