|
Waldspurger Formula
In representation theory of mathematics, the Waldspurger formula relates the special values of two ''L''-functions of two related admissible irreducible representations. Let be the base field, be an automorphic form over , be the representation associated via the Jacquet–Langlands correspondence with . Goro Shimura (1976) proved this formula, when k = \mathbb and is a cusp form; Günter Harder made the same discovery at the same time in an unpublished paper. Marie-France Vignéras (1980) proved this formula, when k = \mathbb and is a newform. Jean-Loup Waldspurger, for whom the formula is named, reproved and generalized the result of Vignéras in 1985 via a totally different method which was widely used thereafter by mathematicians to prove similar formulas. Statement Let k be a number field, \mathbb be its adele ring, k^\times be the subgroup of invertible elements of k, \mathbb^\times be the subgroup of the invertible elements of \mathbb, \chi, \chi_1, \chi_2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Representation Theory
Representation theory is a branch of mathematics that studies abstract algebraic structures by ''representing'' their elements as linear transformations of vector spaces, and studies modules over these abstract algebraic structures. In essence, a representation makes an abstract algebraic object more concrete by describing its elements by matrices and their algebraic operations (for example, matrix addition, matrix multiplication). The theory of matrices and linear operators is well-understood, so representations of more abstract objects in terms of familiar linear algebra objects helps glean properties and sometimes simplify calculations on more abstract theories. The algebraic objects amenable to such a description include groups, associative algebras and Lie algebras. The most prominent of these (and historically the first) is the representation theory of groups, in which elements of a group are represented by invertible matrices in such a way that the group operatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center (algebra And Category Theory)
The term center or centre is used in various contexts in abstract algebra to denote the set of all those elements that commutative operation, commute with all other elements. * The center of a group ''G'' consists of all those elements ''x'' in ''G'' such that ''xg'' = ''gx'' for all ''g'' in ''G''. This is a normal subgroup of ''G''. * The similarly named notion for a semigroup is defined likewise and it is a subsemigroup. * The center (ring theory), center of a ring (mathematics), ring (or an associative algebra) ''R'' is the subset of ''R'' consisting of all those elements ''x'' of ''R'' such that ''xr'' = ''rx'' for all ''r'' in ''R''., Exercise 22.22 The center is a commutative ring, commutative subring of ''R''. * The center of a Lie algebra ''L'' consists of all those elements ''x'' in ''L'' such that [''x'',''a''] = 0 for all ''a'' in ''L''. This is an ideal (ring theory), ideal of the Lie algebra ''L''. See also *Centralizer and normalizer *Center (category theory) Refere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Representation Theory
Representation theory is a branch of mathematics that studies abstract algebraic structures by ''representing'' their elements as linear transformations of vector spaces, and studies modules over these abstract algebraic structures. In essence, a representation makes an abstract algebraic object more concrete by describing its elements by matrices and their algebraic operations (for example, matrix addition, matrix multiplication). The theory of matrices and linear operators is well-understood, so representations of more abstract objects in terms of familiar linear algebra objects helps glean properties and sometimes simplify calculations on more abstract theories. The algebraic objects amenable to such a description include groups, associative algebras and Lie algebras. The most prominent of these (and historically the first) is the representation theory of groups, in which elements of a group are represented by invertible matrices in such a way that the group operatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shimura Correspondence
