Evidence from the Size of the Universe

We’ve already discussed the vastness of the universe earlier in this chapter. We noted that the most distant galaxies are over 10 billion light years away, indicating that the light left these galaxies over 10 billion years ago in order to reach us today. The straightforward interpretation of these data is that the universe must be at least 10 billion years old.

While some people have argued that perhaps these galaxies aren’t really that far away, all of the methods used to measure distance agree that galaxies are billions, not thousands, of light years away. Others have argued that perhaps the light moved much faster when it first left these galaxies, so that it could reach us in much less time than 10 billion years. But this idea conflicts with other data that we have. As described in Chapter 3, ample evidence supports the idea that physical processes such as quantum mechanics and electromagnetism function the same way in distant galaxies as they do on earth. Those physical processes depend on the speed of light and would look very different if the speed of light had changed. Instead, they look the same in distant galaxies as they do on earth, indicating that the speed of light has been constant over the history of the universe.

Evidence from the Moon and Planets

Studies of the Moon and planets also give evidence for great age. Geologists can use some of the same methods to measure the age of rocks on the Moon, Venus, and Mars as they use on Earth. That’s because the asteroid collisions, volcanoes, and erosion they observe on Earth also occur on the Moon and planets. Photos taken by spacecraft while orbiting Mars show channels and gullies on the planet’s surface. Similar channels on Earth are usually made by flowing water. Yet there is no liquid water on the surface of Mars right now.

What does this have to do with age? It is evidence that Mars was much different in the past than it is today. The atmosphere used to be much thicker and warmer, similar to Earth’s, but now it is much colder and thinner. This dramatic change in planet-wide climate took millions or billions of years. Thus the rocks testify that the planet Mars must be at least this old.

Evidence from the Orbits of Asteroids

The orbits of asteroids also show evidence of a long history. When an asteroid is discovered, its path through the sky shows its orbit around the Sun. Once astronomers know the orbit of an asteroid they can calculate its orbit in the past and into the future to see whether it will hit the earth. By calculating the orbits backward, astronomers have found several asteroids that converged at the same location several million years ago. Apparently two larger asteroids collided at this spot and shattered into the smaller asteroids we see today. If God had created asteroids just a few thousand years ago, why would he have put them in orbits that suggest a collision several million years ago? The evidence clearly points to a long history for asteroids.

Evidence from Meteorites

Radiometric dating is used to study rocks on Earth as well as rocks from elsewhere in the solar system. Studies have been done on the rocks that astronauts brought back from the Moon and on asteroids that have fallen to Earth. As with Earth rocks, scientists use multiple radioactive isotopes to cross-check age measurements. At least three different isotopes have been used to measure the age of Moon rocks, and at least five different radioactive isotopes have been used to measure the age of meteorites. The results all agree: the oldest Moon rocks and asteroids are 4.6 billion years old. This is our best measure of the age of the solar system as a whole. The universe itself must be at least this old.

Evidence from Star Clusters

Another important measure of age in the universe comes from star clusters. Because all stars in a star cluster form in the same nebula at about the same time, they all have about the same “birthday.” But they don’t all have the same lifespan. High-mass stars burn bright and fast like a “flash in the pan,” while low-mass stars burn slowly and steadily. Consider how this will look in a star cluster. A cluster starts with many stars with the same birthday but of all different masses. Over time the high-mass stars die off first, leaving behind the low-mass stars. This means that if many high-mass stars are present, the cluster must be young because they haven’t burned out yet. If most of the stars are low-mass, the cluster must be old. Careful studies of star clusters show that some clusters are younger and some are older, with the oldest ones having an age of about 12 billion years.

Multiple Lines of Evidence

The most distant galaxies, the planets and asteroids of our own solar system, and the oldest star clusters all are several billion years old. Astronomers have many different methods for measuring the age of various objects, and they all support ages of billions of years, not thousands. Even if the assumptions of one or two methods were faulty, it is highly unlikely that all of the methods would be affected. Like the geologists in the 1700s, astronomers today have found multiple lines of evidence against a young earth and young universe.

It may seem as though we are once again describing a conflict between science and theology. Scientific results that indicate great age do conflict with the Young-Earth Interpretation of Genesis 1 discussed in chapter 5. But remember that in chapters 5 and 6 we presented many other interpretations of Genesis 1; several of these are not in conflict with the great age found in the book of nature. In chapter 6 we also explained why we believe that the best biblical scholarship, quite independent of modern science, indicates that Genesis 1 was never meant to convey scientific information to the original audience. Its intent for the first listeners, and for us, is to teach the who and why of creation, not the how and when. Taken in this context, there is no conflict between Genesis 1 and the astronomical evidence for great age.

For background on related topics (like the reliability of historical science and interpretations of Genesis), see previous excerpts from this series.

Excerpt from Chapter 7 of Origins: Christian Perspectives on Creation, Evolution, and Intelligent Design (Grand Rapids, MI: Faith Alive Christian Resources), 2011. Reprinted with permission. To purchase a copy of the book or e-book, call 1-800-333-8300 or visit www.faithaliveresources.org.

Want a free copy of Origins?  For a limited time, donations of $50 or more will receive a  copy of the book! Plus, from now through April, your gift will be doubled thanks to a matching grant from a generous donor. You can learn more here.

What does it mean for humanity to be created “from the dust of the ground?”

In many ancient Mesopotamian creation stories, human beings were depicted as deriving from some physical part of the gods. Often this was the result of conflict: humans arose from the blood, flesh or tears of gods slain by other gods. Humans created in this fashion were supposed to serve the gods by performing menial work that the gods had tired of doing themselves. The lot of humanity, then, was one of violence and servitude.

In the Israelite creation stories reflected in Genesis 1 and 2, however, humans are made from the ordinary material of creation: “dust.” Humans are made of earth-stuff, not god-stuff.

