It is known that the reciprocal gamma function $1/\Gamma$ is entire of order 1 meaning, in particular, that for any $\varepsilon > 1$ there exists $C_\varepsilon > 0$ such that $$ \left| \frac{1}{\Gamma(c+it)} \right| \leq C_\varepsilon e^{|t|^\varepsilon} \quad t \in \mathbb R. $$ Now consider the function $$ \Gamma_f(c_1+i x_1,c_2 + ix_2) = \int\limits_0^\infty \int\limits_0^\infty y_1^{ix_1+c_1-1} y_2^{ix_2 + c_2 -1} e^{-f(y_1,y_2)} \, dy_1 dy_2, $$ where $f(y_1,y_2)$ is a smooth positive and positively homogeneous of order 1, i.e. $f(\lambda y_1, \lambda y_2) = \lambda f(y_1,y_2)$, $\lambda > 0$; $c_1$, $c_2 > 0$. If $f(y_1,y_2)=y_1+y_2$ then $$ \Gamma_f(c_1+ix_1,c_2+ix_2) = \Gamma(c_1+ix_1)\Gamma(c_2+ix_2) $$ so that for any $\varepsilon > 1$ there exists $C_\varepsilon > 0$ such that $$ |\Gamma_f(c_1 + ix_1, c_2 + ix_2)|^{-1} \leq C_\varepsilon e^{|x|^\varepsilon}, \quad x \in \mathbb R^2. $$ My question is whether this inequality also holds in the case of arbitrary smooth positive and positively homogeneous $f$? If the answer is non-trivial, what techniques should I use to obtain some similar estimate? For gamma function this is obtained using integration by parts which doesn't lead to something good in the case of general $f$.
2026-04-01 01:02:36.1775005356
Decay of reciprocal gamma function and similar functions
148 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in IMPROPER-INTEGRALS
- multiplying the integrands in an inequality of integrals with same limits
- Closed form of integration
- prove that $\int_{-\infty}^{\infty} \frac{x^4}{1+x^8} dx= \frac{\pi}{\sqrt 2} \sin \frac{\pi}{8}$
- Generalized Fresnel Integration: $\int_{0}^ {\infty } \sin(x^n) dx $ and $\int_{0}^ {\infty } \cos(x^n) dx $
- Need a guide how to solve Trapezoidal rule with integrals
- For which values $p$ does $\int_0^\infty x\sin(x^p) dx $ converge?
- Proving $\int_0^1\frac{dx}{[ax+b(1-x)]^2}=\frac1{ab}$
- Contour integration with absolute value
- Use the comparison test to determine whether the integral is convergent or divergent.
- Can I simply integrate this function?
Related Questions in GAMMA-FUNCTION
- contour integral involving the Gamma function
- Generalized Fresnel Integration: $\int_{0}^ {\infty } \sin(x^n) dx $ and $\int_{0}^ {\infty } \cos(x^n) dx $
- Proving that $\int_{0}^{+\infty}e^{ix^n}\text{d}x=\Gamma\left(1+\frac{1}{n}\right)e^{i\pi/2n}$
- How get a good approximation of integrals involving the gamma function, exponentials and the fractional part?
- How to prove $\int_{0}^{\infty} \sqrt{x} J_{0}(x)dx = \sqrt{2} \frac{\Gamma(3/4)}{\Gamma(1/4)}$
- How do we know the Gamma function Γ(n) is ((n-1)!)?
- How to calculate this exponential integral?
- How bad is the trapezoid rule in the approximation of $ n! = \int_0^\infty x^n \, e^{-x} \, dx $?
- Deriving $\sin(\pi s)=\pi s\prod_{n=1}^\infty (1-\frac{s^2}{n^2})$ without Hadamard Factorization
- Find the value of $A+B+C$ in the following question?
Related Questions in ESTIMATION
- Question on designing a state observer for discrete time system
- Some help with calculating the time remaining please???
- Is the usage of unbiased estimator appropriate?
- How to statistically estimate multiple linear coefficients?
- Is there an intuitive way to see that $\mathbb{E}[X|Y]$ is the least squares estimator of $X$ given $Y$?
- minimizing MSE of estimator $\theta(a,b) = \frac{1}{n} \sum^n_{i=1} Y_ia_i + b$
- a limit about exponential function
- I don't understand where does the $\frac{k-1}{k}$ factor come from, in the probability mass function derived by Bayesian approach.
- hints for calculation of double integral
- estimation of $\mu$ in a Gaussian with set confidence interval
Trending Questions
- Induction on the number of equations
- How to convince a math teacher of this simple and obvious fact?
- Find $E[XY|Y+Z=1 ]$
- Refuting the Anti-Cantor Cranks
- What are imaginary numbers?
- Determine the adjoint of $\tilde Q(x)$ for $\tilde Q(x)u:=(Qu)(x)$ where $Q:U→L^2(Ω,ℝ^d$ is a Hilbert-Schmidt operator and $U$ is a Hilbert space
- Why does this innovative method of subtraction from a third grader always work?
- How do we know that the number $1$ is not equal to the number $-1$?
- What are the Implications of having VΩ as a model for a theory?
- Defining a Galois Field based on primitive element versus polynomial?
- Can't find the relationship between two columns of numbers. Please Help
- Is computer science a branch of mathematics?
- Is there a bijection of $\mathbb{R}^n$ with itself such that the forward map is connected but the inverse is not?
- Identification of a quadrilateral as a trapezoid, rectangle, or square
- Generator of inertia group in function field extension
Popular # Hahtags
second-order-logic
numerical-methods
puzzle
logic
probability
number-theory
winding-number
real-analysis
integration
calculus
complex-analysis
sequences-and-series
proof-writing
set-theory
functions
homotopy-theory
elementary-number-theory
ordinary-differential-equations
circles
derivatives
game-theory
definite-integrals
elementary-set-theory
limits
multivariable-calculus
geometry
algebraic-number-theory
proof-verification
partial-derivative
algebra-precalculus
Popular Questions
- What is the integral of 1/x?
- How many squares actually ARE in this picture? Is this a trick question with no right answer?
- Is a matrix multiplied with its transpose something special?
- What is the difference between independent and mutually exclusive events?
- Visually stunning math concepts which are easy to explain
- taylor series of $\ln(1+x)$?
- How to tell if a set of vectors spans a space?
- Calculus question taking derivative to find horizontal tangent line
- How to determine if a function is one-to-one?
- Determine if vectors are linearly independent
- What does it mean to have a determinant equal to zero?
- Is this Batman equation for real?
- How to find perpendicular vector to another vector?
- How to find mean and median from histogram
- How many sides does a circle have?