Is soft hair, ranging in length between one and one and a half centimeters, considered evidence of puberty, or is coarse hair a prerequisite for that? And what is the specific description of pubic hair that is considered evidence of puberty according to scholars?

The authoritative criterion for pubic hair that indicates puberty is coarse hair that warrants removal with a razor, not the fine, downy hair that may appear in children. What was mentioned about hair length without coarseness is unlikely, and if it does occur, coarseness is the considered factor.