At first glance, it may seem that this lowers the status of the human creature. We might ask the question raised by Eliphaz in the book of Job:

Can a mortal be more righteous than God?
Can even a strong man be more pure than his Maker?
If God places no trust in his servants,
if he charges his angels with error,
how much more those who live in houses of clay,
whose foundations are in the dust, who are crushed more readily than a moth! (Job 4:17-19)

Indeed, our humble origins ought to remind us of the fragility of our lives. As the Psalmist says,

You turn people back to dust, saying, “Return to dust, you mortals.”
A thousand years in your sight
are like a day that has just gone by,
or like a watch in the night.
Yet you sweep people away in the sleep of death—
they are like the new grass of the morning:
In the morning it springs up new,
but by evening it is dry and withered.

The elements of which our bodies are made are ordinary and abundant. Science tells us that approximately ninety-three per cent of the mass in a living human body is comprised of elements first formed through nuclear fusion in the hearts of stars. Through almost unimaginably vast and ancient cycles of stellar formation and supernova explosions, this “stardust” of elements has been spread throughout the universe. It is as though God scattered the stars across space and time to seed the universe for life, including your life and mine. And we are thereby inseparably connected to each other, to the air we breathe, to the ground we tread, to all the creatures that fill the skies and crawl upon the earth and teem in the seas, to the depths of all the heavens. We are not transcendent of creation. We are creatures.

Yet we are creatures into which God breathed the “breath of life.” We are stardust and more than stardust. We are not reducible to our constituent chemicals. A “man” or a “woman” is not just a gooey sack of water, carbon and trace elements. Hydrogen, oxygen and carbon are not aware of their own existence. These elements cannot reason or pray or love or write poems. Conjunctions of these elements cannot carry any persistent identity across time. They do not exercise will or intentionality or agency. They are not “selves.”

Most of the cells in a human body are in constant flux: aging, dividing, dying, being replaced. The surface layer of human skin is renewed completely about every two weeks. An adult’s skeleton is entirely remade over approximately ten year periods. It may be that only the neurons of the cerebral cortex and a few other types of cells persist throughout the lifetime of a human body. And eventually, it all does return to “dust.”

Yet we think of ourselves as persisting over time, as comprising an “identity,” a “self.” Perhaps the cerebral cortex provides the stable biological platform for identity and selfhood, but something new emerges from the chemical-electrical soup, new patterns of organization, a different level of causation. We can even make choices that reshape ourselves, both physically and psychologically. The very wiring of our brains changes when we make conscious choices. Mind is both shaped by matter and supervenes on matter.

Materialists who wish to collapse all of human identity into brain chemistry overstep the bounds of “science.” A fundamental principle of scientific practice is testability: is it possible to demonstrate empirically whether a proposition is false ? As Saint Augustine observed many centuries ago, the fact that I acknowledge I could be “wrong” about something means that I am a “self” who is capable of making real choices about things that are in fact true or false. “Si fallor, sum” Augustine said – if I can doubt, if I can be wrong, then I must exist. One who is a true materialist “all the way down” cannot test his or her materialism. There is no possibility of “being” right or wrong, indeed no possibility of “being” – there is nothing but chemistry.

Spiritualists who wish to degrade matter in favor of the soul or spirit likewise are not expressing a Christian anthropology. Indeed, one of the first heresies that encountered the early Christian church was Gnosticism. A core belief of Gnosticism was that matter, including the human body, was essentially evil. Salvation for the Gnostics involved the soul’s escape from the prison of embodiment and materiality. The Gnostics treated the body either with disdain – engaging in extreme ascetic practices – or with antinomian abandon – engaging in extreme sexual license. Either way, their practices were rooted in the belief that matter and the body were unimportant. It’s easy to see how this view continually creeps into both our popular culture and our Church cultures.

Christian theology asserts that humans are spiritual creatures, a unity of body and spirit or “soul,” integrated, not reducible downwards to mere matter or upwards to mere spirit. Perhaps there is no better way to bring these themes together than with a Psalm — here is Eugene Peterson’s paraphrase of Psalm 139 in The Message:

God, investigate my life; get all the facts firsthand.
I’m an open book to you;
even from a distance, you know what I’m thinking.
You know when I leave and when I get back;
I’m never out of your sight.
You know everything I’m going to say
before I start the first sentence.
I look behind me and you’re there,
then up ahead and you’re there, too—
your reassuring presence, coming and going.
This is too much, too wonderful—
I can’t take it all in!

Is there any place I can go to avoid your Spirit?
to be out of your sight?
If I climb to the sky, you’re there!
If I go underground, you’re there!
If I flew on morning’s wings
to the far western horizon,
You’d find me in a minute—
you’re already there waiting!
Then I said to myself, “Oh, he even sees me in the dark!
At night I’m immersed in the light!”
It’s a fact: darkness isn’t dark to you;
night and day, darkness and light, they’re all the same to you.

Oh yes, you shaped me first inside, then out;
you formed me in my mother’s womb.
I thank you, High God—you’re breathtaking!
Body and soul, I am marvelously made!
I worship in adoration—what a creation!
You know me inside and out,
you know every bone in my body;
You know exactly how I was made, bit by bit,
how I was sculpted from nothing into something.
Like an open book, you watched me grow from conception to birth;
all the stages of my life were spread out before you,
The days of my life all prepared
before I’d even lived one day.

Belief in God in an Age of Science

Introducing John Polkinghorne

An Englishman of Cornish descent, John Polkinghorne was born in 1930 in the coastal town of Weston-super-Mare, southwest of Bristol in North Somerset. Although his parents had three children, an older sister died in infancy and his older brother, who served in the RAF Coastal Command during World War II, died when his plane was lost over the North Atlantic on a stormy night in 1942. Effectively an only child from that point on, his family nurtured him in their Christian faith, leading him to say a few years ago, “I cannot recall a time when I was not in some real way a member of the worshipping and believing community of the Church.”  (From Physicist to Priest, p. 7)

At the same time, his gift for mathematics did not go unnoticed, resulting in several years of study at Trinity College, Cambridge (where Isaac Newton had lived and worked in the seventeenth century). As an undergraduate, Polkinghorne studied applied math rather than pure math, a typical choice for someone interested in physics. There, he formed a close friendship with a classmate, Michael Atiyah, who would be best man at his marriage in 1955 to another mathematics student, the late Ruth (Martin) Polkinghorne. Later knighted, Sir Michael was President of the Royal Society in the early 1990s, the same period when Polkinghorne was president of Queen’s College, Cambridge.

