115:
1324:
378:
33:
2039:
1312:
101:
340:, and it is conceivable – though much less certain – that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory. However, such bombs might very well prove to be too heavy for transportation by air.
607:
208:. However, Szilard had not been able to achieve a neutron-driven chain reaction with neutron-rich light atoms. In theory, if the number of secondary neutrons produced in a neutron-driven chain reaction was greater than one, then each such reaction could trigger multiple additional reactions, producing an exponentially increasing number of reactions.
324:, Janet Coatesworth. She later recalled that when Szilard mentioned extremely powerful bombs, she "was sure she was working for a nut". Ending the letter with "Yours truly, Albert Einstein" did nothing to alter this impression. Both the English letter and a longer explanatory letter were then posted to Einstein for him to sign.
335:
in France as well as Fermi and
Szilard in America – that it may become possible to set up a nuclear chain reaction in a large mass of uranium, by which vast amounts of power and large quantities of new radium-like elements would be generated. Now it appears almost certain that this could be achieved
312:
had reported that the prospects for building an atomic bomb were remote. He told
Szilard that he would deliver the letter, but suggested that it come from someone more prestigious. For Szilard, Einstein was again the obvious choice. Sachs and Szilard drafted a letter riddled with spelling errors and
530:, Einstein later regretted signing the letter because it led to the development and use of the atomic bomb in combat, adding that Einstein had justified his decision because of the greater danger that Nazi Germany would develop the bomb first. In 1947 Einstein told
348:
I understand that
Germany has actually stopped the sale of uranium from the Czechoslovakian mines which she has taken over. That she should have taken such early action might perhaps be understood on the ground that the son of the German Under-Secretary of State,
282:("I did not even think about that"). Einstein dictated a letter in German to the Belgian Ambassador to the United States. Wigner wrote it down, and Einstein agreed and signed it. At Wigner's suggestion, they also prepared a letter for the
440:. Szilard drafted a fourth letter for Einstein's signature that urged the President to meet with Szilard to discuss policy on nuclear energy. Dated March 25, 1945, it did not reach Roosevelt before his death on April 12, 1945.
385:
The
Einstein–Szilard letter was signed by Einstein and posted back to Szilard, who received it on August 9. Szilard gave both the short and long letters, along with a letter of his own, to Sachs on August 15. Sachs asked the
514:
leanings and celebrity status made him a security risk. At least one source states that
Einstein did clandestinely contribute some equations to the Manhattan Project. Einstein was allowed to work as a consultant to the
234:
them. Szilard then suggested using carbon as a moderator. They then needed large quantities of carbon and uranium to create a reactor. Szilard was convinced that they would succeed if they could get the materials.
1914:
405:
Sachs delayed his appointment until
October so that the President would give the letter due attention, securing an appointment on October 11. On that date he met with the President, the President's secretary,
460:), with Adamson and Hoover as its other members. It convened for the first time on October 21. The meeting was also attended by Fred L. Mohler from the Bureau of Standards, Richard B. Roberts of the
475:
The
Advisory Committee on Uranium was the beginning of the US government's effort to develop an atomic bomb, but it did not vigorously pursue the development of a weapon. It was superseded by the
320:, to do the driving. After receiving the draft, Einstein dictated the letter first in German. On returning to Columbia University, Szilard dictated the letter in English to a young departmental
1976:
1070:
464:, and Szilard, Teller and Wigner. Adamson was skeptical about the prospect of building an atomic bomb, but was willing to authorize $ 6,000 ($ 100,000 in current USD) for the purchase of
196:
which could yield vast amounts of energy for electric power generation or atomic bombs. He had first formulated and patented such an idea while he lived in London in 1933 after reading
226:, as Fermi maintained. Fermi and Szilard conducted a series of experiments and concluded that a chain reaction in natural uranium could be possible if they could find a suitable
998:
2086:
1092:
457:
429:
1929:
480:
561:
1494:
1356:
2066:
1821:
84:
316:
Szilard also set out himself for Long Island again on August 2. Wigner was unavailable, so this time
Szilard co-opted another Hungarian physicist,
1062:
432:
and a chosen representative of the Army and Navy to thoroughly investigate the possibilities of your suggestion regarding the element of uranium.
