Astronomer Fred Hoyle postulated the existence of an excited state of carbon, called the “Hoyle state,” in order to explain how stars could produce the amount of carbon seen in the universe. Recent theoretical work demonstrated how scientists could calculate the Hoyle state from first principles. The scientists utilized these results to launch further studies of how variations of other fundamental parameters (like the average mass of the lightest two quarks or the fine structure constant) affect the Hoyle state. The results of those studies show that the fine-tuning of carbon production is tied to fundamental quantities.
Life requires carbon. No other element permits the complex chemical bonds like carbon does, and without this chemical complexity life cannot exist. Yet the universe began without the presence of any carbon. A few minutes after the big bang, the universe contained only hydrogen, helium, and trace amounts of lithium. It wasn’t until after stars formed that carbon and oxygen were synthesized in significant quantities. However, when scientists began studying how stars might form these heavier elements, they encountered significant theoretical roadblocks to producing carbon.
In the 1950s, British astronomer Fred Hoyle removed one of those roadblocks by postulating a specific energy level in the carbon nucleus (known as the “Hoyle state”). If the predicted Hoyle state existed, it would explain how stars produced significant amounts of carbon. Scientists experimentally confirmed the energy level shortly after Hoyle’s prediction, but a theoretical understanding of how the energy level arose from fundamental physics eluded discovery for decades.
In May 2011, a team of physicists published such theoretical calculations. Their work laid the foundation for investigating the sensitivity of carbon production’s reliance on fundamental physics quantities. Previous work demonstrated that stars would produce sufficient carbon and oxygen if the Hoyle state varied by as much as 100keV from its actual value.1
Over the past two years, the team of physicists analyzed the production of carbon and oxygen as a function of the mass of the light quarks (the up and down quarks) and the fine structure constant a. Their research found that varying either the quark masses or a by as little as 3 percent from current values produced universes with insufficient carbon and oxygen for life.2 This result shifts the fine-tuning from the Hoyle state (a derived quantity) to the mass of the quarks and the fine structure constant (both fundamental quantities).
Most scientists recognize that the universe appears designed to support life and that many quantities in the universe appear fine-tuned. One response argues that the universe only appears designed rather than actually showing the work of a divine Creator. This argument holds some merit for fine-tuning in derived quantities because sometimes a more fundamental analysis readily explains the “fine-tuned” value. Tying the fine-tuning to fundamental quantities takes the teeth out of this objection and buttresses the argument that the God of the Bible designed this universe in preparation for humanity.
1. H. Schlattl et al., “Sensitivity of the C and O Production on the 3α Rate,” Astrophysics and Space Science 291 (April 2004): 27–56.
2. Evgeny Epelbaum et al., “Viability of Carbon-Based Life as a Function of the Light Quark Mass,” Physical Review Letters 110 (March 15, 2013): 112502.