​Sir Michael Atiyah (Source)

Polkinghorne was particularly inspired by the course in quantum physics taught by Paul Dirac, whom he has described as “undoubtedly the greatest British theoretical physicist of the twentieth century,” an opinion with which it is hard to disagree. For Polkinghorne, Dirac’s lectures were simply unforgettable: “so profound was the material, and so closely structured was the argument, that one was carried along enthralled by the experience.” (From Physicist to Priest, p. 26)

Paul Dirac (Source)

Remaining at Cambridge for graduate study, Polkinghorne worked under the Pakistani physicist, Abdus Salam, who later became the first Islamic scientist to win the Nobel Prize, which he shared with Americans Sheldon Glashow and Steven Weinberg for contributions to unifying the electromagnetic force and the weak nuclear force. Then he did postdoctoral work at Caltech with Murray Gell-Mann, another future Nobel laureate for his work on quark theory, and attended the famous lectures by yet another future Nobel laureate, the late Richard Feynman.

After Caltech, Polkinghorne taught briefly at Edinburgh before returning to Cambridge, where he was soon elected to a new professorship in mathematical physics. Quantum mechanics (QM) is his specialty; his writings on both QM and its interaction with theological ideas are numerous. His book, The Quantum World, has sold more than 100,000 copies, and when Oxford University Press wanted a book on this topic for their highly successful series, “A Very Short Introduction,” it was Polkinghorne who wrote it. His former students include Nobel laureate Brian Josephson, “the most precociously brilliant undergraduate that I ever taught,” and Martin Rees, who was until recently President of the Royal Society.

Although Polkinghorne has never won a Nobel Prize, in 1974 he was elected Fellow of the Royal Society, the highest honor in British science. Three years later, at the top of his scientific career at age 46, he astonished his colleagues by announcing a decision to pursue ordination as an Anglican priest; two years later, he resigned his chair at Cambridge to enter seminary. Partly, he felt played out. As a former physics student myself, I do not find his diagnosis hard to accept: “In mathematically based subjects you do not get better as you get older. Somehow one needs mental agility more than accumulated experience, and it becomes progressively harder for an old dog to learn new tricks. It is unlikely that most people do their best work before they are 25, but most do before they are 45.” Or, to put it more succinctly, “I simply felt that I had done my little bit for particle theory and the time had come to do something else.” (From Physicist to Priest, p. 71)

Nevertheless, he also felt a genuine call to the ministry, for “Christianity has always been central to my life” and ‘becoming a minister of word and sacrament would be a privileged vocation that held out the possibility of deep satisfaction.” (From Physicist to Priest, p. 73) After seminary, Polkinghorne served as a parish priest for many years and later as canon theologian of Liverpool Cathedral. He was knighted in 1997—although, as an ordained minister, he declines to use the title, “Sir John Polkinghorne”—and was awarded the Templeton Prize in 2002. It has been altogether a life well lived for the kingdom of God.

Looking Ahead

I’ll return in about two weeks with a summary of Polkinghorne’s basic attitudes toward science and religion, which (in his view) have a “cousinly” relationship. In the meantime, readers are invited to read Zeeya Merali’s essay, “The Priest-Physicist Who Would Marry Science to Religion,” from the March 2011 issue of Discover magazine, and “An interview with John Polkinghorne,” by philosopher Paul Fitzgerald.

References

John Polkinghorne, From Physicist to Priest: An Autobiography (2008).

Transitional Fossils

Some time ago, the Discovery Institute’s Casey Luskin commented on the human origins exhibit at the Smithsonian Institution, suggesting that palaeoanthropologists use evolutionary theory to describe the progression of the human lineage even when they don’t have transitional fossils with which to work. He writes:

What's ironic, however, is that if you ask the question How Do We Know Humans Evolved? the answer you’re given is, “Fossils like the ones shown in our Human Fossils Gallery provide evidence that modern humans evolved from earlier humans.” So whether you find fossils or you don’t, that’s evidence for evolution.

Indeed, it has become an article of faith for those espousing both the young earth creation (hereafter YEC) model and many who hold to the intelligent design model that transitional fossils do not exist and therefore evolution has not taken place. Support for this position usually entails attacking the weak areas of the fossil record, where burial processes have left us little with which to work, or the creation of straw men arguments in which transitional fossils are defined in such a way that none could ever be found. Often this centers on the concept of “missing link,” a term that is habitually used in the popular press and young earth creation and intelligent design literature when referring to fossil remains but which has little to no meaning for biologists or palaeontologists. As Ahlberg and Clack (Ahlberg and Clack 2006) write:

But the concept has become freighted with unfounded notions of evolutionary ‘progress’ and with a mistaken emphasis on the single intermediate fossil as the key to understanding evolutionary transitions. Much of the importance of transitional fossils actually lies in how they resemble and differ from their nearest neighbours in the phylogenetic tree, and in the picture of change that emerges from this pattern.

Contrary to common misconceptions, the fossil record does not record one single lineage for any family of organisms but rather a series of branches, with many related species coexisting synchronously. Darwin hypothesized that the evolutionary record reflected this bushiness and drew such a diagram in his journal. At the time, though, he had little in the way of fossil evidence to back up this position. Much has changed since his day.