242:
published two influential articles on the exploitation of nuclear energy in 1939. After discussing this prospect with fellow
Hungarian physicist
605:, Leo Szilard, "Improvements in or relating to the transmutation of chemical elements", published 1949-09-28, issued 1936-03-30
491:
eventually prompted
Roosevelt to authorize a full-scale development effort in January 1942. The work of fission research was taken over by the
1253:
1227:
1196:
566:
492:
79:
and suggested that the United States should start its own nuclear program. It prompted action by Roosevelt, which eventually resulted in the
390:
staff for an appointment to see President Roosevelt, but before one could be set up, the administration became embroiled in a crisis due to
476:
461:
414:
1288:
907:
1374:
407:
289:
This still left the problem of getting government support for uranium research. Another friend of Szilard's, the Austrian economist
421:
Gilbert C. Hoover. Roosevelt summed up the conversation as: "Alex, what you are after is to see that the Nazis don't blow us up."
350:
994:
361:
At the time of the letter, the estimated material necessary for a fission chain reaction was several tons. Seven months later a
2076:
1349:
1040:
298:
53:
845:
550:
484:
1036:
449:
1302:
1103:
1981:
536:
magazine that "had I known that the Germans would not succeed in developing an atomic bomb, I would have done nothing."
142:
169:
brought the news to the United States, and the U.S. opened the Fifth Washington Conference on Theoretical Physics with
332:
2081:
2042:
1342:
114:
1924:
1919:
1328:
1316:
752:
418:
395:
362:
2061:
2006:
1539:
1398:
523:. He had no knowledge of the atomic bomb's development, and no influence on the decision of any being used.
410:
211:
Szilard collaborated with Fermi to build a nuclear reactor from natural uranium at Columbia University, where
173:
on January 26, 1939. The results were quickly corroborated by experimental physicists, most notably Fermi and
2071:
2001:
1898:
1453:
676:
354:
147:
1780:
1448:
1443:
1438:
1413:
650:
Die Ausnutzung der Atomenergie. Vom Laboratoriumsversuch zur Uranmaschine – Forschungsergebnisse in Dahlem
238:
Szilard was concerned that German scientists might also attempt this experiment. German nuclear physicist
193:
1120:
436:
Einstein sent two more letters to Roosevelt, on March 7, 1940, and April 25, 1940, calling for action on
2021:
1846:
1589:
1534:
301:
259:
56:
546:
Alexander Sachs' role in bringing President Roosevelt's attention to the possibility of an atomic bomb
1831:
1826:
1685:
1559:
1176:
685:
602:
278:, where Einstein was staying. When they explained the possibility of atomic bombs, Einstein replied:
255:
1690:
1645:
1605:
1428:
1293:
667:
645:
271:
239:
178:
286:
explaining what they were doing and why, giving it two weeks to respond if it had any objections.
1755:
1579:
1549:
1489:
1167:
1163:
701:
520:
516:
496:
453:
258:. Szilard knew Einstein well; between 1926 and 1930, he had worked with Einstein to develop the
1970:
1959:
1866:
1770:
1725:
1720:
1670:
1519:
1514:
1504:
1365:
1259:
1249:
1223:
1202:
1192:
1151:
500:
227:
197:
80:
1991:
1790:
1775:
1740:
1715:
1569:
1524:
1184:
693:
571:
558:, who wrote a similar letter to the Soviet leadership to start their atomic research program
437:
428:
I found this data of such import that I have convened a Board consisting of the head of the
309:
283:
215:
headed the physics department. There was disagreement about whether fission was produced by
212:
161:
138:
377:
32:
1996:
1836:
1800:
1730:
1665:
1655:
1630:
1529:
1509:
1484:
1143:
903:
545:
294:
251:
231:
174:
156:
120:
49:
1745:
304:. Sachs told Szilard that he had already spoken to the President about uranium, but that
1282:
1180:
689:
1939:
1934:
1705:
1650:
1640:
1635:
1554:
1479:
1408:
555:
488:
290:
17:
448:
Roosevelt decided that the letter required action, and authorized the creation of the
331:
In the course of the last four months it has been made probable – through the work of
2055:
1954:
1816:
1785:
1765:
1710:
1700:
1610:
1499:
1474:
1418:
1216:
527:
507:
366:
317:
247:
243:
68:
64:
705:
336:
in the immediate future. This new phenomenon would also lead to the construction of
200:'s disparaging remarks about generating power from his team's 1932 experiment using
2011:
1893:
1750:
1695:
1675:
1660:
1564:
1388:
1032:
399:
321:
305:
170:
152:
72:
1169:
The New World, 1939–1946 (A History of the United States Atomic Energy Commission)
837:
1841:
1795:
1760:
1735:
1680:
1584:
1574:
1458:
387:
337:
275:
220:
216:
185:
106:
76:
45:
219:, which made up less than one percent of natural uranium, or the more abundant
1944:
1888:
1625:
1615:
1544:
734:
499:
in June 1942, which directed an all-out bomb development program known as the
369:
to be less than 10 kilograms, making delivery of a bomb by air a possibility.
