London Underground has said “excess sunlight” is causing delays for the Tube network.

Bright sunshine beaming onto CCTV monitors, which are used to give a clear view of the platform before pulling away, is blocking drivers’ line of sight, according to staff.

With an advance that one cryptography expert called a “masterpiece,” University of Texas at Austin computer scientists have developed a new method for producing truly random numbers, a breakthrough that could be used to encrypt data, make electronic voting more secure, conduct statistically significant polls and more accurately simulate complex systems such as Earth’s climate.

The new method creates truly random numbers with less computational effort than other methods, which could facilitate significantly higher levels of security for everything from consumer credit card transactions to military communications.

The new method takes two weakly random sequences of numbers and turns them into one sequence of truly random numbers. Weakly random sequences, such as air temperatures and stock market prices sampled over time, harbor predictable patterns. Truly random sequences have nothing predictable about them, like a coin toss.