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2 votes
0 answers
138 views

On the solutions of $_2F_1(\alpha, \beta; \gamma, z) = \Lambda$

More General Question Let $$F(\alpha,\beta;\gamma;z) = \sum_{n=0}^{+\infty} \frac{(\alpha)_n(\beta)_n}{(\gamma)_nn!}z^n, \quad |z| < 1, \quad (x)_n = x(x+1)...(x+n-1), \quad (x)_0 = 1$$ be the ...
Desura's user avatar
  • 233
2 votes
1 answer
112 views

References for group of invariance of the Painlevé property

I'm searching for some references about groups of invariance of the Painlevé property other than the book of Robert Conte or more generally birational transformation of Riemann surfaces.
Redouane Khaled's user avatar
2 votes
0 answers
90 views

Second order estimates for Dirichlet problem for complex Monge-Ampere equation

Let $\Omega\subset \mathbb{C}^n$ be a bounded pseudo-convex domain. Let $0<f\in C^{\infty}(\bar\Omega)$, $\phi\in C^\infty(\partial \Omega)$. Consider the Dirichlet problem for the complex Monge -...
asv's user avatar
  • 21.8k
2 votes
0 answers
180 views

Multiple zeta values related to fractional calculus and an Appell polynomial sequence

There is an Appell sequence of polynomials $p_n(z)$ related to an infinitesimal generator for one rep of the fractional calculus that have coefficients involving the Riemann zeta function values at ...
Tom Copeland's user avatar
  • 10.5k
2 votes
0 answers
154 views

Algebra of meromorphic functions on a Riemann surface

Let $C$ be compact Riemann surface of high genus. Let $p$ be a general point on $C$ and $z$ a local coordinate around $p$. Given a meromorphic function on $C$, regular outside $p$, we can look at its ...
Giulio's user avatar
  • 2,384
2 votes
0 answers
61 views

Criteria for a limit to be a proper function

This question is obviously broad; turning this broadness into something sharp is part of the problem. Given a sequence of functions defined on a Riemann Surface $R$, valued in $\Bbb C^2$, what ...
Joe's user avatar
  • 779
2 votes
0 answers
117 views

automorphic form associated with Apollonian Gasket

In /Indra's Pearls/, it's mentioned one can associate automorphic forms with limit sets. Is there an explicit description of the one associated with the Apollonian gasket (up to some appropriate ...
graveolensa's user avatar
2 votes
0 answers
219 views

Integral with product of two infinite sums

I am looking for references and results on integrals with product of two infinite sums: $$S_1=\int_0^{\infty} \sum_{n=0}^{\infty} f(nx) \sum_{k=0}^{\infty} \overline{ g(kx)} dx$$ Above integral is ...
Bertrand's user avatar
  • 1,199
2 votes
0 answers
320 views

Solution to algebraic equations over $\mathbb{C}$ and $\mathbb{C}[x]$

$t^n=a$, we get one solution to the equation: $$t=e^{\frac{1}{n}\int^a_1 \frac{1}{x}}$$ generalizing this result by replacing the exponential with an elliptic modular function and the integral with ...
XL _At_Here_There's user avatar
2 votes
0 answers
59 views

explicit conformal map of sinus-shaped region

I wonder weather an explicit conformal map of a sinus-shaped region given by $\Re(z) \in [0, 1+\delta \sin(\Im(z)) ]$ onto say a strip or a ball is known (of course $0<\delta < 1$). Thank you.
Eric's user avatar
  • 53
2 votes
0 answers
173 views

Does this symmetrization operator have a name? Any theory?

Consider a function $f(x_1,\ldots,x_n)$ of $n$ complex variables. Define $$f_{\mathrm{symm}}(x_1,\ldots,x_n) = 2^{-n}\sum_{\varepsilon_1,\ldots,\varepsilon_n=\pm 1} f(\varepsilon_1x_1,\ldots,\...
Brendan McKay's user avatar
2 votes
0 answers
179 views

Questions about transformation or integral transformation

I have asked several mathematicians about the following questions,but all of them think they are good questions,but can not give a complete answer.Now I have to come here to ask mathematicians all ...
XL _At_Here_There's user avatar
2 votes
0 answers
215 views

ALE Kähler manifolds are birational to deformations of $\mathbb{C}^n/G$.

