Borde, Guth, and Vilenkin have shown that all cosmological models in which expansion occurs—including inflationary cosmology,39 multiverses,40 and the oscillating and cosmic egg models—are subject to the BGV theorem.41 Consequently, Vilenkin argues that evidence for a beginning is now almost unavoidable. As he explains, “With the proof now in place, cosmologists can no longer hide behind the possibility of a past-eternal universe. There is no escape; they have to face the problem of a cosmic beginning.”42 Since our universe is expanding and the Borde-Guth-Vilenkin theorem does not depend upon
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