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The cold dark matter paradigm has been posited as the standard explanation for the non-Keplerian behavior of galaxy rotation curves, where for galaxies satisfying the Tully-Fisher relation, the mass of the dark matter halo from a large class of universal dark matter profiles ought to roughly increase linearly with radial distance at large distances, $m(r) sim r/nG$ ($G$ is the gravitational constant and $n$ is a dimensionless parameter which depends on the amount of baryonic matter $M$ within the galaxy). Despite numerous advances in modeling galaxy formation and evolution, a scientific consensus on the origin of the observed dependence of the dimensionless parameter $n = (GMa_{0})^{-1/2}$ on the mass of baryonic matter $M$ within the galaxy (the Tully-Fisher relation), and the connection of the cosmological constant $Lambda$ to the parameter $a_{0} sim (Lambda/3)^{1/2}$ remains elusive. Here, we show that Einstein Field Equations can be remolded into $ abla_{ u}mathcal{K}^{ u}_{,,mu} = 8pi GMPsi^{*}mathcal{D}_{mu}Psi$, where $mathcal{K}_{mu u}$ is a complex Hermitian tensor, $mathcal{D}_{mu}$ is a covariant derivative and $Psi$ is a complex-valued function. This avails a novel constraint, $ abla_{mu} abla_{ u}mathcal{K}^{mu u} = 0$ not necessarily available in Einsteins General Relativity. In the weak-field regime, we can readily reproduce the Tully-Fisher relation using the usual charge-less pressure-less fluid. Moreover, our approach is equivalent to a Ginzburg-Landau theory of $n$ bosons, where the order parameter is normalized as $int_{0}^{1/a_{0}} dr,4pi r^2Psi^*Psi = n$ and $1/a_{0} sim (Lambda/3)^{-1/2}$ is the cut-off length scale comparable to the size of the de Sitter universe. Our investigations provide a framework that reproduces the mass-asymptotic speed relation in galaxies within the cold dark matter paradigm.
We introduce a novel test of General Relativity in the strong-field regime of a binary black hole coalescence. Combining information coming from Numerical Relativity simulations of coalescing black hole binaries with a Bayesian reconstruction of the
We study a static, spherically symmetric wormhole model whose metric coincides with that of the so-called Ellis wormhole but the material source of gravity consists of a perfect fluid with negative density and a source-free radial electric or magneti
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The paper discusses the optimal conguration of one or more ring lasers to be used for measuring the general relativistic effects of the rotation of the earth, as manifested on the surface of the planet. The analysis is focused on devices having their
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