In part 1 of this article series I described why the Higgs boson is called the “God particle,” and why the sterile neutrino appears much more deserving of the title. In part 2, I reviewed astronomers’ efforts over the past twenty years to discover sterile neutrinos and why these searches, to everyone’s surprise, came up empty. I also clarified how these failures, nevertheless, infused new hope in astronomers that the discovery of sterile neutrinos was at hand. Part 3 explained how that new hope was fulfilled to a substantial degree. This final article in the series discusses the connection between sterile neutrinos and another possible “God particle,” the axion. I will describe where astronomers can quickly collect additional confirming evidence for both sterile neutrinos and axions, and conclude with a summary of some of the faith-strengthening theological advances we can expect from these discoveries, both current and emerging.

In many respects, we humans are the dominant species on Earth. There are nearly seven billion of us and each of us weighs an average of over fifty kilograms (110 pounds) each. However, compared to ants our total biomass is less than a tenth. Compared to prokaryotes (bacteria and archaea) our total biomass is less than a hundredth of a percent. As it is with Earth’s life, so it is with the universe’s particles. It is the lightest known particles, axions and neutrinos—not protons, neutrons, and electrons—that make up most of the universe’s mass. As I will describe shortly, axions and neutrinos share another thing in common with prokaryotes: they play especially crucial roles in making possible the existence of humans and civilization.

In part 3 of this series, I described the work of astronomer Dmitry Prokhorov and physicist Joseph Silk; they demonstrate how astronomers were looking in the wrong place in their quest to discover sterile neutrinos.¹ They then point out that the discovery of sterile neutrinos may have already been made serendipitously in the detection of excess radiation in a certain iron spectral line seen at a particular x-ray wavelength emanating from the center of the Milky Way Galaxy. Additionally, Prokhorov and Silk point out how certain observations of dwarf galaxies provide confirming evidence of sterile neutrinos’ existence. They also mention how some straightforward follow-up observations of the iron x-ray spectral line emanating from the galactic center would either prove or disprove their identification of the excess radiation as evidence for sterile neutrinos.

There are other ways Prokhorov and Silk’s identification could be confirmed. If the measured excess indeed results from inflatons decaying into sterile neutrinos, as they claim, then discovering the inflatons would be a huge boost to their assertion. As I mentioned in part 3, the axion is the leading inflaton particle candidate.

The Axion Connection

Obviously, Silk and Prokhorov’s conclusion would be substantially strengthened if scientists could prove that axions make up the bulk, or at least a large fraction, of the universe’s exotic matter. However, until very recently all efforts to detect axions had failed. This failure was not at all surprising to physicists and astronomers given that the best theoretical work on axions had proven that the mass of an axion could not be greater than several millielectronvolts (meV).

In June 2009, four Spanish astronomers published a paper in which they point out that if axions exist, they will escape freely from white dwarfs (burnt out stars—see figure 1). Given a high abundance of axions in white dwarf stars, their escape would increase the cooling rate of white dwarfs substantially. The four astronomers then demonstrated that “the inclusion of the axion emissivity in the evolutionary models of white dwarfs noticeably improves the agreement between the theoretical calculations and the observational white dwarf luminosity function.”² They also showed that the improved agreement rules out a mass for the axion any larger than 10 meV.

Figure 1: A Typical White Dwarf Star Compared to the Sun
A white dwarf is a burnt out star. When a star exhausts its nuclear fuel, it suffers severe gravitational collapse. A typical white dwarf possesses about a third to two-thirds the mass of the Sun but is not much bigger than the size of Earth. Though burnt out, a white dwarf takes many billions of years to cool down. White dwarfs today manifest surface temperatures about four to seven times hotter than the Sun’s.
Image credit for the Sun image: STEREO Project, NASA

In March 2010, two of those Spanish astronomers collaborated with two Argentinean astronomers to add a second piece of evidence for the existence of axions.³ This team explained how the slow cooling process of white dwarf stars translates into an increase of certain variable white dwarfs’ pulsation periods. Since the existence of axions would increase the rate at which white dwarfs cool, astronomers can use measurements of the pulsation periods’ rate of change to prove or disprove the existence of axions. In their paper the team presented values for the rate of change in the pulsation period for the white dwarf G117-B15A. They demonstrated that these values are compatible with the existence of axions at the mass level suggested by the white dwarf luminosity function established in the June 2009 paper.

