The direct sum is an operation between structures in abstract algebra, a branch of mathematics. It is defined differently but analogously for different...
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In abstract algebra, the direct sum is a construction which combines several modules into a new, larger module. The direct sum of modules is the smallest...
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In mathematics, a group G is called the direct sum of two normal subgroups with trivial intersection if it is generated by the subgroups. In abstract algebra...
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Product of rings (redirect from Direct sum of rings)
Πi∈I Ri coincides with the direct sum of the additive groups of the Ri. In this case, some authors call R the "direct sum of the rings Ri" and write ⊕i∈I...
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The direct sum of two matrices is the diagonal matrix where the top-left and bottom-right corners of the matrix fill the two given matrices, and where...
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Semidirect product (redirect from Semi-direct sum)
group theory, the concept of a semidirect product is a generalization of a direct product. It is usually denoted with the symbol ⋉. There are two closely...
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Graded vector space (redirect from Direct sum of graded vector spaces)
grading or gradation, which is a decomposition of the vector space into a direct sum of vector subspaces, generally indexed by the integers. For "pure" vector...
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Block matrix (section Direct sum)
dimensions). Note that any element in the direct sum of two vector spaces of matrices could be represented as a direct sum of two matrices. A block diagonal matrix...
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Disjoint union (topology) (redirect from Direct sum (topology))
mathematics, the disjoint union (also called the direct sum, free union, free sum, topological sum, or coproduct) of a family of topological spaces is...
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Matrix addition (redirect from Direct sum (Matrix))
Matrix multiplication Vector addition Direct sum of matrices Kronecker sum Elementary Linear Algebra by Rorres Anton 10e p53 Lipschutz...
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Antiunitary operator (section Decomposition of an antiunitary operator into a direct sum of elementary Wigner antiunitaries)
a direct sum of unitaries acting on 1-dimensional complex spaces (eigenspaces), but an antiunitary operator may only be decomposed into a direct sum of...
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Hilbert space (redirect from Square-summable sequence)
canonically isomorphic to the direct sum of Vi. In this case, H is called the internal direct sum of the Vi. A direct sum (internal or external) is also...
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a combination of algebraic objects Direct sum of groups Direct sum of modules Direct sum of permutations Direct sum of topological groups Einstein summation...
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each subgroup gives rise to a quotient group. Subgroups, quotients, and direct sums of abelian groups are again abelian. The finite simple abelian groups...
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In combinatorics, the skew sum and direct sum of permutations are two operations to combine shorter permutations into longer ones. Given a permutation...
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Vector bundle (redirect from Direct sum of vector bundles)
Whitney sum (named for Hassler Whitney) or direct sum bundle of E and F is a vector bundle E ⊕ F over X whose fiber over x is the direct sum Ex ⊕ Fx of...
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the direct sum of representations please refer to the section on direct sums of representations. A representation is called isotypic if it is a direct sum...
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notions of direct product in mathematics. In the context of abelian groups, the direct product is sometimes referred to as the direct sum, and is denoted...
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Coproduct (redirect from Sum (category theory))
categorical sum, is a construction which includes as examples the disjoint union of sets and of topological spaces, the free product of groups, and the direct sum...
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Complemented subspace (redirect from Topological direct sum)
the algebraic direct sum by requiring certain maps be continuous; the result retains many nice properties from the operation of direct sum in finite-dimensional...
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mathematics, a topological group G {\displaystyle G} is called the topological direct sum of two subgroups H 1 {\displaystyle H_{1}} and H 2 {\displaystyle H_{2}}...
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illustration of the tensor product of algebras, and as an illustration of the direct sum of algebras. The split-biquaternions have been identified in various ways...
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Vector space (section Direct product and direct sum)
similar to the corresponding statements for groups. The direct product of vector spaces and the direct sum of vector spaces are two ways of combining an indexed...
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it is the direct sum of simple (irreducible) submodules. For a module M, the following are equivalent: M is semisimple; i.e., a direct sum of irreducible...
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representation) is a linear representation of a group or an algebra that is a direct sum of simple representations (also called irreducible representations). It...
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Linear complex structure (section Direct sum)
This ordering is more natural if one thinks of the complex space as a direct sum of real spaces, as discussed below. The data of the real vector space...
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to a direct sum of copies of the ring R. These are the modules that behave very much like vector spaces. Projective Projective modules are direct summands...
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Cofiniteness (section Direct sum)
sets, particularly on infinite products, as in the product topology or direct sum. This use of the prefix "co" to describe a property possessed by a set's...
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on C, Direct sum There is an isomorphism h from B to the direct sum of A and C, such that hq is the natural injection of A into the direct sum, and r...
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x {\displaystyle x} and every e ∈ E x , {\displaystyle e\in E_{x},} a direct sum decomposition of T X ( x ) E {\displaystyle T_{X(x)}E} into two linear...
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