11.54 Winding Number
The number of circuits made by a loop around a point is its ' winding number '. This idea has powerful applications to the classification of functions.
11.15 Modulation and Noise
Radio signals are nearly always transmitted by a coded variation of a continuous ' carrier ' beam. Each modulation system has a different noise.
12.40 Profit and Patronage in Urban Development
How can history help us understand modern development? Sir John Summerson looks at the 18th-century development of Bloomsbury to see what lessons we can learn today.