Strassen’s 2×2 matrix multiplication algorithm: a conceptual perspective

The main purpose of this paper is pedagogical. Despite its importance, all proofs of the correctness of Strassen’s famous 1969 algorithm to multiply two 2 × 2 matrices with only seven multiplications involve some basis-dependent calculations such as explicitly multiplying specific 2 × 2 matrices, ex...

Celý popis

Uloženo v:
Podrobná bibliografie
Vydáno v:Annali dell'Università di Ferrara. Sezione 7. Scienze matematiche Ročník 65; číslo 2; s. 241 - 248
Hlavní autoři: Ikenmeyer, Christian, Lysikov, Vladimir
Médium: Journal Article
Jazyk:angličtina
Vydáno: Milan Springer Milan 01.11.2019
Springer Nature B.V
Témata:
ISSN:0430-3202, 1827-1510
On-line přístup:Získat plný text
Tagy: Přidat tag
Žádné tagy, Buďte první, kdo vytvoří štítek k tomuto záznamu!
Popis
Shrnutí:The main purpose of this paper is pedagogical. Despite its importance, all proofs of the correctness of Strassen’s famous 1969 algorithm to multiply two 2 × 2 matrices with only seven multiplications involve some basis-dependent calculations such as explicitly multiplying specific 2 × 2 matrices, expanding expressions to cancel terms with opposing signs, or expanding tensors over the standard basis, sometimes involving clever simplifications using the sparsity of tensor summands. This makes the proof nontrivial to memorize and many presentations of the proof avoid showing all the details and leave a significant amount of verifications to the reader. In this note we give a short, self-contained, basis-independent proof of the existence of Strassen’s algorithm that avoids these types of calculations. We achieve this by focusing on symmetries and algebraic properties. Our proof can be seen as a coordinate-free version of the construction of Clausen from 1988, combined with recent work on the geometry of Strassen’s algorithm by Chiantini, Ikenmeyer, Landsberg, and Ottaviani from 2016.
Bibliografie:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
ISSN:0430-3202
1827-1510
DOI:10.1007/s11565-019-00318-1