Talk:Electromagnetic spectrum

Proposed merge of Spectral bands into Electromagnetic spectrum#Regions

same concept fgnievinski (talk) 04:45, 11 May 2022 (UTC)

• Oppose, these absolutely are not the same thing. Region, in this article, refers to the largest designation of bands of the spectrum such as X-rays. Spectral bands refers to a group of closely spaced spectral lines. The former are universal definitions and each is a continuum. The latter are specific to the material or object emitting them and are consist of a collection of discrete wavelengths. SpinningSpark 11:42, 11 May 2022 (UTC)
• Strong oppose for the same reason; these are very different concepts. I do hope that the spectral bands article gets expanded, because it's an important subject, but it's quite different from the general coverage of the EM spectrum. Mover of molehills^{move me} 14:46, 26 August 2022 (UTC)

Closing, given the uncontested objection and no support. Klbrain (talk) 15:54, 21 September 2022 (UTC)

Shortest wavelength and Planck length

An IP tried to remove the claim that the shortest wavelength possible was related to the Planck length (and deeleted the ref which might have been referencing other parts of the para). Here is another source that make that claim;

• Chris Binns, Introduction to Nanoscience and Nanotechnology, Wiley, 2021, "The Planck length, thus also defines the shortest wavelength (highest frequency) photon that can exist..."

There are many more, of varying degrees of authority on the subject. SpinningSpark 13:51, 2 October 2022 (UTC)

I don't believe that this assertion has any mainstream support. You'll see that the source you linked says "The possible missing element ...", and is is essentially saying that "if we assume some speculative condition, we might find that ...". In the currently accepted theoretical framework, a hard limit to the "maximum frequency of a photon" cannot be accommodated, so such speculation includes upending essentially all currently theories, and does not fit within them. To include any such statement (and this source is evident not an authority on quantum physics) in an article without giving the context would be silly. I suggest bringing this up at WT:PHYS if you want input from more knowledgeable people. As another note, this is essentially an article about classical electromagnetism, with barely a mention of photons. —Quondum 17:32, 3 October 2022 (UTC)

An introductory text on nanotechnology (which involves things on the scale of whole molecules) won't be a good source for anything about quantum gravity. That would be like trying to learn string theory out of a textbook on molecular biology. XOR'easter (talk) 15:41, 6 October 2022 (UTC)

Well put. The reliability of a source depends on context. Each source must be carefully weighed to judge whether it is reliable for the statement being made in the Wikipedia article and is an appropriate source for that content. Further, this source does not even seem to provide a reference, and so cannot be regarded as a secondary source.

EMR acronym

Electromagnetic radiation is introduced at the intro to article. In the body of article EMR is used for the concept on several places. When a novice reader is focused on a part of the body text and only skims the surroundings, EMR acronym's meaning might not be obvious, and search within page would not quickly bring full text to her or his attention.

I propose the change at first use to electromagnetic radiation (EMR)' in intro; if nobody opposes I'll do it in a day or two. Marjan Tomki SI (talk) 14:05, 23 December 2022 (UTC)

Go ahead. In fact, if you can repeat the full name and acronym in the body in a few places, especially deep down in the article. Constant314 (talk) 16:55, 23 December 2022 (UTC)