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      <subfield code="a">Campoamor Stursberg, Otto-Rudwig</subfield>
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      <subfield code="a">Low, S. G.</subfield>
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   <datafield ind2=" " ind1=" " tag="260">
      <subfield code="c">2009</subfield>
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      <subfield code="a">Given a semidirect product g = s ⊎ r of semisimple Lie algebras s and solvable algebras r, we construct polynomial operators in the enveloping algebra U(g) of g that commute with r and transform like the generators of s, up to a functional factor that turns out to be a Casimir operator of r. Such operators are said to generate a virtual copy of s in U(g), and allow to compute the Casimir operators of g in closed form, using the classical formulae for the invariants of s. The behavior of virtual copies
with respect to contractions of Lie algebras is analyzed. Applications to the class of Hamilton algebras and their inhomogeneous extensions are given.</subfield>
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      <subfield code="a">1751-8113</subfield>
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      <subfield code="a">10.1088/1751-8113/42/6/065205</subfield>
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      <subfield code="a">https://hdl.handle.net/20.500.14352/43785</subfield>
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      <subfield code="a">https//doi.org/10.1088/1751-8113/42/6/065205</subfield>
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      <subfield code="a">http://iopscience.iop.org/1751-8121/42/6/065205/</subfield>
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      <subfield code="a">Virtual copies of semisimple Lie algebras in enveloping algebras of semidirect products and Casimir operators</subfield>
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