1.

Record Nr.

UNINA9910697497603321

Autore

Headd Brian

Titolo

Do business definition decisions distort small business research results? [[electronic resource] ] : an Office of Advocacy working paper / / Brian Headd and Radwan Saade

Pubbl/distr/stampa

[Washington, D.C.] : , : SBA Office of Advocacy, , [2008]

Descrizione fisica

2 unnumbered pages : digital, PDF file

Collana

Small business research summary ; ; no. 330

Altri autori (Persone)

SaadeRadwan

Soggetti

Business enterprises - United States

Small business - United States - Growth

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Note generali

Title from title screen (viewed on Aug. 20, 2008).

"August 2008."



2.

Record Nr.

UNINA9910793890203321

Autore

Joyce Dominic D.

Titolo

Algebraic geometry over C[infinity]-rings / / Dominic Joyce

Pubbl/distr/stampa

Providence, RI : , : American Mathematical Society, , [2019]

©2019

ISBN

1-4704-5336-3

Descrizione fisica

1 online resource (152 pages) : illustrations

Collana

Memoirs of the American Mathematical Society, , 0065-9266 ; ; number 1256

Classificazione

58A4014A2046E2551K10

Disciplina

516.3/6

Soggetti

Geometry, Algebraic

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Note generali

"July 2019, volume 260, number 1256 (third of 5 numbers)."

Nota di bibliografia

Includes bibliographical references and index.

Nota di contenuto

C[infinity]-rings -- The C[infinity]-ring C[infinity](X) of a manifold X -- C[infinity]-ringed spaces and C[infinity]-schemes -- Modules over C[infinity]-rings and C[infinity]-schemes -- C[infinity]-stacks -- Deligne-Mumford C[infinity]-stacks -- Sheaves on Deligne-Mumford C[infinity]-stacks -- Orbifold strata of C[infinity]-stacks.

Sommario/riassunto

"If X is a manifold then the R-algebra C[infinity](X) of smooth functions C : X [right arrow] R is a C[infinity]-ring. That is, for each smooth function f : Rn [right arrow] R there is an n-fold operation ]Phi]f : C[infinity](X)n [right arrow] C[infinity](X) acting by [Phi]f : (c1, . . . , cn) [right arrow] f(c1, . . . , cn), and these operations [Phi]f satisfy many natural identities. Thus, C[infinity](X) actually has a far richer structure than the obvious R-algebra structure. We explain the foundations of a version of algebraic geometry in which rings or algebras are replaced by C[infinity]-rings. As schemes are the basic objects in algebraic geometry, the new basic objects are C[infinity]-schemes, a category of geometric objects which generalize manifolds, and whose morphisms generalize smooth maps. We also study quasicoherent sheaves on C[infinity]-schemes, and C[infinity]-stacks, in particular Deligne- Mumford C[infinity]-stacks, a 2-category of geometric objects generalizing orbifolds. Many of these ideas are not new: C[infinity]-rings and C[infinity]-schemes have long been part of synthetic differential geometry. But we develop them in new directions. In Joyce (2014, 2012, 2012 preprint), the author uses these tools to define d-



manifolds and d-orbifolds, 'derived' versions of manifolds and orbifolds related to Spivak's 'derived manifolds' (2010)"--