  Recently much controversy has been shed on BICEP 2 experiments for the
concerning this validity or not and a possible set of new experiments to detect
primordial inflation and gravitational waves. Since gravitational waves imply
the existence of primordial magnetic fields in this context, C Bonvin, R Durrer
and R Marteens [Phys Rev Lett (2014)] have tried to associate the presence of
primordial magnetic fields to BICEP 2 by making use of CMB tensor modes. Here
we show that by considering torsion dilatonic lagrangean one obtains
cosmological magnetic fields of the order of $B\sim{10^{-10}G}$ which may seed
galactic dynamos. Actually this new result came out of a mistake of a recent
paper published by myself in JCAP (2014). These results are more in accordance
with Bamba results [JCAP (2014)] in the context of teleparallel theory of
gravity with Einstein's distant parallelism and torsion. These results also
support Einstein-Cartan sort of theories of gravity from well-known recent
data. Another example which supports the use of modified gravities with torsion
to investigate magnetogenesis is the alternative exampleof using axions with
transmutation into torsion to obtain cosmic magnetic seed bound of
$10^{-12}G$.This coincides with the lower bound obtained by Barrow et al [Phys
Rev D (2012)] in the interval of $10^{-20}G$ to $10^{-12}G$ in Friedmann
universes.
