Algorithms and Time Warps
I suppose before I go much further with this I need to set out some kind of a statement of purpose for this blog. There are lots of topics and ideas that I think about, and occasionally one of these …...
View ArticleSymmetry and Newton’s law of motion
Physicists say that one of the great underlying and unifying ideas in modern theoretical physics is symmetry. Each physical theory is said to “obey” or “respect” a set of symmetries, and the symmetries...
View ArticleDimensions
Some people seem to be very fascinated with the concept of dimensions. The ideas of “alternate dimensions” abound in science fiction, not to mention pseudoscience. For instance, I recently came across...
View ArticleNumerically modeling the expansion of the universe
Most people are familiar with the standard model of cosmology: the universe (or at least the part of it we can see) began in a Big Bang and has been expanding and cooling off ever since. Mathematical...
View ArticleRotations and Infinitesimal Generators
In this post I’d like to talk about rotations in three-dimensional space. As you can imagine, rotations are pretty important transformations! They commonly show up in physics as an example of a...
View ArticleDark energy and the cosmic horizon
In a previous post, I wrote about using numerical integration to calculate how the universe expands over time. It turned out that dark energy is making the expansion of the universe speed up, and (we...
View ArticleE = mc² is only half the story
I’m sure you’ve seen the equation many times. Probably the best-known equation in physics, it represents both a straightforward mathematical relationship and a deep physical principle. But did you know...
View ArticleNested Complex Numbers
As many of us learn in school, we can invent the complex numbers by starting with the real numbers, then simply “making up” a brand-new number, called , which is not equal to any real number, and whose...
View ArticleGreg Egan’s Orthogonal: Alternate Physics, Familiar Politics
Science fiction works are commonly classified on a spectrum ranging from “soft” to “hard”. The distinction lies in the fiction’s attitude toward the physics (or other science) involved in the story. In...
View ArticleThree levels of locality in quantum physics
Locality seems to be a deep principle of physics. It’s the idea that what happens at any given place in the universe doesn’t (directly) depend on things happening in other places far away, but only on...
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