<span>It is very interesting and controversial story, same as
personality and carrier of Sun Ra, themselves. Sun Ra was probably forced to
leave college because of financial problems and his growing sense of isolation,
but he claimed that he had a vision in which the aliens talked to him and told
him to leave college and to play music, because that is his mission. He
explained that, in this vision, he found him self on the planet that he
recognized as Saturn, and that aliens told him that the world is going into
complete chaos, and that he should speak through music and that the world will
hear. Sun Ra was an American jazz composer, bandleader, pianist and synthesizer
player, known for his experimental approach to the music and controversial personality.</span>
Hyperbolic plane geometry is also the geometry of saddle surfaces and pseudospherical surfaces, surfaces with a constant negative Gaussian curvature. A modern use of hyperbolic geometry is in the theory of special relativity, particularly Minkowski spacetime and gyrovector space.
Answer:
A valley fold is one where you fold the paper into itself. The paper should form a V when you unfold.
A mountain fold is where the paper is folded behind itself.