5 ms·
There are also 17 wallpaper groups. That always seemed like a funny number. I know it's a long shot, but is there a relation?
by d4ng 3mo ago
There are also 17 wallpaper groups. That always seemed like a funny number. I know it's a long shot, but is there a relation?
- slashdave 3mo agoFunny to who? The decimal system, for example, is a human invention.
- d4ng 3mo agoIt's a reasonably sized prime number regardless of base.
- sva_ 3mo ago> reasonably sized prime number I feel like you're alluding to something but won't say to what? Maybe something like the 'fine-tuned universe' hypothesis?
- d4ng 3mo agoActually I’m not alluding to anything specific. I just wondered whether the 17ness of wallpaper groups and fundamental particles was some sort of mapping from a related common object. Obviously a long shot as previously mentioned.
- gus_massa 3mo agoAs the article explains, counting is very hard. IMHO, I like to count the x3 colors of quarks and the x2 chirality of bosons. So I get 16*3 fermions and 1+8?+3?+1 bosons, in total 61 but the number of bosons is not a hill I will do die on. On the other extreme, there are some proposal to reduce the number of particles, in particular it makes a lot of sense to consider the electron and neutrino as a single class of particle, and the up and down quark as a single class of particle, so I guess the number goes down to 6 fermions + 4 bosons = 10? in total (I'd keep chirality, so perhaps 12+4=16?). And there are even more extreme proposals to consider quarks and leptons in a single bag of mud. In particular this was popular like twenty years ago, but the experiments disagree (IIRC by a small amount, IIRC it's not a very bad approximation) https://en.wikipedia.org/wiki/Georgi%E2%80%93Glashow_model https://en.wikipedia.org/wiki/Georgi%E2%80%93Glashow_model I tried to count the particles there and I gave up, let's say a lot. And you still have to add gravitons (and their weird cousin particles) and perhaps more than one Higgs bosons. So the number should increase in the future. And there are still ideas to add a global x2, because it would be nice if every bososn has an undiscovered fermion companion and vice versa. IIRC it's falling out of fashion because the simple versions don't agree with the experiments https://en.wikipedia.org/wiki/Supersymmetry https://en.wikipedia.org/wiki/Supersymmetry but it sounds interesting :( --- In conclusion: Don't get too attached to the number 17.
- d4ng 3mo agoVery interesting. I imagine though that the 17 model is reasonably consistent. I wonder what parallels there are with other areas of mathematics.
- gus_massa 3mo agoSomething like "17 different values of mass"[1][2][3][4][5][6][7] is a good simple model, if you allow me to put enough footnotes at the end. Different particles have different mass, and we can use the mass to classify them and call it a day and so we get 17. [1] Actually the photons and the gluons have mass=0, but nobody would confuse them. So, let's count them as different particles. (If it exist, the graviton also has mass=0 too.) [2] There is something weird with the W and Z particles, Hardcore particle physicist may claim they are the same particle and give a two hour talk about the apparent difference of mass. [3] There is something weird with the mass of neutrinos. Don't ask unless you really love linear algebra. [4] There may be details that I'm hiding on purpouse. [5] There are details that I forgot. I studied this a long time ago. [6] There are details that I never learned, perhaps more than what I expect. [7] Unknown unknowns.