I am reading Dominic Joyce's book 'Compact Manifolds with Special Holonomy' and I am struggling to understand a remark he makes at the end of chapter 8. The assertion is (I think) the following: ...
oydeis's user avatar
  • 21
1 vote
1 answer
655 views

Series involving factorials

Playing around with this series for natural values of $a,b$, it appears that more generally for $c\in\mathbb N$, $$\sum_{k=0}^\infty \frac{ (a+k)! \ (b+k)!}{k!\ (a+b+c+ k+1)! }=\frac{a!\ b!\ (c-1)!}{...
Wolfgang's user avatar
  • 13.4k
1 vote
1 answer
218 views

Generating series of rational$\times \exp($rational$)$

It is known that rational functions $f\in \mathbb C(x)$, $0$ not a pole, are the sum of generating series $\sum_{n\geq 0} a_nx^n$ where $(a_n)_n$ is solution of a linear recurrence with constant ...
Loïc Teyssier's user avatar
1 vote
1 answer
130 views

distance-set along the orbit of $e^{2\pi i\theta}$

Let $z=e^{2\pi i\theta}$ for a fixed real number $\theta$. It's known that if $\theta\not\in\mathbb{Q}$ (is irrational) then the set $S(\theta)=\{z^n: n\in\mathbb{N}\}$ is dense on the unit circle $\...
T. Amdeberhan's user avatar
1 vote
1 answer
393 views

The Dirichlet series of the Hasse–Weil L-function

I have the following question: Is there is a paper claiming that the Dirichlet series of the Hasse–Weil $L$-function (associated with an elliptic curve over rationals) is of finite order. Thank you in ...
Safwane's user avatar
  • 1,197
1 vote
1 answer
179 views

One trig "survives" a binomial summation: why?

I've seen many trigonometric identities but here is one that I encountered for which I did not find a reference. In case you wonder where this came from, I was investigating certain $q$-series in ...
T. Amdeberhan's user avatar
1 vote
1 answer
241 views

Subharmonic function in unbounded regions

The harmonic majorization for a subharmonic function $h$ is well-known for bounded regions $\Omega \subset \mathbb{C}$: $$h \le 0 \text{ in }\partial \Omega \Longrightarrow h \le 0 \text{ in }\Omega.$$...
S. Euler's user avatar
  • 285
1 vote
2 answers
354 views

Reference request and clarification for Central Limit Theorem for complex random variables

I'm looking for a reference and a proof of the following version (or eventually a more general version) of the Central Limit Theorem for complex random variables. Theorem. Let $Z_1, Z_2, \dots, Z_n$ ...
rosan98's user avatar
  • 361
1 vote
1 answer
344 views

Is there a way to tie up even and "newly suggested odd" Riemann zeta values?

Define the sequence $$a_s=(-1)^{\binom{s-1}2}\left(\frac{\pi}2\right)^s\frac1{2\cdot s!}\begin{cases} s\,E_{s-1}, \qquad \text{if $s$ is odd} \\ 2^{2s}B_s, \qquad \,\,\text{if $s$ is even};\end{cases}$...
T. Amdeberhan's user avatar
1 vote
2 answers
698 views

Extension of harmonic function at infinity

Can a harmonic function defined on the upper half-plain (or any domain which is unbounded) be extended to the point at infinity. If so, under what condition. What happens to the mean value property ...
Vagabond's user avatar
  • 1,795
1 vote
1 answer
65 views

Reference dual Dirichlet space $D^1$

Let $\mathbb{D} = \{ z \in \mathbb{C} : |z| < 1 \}$ be the unit disk. The Bergman space $A^1 = A^1(\mathbb{D})$ is the Banach space of holomorphic functions on $\mathbb{D}$ such that $$ \|f\|_{A^1} ...
Scottish Questions's user avatar
1 vote
1 answer
151 views

