Talk:Eigenvalues and eigenvectors

message: My guess, it is from the early works of linear algebra and eigenvalues and eigenvectors arising from analyzing wave equations, where lambda would be used for wavelength, and different modes (eigenvectors) would correspond to various special solutions that can be linearly combined? Then set in stone when essentially same was done to Schrodinger's equation in Hamilton formulation of QM. Unfortunatly it is hard to find sources where the lambda symbol become popular for use for eigenvalues and what is the real origin of this popularity. 2A02:168:2000:5B:94CB:836:78C3:226E (talk) 12:17, 24 June 2020 (UTC)
thread_title:  Historical origin of the use of lambda for eigenvalues? 

message: Wikipedia is intended to be a general-purpose encyclopaedia.  This marks a contrast with a technical manual for the already expert practitioner.
But in this article, the lead is deeply technical, followed by a section "formal definition" which likewise is deeply technical.  The intended readership is left floundering in meaninglessness.
We need the article to arrive very quickly at a general overview.  The section "overview", especially with its pictorial illustration, would be much better placed earlier.  So I propose reversing the order of "formal definition" and "overview".  (Perhaps other minor adjustments might become necessary, but they are second-order effects.)  Unless there is serious objection, I propose doing this in about a week (21 June 2021).  Feline Hymnic (talk) 16:12, 14 June 2021 (UTC)
replies: text: I disagree.  The definition section says little more than what is in the lead, but in more precise mathematical terms. The overview section describes applications which should be preceded by a formal definition.—Anita5192 (talk) 16:33, 14 June 2021 (UTC)
thread_title:  Suggested re-ordering 

message: The discussion about zero vector being an eigenvector was confusing. The source [1] cited said nothing of the kind, and there is a general consensus among mathematicians consistent with the rest of the article.
I've actually checked the reference provided and there is nothing about eigenvectors at the referenced page (p. 77). The chapter about eigenvectors from that book is actually freely available [link ] and it nicely explains the philosophy of eigenvectors as invariant sub-spaces. All the definitions in the book are consistent with excluding the zero vector as an eigenvector.
[1] Axler, Sheldon (18 July 2017), Linear Algebra Done Right (3rd ed.), Springer, p. 77, ISBN (Links to an external site.) 978-3-319-30765-7  — Preceding unsigned comment added by Ormulogun (talk • contribs) 15:56, 10 February 2022 (UTC)
thread_title:  Zero vector as an eigenvector removed. 

message: Was reading the article, and the line starting "Equation (2) has a nonzero solution..." and couldn't find the referenced equation.
The equation numbers are on the extreme far right side of the page, and as such are a) difficult to find, and b) difficult to associate with their equation when several equations are listed vertically. It's especially a problem with this article because all equations are fairly short.
Is there some way of moving the equation reference numbers closer to the actual equations, on pages where the equations are short?
(I'd venture to guess that nearly all equations in all math pages are short, relative to the width of modern monitors.)  — Preceding unsigned comment added by 64.223.87.47 (talk) 20:52, 22 August 2022 (UTC)
replies: text: As far as I know, there is no way to adjust the way this feature positions the equation numbers. If you are viewing on a large screen, you could make the window narrower.—Anita5192 (talk) 23:09, 22 August 2022 (UTC)
thread_title:  Equation numbers are difficult to find. 

message: Some sections in the article use bars for the determinant, even when applied to a symbolic expression, i.e.
:  | A - \lambda I |  rather than  \det(A-\lambda I) .
This is IMO wrong; vertical bars for determinant is a shorthand in which the bars replace the parenthesis delimiting an matrix given in terms of its elements:
:  \begin{vmatrix} a & b \\ c & d \end{vmatrix} = \det \begin{pmatrix} a & b \\ c & d \end{pmatrix} .
130.243.94.123 (talk) 12:39, 21 August 2023 (UTC)
replies: text: — Anita5192 (talk) 15:11, 21 August 2023 (UTC)
thread_title:  Notation for determinant