Thresholds for colouring the random Borsuk graph

This paper establishes that the chromatic number of the random Borsuk graph transitions from being kk-colourable to requiring more than kk colours when the average degree is constant for $2 \leq k \leq d,andfurtheridentifiessharpthresholdsforthesetransitions,particularlycharacterizingthe, and further identifies sharp thresholds for these transitions, particularly characterizing the k=2$ case via continuum AB percolation.

Álvaro Acitores Montero, Matthias Irlbeck, Tobias Müller + 1 more2026-03-06🔢 math

Counting Fq\mathbb F_q-points of orbital varieties in ad-nilpotent ideals of type AnA_n

This paper establishes two explicit formulas for counting Fq\mathbb F_q-points of orbital varieties in ad-nilpotent ideals of type AnA_n using Hall-Littlewood functions and qq-weighted tableaux, while providing new proofs and applications for results concerning nilpotent Hessenberg varieties, square-zero matrices, and double coset counts.

Mohammad Bardestani, Keivan Mallahi-Karai, Samrith Ram + 1 more2026-03-05🔢 math

Measures on Cameron's treelike classes and applications to tensor categories

This paper completes the classification of measures on Cameron's elementary treelike Fraïssé classes by establishing a bijection for nn-colored rooted binary trees that yields infinite families of novel semisimple tensor categories with superexponential growth, while simultaneously proving the nonexistence of such measures on nn-colored and labeled tree classes for n2n \geq 2.

Thanh Can, Thomas Rüd2026-03-05🔢 math

When Relaxation Does Not Help: RLDCs with Small Soundness Yield LDCs

This paper demonstrates that any non-adaptive qq-query relaxed locally decodable code (RLDC) with sufficiently small soundness error can be converted into a standard qq-query locally decodable code (LDC) with comparable parameters, thereby generalizing previous separation results and yielding improved lower bounds for RLDCs, relaxed locally correctable codes (RLCCs), and probabilistically checkable proofs of proximity (PCPPs).

Kuan Cheng, Xin Li, Songtao Mao2026-03-05🔢 math