In number theory, the Shimura correspondence is a correspondence between modular forms ''F'' of half integral weight ''k''+1/2, and modular forms ''f'' of even weight 2''k'', discovered by . It has the property that the eigenvalue of a Hecke operator ''T''''n''2 on ''F'' is equal to the eigenvalue of ''T''''n'' on ''f''. Let f be a holomorphic cusp form with weight (2k+1)/2 and character \chi . For any prime number ''p'', let :\sum^\infty_\Lambda(n)n^=\prod_p(1-\omega_pp^+(\chi_p)^2p^)^\ , where \omega_p's are the eigenvalues of the Hecke operators T(p^2) determined by ''p''. Using the functional equation of L-function, Shimura showed that :F(z)=\sum^\infty_ \Lambda(n)q^n is a holomorphic modular function with weight ''2k'' and character \chi^2 . Shimura's proof uses the Rankin-Selberg convolution of f(z) with the theta series \theta_\psi(z)=\sum_^\infty \psi(n) n^\nu e^ \ () for various Dirichlet characters \psi then applies Weil's converse theorem. See also * Theta cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eigenform
In mathematics, an eigenform (meaning simultaneous Hecke eigenform with modular group SL(2,Z)) is a modular form which is an eigenvector for all Hecke operators ''Tm'', ''m'' = 1, 2, 3, .... Eigenforms fall into the realm of number theory, but can be found in other areas of math and science such as analysis, combinatorics, and physics. A common example of an eigenform, and the only non-cuspidal eigenforms, are the Eisenstein series. Another example is the Δ Function. In second-order cybernetics, eigenforms are an example of a self-referential system.Kauffman, L. H. (2003). Eigenforms: Objects as tokens for eigenbehaviors. Cybernetics and Human Knowing, 10(3/4), 73-90. Normalization There are two different normalizations for an eigenform (or for a modular form in general). Algebraic normalization An eigenform is said to be normalized when scaled so that the ''q''-coefficient in its Fourier series is one: :f = a_0 + q + \sum_^\infty a_i q^i wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atkin–Lehner Theory
In mathematics, Atkin–Lehner theory is part of the theory of modular forms describing when they arise at a given integer ''level'' ''N'' in such a way that the theory of Hecke operators can be extended to higher levels. Atkin–Lehner theory is based on the concept of a newform, which is a cusp form 'new' at a given ''level'' ''N'', where the levels are the nested congruence subgroups: :\Gamma_0(N) = \left\ of the modular group, with ''N'' ordered by divisibility. That is, if ''M'' divides ''N'', Γ0(''N'') is a subgroup of Γ0(''M''). The oldforms for Γ0(''N'') are those modular forms ''f(τ)'' of level ''N'' of the form ''g''(''d τ'') for modular forms ''g'' of level ''M'' with ''M'' a proper divisor of ''N'', where ''d'' divides ''N/M''. The newforms are defined as a vector subspace of the modular forms of level ''N'', complementary to the space spanned by the oldforms, i.e. the orthogonal space with respect to the Petersson inner product. The Hecke operators, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whittaker Function
In mathematics, a Whittaker function is a special solution of Whittaker's equation, a modified form of the confluent hypergeometric equation introduced by to make the formulas involving the solutions more symmetric. More generally, introduced Whittaker functions of reductive groups over local fields, where the functions studied by Whittaker are essentially the case where the local field is the real numbers and the group is SL2(R). Whittaker's equation is :\frac+\left(-\frac+\frac+\frac\right)w=0. It has a regular singular point at 0 and an irregular singular point at ∞. Two solutions are given by the Whittaker functions ''M''κ,μ(''z''), ''W''κ,μ(''z''), defined in terms of Kummer's confluent hypergeometric functions ''M'' and ''U'' by :M_\left(z\right) = \exp\left(-z/2\right)z^M\left(\mu-\kappa+\tfrac, 1+2\mu, z\right) :W_\left(z\right) = \exp\left(-z/2\right)z^U\left(\mu-\kappa+\tfrac, 1+2\mu, z\right). The Whittaker function W_(z) is the same as those with opposite va ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petersson Inner Product
In mathematics the Petersson inner product is an inner product defined on the space of entire modular forms. It was introduced by the German mathematician Hans Petersson. Definition Let \mathbb_k be the space of entire modular forms of weight k and \mathbb_k the space of cusp forms. The mapping \langle \cdot , \cdot \rangle : \mathbb_k \times \mathbb_k \rightarrow \mathbb, :\langle f , g \rangle := \int_\mathrm f(\tau) \overline (\operatorname\tau)^k d\nu (\tau) is called Petersson inner product, where :\mathrm = \left\ is a fundamental region of the modular group \Gamma and for \tau = x + iy :d\nu(\tau) = y^dxdy is the hyperbolic volume form. Properties The integral is absolutely convergent and the Petersson inner product is a positive definite Hermitian form. For the Hecke operators T_n, and for forms f,g of level \Gamma_0, we have: :\langle T_n f , g \rangle = \langle f , T_n g \rangle This can be used to show that the space of cusp forms of level \Gamma_ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prime Factorization
