LOL, I’m the exact opposite. I’ll listen to sports podcasts, read sports articles, argue about NBA shit… and never watch a single game all year.
A nearby stretch of road was nicely repaved, restriped, and new dots glued on. The blue dots were very obvious, being new and bright and shiny, and I realized I didn’t know their purpose. I remembered to Google them up this morning: they are there to denote fire hydrants right opposite them at the curb. The blueness makes it easier for firefighters to quickly find a hydrant even if it’s foggy, smoky, trafficky, or chaotic. So now I know.
We don’t actually know that. If spacetime is quantized, and if it’s quantized in such a way that there is such a thing as a smallest measurable unit of length, then our best guess is that that smallest length is somewhere in the general vicinity of the Planck length. But that’s a lot of qualifiers, and we’re pretty much in the dark on all of them. We won’t know the answers of any of those questions at least until we develop a quantum theory of gravity, which we aren’t really even close to.
Note that, for example, the Planck mass is nowhere near the smallest possible mass. It’s at least 1029 times larger than the neutrino mass.
Yeah, some of the Planck units are incredibly large, and we know (at least, so far as we know anything in physics) that the Planck speed is the largest possible speed. And some of them are incredibly small, and we know (same caveats) that the Planck angular momentum is the smallest possible angular momentum. But the Planck mass is about the mass of a bacterium: Incredibly large for a subatomic particle, but incredibly small for a black hole. And the Planck momentum is about the momentum of a running housecat.
And wouldn’t we love to see a black hole small enough that it had measurable Hawking radiation, so we could test what happens when General Relativity and Quantum Mechanics bump heads.
meaningless mathematical masturbation = m³
Oh, yeah, back when the LHC was firing up and some folks were worried about it producing black holes, I said that it was the second-most-interesting thing it could possibly do (and still wasn’t any actual risk).
The most interesting, of course, was something we hadn’t expected at all.
Sadly, all it found was the Higgs and nothing else, which was the least interesting possible outcome.
Great post. Was that really the only new science? Is it still going?
I mean, it’s refined a lot of things, brought down the error bars on a lot of numbers, that sort of thing. That’s an underappreciated part of science, and it’s earned its keep fairly. But nothing revolutionary.
Here’s one that still delights me: wombats produce cube-shaped droppings because the elasticity of their intestines varies along the length, and the shape conveniently keeps the scat from rolling away when they mark territory.
Granted, many things in theoretical physics cannot be tested or measured in a laboratory. Heck, the term “length” itself applied to something that small is questionable.
Usually, that’s a moving target: There are things that can’t be tested in the lab right now, but as technology improves, or someone comes up with a clever new experiment, they can be. And there is, in that sense, a smallest distance that can be measured by physics (using current technology). But that current, technological, limit is far, far away from the Planck length.
On the other hand, there are also some things in physics that (so far as we know) simply can’t be measured at all, no matter how far technology advances.
If you’re referring to the example of a particle’s motion and position simultaneously, it isn’t that we can’t measure it but that there aren’t two separate values to measure: a quantum particle doesn’t have an absolute motion AND an absolute position. So it’s not merely a case of nature holding out on us, it’s that there’s no “there” there.
Now you mention it, I see that the English language is in dire need of the word “shorth” for such minute …huh… shorths. I hereby declare this word coined.
Now I am curious. Could you give some examples that are understandable to laypeople?
I don’t think that is what Chronos was refering to: a limit on the precision of two simultaneous measurements of correlated phenomena is not the same as “can’t be measured at all”. I may be wrong, and of course I am not writing in his name.
The uncertainty principle would be one example of what I’m referring to, though it’s a philosophical question whether the precise position and velocity are even something that actually exists at all. Another example would be the absolute phase of any quantum mechanical wavefunction: Relative phases certainly exist, and are responsible for a great many quantum effects, but absolute phase is completely inaccessible.
Four of the five original members of the Zombies are still alive.
Alive or undead?
As of November 18, the Voyageur 1 spacecraft (launched 49 years ago) will be one light-day from Earth. Only about 1500 more “days” to reach the nearest star.
That’s astonishing and humiliating at once.