Reasons to Believe

Creation of the First Stars

Scientific evidence for the biblically predicted big bang creation model1 is both overwhelming and compelling. In fact, astronomers have been able to identify a very specific big bang creation model that explains the origin, history, and design of the universe simultaneously. This creation model is the ΛCDM (dark energy dominated cold dark matter) big bang model, otherwise known as the standard cosmological model. The ΛCDM stands for a hot big bang universe dominated primarily by dark energy and secondarily by exotic dark matter where most of the exotic dark matter is in a cold state, that is, where the particles making up the exotic dark matter are moving at low velocities relative to the velocity of light.

In spite of the surpassing success of the hot big bang creation model, and of the ΛCDM model in particular, there still exists a handful of critics who dispute the scientific evidence in favor of these models. Many in this group, which includes both atheists and young-earth creationists, have attempted to refute big bang cosmology by pointing out astronomers so-called failure to detect population III stars, or even to explain the possible existence of, population III stars. In big bang cosmology, population III stars are the first stars to form after the cosmic creation event.

The fireball of the big bang creation event remained at temperatures conducive for nuclear fusion, that is nucleosynthesis, for only about 20 seconds. Such a brief period was not long enough to allow any elements to form from the primordial proton sea (hydrogen gas) other than helium and trace amounts of deuterium (heavy hydrogen), lithium, and possibly miniscule amounts of boron and beryllium. Therefore, the first stars would have been virtually metal-free, composed only of hydrogen (76 percent) and helium (24 percent). (In astronomy any element heavier than helium is considered a metal.)

According to big bang creation models, most (if not all) population III stars would, upon completing their nuclear-burning phase, explode the metals formed in their nuclear furnaces into interstellar space. Thus, the second generation stars (population II stars) would be born with residual metals from the exploded remains of population III stars. After some time, the larger population II stars would explode the remains of their nuclear burning into interstellar space. Therefore, in big bang cosmology as the universe gets older and older it becomes progressively more metal rich. Astronomers observe population II stars to contain from 0.001–2.0 percent metals and the third generation population I stars to contain from 2.0–3.5 percent metals.

In the September/October 2007 issue of Creation Matters (a newsletter published by the young-earth organization Creation Research Society), Steve Miller wrote, “Population III stars are essential for the Big Bang model, yet they have not been observed. Therefore, the Big Bang is not a plausible scientific model.”2. In Refuting Compromise—the most content laden young-earth book attempting to refute old-earth creationism—Jonathon Sarfati claimed, “The total absence of these stars population III stars counts as a falsified prediction of big bang cosmology.”3

Now, for the first time, a team of five Japanese astronomers and physicists, led by Takuya Ohkubo, have calculated a detailed history of what the formation and evolution of zero-metallicity population III stars would look like in a ΛCDM big bang creation model.4 Their analysis demonstrated that two different kinds of population III stars would have formed.

The challenge confronting big bang theorists is how to get primordial gas clouds, without the benefit of metals to form dust, to cool sufficiently so that they can condense to form stars. Heat tends to disperse the gas. For a star to form, gravitational collapse must overcome thermal expansion within a particular gas cloud. Therefore, two circumstances must occur: (1) the mass of the gas must be sufficient to generate a strong gravitational impulse, and (2) some mechanism independent of dust must exist to cool the gas.

Previous calculations of protostar evolution showed that in the zero-metallicity environment the only significant cooling factor is the presence of molecular hydrogen (H2), which will permit nothing other than extremely massive stars to form. However, these calculations stopped at the onset of nuclear fusion of hydrogen within the stars. Ohkubo’s team demonstrated that extremely massive population III stars continued accreting mass long after the commencement of nuclear fusion of hydrogen. They showed that the universe’s very first stars eventually would manifest masses between 300–1,000 times the mass of the Sun. They called these stars population III.1 stars.

Ohkubo’s team further proved that population III.1 stars would radiate copious amounts of ultraviolet radiation and thereby buildup around them clouds of ionized hydrogen (HII regions) gas up to ten thousand light-years in diameter. Such environments facilitated the formation of HD molecules (an HD molecule is the union of a light hydrogen atom with a heavy hydrogen, or deuterium, atom). HD molecules provide much more efficient cooling than H2 molecules. Before the population III.1 stars completed their nuclear burning phase the HD molecules would lead to the formation of metal-free stars between 40–60 times the Sun’s mass. Ohkubo’s team labeled these stars population III.2. Their calculations further established that population III stars between 140–300 times the mass of the Sun would be completely missing from the universe.

Unlike previous attempts to model population III stars, the model developed by Ohkubo’s team perfectly explains the observed metallicity that astronomers see in the most metal-poor population II stars, known as EMP stars.5 It also explains why astronomers have failed to detect population III stars.

