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"path": "/abs/2604.03805v1",
"publishedAt": "2026-04-07T00:00:00.000Z",
"site": "https://arxiv.org",
"tags": [
"Mika Göös",
"Nathaniel Harms",
"Florian K. Richter",
"Anastasia Sofronova"
],
"textContent": "**Authors:** Mika Göös, Nathaniel Harms, Florian K. Richter, Anastasia Sofronova\n\nAlice and Bob are given $n$-bit integer pairs $(x,y)$ and $(a,b)$, respectively, and they must decide if $y=ax+b$. We prove that the randomised communication complexity of this Point--Line Incidence problem is $Θ(\\log n)$. This confirms a conjecture of Cheung, Hatami, Hosseini, and Shirley (CCC 2023) that the complexity is super-constant, and gives the first example of a communication problem with constant support-rank but super-constant randomised complexity.",
"title": "No Constant-Cost Protocol for Point--Line Incidence"
}