WorldCat Identities

Kubert, Daniel S.

Works: 3 works in 18 publications in 2 languages and 450 library holdings
Roles: Author
Classifications: QA247, 512.74
Publication Timeline
Most widely held works by Daniel S Kubert
Modular units by Daniel S Kubert( Book )

16 editions published in 1981 in English and German and held by 402 WorldCat member libraries worldwide

In the present book, we have put together the basic theory of the units and cuspidal divisor class group in the modular function fields, developed over the past few years. Let i) be the upper half plane, and N a positive integer. Let r(N) be the subgroup of SL (Z) consisting of those matrices == 1 mod N. Then r(N)\i) 2 is complex analytic isomorphic to an affine curve YeN), whose compactifi cation is called the modular curve X(N). The affine ring of regular functions on yeN) over C is the integral closure of C[j] in the function field of X(N) over C. Here j is the classical modular function. However, for arithmetic applications, one considers the curve as defined over the cyclotomic field Q(JlN) of N-th roots of unity, and one takes the integral closure either of Q[j] or Z[j], depending on how much arithmetic one wants to throw in. The units in these rings consist of those modular functions which have no zeros or poles in the upper half plane. The points of X(N) which lie at infinity, that is which do not correspond to points on the above affine set, are called the cusps, because of the way they look in a fundamental domain in the upper half plane. They generate a subgroup of the divisor class group, which turns out to be finite, and is called the cuspidal divisor class group
Zeen( )

in English and held by 1 WorldCat member library worldwide

Groups on two generators <(g), (h)> with (h) spanning all cosets of (g) by Daniel S Kubert( )

1 edition published in 1969 in English and held by 1 WorldCat member library worldwide

Audience Level
Audience Level
  Kids General Special  
Audience level: 0.70 (from 0.62 for Groups on ... to 0.70 for Modular un ...)

WorldCat IdentitiesRelated Identities
Modular units
Alternative Names
Daniel Kubert American mathematician

Daniel Kubert Amerikaans wiskundige (1947-2010)

Daniel Kubert matemàtic estatunidenc

Daniel Kubert matemático estadounidense

Daniel Kubert matematico statunitense

Kubert, D.

English (17)

German (1)