An analogy for understanding this “bushiness” was best described by Prothero and Buell (Prothero and Buell 2007). They suggest that the reader consider his or her own genealogy. You and your siblings are the direct descendents of your parents and, while you are similar to them, each of you has different characteristics not shared with them as well as characteristics that you do share. Your parents have siblings as well (your aunts and uncles), and your grandparents are their last common ancestors. These siblings have their own children (your cousins), who have different and similar traits relative to their parents. They are broadly recognizable as being related to you (“oh, I see you have Aunt Edna’s nose”) but three or four generations out, they will become less and less so. These are the “nearest neighbours” that Ahlberg and Clack describe. In this analogy, each of these cousins represents a transitional form from what was (your grandparents) to what will be down the road.

For example, no one would confuse a frog with a salamander but if you trace the fossil record of each back in time, eventually you encounter a fossil, Gerobatrachus hottoni which was recently discovered (Anderson et al. 2008) that is best described as a “frogamander,” having the basal characteristics of both frogs and salamanders. Had we seen such an animal at the time, it is likely we would not have found it remarkable because it would have resembled the species around it. One lineage eventually diverged into frogs, salamanders and other amphibians. Most (just like Darwin proposed in his tree diagram with the little hatch marks at the tip of many branches) went extinct.

Taxonomy and the Beginnings of Human Origins

All life is classified based on a system devised by Carolus Linneaus in 1735 in his remarkable work Systema Naturae. This system gives all recognized species an individual place based on a system of hierarchy. The study of classification is known as taxonomy. A taxonomic ranking for humans would be this:

When a fossil is excavated, the first thing that the palaeontologist does is make a taxonomic assessment of where it fits in a sequence of known fossils. Traits that are shared with other like species or genera are referred to as primitive traits. Examples of this in humans are five fingers and the presence of three arm bones. We share this with all mammals. Traits that are new or are not shared with other like species are referred to as derived traits. Examples of this in humans are the skeletal changes in the pelvis and the foot to allow for walking upright. We do not share these with any other primates.

Transitional fossils in the human fossil record are distinguished at both the genus and species level. This group includes the extinct genera Ardipithecus and Australopithecus and the current genus Homo. All species except Homo sapiens are extinct. Much of the recent study of early humans focuses on the transition from Ardipithecus (‘Ardi’) to Australopithecus (‘Lucy’ and similar fossils) and from Australopithecus to Homo, the genus that led eventually to us. While each of the australopithecine species identified in the fossil record has derived characteristics that separate them from their ancestors and from each other, only one led to the genus Homo.

In future posts, I will describe the evidence for human evolution and why this evidence is compelling. It suggests that we have had a long, varied history filled with great leaps of change, crushing defeat, and eventual expansion into all areas of the globe.

Notes

Ahlberg, P. & J. Clack (2006) A firm step from water to land. Nature, 440.

Anderson, J. S., R. R. Reisz, D. Scott, N. B. Frobisch & S. S. Sumida (2008) A stem batrachian from the Early Permian of Texas and the origin of frogs and salamanders. Nature, 453, 515-518.

Prothero, D. & C. Buell. 2007. Evolution: What the fossils say and why it matters. Columbia Univ Pr.

It’s true that physics sounds scary to many people, and it can indeed be a difficult topic to learn. Yet I’ve always loved physics (my degrees are in physics rather than astronomy), because of the way that mathematical equations can describe and predict so much of what we see in the world around us. One reason I got into astrophysics is because the universe contains so many bizarre situations that we can’t reproduce on earth, like ultracold, or extremely high density, or extremely high magnetic fields. It’s a fun challenge to figure out which physical process will be the most important when the situation is so dissimilar to everyday experience. But if the word “physics” makes you shrink in distaste or fear, don’t worry. For the rest of this article, we’ll focus on a more friendly topic: astronomy.

In the last decade or two, our knowledge of the universe has grown dramatically as many new telescopes and spacecraft have come online. In this essay, I’ve selected some of my favorite recent astronomy photographs to share with you. As a professional astronomer and a Christian, I feel God has called me to share these wonders with the Church. Many times, these new discoveries are presented without any mention of God, and sometimes in a context of overt atheism. I want to share these things with you in a Christian context, with God as their creator.

The Milky Way

Have you ever seen the Milky Way? If you live in a rural area, you may have seen it many times. If not, it may have been a dramatic surprise when you first saw it while camping or traveling. On a clear night out in the country, the sky is strewn with brilliant stars—many more stars than you can see under city lights.The faintest stars form a creamy, smoky band from horizon to horizon. Our galaxy contains billions of stars, and thousands of those stars are visible to the naked eye. The stars appear in a band across the sky because we are viewing our galaxy edge-on, like looking at the edge of a dinner plate.

When David looked up at the night sky over Israel thousands of years ago, he may have seen the Milky Way, or a comet, or simply the brilliance of the full moon. Whatever the sky looked like that night, it inspired him to sing:

The heavens declare the glory of God; the skies proclaim the work of his hands. Day after day they pour forth speech; night after night they reveal knowledge. They have no speech, they use no words; no sound is heard from them. Yet their voice goes out into all the earth, their words to the ends of the world. (Ps. 19:1-4a)

The heavens are displaying the glory of God for all people to hear, proclaiming their message to people of every language, tribe, and nation. Just about anyone who looks up at the night sky feels a sense of wonder. Yet as Christians, we feel more than a vague sense of awe; we know the Creator of the heavens personally, as our own loving Father.

The heavens declare more than God’s glory. The universe is God’s revelation of himself to us, and teaches us about his character. As the Belgic Confession says about “The Means by Which We Know God,”

We know him by two means: First, by the creation, preservation, and government of the universe, since that universe is before our eyes like a beautiful book in which all creatures, great and small, are as letters to make us ponder the invisible things of God: his eternal power and his divinity, as the apostle Paul says in Romans 1:20. Second, he makes himself known to us more openly by his holy and divine Word, as much as we need in this life, for his glory and for the salvation of his own. (Article 2)

The natural world teaches us about God’s glory, power, divinity, faithfulness, extravagance, immensity, love, and other attributes. God’s special revelation in scripture is our primary place to learn of God’s character (Ps. 19 goes on to talk about special revelation in vs. 7), but the natural world can bring the message to our senses in a powerful way beyond mere words on a page. The Holy Spirit can use the natural world to get the message past our hardened or weary hearts. Nature illustrates these attributes in ways that enlarge our imaginations to appreciate afresh the glory of God.

