English

Expanding phenomena over matrix rings

Number Theory 2019-03-26 v3 Combinatorics

Abstract

In this paper, we study expanding phenomena in the setting of matrix rings. More precisely, we will prove that If AA is a set of M2(Fq)M_2(\mathbb{F}_q) and Aq7/2|A|\gg q^{7/2}, then we have A(A+A), A+AAq4.|A(A+A)|, ~|A+AA|\gg q^4. If AA is a set of SL2(Fq)SL_2(\mathbb{F}_q) and Aq5/2|A|\gg q^{5/2}, then we have A(A+A), A+AAq4.|A(A+A)|, ~|A+AA|\gg q^4. We also obtain similar results for the cases of A(B+C)A(B+C) and A+BCA+BC, where A,B,CA, B, C are sets in M2(Fq)M_2(\mathbb{F}_q).

Keywords

Cite

@article{arxiv.1803.08357,
  title  = {Expanding phenomena over matrix rings},
  author = {Yeşim Demiroğlu Karabulut and Doowon Koh and Thang Pham and Chun-Yen Shen and Le Anh Vinh},
  journal= {arXiv preprint arXiv:1803.08357},
  year   = {2019}
}

Comments

31 pages

R2 v1 2026-06-23T01:01:50.074Z