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Newton-Hooke spacetimes, Hpp-waves and the cosmological constant

G. W. Gibbons·C. E. Patricot
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Abstract

We show explicitly how the Newton-Hooke groups act as symmetries of the equations of motion of non-relativistic cosmological models with a cosmological constant. We give the action on the associated non-relativistic spacetimes and show how these may be obtained from a null reduction of 5-dimensional homogeneous pp-wave Lorentzian spacetimes. This allows us to realize the Newton-Hooke groups and their Bargmann type central extensions as subgroups of the isometry groups of the pp-wave spacetimes. The extended Schrodinger type conformal group is identified and its action on the equations of motion given. The non-relativistic conformal symmetries also have applications to time-dependent harmonic oscillators. Finally we comment on a possible application to Gao's generalization of the matrix model.

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G. W. Gibbons, C. E. Patricot. 2003-08-28. Newton-Hooke spacetimes, Hpp-waves and the cosmological constant. https://doi.org/10.1088/0264-9381%2F20%2F23%2F016

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