The Sun

The Solar Dynamics Observatory was launched into space in 2010, the latest of several spacecraft to photograph the sun in detail. In Figure 2, the upper photo shows the face of the sun with a sprinkling of sunspots. The sun is powered by nuclear fusion reactions deep in its core which heat the hydrogen and helium gas till it glows. A sunspot is a place on the sun’s surface where the gasses are a bit cooler than the surrounding area, so that it glows less brightly and appears dark.

The lower photo in Figure 2 was taken the same day, but in X-ray light. X-rays are invisible to our eyes, but you have experienced them at the dentist’s office. There, the X-rays are produced by a machine, travel through the mouth, and are detected by film to reveal an image of your teeth. In this image, X-rays are produced by the sun, travel to the Solar Dynamics Observatory, and are detected by a camera to show an image of the sun. In X-rays, the sunspots are the brightest part of the image, not the faintest. If you look at the sunspot on the left edge, you can see bands of particles rising out of the sunspot in a looping path above the sun’s surface and falling back down on it. As the particles follow lines of magnetic field, they emit X-rays. The loops you see are not small—they are about the size of planet Earth! Because of modern spacecraft, telescopes, and cameras, we can see so much more in the heavens than what is visible to the naked eye. Thus, we are seeing more of what the heavens have to declare about God. In Psalm 19, David goes on to describe the sun:

In the heavens God has pitched a tent for the sun. It is like a bridegroom coming out of his chamber, like a champion rejoicing to run his course. It rises at one end of the heavens and makes its circuit to the other; nothing is deprived of its warmth. (vs. 4b-6)

If David had lived today, maybe he would have written about other properties of the sun, like the power of God as seen in nuclear reactions and looping magnetic fields. As it is, he makes two important points. One is the universal warmth of the sun, by which God provides for all life on earth. The other is the faithful path of the sun, day after day, unchanging year after year. In the book of Jeremiah, God promises his people that he will not break his covenant with them, any more than he would break his covenant with day and night and the fixed laws of heaven and earth (33:19-26). The sun is a persistent reminder, woven into our lives, of God’s faithfulness to his promises.

The Denisovans, an extinct hominid group that interbred with modern humans, made the news again lately with the publication of a more detailed study of their genome. One of the many interesting findings was that the Denisovans share the same chromosome 2 fusion that modern humans have. In this post, I review what we know about the origins of human chromosome 2, and then discuss the new Denisovan findings and their implications.

The origins of human chromosome 2: a brief review

Though I have discussed the evidence for a fusion event leading to human chromosome 2 before, perhaps a brief review of the evidence is in order. The human genome is made up of 23 pairs of chromosomes (for a total of 46 chromosomes). This makes us something of an oddity among living great apes, all the rest of whom have 24 pairs of chromosomes (for a total of 48). Given that there are many independent lines of evidence that support the conclusion that we share a common ancestor with other great apes, this poses something of a conundrum: how is it that our species arrived at this specific chromosome number? If we were to represent this “problem” on a phylogeny, or tree of relatedness, it would look something like this (not to scale):

Our closest living relatives, chimpanzees and bonobos, both have 48 chromosomes, as do all other great apes such as gorillas and orangutans. This pattern has one of two explanations, one of which is much more likely than the other. Either the common ancestor to these species had 48 chromosomes, and there was an event that reduced that number to 46 specifically on the lineage leading to humans (option A), or the common ancestor species had 46 chromosomes, and there were independent, repeated events that increased chromosome number in all other great ape species (option B). We can compare these options by placing the required event(s) on the phylogeny (again, not to scale):

It should be obvious that the option that requires the fewest events is the more likely one – in this case option A with an event that reduces chromosome number in the lineage leading to humans. The other option, that of repeated, independent events to increase chromosome number, remains a formal, but unlikely, possibility. Events that reduce chromosome number are not frequent occurrences, so Option A is more likely than Option B.

We can also find further support for Option A, because it predicts a specific type of event, namely one that reduces chromosome number. Since loss of a large amount of chromosomal material is almost always detrimental, we need an event that reduces chromosome number without losing information. One way for this to happen is for two chromosomes to fuse together and become one. Initially, this event would produce an individual with 47 chromosomes, where two different chromosomes get stuck together. Contrary to what is often assumed, this individual would be fertile and able to interbreed with the others in his or her population (who continue to have 48 chromosomes). In a small population, over time, two relatives who both have one copy of the fusion chromosome may mate and produce some progeny with two copies of the fused chromosome, or the first individuals with 46 chromosomes. Since either a 48-pair set or a 46-pair set is preferable for ease of cell division, this population will either eventually get rid of the fusion variant (the most likely outcome), or by chance will switch over completely to the “new” form, with everyone bearing 46 chromosome pairs. While not overly likely, this type of event is not especially rare in mammals, and we have observed this sort of thing happening within recorded human history in other species. Some mammalian species even maintain distinct populations in the wild with differing chromosome numbers due to fusions, and these populations retain the ability to interbreed.

Further evidence for a fusion event in the lineage leading to modern humans comes from comparing synteny, or gene locations and orders on chromosomes within modern great apes – an issue we have discussed here before. In brief, what we see in human chromosome 2 is exactly what we would predict for a fusion event. When compared to other great apes, we see the genes on human chromosome 2 match up, in order, with two smaller ape chromosomes. We also see that sequences used at the tips of chromosomes are present at the proposed fusion site, and that human chromosome 2 has not one but two sites for the cell cytoskeleton to attach to for cell division – but that one of the sites is mutated and not functional, though it lines up precisely with the location of this site on the appropriate ape chromosome. Together, this evidence consistently supports both common ancestry for humans and great apes, and specifically that the difference we see in our chromosome numbers arose due to a single fusion event. I briefly discussed this evidence in my last post where I describe how I teach some of this material and the compelling impact it has on students exploring the evolution question for the first time.

