Book · General · Language

Correspondence principle RIP?

In reading Louisa Gilder’s book The Age of Entanglement, I was reminded of Bohr’s correspondence principle1 (originally analogy principle and also referred to as “Bohr’s magic wand”). I hadn’t thought about it much lately. Other than a few times in Lederman’s book Quantum Physics for Poets, the term wasn’t referenced in the other physics books… Continue reading Correspondence principle RIP?

Book · General · Language · Problem

Sisyphean hierarchy

In the chapter “Beyond this horizon,” Sean Carroll discusses two related problems involving properties of empty space. Before discussing the vacuum energy problem, he profiles the so-called hierarchy problem in the cosmic energy scale. It’s about the effects of virtual particles. The energy scale that characterizes the weak interactions (the Higgs field value, 246 GeV)… Continue reading Sisyphean hierarchy

General · Language · Site

Symmetry → conservation laws

In previous posts, I’ve discussed how important nature’s symmetries are to modern physics. So critical, in fact, that Nobel laureate PW Anderson wrote in his widely read 1972 article More is Different that “it is only slightly overstating the case to say that physics is the study of symmetry.” “It is increasingly clear that the… Continue reading Symmetry → conservation laws

Book · General · Language

Empty dumpty

[“Models of the quantum vacuum” series] A theoretical physicist walks into a bar. The bartender says, “What can I get you?” The physicist says, “Nothing.” The bartender gives the physicist an empty glass. The physicist says, “Thanks, that’s plenty!” Physicists take emptiness quite seriously. So-called empty space is an important area of study and research.… Continue reading Empty dumpty

Book · General · Language

Symmetry → connection field → force of nature

Here’s my take on gauge symmetry after reading about the concept (some references are listed below). There are mathematical frameworks for space, and in physics there are equations of motion for space. A mathematical framework deals with geometric and numeric objects. In everyday life we basically equate these objects with a Euclidean space using the… Continue reading Symmetry → connection field → force of nature

General · Language · Site

Eigen what?

In reading about vibrations in fields and wave functions and wave packets, some words that start with ‘e’ occurred a lot: eigenvalue, eigenvector, eigenfunction, eigenvalue equation, eigenequation [1]. I needed to refresh my understanding of the mathematical models for macroscopic and microscopic systems [2]. Everyday we are surrounded by things that vibrate when excited. Some… Continue reading Eigen what?