Last time, I showed you how you could construct a photon, a light particle, in a configuration of mirrors called a ring cavity. This time I’ll show you that sometimes, you can’t make just one particle—they only come in pairs. And sometimes, the notion of a particle doesn’t make any sense at all. (This post relies heavily on last week’s post, so if you haven’t read that, I recommend you do so.) Disclaimer: What I’m about to describe is only the simplest case, and I make simplifications for the sake of exposition. It is possible to capture and manipulate
waves
Physics / Quantum Mechanics / Science And Math
What’s in a Particle?
If you’ve read or heard anything about quantum mechanics, you’ve heard the phrase “particle-wave duality.” The common wisdom is that this means that particles sometimes behave like waves and sometimes behave like particles. And although this is right, it’s a bit misleading. The truth is: Everything is always a wave. It’s just that waves can be made to behave like particles. To see what I mean, let’s actually show how one can make a set of waves behave like a particle. Specifically, let’s show how a set of light waves can be made to behave like a photon, a light particle.
Condensed Matter / cosmology / Physics / etc.
BICEP2, Primordial Gravity Waves, and Cosmic Inflation
“Like the microscopic strands of DNA that predetermine the identity of a macroscopic species and the unique properties of its members, the modern look and feel of the cosmos was writ in the fabric of its earliest moments, and carried relentlessly through time and space. We feel it when we look up. We feel it when we look down. We feel it when we look within.” ~Niel Degrasse Tyson There was some very big news today! If you haven’t already heard, the BICEP2 research group at Harvard has found evidence of ancient gravitational waves in the sky. A lot
Mathematics / Physics / Quantum Mechanics / etc.
Resolution, Fourier Analysis, and The Heisenberg Uncertainty Principle
All the effects of nature are only mathematical results of a small number of immutable laws. ~Pierre-Simon Laplace In my discussion last time (corrections here), I discussed how there is a physical limit to how good a recording can sound, whether vinyl or digital. There is a more fundamental limit, however, that I glossed over—a limit that depends not on atoms or compression techniques, but on pure mathematics. This limit was partially discovered by Jean Baptiste Joseph Fourier, and the method we will discuss bears his name. The Superposition Principle Before we discuss Fourier’s discovery, let’s take a brief
Physics / Quantum Mechanics / Science And Math
The Dice Are Loaded: Probability Waves
God does not play dice ~Albert Einstein Einstein, stop telling God what to do! ~Niels Bohr This is part three of a multi-part series on quantum mechanics. In part one, I discussed how we discovered that light is both a wave and a particle. The dual nature of light suggests that massive particles like electrons might be waves too. In part two, I gave a theoretical underpinning to the dual nature of electrons: treating electrons as waves completes the Bohr Model of the atom and explains the Rydberg Formula. However, legendary physicist Richard Feynman once said: It doesn’t matter