Enter the Denisovans

With that as background, we are now prepared to appreciate a new finding that comes from genomics work done on the Denisovan hominids, an archaic species that is more closely related to Neanderthals than to us, but that nonetheless interbred with some anatomically modern humans as they migrated out of Africa and populated the globe. (For those not familiar with the Denisovans, or the evidence for our interbreeding with them, both Darrel Falk and I have written on this previously, here and here). Recently, a more detailed understanding of the Denisovan genome was published, and nested in the new information is the discovery that the Denisovans share the 46 chromosome set with the same fusion that we have. This strongly supports the hypothesis that the fusion event predates the separation of our species. If we were to represent this on a phylogeny, we can now place this event with more accuracy than before (as before, the phylogeny is not to scale):

Despite this new information, one obvious question remains. Did the Neanderthals also have the 46-pair set? From looking at the phylogeny above, we can see that the most likely answer is that they did, since the fact that the Denisovans had it strongly implies that the last common ancestor of humans and Neanderthals / Denisovans had it as well, and the Neanderthal-Denisovan split comes later. While the Denisovan DNA samples are of high enough quality to make this assessment, we do not yet have Neanderthal DNA of high enough quality to do the same analysis with current methods (though one additional feature of the new work on the Denisovan genome is developing more sensitive DNA sequencing techniques that may resolve this question in the future).

In other words, this fusion seems to be an ancient one, predating our species by several hundred thousand years. Present estimates of the last common ancestor between humans and Neanderthals / Denisovans range at about 800,000 years ago.

Implications for understanding our “becoming human”

The main implication from this work is that it places the fusion event well before the advent of our species. I’ve often chatted informally with Christians about evolution, and at times some have thought that this fusion event was what “started” our species, or made our species unable to interbreed with other groups. Some have even suggested that perhaps the fusion event was what produced the first human (i.e. Adam).

Note that thinking this way suggests a misunderstanding of how chromosome fusions occur and what effect they have on their hosts. A fusion does not precipitate a speciation event, but rather the individual with the fusion remains a part of his or her population, and able to interbreed, even if with reduced fertility. Also, there is no necessary biological effect or change that the fusion produces on the appearance of the organism. These misunderstandings aside, however,what this new evidence shows is that this fusion event took place long before modern humans arose at around 200,000 years ago. Indeed, the 800,000 years ago date for the last human - Denisovan common ancestor means that this is the most recent date possible for the fusion. While it is an interesting piece of our evolutionary history, it doesn’t seem to have much to do with how we came to acquire the traits that set us apart from, and ultimately outcompete, other similar species.

(Click Image for Full Resolution)

For more, be sure to read our FAQs How are the ages of the Earth and universe calculated? and What scientific evidence do we have about the first humans?, as well as our recent infographic How Do We Know the Earth is Old?.

Author's Note from Joy Walters

As I mentioned in my first post, I grew up skeptical of the whole idea of evolution. One contributor to my disbelief was the lengthy timescale for the “tree of life” that was presented with the theory. I would hear, for example, that dinosaurs lived hundreds of millions of years ago, but there was no explanation of why this was true; it was just given as a fact. No one explained the methods of dating, and so I thought biologists simply estimated the ages of species to fit their preconceived notions of how long it would take for one species to emerge from another. It also seemed like the ages were periodically revised and extended farther back in time, and I figured scientists needed to manipulate numbers to make evolution plausible. This, in my mind, made the theory both unbelievable and dismissible.

Once I learned about the techniques used to date fossils, I realized that my first impressions were wrong; the ancient ages of species are scientific determinations rather than scholarly conjectures. However, I have found in recent conversations that Christians remain skeptical of old ages and the evolutionary time scale. For this reason, I wanted the videocast to address the process of fossil dating (what the methods are and why they are accurate) while focusing on cases where hominid fossils were discovered and dated using these very methods. My hope is that Believers would be informed about the evidence for human evolution and its scientific grounding.

It has been widely reported that the moniker “God particle” was not its originator’s first choice. Still, Leon Lederman, director emeritus of Fermilab and Nobel laureate for neutrino research, did accept the nickname “God particle” because the particle is “so central to the state of physics today, so crucial to our final understanding of the structure of matter, yet so elusive.” “God particle” was quickly accepted by the press and general public because it seemed an appropriate title for a particle theorized to give mass to all elementary matter particles and the force carrying W and Z bosons. Serving this mass-giving function since near the beginning of the universe, a Higgs field (more fundamental than the actual Higgs boson ) must necessarily exist everywhere in the universe and be unchanging. With an omnipresent and immutable field, analogies between the Higgs boson and God naturally developed within the press and the public—“God particle” became deeply rooted. Relatedly, the Higgs boson become an excellent source for theological analogies. (See for example this article.)

Nevertheless, as physicists seek to emphasize, neither the Higgs boson particle nor its field have religious properties. Thus, elementary particle physicists are not fond of the “God particle” appellation. In the opinion of Oliver Buchmueller, of CERN’s CMS group, calling the Higgs boson the “God particle is completely inappropriate. It’s not doing justice to the Higgs and what we think its role in the universe is. It has nothing to do with God“. As Pippa Wells, another CERN scientist expressed, “Calling [it] the God particle … confuses people about what we are trying to do at CERN”. (Source: Reuters)

One alternate name for the Higgs particle that is used within the physics community is the “BEH” particle. “BEH” stands for Brout–Englert–Higgs, three of the six authors of 1964 papers that first proposed a mechanism for giving mass to elementary particles. In addition to Peter Higgs, the five other authors are Robert Brout and Francois Englert, and Tom Kibble, C.R. Hagen, and Gerald Guralnik. The process for giving mass to particles is thus sometimes referred to not just as the Higgs mechanism, but as the Brout–Englert–Higgs–Hagen–Guralnik–Kibble (BEHHGK) mechanism. (Saying all six names a couple of times makes it obvious why we most often only call it the Higgs.)

