This would be a long list.
Some of the more well known names include:
Sigmund Freud
BF Skinner (Behavioral Psychology)
Jean Piaget (Developmental)
Ivan Pavlov (Classical Conditioning)
Isaac Newton Discovered the laws of gravity Albert Einstein General and Special theories of relativity Marie Curie Radiation Louise Pasteur Germ theory Gallileo Motion of planets round the sun Crick...
Andre AmpereAndre Marie Ampere was the first to explain the electro-dynamic theory. A permanent memorial to Ampere is the use of his name for the unit of electric current. George OhmGeorge Simon Ohm,...
There are literally thousands of famous scientists who have all made very important contributions to the field of science. All the winners of the Nobel Prize are, of course, extremely important...