In number theory, integer factorization is the decomposition of a composite number into a product of smaller integers. If these factors are further restricted to prime numbers, the process is called prime factorization. When the numbers are sufficiently large, no efficient non-quantum integer factorization algorithm is known. However, it has not been proven that such an algorithm does not exist. The presumed difficulty of this problem is important for the algorithms used in cryptography such as RSA public-key encryption and the RSA digital signature. Many areas of mathematics and computer science have been brought to bear on the problem, including elliptic curves, algebraic number theory, and quantum computing. In 2019, Fabrice Boudot, Pierrick Gaudry, Aurore Guillevic, Nadia Heninger, Emmanuel Thomé and Paul Zimmermann factored a 240-digit (795-bit) number ( RSA-240) utilizing approximately 900 core-years of computing power. The researchers estimated that a 1024-bit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Square-free Integer
In mathematics, a square-free integer (or squarefree integer) is an integer which is divisible by no square number other than 1. That is, its prime factorization has exactly one factor for each prime that appears in it. For example, is square-free, but is not, because 18 is divisible by . The smallest positive square-free numbers are Square-free factorization Every positive integer n can be factored in a unique way as n=\prod_^k q_i^i, where the q_i different from one are square-free integers that are pairwise coprime. This is called the ''square-free factorization'' of . To construct the square-free factorization, let n=\prod_^h p_j^ be the prime factorization of n, where the p_j are distinct prime numbers. Then the factors of the square-free factorization are defined as q_i=\prod_p_j. An integer is square-free if and only if q_i=1 for all i > 1. An integer greater than one is the kth power of another integer if and only if k is a divisor of all i such that q_i\neq 1. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integer Ring
In mathematics, the ring of integers of an algebraic number field K is the ring of all algebraic integers contained in K. An algebraic integer is a root of a monic polynomial with integer coefficients: x^n+c_x^+\cdots+c_0. This ring is often denoted by O_K or \mathcal O_K. Since any integer belongs to K and is an integral element of K, the ring \mathbb is always a subring of O_K. The ring of integers \mathbb is the simplest possible ring of integers. Namely, \mathbb=O_ where \mathbb is the field of rational numbers. And indeed, in algebraic number theory the elements of \mathbb are often called the "rational integers" because of this. The next simplest example is the ring of Gaussian integers \mathbb /math>, consisting of complex numbers whose real and imaginary parts are integers. It is the ring of integers in the number field \mathbb(i) of Gaussian rationals, consisting of complex numbers whose real and imaginary parts are rational numbers. Like the rational integers, \mathb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gauss Sum
In algebraic number theory, a Gauss sum or Gaussian sum is a particular kind of finite sum of roots of unity, typically :G(\chi) := G(\chi, \psi)= \sum \chi(r)\cdot \psi(r) where the sum is over elements of some finite commutative ring , is a group homomorphism of the additive group into the unit circle, and is a group homomorphism of the unit group into the unit circle, extended to non-unit , where it takes the value 0. Gauss sums are the analogues for finite fields of the Gamma function. Such sums are ubiquitous in number theory. They occur, for example, in the functional equations of Dirichlet -functions, where for a Dirichlet character the equation relating and ) (where is the complex conjugate of ) involves a factor :\frac. History The case originally considered by Carl Friedrich Gauss was the quadratic Gauss sum, for the field of residues modulo a prime number , and the Legendre symbol. In this case Gauss proved that or for congruent to 1 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