But issues of naming aside, what is the Higgs and why is it so elusive? According to the Standard Model, the particles that compose matter (the quarks and leptons) are in a category called spin-1/2 particles. The force carrying particles (the photon, the W's, the Z, and the gluons) are spin-1 particles. What the physicists above proposed was the existence of a type of spinless, or spin-0 particle. Not only does the Higgs boson form its own class of particles, it also gives mass to itself and to all the other particles that have mass: to all of the leptons and quarks, and to the W's and Z bosons, but not photons or gluons. This set of relationships is shown in the image below, indicated by the lines connecting the Higgs to these other particles. There are no lines directly connecting the Higgs boson to photons and gluons because the Higgs boson does not interact with these force carrying particles and, thus, photons and gluons remain massless.

But the story of the Higgs particle actually begins with the associated Higgs field, an invisible field (something like a generalization of an electric field) that has a non-zero, constant value everywhere throughout the universe. This Higgs field continuously interacts with all matter particles and the W and Z force carrying particles. Matter and massive force particles are slowed down as they move through the Higgs field, just as are balls rolling through thick mud. The Higgs field is sometimes described as a “cosmic molasses”. Different particles interact with the Higgs field to varying degrees—those interacting more, are slowed down more, those interacting less are slowed down less. Slowing down more equates to acquiring more mass. If not for the Higgs field, all particles would be massless, zipping through the universe at the speed of light. The universe would be without structure—no galaxies, no plants, no life. Without the Higgs field, not even atoms could have formed.

It was theoretically possible for elementary particles to have mass without needing to acquire it through interaction with a Higgs-like field. However, as the standard model of elementary particles developed in the 1950’s and 1960’s, elementary particle theorists realized that if particles had their own innate mass, rather than acquiring it, many beautiful symmetries of particle interaction equations would be broken. To keep the beauty and symmetry in the theory was the essential reason the BEHHGK mechanism was developed, which immediately led to the prediction of Higgs bosons.

When there is enough external energy in a given volume, the Higgs field also produces Higgs bosons. But the Higgs bosons are very unstable and quickly decay. This is the process that enabled the discovery of the Higgs boson at CERN. At CERN, protons are accelerated to high energies via electric fields and directed in circular paths via magnetic fields. The protons then collide and release large amounts of energy. When sufficient energy is released in a collision, the Higgs field can use this energy to produce Higgs bosons. The Higgs bosons quickly decay leaving evidence of their existence through particular combinations of leftover particles that they have decayed into. Among those predicted by the mathematics of the Standard model are the muons and electrons identified by the CERN experimenters. The image at the top shows the identities and paths of particles produced in one of the CERN proton-proton collisions whose results fit with what would be expected from the decay of a Higgs boson.

For a proton-proton collision at the CERN LHC, the above diagrams show both the dominant modes for creation of a Higgs with a mass around 125 GeV, and the two dominant decay channels (modes). The creation mechanism (shown schematically in the left half of each diagram above) involves virtual gluons, the carriers of the strong nuclear force (represented by squiggly purple lines) from the protons. The gluons fuse into a virtual top quark loop (medium blue triangle), which then emits a Higgs boson (squiggly yellow line). The top quark couples more strongly to the Higgs than any of the five other quarks, so the top quark contributes the dominant loop.

The Higgs boson then dominantly decays into either (i) 2 gamma ray photons (the squiggly green lines) via another intermediate virtual top quark loop or a virtual W gauge particle loop (dark blue triangle), or (ii) two Z0 gauge particles (squiggly dark blue lines), which each then decay into a lepton (specifically an electron or a muon)/anti-lepton pair (light blue lines).

The likely discovery of the Higgs boson, and its implied existence of the associated Higgs field, is an amazing success for CERN. Past research and experience at Fermilab and by elementary particle physicists throughout the world also contributed to the discovery. The Higgs boson was the remaining particle in the Standard Model of Particle Physics to be found. With it, the Standard Model is in some sense complete. (Nevertheless, many questions about the Standard Model still remain—many inspired once again by beauty and symmetry. In particular, several numeric values associated with particle masses and interactions could only be experimentally measured, as with the Higgs, and not predicted from the Standard Model.)

With the apparent success of these experiments and seeming confirmation that the physical universe is, indeed, reflected by the complex and beautiful mathematics of the Standard Model, the international physics community is eager to keep delving deeper into the structure of creation. In addition to trying to verify that the 125 GeV particle is, indeed, the Higgs spinless particle and not some more exotic, new particle, CERN physicists are simultaneously seeking to discover an entire new class of particles, resulting from a theorized symmetry called supersymmetry. Discovery of the associated particles, if they exist, will likely take a few more years. For these discoveries we can only wait in anticipation.

Updated July 12, 2012.

Judging from the flurry of headlines over the past week, one might be tempted to think that proof positive of God’s existence (or lack thereof) had just appeared out of a 27-km-tunnel buried beneath the Swiss-French border. This frenzy of news headlines and blog titles hailed the recent news that CERN’s Large Hadron Collider has discovered a brand new particle of a mass of 125-126 GeV, which is assumed to be the Higgs boson, or the so-called “God particle.” The discovery of the Higgs boson would certainly be a breakthrough for particle physics and cosmology, but would such a finding also radically redefine theology’s understanding of God or challenge the existence of such a deity? Is there actually any theological or religious significance in Higgs physics at all?

