There is sufficient evidence at present to justify the belief that the universe began to exist without being caused to do so. This evidence includes the Hawking-Penrose singularity theorems that are based on Einstein's General Theory of Relativity, and the recently introduced Quantum Cosmological Models of the early universe. The singularity theorems lead to an explication of the beginning of the universe that involves the notion of a Big Bang singularity, and the Quantum Cosmological Models represent the beginning largely in (...) terms of the notion of a vacuum fluctuation. Theories that represent the universe as infinitely old or as caused to begin are shown to be at odds with or at least unsupported by these and other current cosmological notions. (shrink)

where ds is the space-time interval between two events, a the scale factor representing the radius of the universe at a given time, and do is the line element of a space with constant curvature. The application of this metric to the field equations provides us with the Friedmann’s solutions, which are the heart of big bang cosmology. With the cosmological constant omitted, these solutions read.

Recently, different versions of a cosmological “anthropic principle” have been used to try to explain various features of the universe. This essay, which focuses on some early uses of AP, argues that even modest appeals to it cannot be regarded as genuinely explanatory.