Changes

Einstein's statistical explanation of Brownian motion (the random movement of microscopic particles mixed in with pollen) is sometimes credited with helping to confirm the atomic theory at a time when some scientists argued against it.<ref>Cassidy, David (2004). [http://www.aip.org/history/einstein/essay-brownian.htm "Einstein on Brownian motion"].  [http://www.aip.org/history/einstein/great1.htm American Institute of Physics/AIP Center for History of Physics/Albert Einstein-Image and Impact/The Great Works I].  Retrieved on January 24, 2014.</ref> Most scientists had accepted atomic theory a century earlier.

Einstein's statistical explanation of Brownian motion (the random movement of microscopic particles mixed in with pollen) is sometimes credited with helping to confirm the atomic theory at a time when some scientists argued against it.<ref>Cassidy, David (2004). [http://www.aip.org/history/einstein/essay-brownian.htm "Einstein on Brownian motion"].  [http://www.aip.org/history/einstein/great1.htm American Institute of Physics/AIP Center for History of Physics/Albert Einstein-Image and Impact/The Great Works I].  Retrieved on January 24, 2014.</ref> Most scientists had accepted atomic theory a century earlier.

Einstein also published a heuristic explanation of the photoelectric effect in which light has particle like properties as well as wave like properties. According to [[Maxwell's Equations]], light is a wave so one might expect that increasing the intensity of light should increase the number of electrons emitted from metal. The German physicist Lénard did an experiment proving that this was not true. Einstein argued that the experiment was consistent with [[Max Planck]]'s hypothesis that light is quantized and different particles of light or photons have different frequencies. Therefore, increasing the intensity of low frequency photons has no effect, while using a higher (blue or ultra violet) frequency of light does cause more electrons to be emitted. The formula Einstein used to explain this was Planck's formula ''e'' = ''hf'', where ''h'' is Planck's constant and ''f'' is the frequency.<ref>Davis, Warren, PhD. (2008 or before).  [http://www.physlink.com/Education/AskExperts/ae24.cfm?CFID=8792067&CFTOKEN=36662276 "What is the photoelectric effect?"]  PhysLink.com.  Retrieved on January 24, 2015.</ref>

Einstein also published a heuristic explanation of the photoelectric effect in which light has particle-like properties as well as wave like properties. According to [[Maxwell's Equations]], light is a wave so one might expect that increasing the intensity of light should increase the number of electrons emitted from metal. The German physicist Lénard did an experiment proving that this was not true. Einstein argued that the experiment was consistent with [[Max Planck]]'s hypothesis that light is quantized and different particles of light or photons have different frequencies. Therefore, increasing the intensity of low frequency photons has no effect, while using a higher (blue or ultra violet) frequency of light does cause more electrons to be emitted. The formula Einstein used to explain this was Planck's formula ''e'' = ''hf'', where ''h'' is Planck's constant and ''f'' is the frequency.<ref>Davis, Warren, PhD. (2008 or before).  [http://www.physlink.com/Education/AskExperts/ae24.cfm?CFID=8792067&CFTOKEN=36662276 "What is the photoelectric effect?"]  PhysLink.com.  Retrieved on January 24, 2015.</ref>

Although Einstein won a Nobel Prize for explaining the photoelectric effect, Lénard was critical of his accomplishments.<ref>Evans, Richard J. (2005).  ''The Third Reich in Power'' (London:  Penguin Books), pp. 306-309.</ref> Planck and Lénard had already received Nobel Prizes for related work explaining the photoelectric effect.

Although Einstein won a Nobel Prize for explaining the photoelectric effect, Lénard was critical of his accomplishments.<ref>Evans, Richard J. (2005).  ''The Third Reich in Power'' (London:  Penguin Books), pp. 306-309.</ref> Planck and Lénard had already received Nobel Prizes for related work explaining the photoelectric effect.