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In the standard picture, the inflationary universe is in a supercooled statewhich ends with a short time, large scale reheating period, after which theuniverse goes into a radiation dominated stage. An alternative is proposed herein which the radiation energy density smoothly decreases all during aninflation-like stage and with no discontinuity enters the subsequent radiationdominated stage. The scale factor is calculated from standard Friedmanncosmology in the presence of both radiation and vacuum energy density. A largeclass of solutions confirm the above identified regime of non-reheatinginflation-like behavior for observationally consistent expansion factors andnot too large a drop in the radiation energy density. One dynamical realizationof such inflation without reheating is from warm inflation type scenarios.However the solutions found here are properties of the Einstein equations withgenerality beyond slow-roll inflation scenarios. The solutions also can becontinuously interpolated from the non-reheating type behavior to the standardsupercooled limit of exponential expansion, thus giving all intermediateinflation-like behavior between these two extremes. The temperature of theuniverse and the expansion factor are calculated for various cases.Implications for baryongenesis are discussed. This non-reheating,inflation-like regime also appears to have some natural features for a universethat is between nearly flat and open.Comment: 26 pages, Latex, 2 figures, In press Physical Review

Interpolating the stage of exponential expansion in the early universe: Possible alternative with no reheating