Short answer-half note.
In common time the quarter note equals one beat, and there are four quarter notes in a measure.
Songs in alla breve contain two beats per measure, with the half note equaling one beat. That means that the time signature of the alla breve is represented as 2/2 (not 4/4 as common time is).
He was inspired by the art of Pablo Picasso and Julio Gonzalez. During his early years before he became an artist he also worked in an automobile factory where he learning soldering and spot-welding techniques. He then started to mix his technical knowledge and art to create art.