166:
60:
1206:
1986:
1852:
1620:
1423:
1263:
230:. They found that the hydrogen atoms in water slowed neutrons but tended to
134:
1155:
357:
in Berlin where some of the American work on uranium is now being repeated.
1246:
The Martians of Science: Five Physicists Who Changed the Twentieth Century
1218:
Genius in the Shadows: A Biography of Leo Szilárd: The Man Behind The Bomb
2026:
1859:
1393:
1125:
532:
511:
469:
100:
2016:
1883:
904:"President Roosevelt's response to Dr. Einstein Letter, Atomic Archive"
697:
465:
391:
327:
The letter dated August 2 and addressed to President Roosevelt warned:
223:
205:
189:
128:
The letter was conceived and written by Szilard, and signed by Einstein
1188:
748:
672:
Kann der Energieinhalt der Atomkerne technisch nutzbar gemacht werden?
1402:
1175:. Vol. 1. University Park: Pennsylvania State University Press.
772:
770:
201:
165:. This generated intense interest among physicists. Danish physicist
1334:
1277:
838:"Albert Einstein's Letters to President Franklin Delano Roosevelt"
717:
715:
376:
31:
813:
811:
809:
1964:
1433:
832:
830:
828:
826:
1338:
1063:"Prof. Einstein Working on Explosives for U.S. Navy Department"
510:
denied him the work clearance needed in July 1940, saying his
270:
On July 12, 1939, Szilard and Wigner drove in Wigner's car to
506:
Einstein did not work on the Manhattan Project. The Army and
424:
Roosevelt sent a reply thanking Einstein, and informing him:
250:
was the best source of uranium ore. Wigner suggested that
246:, they decided that they should warn the Belgians, as the
85:
use of these bombs on the cities of Hiroshima and Nagasaki
456:, the Director of the Bureau of Standards (currently the
192:-driven fission of heavy atoms could be used to create a
254:
might be a suitable person to do this, as he knew the
1300:
83:, the development of the first atomic bombs, and the
1907:
1876:
1809:
1598:
1467:
1381:
27:
1939 letter to U.S. president Franklin D. Roosevelt
1283:Roosevelt correspondence with Einstein and Szilárd
1215:
59:. Written by Szilard in consultation with fellow
976:
964:
952:
940:
928:
890:
878:
817:
800:
788:
776:
721:
632:
620:
589:
426:
346:
329:
1093:"Scientist Tells of Einstein's A-bomb Regrets"
458:National Institute of Standards and Technology
1350:
481:Office of Scientific Research and Development
8:
1278:Reproduction of 1939 Einstein–Szilárd letter
562:List of most expensive books and manuscripts
145:in uranium in the January 6, 1939, issue of
1289:Einstein and Szilard re-enact their meeting
344:It also specifically warned about Germany:
1357:
1343:
1335:
1214:Lanouette, William; Silard, Bela (1992).
36:Facsimile of the Einstein–Szilard letter
2087:August 1939 events in the United States
1307:
1001:from the original on September 22, 2013
989:
987:
985:
749:"Leo Szilard the Inventor: A Slideshow"
582:
1121:"Einstein, the Man Who Started It All"
1073:from the original on December 12, 2013
997:. American Museum of Natural History.
866:
656:(in German). No. 387, Supplement.
1222:. New York: Charles Scribner's Sons.
910:from the original on October 22, 2013
567:Nuclear weapons and the United States
493:United States Army Corps of Engineers
7:
1148:Britain and Atomic Energy, 1935–1945
755:from the original on August 20, 2020
472:for Szilard and Fermi's experiment.
