Cleaning up after Matt Parker 3 ▲ And now it’s all this 58 days ago · Tech · hide · Fediverse post [Equations in this post may not look right (or appear at all) in your RSS reader. Go to the original article to see them rendered properly.] This video Matt Parker posted a couple of days ago really pissed me off: It’s cheating to say that a result arrived at through classical mechanics—in this case, that 12mv2 is the kinetic energy of a particle—is wrong because it’s only an approximation to relativistic physics. Of course that’s the case, and I swore at my phone when the “reveal” came. By the end of the video, though, I had calmed down because I knew I could put together a quick post of my own by rewriting the infinite series equation he derived in a better form. Also, I could provide a general expression for the individual terms. Let’s start with this result: that the kinetic energy of a particle (including relativistic effects) is mc2(γ−1) where m is the mass of the particle, c is the speed of light, and γ=11−v2c2 is the Lorentz factor, with v as the velocity of the particle. The… Commenting on Bubbles has been removed. Why? If you want to talk about this post, write to the author, use the comments on their blog if it has them, or reply with a "RE:" post on your own blog. Suggestions? feedback@bubbles.town