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We refine and extend a programme initiated by one of the current authors[Science 276 (1997) 88; Phys. Rev. D56 (1997) 7578] advocating the use of theclassical energy conditions of general relativity in a cosmological setting toplace very general bounds on various cosmological parameters. We show how theenergy conditions can be used to bound the Hubble parameter H(z), Omegaparameter Omega(z), density rho(z), distance d(z), and lookback time T(z) as(relatively) simple functions of the redshift z, present-epoch Hubble parameterH_0, and present-epoch Omega parameter Omega_0. We compare these results withrelated observations in the literature, and confront the bounds with the recentsupernova data.

Cosmodynamics: Energy conditions, Hubble bounds, density bounds, time and distance bounds