Direct sum: Revision history

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curprev 14:4014:40, 3 April 2024 50.74.200.125 talk 17,279 bytes −110‎ No edit summary undo

curprev 10:2710:27, 15 March 2024 2001:620:618:5c8:2:80b3:0:a92 talk 17,389 bytes +55‎ →See also: link to generalization, in model theory undo Tag: Visual edit

curprev 22:1922:19, 9 March 2024 MadeOfAtoms talk contribs 17,334 bytes +17‎ link for "canonically isomorphic" undo Tags: Mobile edit Mobile web edit

curprev 04:1904:19, 3 February 2024 InternetArchiveBot talk contribs 17,317 bytes +203‎ Rescuing 1 sources and tagging 0 as dead.) #IABot (v2.0.9.5 undo

curprev 20:5720:57, 5 June 2023 108.176.31.30 talk 17,114 bytes −3‎ →Internal and external direct sums: fix "internal direct sum". it's nonsense to say Z_6 = \{0, 2, 4\} \oplus \{1, 3, 5\}, since the latter is not a subgroup. undo Tag: Manual revert

curprev 17:1717:17, 18 April 2023 194.95.156.119 talk 17,117 bytes +3‎ No edit summary undo Tag: Reverted

curprev 18:5218:52, 18 March 2023 David Eppstein talk contribs 17,114 bytes −182‎ WP:USERGENERATED undo

curprev 02:1202:12, 20 November 2022 BChoi33 talk contribs m 17,296 bytes −5‎ Removed a word for clarity undo

curprev 11:5511:55, 2 November 2022 MrOllie talk contribs 17,301 bytes −99‎ Reverted 1 edit by 203.124.43.2 (talk): Spam undo Tags: Twinkle Undo

curprev 04:2204:22, 26 October 2022 203.124.43.2 talk 17,400 bytes +99‎ →See also undo Tag: Reverted

curprev 00:3300:33, 24 September 2022 Ebony Jackson talk contribs 17,301 bytes −6‎ Corrected the statement about direct sum vs. direct product. undo

curprev 21:2921:29, 22 September 2022 43.231.241.65 talk 17,307 bytes −8‎ No edit summary undo

curprev 01:1101:11, 4 June 2022 ByVarying talk contribs 17,315 bytes −41‎ Emphasizing the connection with the previous sentence undo
curprev 01:0801:08, 4 June 2022 ByVarying talk contribs 17,356 bytes −1‎ Moving the example of a direct sum of abelian groups to after the definition. undo
curprev 01:0701:07, 4 June 2022 ByVarying talk contribs 17,357 bytes +125‎ Adding an explanation that technically there isn't only one "direct sum" operation, but a different operation for each type of structure. undo

curprev 09:5509:55, 29 April 2022 Hooman Mallahzadeh talk contribs m 17,232 bytes −2‎ No edit summary undo
curprev 05:4405:44, 29 April 2022 Hooman Mallahzadeh talk contribs m 17,234 bytes −4‎ Unlinking. undo
curprev 05:4105:41, 29 April 2022 Hooman Mallahzadeh talk contribs m 17,238 bytes +28‎ Linking. undo

curprev 06:5906:59, 27 April 2022 Hooman Mallahzadeh talk contribs m 17,210 bytes −12‎ →Direct sum of topological vector spaces: Redundant. undo

curprev 02:4802:48, 19 April 2022 Hellacioussatyr talk contribs 17,222 bytes −54‎ No edit summary undo Tag: 2017 wikitext editor

curprev 22:4122:41, 18 April 2022 163.118.90.85 talk 17,276 bytes +152‎ No edit summary undo Tag: Visual edit

curprev 14:3614:36, 12 April 2022 Hooman Mallahzadeh talk contribs m 17,124 bytes +14‎ →Direct sum in categories undo
curprev 14:2914:29, 12 April 2022 Hooman Mallahzadeh talk contribs m 17,110 bytes +1‎ →Direct sum in categories undo
curprev 08:0808:08, 12 April 2022 Hooman Mallahzadeh talk contribs m 17,109 bytes +26‎ →Types of direct sum: Linking. undo

