Wikipedia:Reference desk/Archives/Science/2023 May 25

= May 25 =

Should I list every species in a genus?
Many articles about genera list only a few species in it, even if there are dozens of species that are classified in that genus. Should I go ahead and list every single one, or should I only do a select few? Svenard (talk) 21:14, 25 May 2023 (UTC)
 * If you have a reliable source or sources, go ahead and list them all. But if the number is ridiculous, eg >1000, it would be better to break it up into smaller subdivisions. Graeme Bartlett (talk) 03:30, 26 May 2023 (UTC)
 * No, the solution is a spinoff article, List of Foogenus species, as can be seen in Category:Lists of plant species, Category:Lists of animal species, and Category:Lists of fungal species. Please consult with the appropriate WikiProject for guidance. Please do not break up genus articles in any other way without consensus. Abductive  (reasoning) 05:06, 26 May 2023 (UTC)
 * Ghost Light (Doctor Who) is rather disjointed, but thankfully Dr Who stopped the creature in it killing everything. It was cataloguing all the various species but the list was never complete because evolution kept making new ones. NadVolum (talk) 22:21, 26 May 2023 (UTC)

Do particles in a linear particle accelerator lose speed/momentum for some reason?
Just wondering if particles in a liner accelerator are observed to lose any speed/momentum after travelling through the last E field? Byron Forbes (talk) 23:45, 25 May 2023 (UTC)
 * I think the short answer is no, but they could spread out due to repulsion. Otherwise if there is no electric or magnetic field, their inertia carries them forward at a constant velocity. But.. They could interact with a target or the end of the accelerator and lose energy. Hopefully there is enough shielding to stop anything dangerous. And once particles like neutrinos escape, they will lose energy due to leaving Earth's gravitational field, and then through the expansion of the universe. Graeme Bartlett (talk) 00:28, 27 May 2023 (UTC)
 * Not really relevant but since you mentioned them - how can a fixed speed neutrino without a frequency, lose energy? Byron Forbes (talk) 17:09, 27 May 2023 (UTC)
 * If the neutrino has mass, then it will lose energy by slowing down, and the speed is not fixed. But if it is massless, then it will still be able to lose energy by increasing its wavelength, or decreasing its frequency, as it is red shifted, but it would keep moving at the speed of light. Graeme Bartlett (talk) 04:30, 28 May 2023 (UTC)