  In the standard model, the weak scale is the only parameter with mass
dimensions. This means that the standard model itself can not explain the
origin of the weak scale. On the other hand, from the results of recent
accelerator experiments, except for some small corrections, the standard model
has increased the possibility of being an effective theory up to the Planck
scale. From these facts, it is naturally inferred that the weak scale is
determined by some dynamics from the Planck scale. In order to answer this
question, we rely on the multiple point criticality principle as a clue and
consider the classically conformal $\mathbb{Z}_2\times \mathbb{Z}_2$ invariant
two scalar model as a minimal model in which the weak scale is generated
dynamically from the Planck scale. This model contains only two real scalar
fields and does not contain any fermions and gauge fields. In this model, due
to Coleman-Weinberg-like mechanism, one scalar field spontaneously breaks the
$\mathbb{Z}_2$ symmetry with a vacuum expectation value connected with the
cutoff momentum. We investigate this using the 1-loop effective potential,
renormalization group and large N limit. We also investigate whether it is
possible to reproduce the mass term and vacuum expectation value of the Higgs
field by coupling this model with the standard model in the Higgs portal
framework. In this case, the one scalar field that does not break
$\mathbb{Z}_2$ can be a candidate for dark matter, and have a mass of about
several TeV in appropriate parameters. On the other hand, the other scalar
field breaks $\mathbb{Z}_2$ and has a mass of several tens of GeV. These
results can be verified in near future experiments.