curprev 14:1914:19, 11 April 2022 Hooman Mallahzadeh talk contribs m 17,083 bytes +2‎ →Internal and external direct sums: Typo. undo
curprev 13:5913:59, 11 April 2022 134.95.40.130 talk 17,081 bytes 0‎ factors -> sumands →Internal and external direct sums undo

curprev 11:4911:49, 8 April 2022 Hooman Mallahzadeh talk contribs m 17,081 bytes −2‎ No need for parenthesis. undo

curprev 19:4219:42, 21 December 2021 Mgkrupa talk contribs 17,083 bytes +283‎ →Direct sum of topological vector spaces undo
curprev 19:2819:28, 21 December 2021 Mgkrupa talk contribs 16,800 bytes +33‎ →Direct sum of topological vector spaces undo

curprev 03:3103:31, 13 December 2021 Mgkrupa talk contribs 16,767 bytes −5‎ →Direct sum of topological vector spaces undo
curprev 03:3003:30, 13 December 2021 Mgkrupa talk contribs 16,772 bytes −5‎ →Direct sum of topological vector spaces undo

curprev 06:0206:02, 9 November 2021 Ebrussel talk contribs 14,132 bytes −109‎ The paragraphs contained several errors related to a confusion between direct sums and direct products, which are defined differently, and are in general not isomorphic. When dealing with abelian groups, vector spaces, or modules, a finite direct sum is canonically isomorphic to a finite direct product. But not "identical". In the category of groups, the corresponding statement is false. Also, in the case of infinitely many objects, the two are always not isomorphic. undo Tag: 2017 wikitext editor

curprev 16:0816:08, 8 November 2021 Bourbaki77 talk contribs 14,241 bytes +28‎ added further explanation. undo Tags: Mobile edit Mobile web edit
curprev 16:0616:06, 8 November 2021 Bourbaki77 talk contribs 14,213 bytes −92‎ I erased an erroneous statement that said an ordered pair is the Cartesian product. The Cartesian product is the set of all ordered pairs with elements from two sets. The direct sum is the Cartesian product with the additional appropriate algebraic structure. undo Tags: Mobile edit Mobile web edit

curprev 19:5719:57, 30 July 2021 Mgkrupa talk contribs m 14,305 bytes +3‎ Fix undo
curprev 19:5719:57, 30 July 2021 Mgkrupa talk contribs 14,302 bytes +55‎ Clarification undo
curprev 13:2713:27, 30 July 2021 2001:b011:e001:31c2:4996:b21e:d154:e384 talk 14,247 bytes −1‎ →Direct sum of group representations undo Tag: Visual edit

curprev 02:2402:24, 26 July 2021 Omaredabed talk contribs m 14,248 bytes +3‎ →Direct sum of group representations: minor typo undo Tag: Visual edit

curprev 22:4722:47, 23 July 2021 Mgkrupa talk contribs m 14,245 bytes +18‎ Added {{main|}} undo
curprev 22:3222:32, 23 July 2021 Mgkrupa talk contribs 14,227 bytes +520‎ Added information undo
curprev 22:1422:14, 23 July 2021 Mgkrupa talk contribs 13,707 bytes +333‎ Added {{visible anchor|}} and copy editing to make this article more compliant with Wikipedia:Manual of Style/Accessibility. Replaced some Unicode symbols with LaTeX. No information was added, removed, or changed. undo

curprev 13:3713:37, 28 May 2021 91.10.179.113 talk 13,374 bytes +3‎ Changed matrix 'see also' to matrix addition. undo
curprev 11:3211:32, 28 May 2021 137.226.19.48 talk 13,371 bytes +75‎ Improved direct sum of matrices. undo
curprev 11:2111:21, 28 May 2021 137.226.19.48 talk 13,296 bytes +423‎ Added direct sum of matrices. undo

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