Improved Lower Bounds for Shoreline Search.

Shoreline search is a natural and well-studied generalisation of the classical cow-path problem: k initially co-located unit speed agents are searching for a line (called shoreline) in 2 dimensional Euclidean space. The shoreline is at (a possibly unknown) distance \\(\\delta \\) from the starting point \\(O\\) of the agents. The goal is to minimize the competitive ratio \\(\\frac{T_{\\delta }}{\\delta }\\), where \\(T_{\\delta }\\) is the worst case (over all possible locations of the shoreline at distance \\(\\delta \\)) time until the shoreline is found.