Possible geometrical origin of the accelerated expansion of the Universe

The modified geodetic brane cosmology (MGBC) is tested with observational data. The MGBC is derived from the geodetic brane gravity action corrected by the extrinsic curvature of the braneworld. The density parameter coming from this additional term produces an accelerated expansion of geometrical origin. Subject to the supernovae Ia, observable Hubble parameter, baryon acoustic oscillations and cosmic microwave background probes, the obtained fit provides enough evidence in the sense that the extrinsic curvature effect is able to reproduce the accelerated expansion of the universe without the need for invoking dark energy, exotic matter or a cosmological constant. Moreover, the MGBC is free of the problems present in other braneworld models.

Figure 1

The $1\sigma$ and $2\sigma$ contours in the ${\mathrm{\Omega }}_{\beta }\text{−}{\mathrm{\Omega }}_{dr}$ parameter space. Contours are from the combination of SNIa, $H(z)$, BAO and CMB data. Case I (top panel): A prior on ${\mathrm{\Omega }}_m$ has been considered from the Planck results [35]. Case II (bottom panel): For this case no prior has been assumed on ${\mathrm{\Omega }}_m$. For both cases ${\mathrm{\Omega }}_r={\mathrm{\Omega }}_{\gamma }(1+0.2271N_{\mathrm{eff}})$ has been assumed.

Figure 2

Case III: $1\sigma$ and $2\sigma$ contours in the ${\mathrm{\Omega }}_m\text{−}{\mathrm{\Omega }}_{\beta }$ parameter space. Contours come from the combination of SNIa, $H(z)$, BAO and CMB data.