The physics of star formation establishes that the greater a star’s mass the faster it completes its nuclear burning. Stars more massive than 40 solar masses will go through their entire evolutionary history—formation, burning, and explosion—in less than a million years. The Sun by comparison will take about ten billion years.

What the rapid evolution of population III stars implies is that once star formation began approximately two hundred million years after the cosmic creation event their production can persist thereafter for just a million years, at most. Thus, in the big bang model all population III stars went extinct more than 13.5 billion years ago. This extinction time means that astronomers must look at least 13.5 billion light-years away to have any hope of observing a population III star. No telescope on Earth or in space has the light gathering power to detect at that distance even the brightest conceivable population III star. However, if money were no object, astronomers could use current technology to build a telescope that would have the power to discover such stars.

Ohkubo’s team solved yet another problem in big bang cosmology. That problem is the rapid origin of supermassive black holes in the nuclei of large galaxies. Supermassive black holes possess masses between a million and several billion times the Sun’s.

As noted, previous models for population III stars missed the fact that such stars could continue to accumulate mass beyond the onset of hydrogen burning. These models had population III stars topping out at a mass 300 times greater than the Sun’s. Such stars are doomed to undergo “pair-instability supernova eruptions” which prevents the production of intermediate mass black holes (black holes with masses between 100–1,000 solar masses). Population III stars in excess of 300 solar masses instead undergo core collapse to form black holes almost as massive as the original stars.

With population III.1 stars ending up as black holes as massive as a thousand times the Sun’s mass, the merger of such black holes could produce the supermassive black holes that astronomers observe in the nuclei of large and giant galaxies everywhere. In particular, the merger of such black holes would explain quasars.

Quasars are supermassive black holes located in the central cores of giant galaxies seen billions of light-years away. At that distance they are existing when the universe was only a few billion years old. At such an epoch the universe was still rich in gas. Supermassive black holes at that time would have been sucking copious amounts of gas into their maws. Just before the gas passes through the black hole’s event horizon about ten percent of its mass gets converted into energy. This very high conversion rate makes quasars extremely bright.

The more we learn about the universe, the smaller and fewer the explanatory gaps in the big bang creation model become. The demonstration by Ohkubo’s team neatly solves and fills in the biggest remaining gaps in the big bang creation model addressed at the beginning of this article. It explains the observed chemical evolution of the universe during its youth and explains why currently existing telescopes cannot detect population III stars. Additionally, it clarifies the origin of supermassive black holes and the observed properties and statistics of quasars.

Though not addressed in their paper, the team’s research adds yet two more fine-tuning parameters to the anthropic principle.6

If the universe’s ratio of population III.1 stars to population III.2 stars were to be slightly altered it would lead to either a complete lack of population I stars or a population that precludes the existence of a planet like Earth. Likewise, if the number density for either the population III.1 or III.2 stars were slightly larger or slightly smaller, it would not be possible for a planet like Earth to exist at the right time in cosmic history to make the support of human life possible. What happens in the first million years after the beginning of star formation in the universe critically determines whether advanced life will be possible some 13.5 billion years later.

The most detailed modeling yet achieved for the earliest star formation in the history of the universe, based on the big bang creation model, matches detailed observations of that history. Miller and Sarfati are wrong. Rather than big bang cosmology being falsified, it has been affirmed. The biblically predicted big bang creation model has passed yet another test.

References:

1. Hugh Ross, The Creator and the Cosmos, 3rd expanded ed. (Colorado Springs: NavPress, 2001): 23–29.

2. Steve Miller, “Population III Stars and the Big Bang Model,” Creation Matters 12, no. 5 (September/October 2007): 3.

3. Jonathon Sarfati, Refuting Compromise (Green Forest, AR: Master Books, 2004), 184.

4. Takuya Ohkubo et al., “Evolution of Very Massive Population III Stars With Mass Accretion From Pre-Main Sequence To Collapse,” Astrophysical Journal 706 (December 1, 2009): 1184–93.

5. Judith G. Cohen et al, “New Extremely Metal-Poor Stars in the Galactic Halo,” Astrophysical Journal 672 (January 1, 2008): 320–41

6. The anthropic principle is the observation that a great many of the universe’s characteristics must be severely constrained in advance of humanity’s arrival in order to make possible the existence of human beings. The principle, in turn, implies anthropic purpose: the amazing cosmic fine-tuning for humanity’s benefit shows that one purpose of the universe is to provide a home for humans.

Subjects: Big Bang, Origin of the Universe, Scientific Evidence for an Old Earth

Dr. Hugh Ross

Reasons to Believe emerged from my passion to research, develop, and proclaim the most powerful new reasons to believe in Christ as Creator, Lord, and Savior and to use those new reasons to reach people for Christ. Read more about Dr. Hugh Ross.