Lexis then reasoned that if " Q " was sufficiently close to 1, then the time series was exhibiting what he called " normal dispersion " and one could assume that it was stable.
12.
In regions of normal dispersion, the " redder " portions of the pulse have a higher velocity than the " blue " portions, and thus the front of the pulse moves faster than the back, broadening the pulse in time.
13.
Over Karst's objections, by Christmas 1944 the United States is in possession of nearly 10, 000 " units " of radioactive dust, a " unit " being defined as the quantity which " would take care of a thousand men, at normal dispersion "; enough to kill the entire population of a large city such as Berlin.
14.
In a region of normal dispersion, high-frequency components have a faster group velocity than low-frequency ones, so the front of the precursor should have a period corresponding to that of the highest-frequency component of the original impulse; with increasing time, components with lower and lower frequencies arrive, so the period of the precursor becomes longer and longer until the lowest-frequency component arrives.
