Zijian Zeng

Dr. Zijian Zeng


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Academic Career Length

1Year (2026-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

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24 August 2026 in Preprints.org
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ZZZijian Zeng
Zijian Zeng
HLHoude Liu
Houde Liu
KRKuru Ratnavelu
Kuru Ratnavelu
SOSeng Huat Ong
Seng Huat Ong
We determine two finite models motivated by open problems in discrete geometry. Let $T_4=\{-1,0,1\}^4$. We prove that the maximum Borsuk number of a subset of $T_4$ is exactly 4: every nondegenerate subset can be partitioned into four sets of strictly smaller diameter, and a four-point equidistant set shows sharpness. Let $U_5=\{v/\lVert v\rVert:v\in\{-1,0,1\}^5\setminus\{0\}\}$. We also prove that a spherical code in $U_5$ with pairwise inner products at most $1/2$ has at most 40 points, with equality only for the $D_5$ root system inside this fixed library. The first result is certified by exact distance-layer colorings and an exhaustive symmetry-reduced enumeration of 15,056 maximal feasible sets; the second by two exact maximum-clique computations using integer predicates. These are finite-library theorems: they do not settle Borsuk's conjecture in $R^4$ or the unrestricted kissing numbers in dimensions 5 and 6.