Italy in Cosmic Rays and X-ray astronomy) and a number of Italian physicists were forced to leave Italy in the 1930s by Fascist laws against Jews. Other prominent physicists include: Amedeo Avogadro (most noted for his contributions to molecular theory, in particular the Avogadro's law and the Avogadro constant), Evangelista Torricelli (inventor of barometer), Alessandro Volta (inventor of electric battery), Guglielmo Marconi (inventor of radio), Galileo Ferraris and Antonio Pacinotti, pioneers of the induction motor, Alessandro Cruto, pioneer of light bulb and Innocenzo Manzetti, eclectic pioneer of auto and robotics, Ettore Majorana (who discovered the Majorana fermions), Carlo Rubbia (1984 Nobel
Volta potential by its work function, and so dissimilar metals can show an electric potential difference even at equilibrium. The Volta potential is "not" an intrinsic property of the two bulk metals under consideration, but rather is determined by work function differences between the metals' surfaces. Just like the work function, the Volta potential depends sensitively on surface state, contamination, and so on. The potential is given by the formula: formula_1, where V is the potential, The Volta potential can be significant (of order 1 volt) but it cannot be measured directly by an ordinary voltmeter. A voltmeter does not measure vacuum