Galois self-orthogonal MDS codes with large dimensions
Ruhao Wan, Shixin Zhu
TL;DR
This work advances the theory of Galois self-orthogonal MDS codes in the $q$-ary setting by developing a general framework that tests $e$-Galois self-orthogonality via the map $\Phi_{\bm{v}}({\mathcal C})$ and its extension. It delivers necessary and sufficient conditions for (extended) GRS and EGRS codes to be $e$-Galois self-orthogonal, and partitions the parameter space into three cases based on $\frac{m}{s}$ and parity, enabling the construction of new MDS codes with dimensions exceeding the conventional bound $\big\lfloor\frac{n+p^e-1}{p^e+1}\big\rfloor$. The paper provides explicit constructions for lengths $1\le n\le p^s+1$, $p^s+1\le n\le p^{2s}+1$, and $n=q+1$, and demonstrates that propagation rules yield MDS codes with Galois hulls of arbitrary dimension, with significant implications for quantum codes via EAQECCs. Overall, the results enrich the catalog of high-dimension Galois self-orthogonal MDS codes and offer practical avenues for quantum-information applications.
Abstract
Let $q=p^m$ be a prime power, $e$ be an integer with $0\leq e\leq m-1$ and $s=\gcd(e,m)$. In this paper, for a vector $v$ and a $q$-ary linear code $C$, we give some necessary and sufficient conditions for the equivalent code $vC$ of $C$ and the extended code of $vC$ to be $e$-Galois self-orthogonal. From this, we directly obtain some necessary and sufficient conditions for (extended) generalized Reed-Solomon (GRS and EGRS) codes to be $e$-Galois self-orthogonal. Furthermore, for all possible $e$ satisfying $0\leq e\leq m-1$, we classify them into three cases (1) $\frac{m}{s}$ odd and $p$ even; (2) $\frac{m}{s}$ odd and $p$ odd; (3) $\frac{m}{s}$ even, and construct several new classes of $e$-Galois self-orthogonal maximum distance separable (MDS) codes. It is worth noting that our $e$-Galois self-orthogonal MDS codes can have dimensions greater than $\lfloor \frac{n+p^e-1}{p^e+1}\rfloor$, which are not covered by previously known ones. Moreover, by propagation rules, we obtain some new MDS codes with Galois hulls of arbitrary dimensions. As an application, many quantum codes can be obtained from these MDS codes with Galois hulls.
