TASK DEFINITION: You will be given a passage, and your task is to generate a Yes/No question that is answerable based on the given passage.
PROBLEM: According to the theory of relativity, no information can travel faster than the speed of light in vacuum, but this does not mean that the refractive index cannot be lower than 1. The refractive index measures the phase velocity of light, which does not carry information. The phase velocity is the speed at which the crests of the wave move and can be faster than the speed of light in vacuum, and thereby give a refractive index below 1. This can occur close to resonance frequencies, for absorbing media, in plasmas, and for X-rays. In the X-ray regime the refractive indices are lower than but very close to 1 (exceptions close to some resonance frequencies). As an example, water has a refractive index of 6999999999740000000♠0.99999974 = 1 − 6993260000000000000♠2.6×10 for X-ray radiation at a photon energy of 6985480652946099999♠30 keV (0.04 nm wavelength).

SOLUTION: can a refractive index be less than 1?

PROBLEM: The Jack Russell Terrier is a small terrier that has its origins in fox hunting. It is principally white-bodied and smooth, rough or broken-coated but can be any colour.

SOLUTION: is a jack russell considered a small breed?

PROBLEM: The Great Pacific garbage patch, also described as the Pacific trash vortex, is a gyre of marine debris particles in the central North Pacific Ocean discovered between 1985 and 1988. It is located roughly between 135°W to 155°W and 35°N to 42°N. The collection of plastic, floating trash halfway between Hawaii and California extends over an indeterminate area of widely varying range depending on the degree of plastic concentration used to define the affected area.

SOLUTION:
is there a floating mass of garbage in the ocean?

