Related Experiment Video
Updated: Mar 24, 2026

Shaping the Amplitude and Phase of Laser Beams by Using a Phase-only Spatial Light Modulator
Published on: January 28, 2019
The shifted convolution problem in function fields
Alexandra Florea1, Matilde Lalín2, Amita Malik3
1Department of Mathematics, University of California Irvine, 340 Rowland Hall, Irvine, CA 92697 USA.
This study analyzes the shifted convolution of divisor functions in function fields, establishing an asymptotic formula for large degrees. It also explores correlations of Dirichlet characters and introduces a novel Voronoi summation formula for function fields.
Area of Science:
- Number Theory
- Algebraic Geometry
- Analytic Number Theory
Background:
- The study of divisor functions and their correlations is a central theme in analytic number theory.
- Function fields provide a rich testing ground for number-theoretic conjectures, analogous to integers.
- Previous work has focused on the integer case, with limited results for function fields.
Purpose of the Study:
- To investigate the shifted convolution problem for the divisor function in function fields.
- To derive an asymptotic formula for the average value of d(f)d(f+h) in the large degree limit.
- To analyze mixed and self-correlations of Dirichlet characters and related functions in function fields.
Main Methods:
- Utilizing the large degree limit for polynomials over finite fields (F_q[T]).
- Developing and applying a Voronoi summation formula specific to function fields.
- Employing techniques from analytic number theory and algebraic geometry.
Main Results:
- An asymptotic formula is proven for the shifted convolution of divisor functions, valid for deg(h) < (2-epsilon)deg(f).
- Asymptotic formulae are established for mixed and self-correlations involving Dirichlet characters and their convolutions.
- The study yields results on correlations of norm-counting functions for quadratic extensions.
Conclusions:
- The research extends classical number theory problems to the function field setting.
- The newly developed Voronoi summation formula is a significant contribution, enabling further research.
- The findings provide new insights into the distribution and correlations of arithmetic functions in function fields.
Related Concept Videos
Convolution: Math, Graphics, and Discrete Signals
To simplify the convolution integral, it is assumed that both the input signal and impulse response are zero for negative time values. The graphical convolution process...
Convolution Properties I
The commutative property reveals that the input and the impulse response of an LTI (Linear Time-Invariant) system can be interchanged without affecting the output:
Convolution Properties II
The width property indicates that if the durations of input signals are T1 and T2, then the width of the output response equals the sum of both durations, irrespective of the shapes of the two functions. For instance, convolving two rectangular pulses with durations of 2 seconds and 1 second results in a function with a width of 3 seconds.
The area property asserts that the area under the...
Properties of Fourier Transform II
The Frequency Shifting property of Fourier Transforms highlights that a shift in the frequency domain corresponds to a phase shift in the time domain. Mathematically, if x(t) has...
Properties of DTFT II
The frequency differentiation property is illustrated by considering a DTFT pair and differentiating both sides with respect to ω.
Transformations of Functions II

