Traditionally the quantum time problem is the question Is time a parameter or an observable in quantum mechanics? The essence of a parameter is that it is a label describing the state of a given system. On the other hand, the essence of a quantum observable is that it is a property of a quantum… Read More »
This blogpost is aimed to explain some portions of our paper “Dissipative preparation of phase and number squeezed states using ultracold atoms” (Phys. Rev. A 89, 013620 (2014)), authored by Gentaro Watanabe, Harri Makela, Sebastian Diehl, Markus Oberthaler and myself. At the time of the collaboration, Prof. Watanabe was based at the Asia Pacific Center… Read More »
We, physicists, are obviously not afraid. Our literature, from our notes to our papers to our books, is replete with them. We are not at all embarrassed by our seemingly wanton disregard to mathematical rigor in our mathematical acrobatics that often lead to our ill-defined or infinite-valued divergent integrals. Our enduring affair with such almost… Read More »
One of the modern books in quantum mechanics that I highly recommend to anyone is the book by the late Asher Peres—Quantum Theory: Concepts and Methods. Peres was one of the leading researchers in the foundations of quantum mechanics and a pioneer in quantum information theory. His keen understanding of quantum mechanics is clearly manifested… Read More »
Introduction We, physicists, work with our operators very differently from mathematicians. We are unencumbered by rigor and our mathematics proceeds with the motivation to forge ahead to gain insight as quickly as possible. Only later when our results are meaningful that we bother to step back and ask ourselves if our steps in reaching our… Read More »