Category: Relativity

Physics Blogging Round-Up: Gravity, Pigeonholes, Groundhogs, and Weirdness

A long-ish stretch of time, but I was basically offline for a bunch of that because I needed to finish a chapter I was asked to contribute to an academic book. So there are only four physics posts from Forbes to promote this time: — ‘The Expanse’ Is A Rare Sci-Fi Show That Gets Simulated… Continue reading Physics Blogging Round-Up: Gravity, Pigeonholes, Groundhogs, and Weirdness

Me in the Media: Two New Interviews

I’ve been slacking in my obligation to use this blog for self-promotion, but every now and then I remember, so here are two recent things where I was interviewed by other people: — I spoke on the phone to a reporter from Popular Mechanics who was writing a story about “radionics” and “wishing boxes,” a… Continue reading Me in the Media: Two New Interviews

Physics Blogging Round-Up: Two Weeks’ Worth

I forgot to do this last week, because I was busy preparing for SteelyPalooza on Saturday, but here are links to my recent physics posts over at Forbes: — What ‘Ant-Man’ Gets Wrong About The Real Quantum Realm: On the way home from the Schrödinger Sessions, I had some time to kill so I stopped… Continue reading Physics Blogging Round-Up: Two Weeks’ Worth

Back-of-the-Envelope Gravitational Which-Way

There’s a new Science Express paper on interfering clocks today, which is written up in Physics World, with comments from yours truly. The quote is from a much longer message I sent– with no expectation that it would end up as anything other than a pull quote, I might add, but I thought the background… Continue reading Back-of-the-Envelope Gravitational Which-Way

Einstein and Revolution

As mentioned over the weekend, I gave a talk last week for UCALL, part of a series on “The Radical Early 20th Century.” I talked about how relativity is often perceived as revolutionary, but isn’t really, while Einstein’s really revolutionary 1905 paper is often overlooked. And, having put the time into thinking about the subject,… Continue reading Einstein and Revolution

Science Story: Impossible Conditions

Karl Schwarzschild. Those are academic robes, not a bathrobe. Picture from Potsdam.

(When I launched the Advent Calendar of Science Stories series back in December, I had a few things in mind, but wasn’t sure I’d get through 24 days. In the end, I had more than enough material, and in fact didn’t end up using a few of my original ideas. So I’ll do a few… Continue reading Science Story: Impossible Conditions

What Does a Faster-Than-Light Object Look Like?

A dog and cat interacting with an FTL alien, as seen by the dog, with extra events added.

I exchanged a bunch of emails a week or two ago with a journalist who was working on a story involving the possibility of faster-than-light travel. He wanted me to check some statements about the relationship between FTL and causality. FTL creates problems for causality, because if you have an object moving faster than light,… Continue reading What Does a Faster-Than-Light Object Look Like?

General Relativity With Toddler Toys

The high-tech materials used to demonstrate spacetime curvature in Friday's Gen Ed class.

A couple of times last week, I mentioned on Twitter that I was going to demonstrate relativity with toddler toys and string. This was an inspiration that hit late on Thursday, when I was trying to think of a better way to explain embedding diagrams (the technical term for those stretched-rubber-sheet pictures that everybody uses… Continue reading General Relativity With Toddler Toys

Quick Interstellar Thoughts

I’m teaching a Gen Ed course on relativity this term, which means I’m spending the last few weeks of the term discussing black holes. Which, in turn, means there was no way I couldn’t use that story about Kip Thorne calculating the appearance of a black hole for the movie. Especially since I have the… Continue reading Quick Interstellar Thoughts