Category: Relativity

Why Does E=mc2? by Brian Cox and Jeff Forshaw

I want to like this book more than I do. As a general matter, this is exactly the sort of science book we need more of. As you can probably guess from the title, Why Does E=mc2? sets out to explain Einstein’s theory of relativity, and does an excellent job of it. It presents a… Continue reading Why Does E=mc2? by Brian Cox and Jeff Forshaw

Accelerated Twins: The Answer

Yesterday’s post on a variation of the “Twin Paradox” with both twins accelerating was very successful– 337 people voted in the first poll question, as of a little before 9am, and the comments to the original post are full of lively discussion. That’s awesome. I wish I could take credit for it, but the problem… Continue reading Accelerated Twins: The Answer

Physics Quiz: Accelerated Twins

Just about everybody has heard of the Twin Paradox in relativity: one twin becomes as astronaut and sets off for Alpha Centauri, the other remains on Earth at mission control. Thanks to time dilation, the two age at different rates, and the one who made the trip out and back ends up younger than the… Continue reading Physics Quiz: Accelerated Twins

Zitterbewegung!

One of the few sad things about the recent American domination of physics (says the American physicist) is that new physical phenomena are now mostly given boring, prosaic American English names. Don’t get me wrong, I like being able to pronounce and interpret new phenomena, but when the pre-WWII era of European dominance faded away,… Continue reading Zitterbewegung!