Martin Rees

Martin Rees (b. 1942) is a British cosmologist and astrophysicist, Astronomer Royal since 1995, and former President of the Royal Society (2005–2010). Educated at Cambridge, where he succeeded Fred Hoyle as Plumian Professor of Astronomy and Experimental Philosophy, Rees has contributed to research on black holes, galaxy formation, quasars, and the cosmic microwave background. His popular writings — notably Just Six Numbers (1999), Our Cosmic Habitat (2001), and Our Final Hour (2003) — have made him a prominent public communicator of cosmology. In Just Six Numbers, Rees argues that six dimensionless constants finely tune the universe for the emergence of complexity and life; he canvasses three explanations (brute fact, design, or a multiverse) and inclines toward the multiverse hypothesis as a naturalistic account of apparent fine-tuning. This position has placed his work at the center of debates between theistic natural theologians (e.g., John Polkinghorne, Robin Collins) who view fine-tuning as evidence for design, and naturalists who appeal to anthropic and multiverse reasoning. Rees describes himself as a non-believer who nonetheless attends Anglican services for cultural reasons, and he has resisted New Atheist polemics, favoring a respectful science–religion coexistence. Critics such as Paul Davies have questioned whether the multiverse genuinely explains fine-tuning or merely relocates the problem. Rees has been honored with the Order of Merit and a life peerage (Baron Rees of Ludlow).