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Recently, it was shown that the quantum effects of the matter, could be
used to determine the conformal degree of freedom of the space-time
metric. So both gravity and quantum are geometrical features. Gravity
determines the causal structure of the space-time, while quantum determines
the scale of the space-time. In this letter, it is shown that it
is possible to use the scalar-tensor framework to build a unified theory in
which both quantum and gravitational effects are present.
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