52:on August 2, 1939, that was sent to
1248:. Oxford: Oxford University Press.
1043:from the original on March 30, 2014
848:from the original on April 17, 2012
477:National Defense Research Committee
1822:Bombings of Hiroshima and Nagasaki
462:Carnegie Institution of Washington
280:"Daran habe ich gar nicht gedacht"
159:in the February 11, 1939 issue of
25:
747:Dannen, Gene (February 9, 1998).
413:, and two ordnance experts, Army
2067:History of the Manhattan Project
2038:
2037:
1322:
1310:
1285:, FDR library, Marist University
1150:. London: Macmillan Publishing.
1033:"Einstein Exhibit – Nuclear Age"
113:
99:
452:. The committee was chaired by
1102:. May 13, 1955. Archived from
54:President of the United States
1:
1166:; Anderson, Oscar E. (1962).
1037:American Institute of Physics
450:Advisory Committee on Uranium
365:would estimate the necessary
1982:Oppenheimer security hearing
143:discovery of nuclear fission
977:Hewlett & Anderson 1962
965:Hewlett & Anderson 1962
953:Hewlett & Anderson 1962
941:Hewlett & Anderson 1962
929:Hewlett & Anderson 1962
891:Hewlett & Anderson 1962
879:Lanouette & Silard 1992
818:Lanouette & Silard 1992
801:Lanouette & Silard 1992
789:Lanouette & Silard 1992
777:Lanouette & Silard 1992
722:Hewlett & Anderson 1962
654:Deutsche Allgemeine Zeitung
633:Hewlett & Anderson 1962
621:Lanouette & Silard 1992
590:Hewlett & Anderson 1962
2103:
1244:Hargittai, István (2006).
1022:, National Geographic 2017
417:Keith F. Adamson and Navy
2035:
1925:Bismuth phosphate process
1920:Atomic Energy Act of 1946
1372:
1100:The Philadelphia Bulletin
1067:Jewish Telegraphic Agency
551:Frisch–Peierls memorandum
485:Frisch–Peierls memorandum
71:, the letter warned that
293:, suggested approaching
44:was a letter written by
2002:S-1 Executive Committee
1950:Einstein–Szilard letter
1020:Genius, Albert Einstein
995:"The Manhattan Project"
677:Die Naturwissenschaften
363:breakthrough in Britain
355:Kaiser-Wilhelm-Institut
313:mailed it to Einstein.
148:Die Naturwissenschaften
42:Einstein–Szilard letter
18:Einstein-Szilárd letter
2077:World War II documents
1444:Salt Wells Pilot Plant
479:in 1940, and then the
434:
382:
359:
342:
194:nuclear chain reaction
37:
2022:X-10 Graphite Reactor
1977:Nobel Prize laureates
1847:509th Composite Group
735:U.S. patent 1,781,541
380:
353:, is attached to the
302:Franklin D. Roosevelt
260:Einstein refrigerator
57:Franklin D. Roosevelt
35:
1930:British contribution
1832:Operation Peppermint
1827:Operation Crossroads
1686:Maria Goeppert Mayer
1109:on November 8, 2006.
648:(August 15, 1939). "
603:GB patent 630726
297:, who had access to
256:Belgian royal family
184:Hungarian physicist
1691:George Kistiakowsky
1646:Charles Critchfield
1181:1962PhT....15l..62H
1164:Hewlett, Richard G.
803:, pp. 200–201.
779:, pp. 198–200.
690:1939NW.....27..402F
623:, pp. 132–136.
430:Bureau of Standards
179:Columbia University
1756:Henry DeWolf Smyth
1535:Robert Oppenheimer
1490:Priscilla Duffield
1329:History of science
1317:Nuclear technology
906:. Atomic Archive.
698:10.1007/BF01489507
684:(23/24): 402–410.
521:Bureau of Ordnance
517:United States Navy
497:Manhattan District
454:Lyman James Briggs
415:Lieutenant Colonel
396:invasion of Poland
383:
188:realized that the
38:
2082:Letters (message)
2049:
2048:
1971:Los Alamos Primer
1960:Interim Committee
1915:African Americans
1867:The Great Artiste
1726:Isidor Isaac Rabi
1721:Norman Ramsey Jr.
