This is an account of Einstein's work and thoughts on the quantum theory. The following topics will be discussed: The light-quantum hypothesis and its gradual evolution into the photon concept. Barly history
o r t h e p h o t o e l e c t r i c e l e c t m e c h e o r ec a a n d e x p e r i m e n t a r e a s o n s
stronger and more protracted than for any other particle proposed to date.

Physics-based animations and interactions are becoming more common in UI. This page goes through some basic physical models and the kinds of interactions and animations that can be constructed from them.