SOT and WOT convergence of Toeplitz operators

For the Hardy space $H^2$, every $\phi \in L^\infty (\mathbb T)$ induces a bounded Toeplitz operator $T_\phi$ on the Hardy space and $\lVert T_\phi \rVert = \lVert \phi \rVert _{\infty}$. Consequently,...
ash's user avatar
  • 151
1 vote
1 answer
61 views

Reference request for value distribution theory of bicomplex meromorphic functions

While there is abundant literature available on value distribution of meromorphic functions, I am interested to know whether the value distribution theory for bicomplex meromorphic functions has been ...
Nik's user avatar
  • 165
1 vote
1 answer
518 views

Zeros of Multivariate Complex Functions [need reference]

I am looking for a good accessible reference that would summarize properties of zeros of complex analytic functions. For my purpose, it would be interesting to see a discussion on the following ...
Boby's user avatar
  • 671
1 vote
1 answer
166 views

Is the $n$'th super root analytic in a half plane?

This question has been bogging me down lately. I'm not sure how to come up with an approach to tackle the proof exactly. I'm without a proof, butI think the result I'm searching for is true. Similarly,...
user avatar
1 vote
1 answer
252 views

Hilbert scheme of an infinitesimal neighborhood of a subvariety

Let $X$ be a complex algebraic variety. Let $C\subset X$ be a compact (reduced) subvariety. Let $C^{(n)}$ denote the $n$th infinitesimal neighborhood of $C$ inside $X$. Let $Hilb(X)$ denote the ...
asv's user avatar
  • 21.8k
1 vote
1 answer
2k views

The zeros of the digamma function

I wonder what work have been done on the zeros of the digamma function and on the values of the gamma function at such points (on the negative real axis). Any help please :)
Tri Ngo's user avatar
  • 19
1 vote
1 answer
119 views

Estimating two dimensional theta function

My feeling is that this should be written somewhere but I don't know what to search for. Let $Q(x,y)$ be a binary quadratic form over $\mathbb{C}$, with $\operatorname{Re}(Q)$ positive definite. Then ...
user49822's user avatar
  • 2,178
1 vote
1 answer
486 views

Mandelbrot set and logistic map connection

I'm currently writing an undergraduate thesis on chaos theory with a particular focus on the connection between the Mandelbrot set and the logistic map. I have found scattered posts on this site, ...
Person21312412's user avatar
1 vote
1 answer
177 views

Conformal mapping of multiply connected domains

I am studying conformal mappings of multiply connected domains. Most of the results that I can reach concern existence and uniqueness of such mappings, whereas I can not find anything satisfactory ...
hassan's user avatar
  • 11
1 vote
1 answer
380 views

Infinite compositions of holomorphic functions, is there literature on the subject?

I've recently become very intrigued by infinite compositions. To get at what I mean by the term, I'll be as explanatory as possible. Consider a sequence of holomorphic functions $\{\phi_j\}_{j=0}^\...
user avatar
1 vote
1 answer
1k views

A generalization of the Grauert direct image theorem

EDIT: Let $f\colon X\to Y$ be proper holomorphic submersive map of complex analytic manifolds. Let $\mathcal{F}$ be the sheaf of holomorphic sections of a holomorphic vector bundle over $X$. Assume ...
asv's user avatar
  • 21.8k
1 vote
1 answer
143 views

On the geometry of roots of a sum of complex linear fractions

I was wondering if there is anything known about the geometry (position) of the roots of a rational map of the form $$R(z):= \sum_{j=1}^{n} \frac{a_j}{z-p_j},$$ where the $a_j$'s are nonzero complex ...
Malik Younsi's user avatar
  • 2,154
1 vote
1 answer
554 views

Conformal mapping of C \ D* onto C \ (-1, 1) [closed]

Which is the concrete formula for the conformal mapping (normalized at infinity), acting from $\mathbb C \backslash D^*$ onto $\mathbb C\backslash[-1, 1]$? Here $\mathbb C$ denotes the set of all ...
george's user avatar
  • 21
1 vote
0 answers
52 views

Description of all biholomorphic maps from annulus [duplicate]

