An Accelerating Universe without Lambda: Delta Gravity Using Monte Carlo

A gravitational field model based on two symmetric tensors, g(mu nu) and (g) over tilde (mu nu), is studied, using a Markov Chain Monte Carlo (MCMC) analysis with the most updated catalog of SN-Ia. In this model, new matter fields are added to the original matter fields, motivated by an additional symmetry ((delta) over tilde symmetry). We call them (delta) over tilde matter fields. This theory predicts an accelerating Universe without the need to introduce a cosmological constant Lambda by hand in the equations. We obtained a very good fit to the SN- Ia Data, and with this, we found the two free parameters of the theory called C and L-2. With these values, we have fixed all the degrees of freedom in the model. The last H-0 local value measurement is in tension with the CMB Data from Planck. Based on an absolute magnitude M-V = -19.23 for the SN, Delta Gravity finds H-0 to be 74.47 +/- 1.63 km/(s Mpc). This value is in concordance with the last measurement of the H-0 local value, 73.83 +/- 1.48 km/(s Mpc).