1520:Franklin Matthias
1459:Heavy water sites
1366:Manhattan Project
1255:978-0-19-517845-6
1229:978-0-684-19011-2
1198:978-0-520-07186-5
1189:10.1063/1.3057919
1129:. March 10, 1947.
1069:. June 16, 1943.
943:, pp. 24–26.
931:, pp. 20–21.
869:, pp. 40–45.
724:, pp. 15–16.
668:Flügge, Siegfried
646:Flügge, Siegfried
635:, pp. 13–14.
592:, pp. 10–13.
501:Manhattan Project
411:Edwin "Pa" Watson
408:Brigadier General
381:Roosevelt's reply
228:neutron moderator
198:Ernest Rutherford
155:identified it as
81:Manhattan Project
16:(Redirected from
2094:
2041:
2040:
1992:Quebec Agreement
1776:John von Neumann
1716:George B. Pegram
1525:Dorothy McKibbin
1359:
1352:
1345:
1336:
1327:
1326:
1325:
1315:
1314:
1313:
1306:
1267:
1233:
1221:
1210:
1174:
1159:
1144:Gowing, Margaret
1131:
1130:
1117:
1111:
1110:
1108:
1097:
1089:
1083:
1082:
1080:
1078:
1059:
1053:
1052:
1050:
1048:
1029:
1023:
1017:
1011:
1010:
1008:
1006:
991:
980:
974:
968:
962:
956:
950:
944:
938:
932:
926:
920:
919:
917:
915:
900:
894:
888:
882:
876:
870:
864:
858:
857:
855:
853:
834:
821:
815:
804:
798:
792:
786:
780:
774:
765:
764:
762:
760:
744:
738:
737:
731:
725:
719:
710:
709:
664:
658:
657:
642:
636:
630:
624:
618:
612:
611:
610:
606:
599:
593:
587:
572:Szilard petition
487:and the British
438:nuclear research
398:, which started
284:State Department
240:Siegfried Flügge
213:George B. Pegram
139:Fritz Strassmann
117:
103:
21:
2102:
2101:
2097:
2096:
2095:
2093:
2092:
2091:
2062:Albert Einstein
2052:
2051:
2050:
2045:
2031:
1997:RaLa Experiment
1903:
1872:
1837:Project Alberta
1805:
1801:Chien-Shiung Wu
1731:James Rainwater
1666:Richard Feynman
1656:John R. Dunning
1631:Norris Bradbury
1594:
1580:Stafford Warren
1550:William Purnell
1530:Kenneth Nichols
1510:Ernest Lawrence
1485:James B. Conant
1463:
1377:
1368:
1363:
1333:
1323:
1321:
1311:
1309:
1301:
1274:
1256:
1243:
1240:
1238:Further reading
1230:
1213:
1199:
1172:
1162:
1142:
1139:
1134:
1119:
1118:
1114:
1106:
1095:
1091:
1090:
1086:
1076:
1074:
1061:
1060:
1056:
1046:
1044:
1031:
1030:
1026:
1018:
1014:
1004:
1002:
993:
992:
983:
975:
971:
963:
959:
951:
947:
939:
935:
927:
923:
913:
911:
902:
901:
897:
889:
885:
877:
873:
865:
861:
851:
849:
836:
835:
824:
816:
807:
799:
795:
787:
783:
775:
768:
758:
756:
746:
745:
741:
733:
732:
728:
720:
713:
666:
665:
661:
644:
643:
639:
631:
627:
619:
615:
608:
601:
600:
596:
588:
584:
580:
542:
446:
375:
295:Alexander Sachs
268:
252:Albert Einstein
175:John R. Dunning
157:nuclear fission
132:
131:
130:
129:
125:
124:
123:
121:Albert Einstein
118:
110:
109:
104:
93:
50:Albert Einstein
28:
23:
22:
15:
12:
11:
5:
2100:
2098:
2090:
2089:
2084:
2079:
2074:
2072:1939 documents
2069:
2064:
2054:
2053:
2047:
2046:
2036:
2033:
2032:
2030:
2029:
2024:
2019:
2014:
2009:
2004:
1999:
1994:
1989:
1984:
1979:
1974:
1967:
1962:
1957:
1952:
1947:
1942:
