activity
20122025
most citedBias implies low rank for quartic polynomials

5 citations · 10 across the 11 of their papers we have counts for

collaborators

13 papers

math.NT2025

Polynomial Bounds for Birch's Theorem

Amichai Lampert, Andrew Snowden, Tamar Ziegler

Let be a number field and forms of odd degrees. In 1957, Birch proved that if is sufficiently large then the forms always have a nontr…

math.CO2025

Slice rank and partition rank of the determinant

Amichai Lampert, Guy Moshkovitz

The Laplace expansion expresses the determinant as a sum of products. Do shorter expansions exist? In this paper we: - Fully determine the slice rank deco…

math.NT2025

Density of solutions for systems of forms

Amichai Lampert

Let be a field of characteristic zero over which every diagonal form in sufficiently many variables admits a nontrivial solution. For example, may be a totally imaginary nu…

math.AG2025

Strength and partition rank under limits and field extensions

Arthur Bik, Jan Draisma, Amichai Lampert +1

The strength of a multivariate homogeneous polynomial is the minimal number of terms in an expression as a sum of products of lower-degree homogeneous polynomials. Partition rank i…

math.NT2024

Strength is bounded linearly by Birch rank

Benjamin Baily, Amichai Lampert

Let be a homogeneous polynomial over a field. For many fields, including number fields and function fields, we prove that the strength of is bounded above by a constant mul…

math.NT2024

Two improvements in Birch's theorem on forms

Amichai Lampert, Andrew Snowden

Let be a Birch field, that is, a field for which every diagonal form of odd degree in sufficiently many variables admits a non-zero solution; for example, could be the fiel…

math.CO2024

Slice rank and analytic rank for trilinear forms

Amichai Lampert

In this note, we present an elementary proof of the fact that the slice rank of a trilinear form over a finite field is bounded above by a linear expression in the analytic rank. T…

math.AC2023

Small ideals in polynomial rings and applications

Amichai Lampert

Let be a field which is either finite or algebraically closed and let We prove that any homogeneous of positive…

math.NT2022★ 2 cited

On rank in algebraic closure

Amichai Lampert, Tamar Ziegler

Let be a field and a form (homogeneous polynomial) of degree The -Schmidt rank of i…

math.AC2021★ 1 cited

Relative Rank and Regularization

Amichai Lampert, Tamar Ziegler

We introduce a new concept of rank - relative rank associated to a filtered collection of polynomials. When the filtration is trivial our relative rank coincides with Schmidt rank…

math.AG2021★ 2 cited

Schmidt rank and singularities

David Kazhdan, Amichai Lampert, Alexander Polishchuk

We revisit Schmidt's theorem connecting the Schmidt rank of a tensor with the codimension of a certain variety and adapt the proof to the case of arbitrary characteristic. We also…

math.CO2019★ 5 cited

Bias implies low rank for quartic polynomials

Amichai Lampert

We investigate the structure of polynomials of degree four in many variables over a fixed prime field . In 2007, Green and Tao proved that if a polynomia…

math.PR2012

On Maximizing the Speed of a Random Walk in Fixed Environments

Amichai Lampert, Assaf Shapira

We consider a random walk in a fixed Z environment composed of two point types: (q,1-q) and (p,1-p) for 1/2<q<p. We study the expected hitting time at N for a given number k of p-d…