3 ms·
I remember when I first learned about absolute zero, ages ago, and thought “if it’s unreachable, it must be like an asymptote…but that would mean we’re measurin
by evincarofautumn 8y ago
I remember when I first learned about absolute zero, ages ago, and thought “if it’s unreachable, it must be like an asymptote…but that would mean we’re measuring temperature ‘upside-down’…”
Much later, I learned about that very thing (1/T, “thermodynamic beta”) while wikiwalking after hearing about the concept of negative temperature. Then I fell into a rabbit-hole wondering if we also measure speed upside-down in that way, since you can’t accelerate to light-speed. And indeed, when you’re talking about relativistic effects, units of time per distance can be more illustrative sometimes than our intuition of distance per time.
- wnoise 8y agoFor speed we don't measure it "upside down", no. But there is another transformation: "rapidity", which does add linearly (at least for one spatial dimension) and goes to infinity when velocity goes to c. https://en.wikipedia.org/wiki/Rapidity https://en.wikipedia.org/wiki/Rapidity
- evincarofautumn 8y agoWell no, I just meant that sometimes working in inverse units makes things easier to understand than the “intuitive” units you use in daily life. “Time per distance” helped me personally get a better intuitive sense of time dilation and length contraction. I hadn’t heard of rapidity before, but it’s really interesting, and makes sense after some musing—thanks!