1940:Chicago Pile-1
1937:
1935:Calutron Girls
1932:
1927:
1922:
1917:
1911:
1909:
1908:Related topics
1905:
1904:
1902:
1901:
1896:
1891:
1886:
1880:
1878:
1874:
1873:
1871:
1870:
1863:
1856:
1849:
1844:
1839:
1834:
1829:
1824:
1819:
1813:
1811:
1807:
1806:
1804:
1803:
1798:
1793:
1788:
1783:
1778:
1773:
1771:Stanisław Ulam
1768:
1763:
1758:
1753:
1748:
1743:
1738:
1733:
1728:
1723:
1718:
1713:
1708:
1706:Edwin McMillan
1703:
1698:
1693:
1688:
1683:
1678:
1673:
1668:
1663:
1658:
1653:
1651:Harry Daghlian
1648:
1643:
1641:John Cockcroft
1638:
1636:James Chadwick
1633:
1628:
1623:
1618:
1613:
1608:
1602:
1600:
1596:
1595:
1593:
1592:
1587:
1582:
1577:
1572:
1567:
1562:
1560:Charles Thomas
1557:
1555:Frank Spedding
1552:
1547:
1542:
1537:
1532:
1527:
1522:
1517:
1515:James Marshall
1512:
1507:
1502:
1497:
1495:Thomas Farrell
1492:
1487:
1482:
1480:Arthur Compton
1477:
1471:
1469:
1468:Administrators
1465:
1464:
1462:
1461:
1456:
1451:
1446:
1441:
1436:
1431:
1426:
1421:
1416:
1411:
1406:
1396:
1391:
1385:
1383:
1379:
1378:
1373:
1370:
1369:
1364:
1362:
1361:
1354:
1347:
1339:
1332:
1331:
1319:
1299:
1298:
1286:
1280:
1273:
1272:External links
1270:
1269:
1268:
1254:
1239:
1236:
1235:
1234:
1228:
1211:
1197:
1160:
1138:
1135:
1133:
1132:
1112:
1084:
1054:
1024:
1012:
981:
969:
957:
945:
933:
921:
895:
883:
881:, p. 207.
871:
859:
822:
820:, p. 202.
805:
793:
791:, p. 199.
781:
766:
739:
726:
711:
659:
637:
625:
613:
594:
581:
579:
576:
575:
574:
569:
564:
559:
556:Georgy Flyorov
553:
548:
541:
538:
445:
442:
374:
371:
351:von Weizsäcker
291:Gustav Stolper
274:on New York's
267:
264:
127:
126:
119:
112:
111:
105:
98:
97:
96:
95:
94:
92:
89:
75:might develop
48:and signed by
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2099:
2088:
2085:
2083:
2080:
2078:
2075:
2073:
2070:
2068:
2065:
2063:
2060:
2059:
2057:
2044:
2034:
2028:
2025:
2023:
2020:
2018:
2015:
2013:
2010:
2008:
2005:
2003:
2000:
1998:
1995:
1993:
1990:
1988:
1985:
1983:
1980:
1978:
1975:
1973:
1972:
1968:
1966:
1963:
1961:
1958:
1956:
1955:Franck Report
1953:
1951:
1948:
1946:
1943:
1941:
1938:
1936:
1933:
1931:
1928:
1926:
1923:
1921:
1918:
1916:
1913:
1912:
1910:
1906:
1900:
1897:
1895:
1892:
1890:
1887:
1885:
1882:
1881:
1879:
1875:
1869:
1868:
1864:
1862:
1861:
1857:
1855:
1854:
1850:
1848:
1845:
1843:
1840:
1838:
1835:
1833:
1830:
1828:
1825:
1823:
1820:
1818:
1817:Alsos Mission
1815:
1814:
1812:
1808:
1802:
1799:
1797:
1794:
1792:
1791:Robert Wilson
1789:
1787:
1786:Eugene Wigner
1784:
1782:
1779:
1777:
1774:
1772:
1769:
1767:
1766:Edward Teller
1764:
1762:
1759:
1757:
1754:
1752:
1749:
1747:
1744:
1742:
1741:Glenn Seaborg
1739:
1737:
1734:
1732:
1729:
1727:
1724:
1722:
1719:
1717:
1714:
1712:
1711:Mark Oliphant
1709:
1707:
1704:
1702:
1701:Willard Libby
1699:
1697:
1694:
1692:
1689:
1687:
1684:
1682:
1679:
1677:
1674:
1672:
1669:
1667:
1664:
1662:
1659:
1657:
1654:
1652:
1649:
1647:
1644:
1642:
1639:
1637:
1634:
1632:
1629:
1627:
1624:
1622:
1619:
1617:
1614:
1612:
1611:Robert Bacher
1609:
1607:
1604:
1603:
1601:
1597:
1591:
1590:Roscoe Wilson
1588:
1586:
1583:
1581:
1578:
1576:
1573:
1571:
1568:
1566:
1563:
1561:
1558:
1556:
1553:
1551:
1548:
1546:
1543:
1541:
1538:
1536:
1533:
1531:
1528:
1526:
1523:
1521:
1518:
1516:
1513:
1511:
1508:
1506:
1505:John Lansdale
1503:
1501:
1500:Leslie Groves
1498:
1496:
1493:
1491:
1488:
1486:
1483:
1481:
1478:
1476:
1475:Vannevar Bush
1473:
1472:
1470:
1466:
1460:
1457:
1455:
1452:
1450:
1447:
1445:
1442:
1440:
1437:
1435:
1432:
1430:
1427:
1425:
1422:
1420:
1417:
1415:
1412:
1410:
1407:
1404:
1400:
1397:
1395:
1392:
1390:
1387:
1386:
1384:
1380:
1376:
1371:
1367:
1360:
1355:
1353:
1348:
1346:
1341:
1340:
1337:
1330:
1320:
1318:
1308:
1304:
1296:
1295:
1291:for the film
1290:
1287:
1284:
1281:
1279:
1276:
1275:
1271:
1265:
1261:
1257:
1251:
1247:
1242:
1241:
1237:
1231:
1225:
1220:
1219:
1212:
1208:
1204:
1200:
1194:
1190:
1186:
1182:
1178:
1171:
1170:
1165:
1161:
1157:
1153:
1149:
1145:
1141:
1140:
1136:
1128:
1127:
1122:
1116:
1113:
1105:
1101:
1094:
1088:
1085:
1072:
1068:
1064:
1058:
1055:
1042:
1038:
1034:
1028:
1025:
1021:
1016:
1013:
1000:
996:
990:
988:
986:
982:
979:, p. 75.
978:
973:
970:
967:, p. 49.
966:
961:
958:
955:, p. 41.
954:
949:
946:
942:
937:
934:
930:
925:
922:
909:
905:
899:
896:
893:, p. 17.
892:
887:
884:
880:
875:
872:
868:
863:
860:
847:
843:
839:
833:
831:
829:
827:
823:
819:
814:
812:
810:
806:
802:
797:
794:
790:
785:
782:
778:
773:
771:
767:
754:
750:
743:
740:
736:
730:
727:
723:
718:
716:
712:
707:
703:
699:
695:
691:
687:
683:
680:(in German).
679:
678:
673:
669:
663:
660:
655:
651:
647:
641:
638:
634:
629:
626:
622:
617:
614:
604:
598:
595:
591:
586:
583:
577:
573:
570:
568:
565:
563:
560:
557:
554:
552:
549:
547:
544:
543:
539:
537:
535:
534:
529:
528:Linus Pauling
526:According to
524:
522:
518:
513:
509:
508:Vannevar Bush
504:
502:
498:
494:
490:
486:
483:in 1941. The
482:
478:
473:
471:
467:
463:
459:
455:
451:
443:
441:
439:
433:
431:
425:
422:
420:
416:
412:
409:
403:
401:
397:
393:
389:
379:
372:
370:
368:
367:critical mass
364:
358:
356:
352:
345:
341:
339:
334:
328:
325:
323:
319:
318:Edward Teller
314:
311:
307:
303:
300:
296:
292:
287:
285:
281:
277:
273:
265:
263:
261:
257:
253:
249:
248:Belgian Congo
245:
244:Eugene Wigner
241:
236:
233:
229:
225:
222:
218:
214:
209:
207:
203:
199:
195:
191:
187:
182:
180:
176:
172:
168:
164:
163:
158:
154:
150:
149:
144:
141:reported the
140:
136:
122:
116:
108:
102:
90:
88:
86:
82:
78:
74:
70:
69:Eugene Wigner
66:
65:Edward Teller
62:
58:
55:
51:
47:
43:
34:
30:
19:
2027:Y-12 Project
2012:Smyth Report
2007:S-50 Project
1969:
1965:K-25 Project
1949:
1894:Pumpkin bomb
1865:
1858:
1851:
1781:John Wheeler
