Dr. William Levison (seated, far left) with other U.S. Army medial doctors and nurses with Christmas Tree in background Portraits Groups

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Unterprima (eleventh grade) boys school class portrait Portraits Groups Men

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Embedding Of Non-Simple Lie-Groups, Coupling-Constant Relations And Non-Uniqueness Of Models Of Unification

A general derivation of the coupling constant relations which result on embedding a non-simple group like SU L (2) @ U(1) in a larger simple group (or graded Lie group) is given. It is shown that such relations depend only on the requirement (i) that the multiplet of vector fields form an irreducible representation of the unifying algebra and (ii) the transformation properties of the fermions under SU L (2). This point is illustrated in two ways, one by constructing two different unification groups containing the same fermions and therefore have same Weinberg angle; the other by putting different SU L (2) structures on the same fermions and consequently have different Weinberg angles. In particular the value sin~0=3/8 is characteristic of the sequential doublet models or models which invoke a large number of additional leptons like E 6, while addition of extra charged fermion singlets can reduce the value of sin ~ 0 to 1/4. We point out that at the present time the models of grand unification are far from unique.

Writer Clara Michelson (second from left) seated at an outdoor table with three unidentified women and one unidentified man; Saint-Brevin-les-Pins, France Portraits Groups

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Portrait of David Baumgardt with Marie Zweig Portraits Groups

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Leo Baeck sitting on grass with Rudolf Seligsohn; Erzgebirge Portraits; Groups; Men

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Hannah Karminski speaking with Mrs. Neuhaus; Conference of Juedisches Frauenbundes; Duerkheim Portraits Groups Women

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Alice Salomon with students on the roof garden of the Sozialen Frauenschule Portraits Groups

Including Hilde Caro, Lotte Lipschitz and Ellen Milch

Albert Einstein with unidentified group; City College, New York Portraits Groups; Men

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Group portrait, 50th Anniversary of the Saxony-Anhalt chapter of German Engineers; Bernburg Portraits Groups

Caption: Zur Erinnerung an das fuenfzigjaehrige Gruendungsfest Saechsisch Anhaltinischen Bezirksvereins Deutscher Ingenieure am 11. und 12. Mai 1912 in Bernburg.

Portrait from the Golden Wedding Anniversary celebration of Heinrich and Helena Valentin; Berlin Portraits Groups

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