Further proof of the existence of axions, as the Spanish and Argentinean astronomers explain, is now straightforward. Measuring the pulsation period drifts of not just one but dozens, and hopefully hundreds, of variable white dwarfs would seal the case for the existence of axions. But it could do much more than that. It could also establish the abundance of axions in the universe, the mass of the axion particle, shed light on the abundance level and properties of sterile neutrinos, and yield insight on the constituent components of the universe’s exotic matter.

Many More Potential Confirmations

There are other ways astronomers and physicists could detect sterile neutrinos and potentially determine some of their physical properties. For example, a significant abundance of sterile neutrinos would distort both the temperature and polarization maps of the cosmic microwave background radiation (CMBR, radiation left over from the cosmic creation event).⁴ While the WMAP satellite lacked the sensitivity to detect the sterile neutrino signal, the Planck satellite currently collecting data on the CMBR may have a good chance.⁵

Other currently feasible measurements and expressed hopes are the use of galaxy cluster maps, supernova observations, galaxy redshift surveys, substructure gravitational lensing in galaxy clusters, pulsar velocities, and measurements of the primordial abundances of deuterium, helium, and lithium to determine or at least constrain the properties of sterile neutrinos.⁶ Very recently, several physics research teams have proposed five different laboratory experiments that, for relatively modest outlays of money and time, could possibly detect and measure sterile neutrinos.⁷ The now operational CERN Large Hadron Collider can also make a significant contribution.⁸ What is reasonably certain is that someone or some team involved in all this research on sterile neutrinos will win the Nobel Prize.

Saving Time and Money

Say what you will about former president Bill Clinton, he was a masterful election campaigner. In his first run for the presidency all his campaign offices were plastered with memos to his staff and volunteers. The memo message: It’s the economy, stupid.

For scientists today the same message applies. What is the most economic way to gain the research results we all want?

Especially encouraging to the scientific community and to taxpayers is that the efforts to discover and determine the characteristics of sterile neutrinos and axions need not cost billions of dollars and millions of man-hours. While accelerators like CERN’s multi-billion-dollar Large Hadron Collider will certainly make their unique contributions to our understanding of these particles, relatively cheap astronomical observations involving only dozens of scientist man-hours are now known to be adequate not only to discover these particles but also to determine several of their properties. Economic astronomical pathways even exist for discovering and investigating Higgs bosons as was demonstrated by a recent paper published by two Romanian astrophysicists.⁹

The Theological Prize

From a theological perspective, the bigger trophy will be determining the degree to which the characteristics (especially the mass, average momentum, abundance, and location) of sterile neutrinos must be fine-tuned to explain why life, especially human life, is possible in the universe. Just to name a few examples, if it were not for the extraordinary, that is, supernatural fine-tuning of the characteristics, abundance, and locations of sterile neutrinos:

• star formation would begin at the wrong time and at the wrong level;
• the universe would possess the wrong abundance of baryons;
• supernovae would scatter the wrong abundance of heavy elements into the interstellar and intergalactic media;
• exotic dark matter halos would have the wrong shape and uniformity; and
• the universe would manifest the wrong number of dwarf and sub-dwarf galaxies for physical intelligent life to be possible at any time or place in the cosmos.

Sterile neutrinos would bolster the biblically predicted hot big bang creation model¹⁰ by resolving eight anomalies in the standard cosmology and particle physics creation model simultaneously. Even more than that, they would also significantly augment the evidence for the supernatural, super-intelligent design of the universe to make possible the existence of physical life, especially human beings and their global, high-technology civilization.

Axions, as well, contribute to the evidence for the design of the universe for humanity’s specific benefit. Like sterile neutrinos, the characteristic features, abundance, and geographical placement of axions must be fine-tuned. Thanks to the recent observational and theoretical discoveries concerning sterile neutrinos and axions, scientists now possess much more complete and much better integrated models of cosmic and particle creation. Such completeness and integration adds yet more proof for the biblical creation model and the attributes of the biblical Creator.