Consider the collection $\mathcal{C}$ of all maps $f \colon B_1 -\overline{B}_\beta \to \mathbb{C}$ such that $f$ is biholomorphic onto its image. Is this collection $\mathcal{C}$ path-connected? In ...
Jinyang wu's user avatar
1 vote
0 answers
127 views

an eigenvalue problem for Jacobi Forms

Assume $G(q,z)$ is a Jacobi form of a certain index k. It is known that $G$ can be expanded in a Taylor series with coefficients in the ring of quasi-modular forms (generators $E_2, E_4$ and $E_6$). $\...
T. Amdeberhan's user avatar
1 vote
0 answers
111 views

Residues of analytic operators

Suppose we have analytic operators $P_{z}: C^1[0,1]\to C^1[0,1]$, where $z \in \mathbb{C}$, and the spectrum of $P_{z_0}$ possesses an isolated eigenvalue $1$ (assuming multiplicity is 1 and $I-P_z$ ...
opera's user avatar
  • 11
1 vote
0 answers
210 views

Proving that quotient of orthogonal polynomials is a Padé approximant of Stieltjes transform

This question is reposted from Math Stack Exchange (you can see the original post here). The motivation for reposting is that I feel like the question isn't getting much attention in MSE - if there is ...
Rodrigo's user avatar
  • 51
1 vote
0 answers
116 views

Converse of transfer theorem : does asymptotic behaviour of coefficients describe the singularity?

I'm interested in Singularity Analysis after reading this Math.Stack post. In the "Analytic Combinatorics" book by P. Flajolet and R. Sedgewick, at p.390, the following transfer theorem (...
Desura's user avatar
  • 233
1 vote
0 answers
144 views

Zeroes of Mellin transform

There exist a "standard" or canonical way to construct a real valued function whose Mellin transform has a prescribed set of zeroes? Clearly for some set of zeroes this could be impossible ...
MathG's user avatar
  • 131
1 vote
0 answers
79 views

Resources/books/articles about estimation of $|f(z)|$ [closed]

I am new to complex analysis and I want to explore the following problem: for a complex valued bounded function $f(z)$ in a domain, I would like to know how we estimate the modulus values in a given ...
AgnostMystic's user avatar
1 vote
0 answers
199 views

What is decoupling theory means on Tao Blog ? And what is its purpose in mathematics? [closed]

I accrossed on Tao Blog a new theory for me which it is called "Decoupling theory", But I didn't find in the web its definition and its purpose , I find only this article in wiki but this very far ...
user avatar
1 vote
0 answers
49 views

Permutation of eigenvalues induced by a loop

A friend of mine just mention me what I think is a very fun phenomena and I would be very interested to learn more about it: Let $A,B\in \mathbb{C}^{n\times n}$ two matrices. And let $\lambda_1(z), \...
RaphaelB4's user avatar
  • 4,361
1 vote
0 answers
294 views

Can an entire function have every root function?

My question is an amalgamation of two previous questions. The first question I'd like to draw attention to is here. It asks whether there can exist a non trivial semigroup defined on $\mathbb{C}$ $$\...
user avatar
1 vote
0 answers
52 views

Composing between Schröder functions in complex dynamics

Assume that $f(z)$ is a holomorphic function that sends some open and connected set $G$ to itself. Assume $f$ has a single fixed point $z_0$. Assume $f(f(...(n\,times)...f(z))) = f^{\circ n}(z) \to ...
user avatar
1 vote
1 answer
133 views

Iterated sums--something like a differsum

So I've been fiddling around with the cauchy product of sequences lately, and am curious about a little identity I've found (which I'm sure is ubiquitous in finite differences, as I can't be the only ...
user avatar
1 vote
0 answers
201 views

Applications of Iss'sa's theorem on homomorphisms between algebras of meromorphc functions

In Remmert's book Funktionentheorie II, the following theorem, apparently due to Hironaka under the pseudonym Iss'sa, is proved: Let $U,V \subseteq \mathbb{C}$ be open subsets. Every $\mathbb{...
user91363's user avatar
1 vote
0 answers
217 views

Homeomorphism of fibers of holomorphic maps

EDIT (after the comment by Jason Starr): Let $X$ be a complex algebraic (or, more generally, analytic) variety, possibly singular and non-compact. Let $f\colon X\to D^*$ be a proper algebraic morphism ...
asv's user avatar
  • 21.8k