This is true. Using a neutrino beam, the minimum latency would be approximately: (diameter of Earth) / (speed of light) ~= 42.5 milliseconds Some high-frequen

This is true. Using a neutrino beam, the minimum latency would be approximately: (diameter of Earth) / (speed of light) ~= 42.5 milliseconds Some high-frequency traders might actually be able to justify the investment needed to enable such low-latency communications! Come to think of it, you could also use gravitational waves...