An approximate model of the spacetime foam

An approximate model of the spacetime foam is offered in which a quantum handle (wormhole) is a 5D wormhole-like solution. Neglecting the linear sizes of the wormhole throat we can introduce a spinor field for an approximate and effective description of the foam. The definition of the spinor field can be made by a dynamic and nondynamic ways. In the first case some field equations axe used and the second case leads to superspace. It is shown that the spacetime with the foam is similar to a dielectric with dipoles and supergravity theories with a nonminimal interaction between spinor and electromagnetic Fields can be considered as an effective model for the spacetime foam.