EUCLIDEAN QUANTUM WORMHOLES WITH SCALAR FIELDS

We consider the quantum analogs of Euclidean wormholes obtained by Car lini and Mijic (CM), who analytically continued recollapsing closed un iverse models. Using a perfect fluid matter source, we obtain asymptot ically Euclidean (AE) wormholes when the strong energy condition is sa tisfied. Such wormholes are found to be consistent with the Hawking-Pa ge (HP) conjecture for quantum wormholes as solutions of the Wheeler-D eWitt (WDW) equation. By simulating the equation of state of a perfect fluid with a real scalar field, quantum wormholes are also found when the strong energy condition is violated, although generally not AE. T he non-AE solutions are interpreted as excited states of the quantum w ormhole spectrum. Our results give support to the claim of HP that qua ntum wormhole solutions are a fairly general property of the WDW equat ion for various matter sources. Matter sources giving quantum wormhole s could now include those expected in low energy effective string theo ry: a dilaton scalar field with exponential potential. This is unlike the classical case where such matter sources do not allow wormhole sol utions. We finally contrast quantum wormhole solutions with other boun dary conditions of quantum cosmology describing an inflationary earlie r behavior and a resulting large Lorentzian universe phase.