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==Claims of experimental verification==

==Claims of experimental verification==

In an experiment which is replicated in courses on modern physics at colleges and universities around the world hundreds of times each year, in 1932 an English and an Irish physicist, John Cockcroft and Ernest Walton, as a byproduct of ''&quot;their pioneer work on the transmutation of atomic nuclei by artificially accelerated atomic particles&quot;''<ref>[http://www.nobelprize.org/nobel_prizes/physics/laureates/1951/# Nobel Prize Organization]</ref> for which they were honored with the [[Nobel Prize]] in physics in 1951.  Neither the Nobel Committee nor the prize recipients made any claim to verify ''E=mc&sup2;''.<ref>[http://www.nobelprize.org/nobel_prizes/physics/laureates/1951/cockcroft-lecture.pdf John D. Cockroft ''Experiments on the interaction of high-speed nucleons with atomic nuclei''], Nobel Lecture, Dec 11, 1951</ref>

In 1932 an English and an Irish physicist, John Cockcroft and Ernest Walton, performed the first artificial nuclear transmuation, an experiment which is replicated in courses on modern physics at colleges and universities around the world hundreds of times each year: ''&quot;their pioneer work on the transmutation of atomic nuclei by artificially accelerated atomic particles&quot;''<ref>[http://www.nobelprize.org/nobel_prizes/physics/laureates/1951/# Nobel Prize Organization]</ref> for which they were honored with the [[Nobel Prize]] in physics in 1951.  The equation was verified by that experiment, though neither the Nobel Committee nor the prize recipients made any claim to that effect.<ref>[http://www.nobelprize.org/nobel_prizes/physics/laureates/1951/cockcroft-lecture.pdf John D. Cockroft ''Experiments on the interaction of high-speed nucleons with atomic nuclei''], Nobel Lecture, Dec 11, 1951</ref>

They bombarded [[Lithium]] atoms with [[protons]] having a [[kinetic energy]] less than 1 [[Electron-Volts|MeV]]. The result were two (slightly less heavy) [[&alpha;-particle]]s, for which the [[kinetic energy]] was measured as 17.3 MeV

They bombarded [[Lithium]] atoms with [[protons]] having a [[kinetic energy]] less than 1 [[Electron-Volts|MeV]]. The result were two (slightly less heavy) [[&alpha;-particle]]s, for which the [[kinetic energy]] was measured as 17.3 MeV

Accurate measurements and detailed calculations allowed for verifying the theoretical values with an accuracy of ±0.5%. This was the first time a nucleus was artificially split, and thereby the first transmutation of elements using accelerated particles:

Accurate measurements and detailed calculations allowed for verifying the theoretical values with an accuracy of ±0.5%. This was the first time a nucleus was artificially split, and thereby the first transmutation of elements using accelerated particles:

Some claim that the best empirical verification of '''E=mc²''' was done in 2005 by Simon Rainville et al., as published in ''[[Nature (journal)|Nature]]'' (which is not a leading physics journal).<ref>[http://www.nature.com/nature/journal/v438/n7071/full/4381096a.html Nature 438, 1096-1097 (22 December 2005)] doi:10.1038/4381096a; Published online 21 December 2005</ref>  The authors state in their article in ''Nature'' magazine that &quot;Einstein's relationship is separately confirmed in two tests, which yield a combined result of 1−Δmc²/E=(−1.4±4.4)×10⁻⁷, indicating that it holds to a level of at least 0.00004%. To our knowledge, this is the most precise direct test of the famous equation yet described.&quot;

Some claim that the best empirical verification of '''E=mc²''' was done in 2005 by Simon Rainville et al., as published in ''[[Nature (journal)|Nature]]''<ref>[http://www.nature.com/nature/journal/v438/n7071/full/4381096a.html Nature 438, 1096-1097 (22 December 2005)] doi:10.1038/4381096a; Published online 21 December 2005</ref>. The authors state in their article in ''Nature'' magazine that &quot;Einstein's relationship is separately confirmed in two tests, which yield a combined result of 1−Δmc²/E=(−1.4±4.4)×10⁻⁷, indicating that it holds to a level of at least 0.00004%. To our knowledge, this is the most precise direct test of the famous equation yet described.&quot;

==A Famous Example -- Nuclear Fission of Uranium==

==A Famous Example -- Nuclear Fission of Uranium==