The Origin of the Large Scale Structure is one of the key issue in Cosmology.
A plausible assumption is that structures grow via gravitational amplification
and collapse of density fluctuations that are small at early times.
The growth history of cosmological fluctuations is a fundamental observable
which helps in hunting for evidences of new physics, currently missing from our picture
of the universe, but potentially crucial to explain its past, present and future history.
I'll show how we investigated if the gradual growth of structures observed
over a period of nearly 9 billion years can be used to discriminate between
different gravitational models. I'll also discuss how the measurement of the cosmic
growth rate provides an alternative independent probe to understand the origin of
the accelerated expansion of the universe.