摘要
The conjecture that ultra-high-energy cosmic rays (UHECRS) are actually strangelets is discussed. Besides the reason that strangelets can do as cosmic rays beyond the Greisen-Zatsepin-Kuzmin-cutoff, another argument to bombarding bare strange stars. It is proposed that the exotic quark surface of a bare strange star could be an effective astro-laboratory in the investigations of the extra dimensions and of the detection of ultra-high-energy neutrino fluxes. The flux of neutrinos (and other point-like particles) with energy larger than 2.3×10^20 eV could be expected to be smaller than 10^-26 cm^-2 s^-1 if there are two extra spatial dimensions.
