Cosmology with torsion: An alternative to cosmic inflation

We propose a simple scenario which explains why our Universe appears spatially flat, homogeneous and isotropic. We use the Einstein-Cartan-Kibble-Sciama (ECKS) theory of gravity which naturally extends general relativity to include the spin of matter. The torsion of spacetime generates gravitational repulsion in the early Universe filled with quarks and leptons, preventing the cosmological singularity: the Universe expands from a state of minimum but finite radius. We show that the dynamics of the closed Universe immediately after this state naturally solves the flatness and horizon problems in cosmology because of an extremely small and negative torsion density parameter, $\Omega_S \approx -10^{-69}$. Thus the ECKS gravity provides a compelling alternative to speculative mechanisms of standard cosmic inflation. This scenario also suggests that the contraction of our Universe preceding the bounce at the minimum radius may correspond to the dynamics of matter inside a collapsing black hole existing in another universe, which could explain the origin of the Big Bang.Comment: 8 pages; published versio

Torsion as electromagnetism and spin

We show that it is possible to formulate the classical Einstein-Maxwell-Dirac theory of spinors interacting with the gravitational and electromagnetic fields as the Einstein-Cartan-Kibble-Sciama theory with the Ricci scalar of the traceless torsion, describing gravity, and the torsion trace acting as the electromagnetic potential.Comment: 6 pages; published versio

Connectivity Solutions in Automated Trading

The study analyzes the architecture and deployment of direct market access (DMA) solutions for automated trading of securities.  It provides an overview of automated trading systems including: trading floor architecture, trading environment connectivity, and DMA solutions.  Among a range of factors influencing operational capacities, round-trip latency has been recognized as the key quality differentiator of an automated trading floor.  The study identifies potential opportunity costs due to latency levels as a major driver of technological progress in trading in highly liquid market conditions