We re-explore the Bi-and Multi-Galileon models with trivial asymptotic conditions at infinity and show that propagation of superluminal fluctuations is a common and unavoidable feature of these theories, unlike previously claimed in the literature. We show that all Multi-Galileon theories containing a Cubic Galileon term exhibit superluminalities at large distances from a point source, and that even if the Cubic Galileon is not present one can always find sensible matter distributions in which there are superluminal modes at large distances. In the Bi-Galileon case we explicitly show that there are always superluminal modes around a point source even if the Cubic Galileon is not present. Finally, we briefly comment on the possibility of avoiding superluminalities by modifying the asymptotic conditions at infinity.

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We study the occurrence of global gauge anomalies in the coset models of two-dimensional conformal field theory that are based on gauged WZW models. A complete classification of the non-anomalous theories for a wide family of gauged rigid adjoint or twisted-adjoint symmetries of WZW models is achieved with the help of Dynkin's classification of Lie subalgebras of simple Lie algebras.Considering each subgroup Z and the corresponding values of a 1 , a 2 ,ã 1 , andã 2 , and recalling the admissible values (3.33) of the level, we deduce Proposition 3.10 The twisted coset models corresponding to Lie algebra g = so(8), outer automorphism ω 4 and arbitrary subalgebra do not have anomalies for Z =Z (+ theory) and Z = Z 1 , Z 2 or Z diag . The models with h = g and Z =Z (-theory) is anomalous.The results for the twist ω −1 4 may be deduced from the above proposition if we observe that ω −1 4 may be obtained from ω 4 by the conjugation by any cyclic outer automorphism ω ′ of order 2. Hence the conditions for the absence or the presence of anomalies for the theory twisted by ω −1 4 are as for the ones for the twist ω 4 except for the exchange of the ± theories for Z =Z and k odd leading to Proposition 3.11 The twisted coset models corresponding to Lie algebra g = so(8), outer automorphism ω −1 4 and arbitrary subalgebra do not have anomalies for Z =Z ((−) k theory) and Z = Z 1 , Z 2 or Z diag . The models with h = g, and Z =Z ((−) k+1 theory) is anomalous.This may be confirmed by a direct calculation. 9