Each are the same intervals but because of the relative highness or lowness of the interval the difference will change. Each octave, or double, is divided into 1200 cents. Chance is an out growth of serialism, in an effort the remove the composer from the compositional process. Chance music is mostly associated wth John Cage and also evolved into the indeterminate sytle. It is a style of composition that takes advantage of all twelve tones.
Music is written with rows or sets of tones, and the variations of each.
It is another name for twelve- tone composition. The difference being that the double refers to twice the frequency of the first pitch and the octave means to go through the eight. Meaning that the octave consists of eight whole steps. Same as Homophonic. Were a melody is supported and played in conjunction with an underlying chord progression.