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          | Contents |  
          | In this talk we discuss the    stochastic heat equation on $\mathbb{R}^d$ 
  \[
  \frac {\partial u }{\partial t} =\frac  12 \Delta
u  + u \dot{W},
\]
 where $\dot W$ is a   mean zero Gaussian noise with covariance $
E\left[   \dot{W}_{t,x} \dot{W}_{s,y}\right] =\gamma(s-t) \, \Lambda(x-y)$,
and $\gamma$ and $\Lambda$ are general nonnegative and nonnegative
definite (generalized) functions satisfying some integrability
conditions. The product 
$u \dot{W}$ can be interpreted in both  the Skorohod and
Stratonovich sense.  We will present recent results on the existence and uniqueness of a solution and its H\"older continuity.
Moreover we will establish  Feynman-Kac formulas for the solution  and for  its
moments,  which  allow us to derive   moment  estimates  and intermittency properties. |  |