FTP, name this quantum number, usually symbolized as m-sub-s.
In 1925, Samuel Goudsmit and George Uhlenbeck theorized its existence to explain some aspects of the periodic table, as well as fine structure.  It explains the results of the Stern-Gerlach experiment, in which an inhomogeneous magnetic field split a seemingly uniform beam of silver atoms into two beams.  Pauli suggested that it must have only two values, which are now defined as plus or minus one half.  FTP, name this quantum number, usually symbolized as m-sub-s.
In 1925, Samuel Goudsmit and George Uhlenbeck theorized its existence to explain some aspects of the periodic table, as well as fine structure.  
spin angular momentum