Talk:Faster-than-light

Who are these people?
After this edit there has been a minor skirmish, with me agreeing with the IP. I don't know if I have the same rationale as the IP who originally added the single word "cosmologist" - I don't quite understand the edit summary - but I feel the word is an improvement for the general reader.

The last edit as of this writing was by, with edit summary " we don't do that for any other person here, e.g. Martin Rees and others".

That's an "other stuff exists" argument (or, "other stuff doesn't exist" :) ). And I think we should do that for other persons. It is good that there's a reference to a paper for this particular claim, but that isn't the first appearance of the person's name.

Remember, Wikipedia is written for the general reader, and the rationale "the reader can always click the link to the person's article" is a weak justification for omitting one lousy word. I don't think it's a reasonable assumption that the general reader should have recently taken a "History of Cosmology and Mathematical Physics" course. Jeh (talk) 14:06, 12 December 2018 (UTC)


 * I agree with Headbomb's view on this. We generally do that in newspaper articles, but not in an encyclopedia. The general reader is invited to click the wikilink and read all about the linked person. Hovering over the link João Magueijo already immediately shows that he's a cosmologist. And Portuguese. DVdm (talk) 18:57, 12 December 2018 (UTC)


 * Not on my screen, it doesn't. (Chrome on Windows 10) All I see is the name of the linked article, which does not show either profession or nationality. Jeh (talk) 19:14, 12 December 2018 (UTC)
 * Firefox, IE, Chrome on Win7, Win8.1 and Win10. See Tools/Navigation popups. Very nice feature. Check it out . - DVdm (talk) 19:26, 12 December 2018 (UTC)
 * My point stands. The general reader here can't be assumed to know about that, let alone set it. Heck, there are far more unregistered readers than people with accounts - can you even set that option if you're unregistered? Jeh (talk) 19:33, 12 December 2018 (UTC)
 * My spoint is that the general reader can click the blue link and find out. After all, that's how an encyclopedia is supposed to work, encouraging the reader to wander around . - DVdm (talk) 19:40, 12 December 2018 (UTC)


 * Also, it is in general very poor form to add profession every time someone is mentioned. I'd go even further, removed the person unless that person's involvement has a direction connection to the topic. The Hartman effect is named after Hartman, you can mention Hartman. Magueijo did not discover/prove that the speed of light cannot be measured in the modern SI system. It is not important to know that he, as opposed to any of thousands of physicists, has put 'emphasis' on the speed of light being 'unmeasurable'. Headbomb {t · c · p · b} 19:42, 12 December 2018 (UTC)
 * Off-topic and very late remark here. To say "the speed of light cannot be measured in the modern SI system" is to be hugely over-impressed with SI.  The speed of light is a real thing; SI is an arbitrary human convention. --Trovatore (talk) 17:18, 1 July 2020 (UTC)

Here, not perfect, but better. Headbomb {t · c · p · b} 20:09, 12 December 2018 (UTC)
 * Definite improvement. - DVdm (talk) 21:58, 12 December 2018 (UTC)
 * I don't believe that I ever said "every time". But, for example, we expand acronyms and other abbreviations the first time they're mentioned. I don't see why a similar principle doesn't apply here. Jeh (talk) 23:26, 12 December 2018 (UTC)

Rename it as superluminosity, it sounds better
Roger Penrose uses general relativity which is superluminally wrong for predictions about action (action as defined in physics; see: Lagrangian, Hamiltonian, etc).

Relativistically, afar regions CAN recede superluminally.

In small regions no object can move superluminally. All of it's particles decay into others, and only energy BUT NO INFORMATION can travel/be emitted faster than light. — Preceding unsigned comment added by 2A02:587:4106:CEAB:CCF2:2E68:D845:51D2 (talk) 17:55, 23 May 2020 (UTC)
 * Responding to the heading, not to the text. I think a rename to superluminality might possibly be a good idea.  (Wiktionary has both superluminality and superluminosity, but the former sounds much more natural to me, as we're talking about things that are superluminal, not superluminous.)
 * The main reason I think it might be a good idea is that it's a noun, which article titles are generally supposed to be, and it comprises both communication and travel. I recorded my thoughts on this a couple years ago, at  above (presumably this will eventually get archived, but the link should work for now).
 * On the other hand it's definitely not the "common name". I could possibly live with faster-than-light travel and communication.  I've been reluctant to accept "and" titles, but sometimes they do seem to be the least bad solution. --Trovatore (talk) 19:15, 23 May 2020 (UTC)
 * I support renaming this to Superluminality. It is a bit fancy, but the daughter articles have the titles Superluminal motion and Superluminal communication, so it would be consistent with them. Jähmefyysikko (talk) 11:37, 27 August 2023 (UTC)

Unreferenced claims in GIF caption.
The cool GIF Tachyon04s.gif is captioned as
 * Because the sphere travels faster than light, the observer sees nothing until it has already passed. Then, two images appear: one of the sphere arriving (on the right) and one of it departing (on the left).

But what is the justification for this description. Indeed what is the justification for the image at all? Well other than being colorful? Johnjbarton (talk) 22:19, 12 February 2024 (UTC)

L. Gavassino and M. M. Disconzi
I removed all references to This primary ref has only two citations, one by the authors, one disputes the work. Clearly this is an example of WP:TOOSOON. Johnjbarton (talk) 21:02, 15 May 2024 (UTC)
 * Gavassino, Lorenzo; Disconzi, Marcelo (2023). "Subluminality of relativistic quantum tunneling", Phys. Rev. A 107, 032209 https://doi.org/10.1103/PhysRevA.107.032209


 * Being in the field, and not associated to the authors, to me their analysis looks not only correct but also extremely clear and simple. The criticism is inconsistent, more here: https://doi.org/10.1103/PhysRevA.107.032209 Anyway, it is probably better to wait for a bit more, as the paper is very recent. AliceHarding23 (talk) 22:14, 15 May 2024 (UTC)