1751:Louis Slotin
1746:Emilio Segrè
1696:George Koval
1676:James Franck
1661:Enrico Fermi
1606:Luis Alvarez
1565:Paul Tibbets
1540:Deak Parsons
1294:Atomic Power
1292:
1245:
1217:
1168:
1147:
1124:
1115:
1104:the original
1099:
1087:
1075:. Retrieved
1066:
1057:
1045:. Retrieved
1027:
1019:
1015:
1003:. Retrieved
972:
960:
948:
936:
924:
912:. Retrieved
898:
886:
874:
862:
850:. Retrieved
841:
796:
784:
757:. Retrieved
742:
729:
681:
675:
671:
662:
653:
649:
640:
628:
616:
597:
585:
531:
525:
505:
489:Maud Reports
474:
447:
435:
427:
423:
404:
400:World War II
384:
360:
347:
343:
330:
326:
322:stenographer
315:
288:
279:
269:
237:
210:
183:
171:Enrico Fermi
160:
153:Lise Meitner
146:
133:
77:atomic bombs
41:
39:
29:
1842:Silverplate
1796:Leona Woods
1761:Leo Szilard
1736:Bruno Rossi
1681:Klaus Fuchs
1585:Ed Westcott
1575:Harold Urey
867:Gowing 1964
388:White House
276:Long Island
221:uranium-238
217:uranium-235
186:Leo Szilard
107:Leo Szilard
63:physicists
46:Leo Szilard
2056:Categories
1945:Demon core
1889:Little Boy
1810:Operations
1626:Niels Bohr
1616:Hans Bethe
1599:Scientists
1545:Boris Pash
1424:Los Alamos
1137:References
1077:October 9,
1047:October 9,
1005:October 9,
914:October 9,
852:October 9,
266:The letter
167:Niels Bohr
1987:Plutonium
1853:Enola Gay
1671:Val Fitch
1621:Aage Bohr
1570:Bud Uanna
1439:Oak Ridge
1207:637004643
670:(1939). "
419:Commander
299:President
272:Cutchogue
204:to split
135:Otto Hahn
61:Hungarian
2043:Category
1899:Thin Man
1860:Bockscar
1454:Wendover
1434:New York
1429:Montreal
1419:Inyokern
1394:Berkeley
1375:Timeline
1264:62084304
1146:(1964).
1126:Newsweek
1071:Archived
1041:Archived
999:Archived
908:Archived
846:Archived
844:. 1997.
753:Archived
706:40646390
540:See also
533:Newsweek
512:pacifist
470:graphite
373:Delivery
2017:Uranium
1884:Fat Man
1877:Weapons
1449:Trinity
1414:Hanford
1399:Chicago
1303:Portals
1177:Bibcode
1156:3195209
842:E-World
759:May 24,
686:Bibcode
466:uranium
444:Results
392:Germany
232:capture
224:isotope
206:lithium
202:protons
190:neutron
73:Germany
1409:Dayton
1403:Site A
1297:(1946)
1262:
1252:
1226:
1205:
1195:
1154:
704:
609:
333:Joliot
310:Pegram
162:Nature
151:, and
91:Origin
1382:Sites
1173:(PDF)
1107:(PDF)
1096:(PDF)
702:S2CID
578:Notes
338:bombs
306:Fermi
1389:Ames
1260:OCLC
1250:ISBN
1224:ISBN
1203:OCLC
1193:ISBN
1152:OCLC
1079:2013
1049:2013
1007:2013
916:2013
854:2013
761:2015
468:and
308:and
137:and
67:and
40:The
1185:doi
694:doi
674:".
652:".
519:'s
495:'s
402:.
394:'s
177:at
2058::
1258:.
1201:.
1191:.
1183:.
1123:.
1098:.
1065:.
1039:.
1035:.
984:^
840:.
825:^
808:^
769:^
751:.
714:^
700:.
692:.
682:27
503:.
262:.
181:.
87:.
1405:)
1401:(
1358:e
1351:t
1344:v
1305::
1266:.
1232:.
1209:.
1187::
1179::
1158:.
1081:.
1051:.
1009:.
918:.
856:.
763:.
708:.
696::
688::
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
