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A new approach to the study of nonrelativistic bosonic string in flat space time is introduced, basing on a holistic hamiltonian analysis of the minimal action for the string. This leads to a structurally new form of the action which is, however, equivalent to the known results since, under appropriate limits, it interpolates between the minimal action (Nambu Goto type) where the string metric is taken to be that induced by the embedding and the Polyakov type of action where the world sheet metric components are independent fields. The equivalence among different actions is established by a detailed study of symmetries using constraint analysis. Various vexing issues in the existing literature are clarified. The interpolating action mooted here is shown to reveal the geometry of the string and may be useful in analyzing nonrelativistic string coupled with curved background.
We obtain a new form for the action of a nonrelativistic particle coupled to Newtonian gravity. The result is different from that existing in the literature which, as shown here, is riddled with problems and inconsistencies. The present derivation is
We discuss equilibration process in expanding universes as compared to the thermalization process in Minkowski space--time. The final goal is to answer the following question: Is the equilibrium reached before the rapid expansion stops and quantum ef
The restoration of spin connection clarifies the long known local Lorentz invariance problem in telelparallel gravities. It is considered now that any tetrad together with the associated spin connection can be equally utilized. Among the tetrads ther
In this paper we consider a model for gravity in 4-dimensional space-time originally proposed by Chamseddine, which may be derived by dimensional reduction and truncation from a 5-dimensional Chern-Simons theory. Its topological origin makes it an in
Flat Space Cosmology (FSC) spacetimes are exact solutions of 3D gravity theories. In this work, we study phase transition between FSC spacetimes and Hot Flat Spacetimes (HFS) in general minimal massive gravity and exotic general massive gravity. We s