The short answer is “no,” which becomes apparent when one considers the widely-reported story of how it got named. In 1993, Nobel Laureate physicist Leon Lederman, along with science writer Dick Teresi, wrote a book detailing the history of particle physics starting with Pre-Socratic Greek philosophy Democritus and culminating with the hunt for the Higgs boson. Until this latest discovery, the Higgs boson was the elusive final missing piece of the puzzle known as the Standard Model—a collection of the fundamental particles that constitute our universe and the complex and mathematically-sophisticated relationships between them. Considering how incredibly difficult finding the Higgs boson was proving to be, Lederman wanted to name the book after that “goddamn particle,” according to some of his collaborators. His editor, however, would not allow it and so the name was shortened to “The God Particle: If the Universe Is the Answer, What is the Question?” And thus ‘the God particle’ was born, carrying with it more than enough social baggage for such a miniscule particle.

Particle physicist Dr. Zosia Krusberg (at right) is visiting assistant professor of physics and astronomy at Vassar College and thinks “the term ‘god particle’ is unfortunate. The Higgs boson is no more (or less) divine or spiritually significant than any other elementary particle within the standard model of particle physics.” It may be fundamental to explaining one of the most basic characteristics of the universe—namely the existence of matter and mass in addition to energy—but “it is no more (or less) important than any other physics principle underlying the Standard Model.”

Last week’s discovery was monumental in that it may have finally provided experimental evidence for the Higgs Mechanism and defined the specific energy of the resulting Higgs boson, but even this “breakthrough” for particle physics leaves many scientific questions unresolved. Finding the Higgs boson completes the Standard Model, but it does not do away with many other questions and shortcomings of the current state of particle physics, such as the constituent particles of dark matter, a quantum theory of gravity, and other “mathematically subtle problems.” Not to mention that there is still significant work to be done to determine the exact nature of this newly-found particle. According to Dr. Krusberg, this particle might behave just as the Standard Model predicts or it could instead be “a Higgs-like particle that will serve as a gateway into explorations of physics beyond the Standard Model." Krusberg continued, “And I guarantee that it is this latter scenario that most of us are hoping for: physicists love nothing more than discovering the shortcomings of their theories, since this is the first step toward more fundamental theories with even more predictive power!”

No, finding the Higgs boson does not answer all the questions of particle physics, much less lend insight into the existence (or not) of God. For that reason, Dr. Krusberg (like most physicists) bemoans the term ‘God particle’ and insists, “There really is nothing either literally or metaphorically god-like about the Higgs boson.” Indeed, one writer for the British journal The Guardian reached such a point of frustration about the name that he ran a competition for alternatives. The winner was “the champagne flute boson,” ostensibly because the bottom of a champagne bottle is an excellent and oft-used demonstration of the energy potential of the Higgs Mechanism. Or then again, perhaps it is simply because physicists thought that finally finding this shy particle would call for some of the bubbly.

On the other hand, some science writers and scientists can appreciate the ‘educational benefits’ of such a mysterious and controversial name because it attracts the attention of the general public and puts a relatable face on an extremely esoteric physics concept. Krusberg herself admits that “People are naturally drawn to the mysterious and the controversial, providing educators with great teaching opportunities.” But she worries about the larger social implications involved in “mixing the vernacular of physics and spirituality,” not least because such uncritical mixing can lead the non-scientific community to draw conclusions about the authority and reach of science that are not justified.

Understanding that the Higgs boson is not the literal stuff of God and that it does not prove or disprove God’s existence (as the name seems to suggest) extinguishes the fire under any sort of religious outcry. But this does not mean that its discovery is irrelevant to the discussion of science and faith, nor to the Christian community as a whole. As Dr. Krusberg remarks, “The recent discovery of [this] new boson at the LHC perfectly embodies the scientific process at its best (and thereby illustrates to the public why and how science works).” Scientific exploration of nature is not a fool-proof endeavor; healthy skepticism and accountability to a wide community of other researchers are absolutely critical to its success. But such evidence of the power and finesse of well-executed science as we saw last week is a testament to our ability to explore and understand the ‘how’ of the universe. God has equipped humanity with the desire, the intellectual abilities, and the collective will to recognize and explore the cosmic order and beauty of his creation. God has made our home knowable, and has given us the tools and capacities by which to know it.

At left, Cern researchers present their findings to a few hundred of their colleagues in Melbourne, Australia. Image © 2012 CERN

It is valuable, then, for the Christian community to understand and appreciate how science works, in part to recognize that there are many instances in which science and the church work in tandem in order to better understand and better serve the world. But I think there is something else we can draw from the story of the Higgs boson, too. The nickname ‘the God particle’ has touched nerves in religious communities because it implies that science has the ability to prove or disprove divine existence by physical means. Even though the physics community is by no means claiming insight into the divine, it is sometimes assumed by the religious community that scientists view their work as chipping away at God’s existence when they begin to understand something that was previously unknown, or known only “by faith” in esoteric theories and models.

And yet, regardless of motives or metaphysical interpretations, perhaps physicists' search for the Higgs boson is in fact an apt picture of our own search for God. How many times have we stared up at the starry ceiling in times of crisis and prayed fervently for some kind of sign from God to assure us of his presence? And how many times has that much-desired evidence appeared only in retrospect, when we look back to see God’s hand faithfully and elegantly working in ways inscrutable at the time? It took a community of physicists to discern the presence of the Higgs boson. But even so, they could only do so after the fact from the cascade of particle decays it sparked; they could not observe the particle itself directly. In a similar way, though we often do not see the working of God directly, “in the moment,” we still trust in his presence and providence, often depending on friends, family and the community of the church to help us see his hand in hindsight.

So while the discovery of the Higgs boson does not itself explain God, we rejoice at the subtle yet striking new insight we have into God’s creative genius via the Higgs boson and at the way God gives evidence of his faithfulness in the ordered creation itself. Perhaps, however, the greatest insight we can glean from this breakthrough is an analogy for the way God calls us to seek him and find him together, in the community of those who follow his son.

Tomorrow, Baylor University physicist Gerald Cleaver answers the question, "What is the Higgs boson?"

The astronomy community is particularly interested in this event because exoplanets throughout the Milky Way galaxy regularly transit their parent stars in just the same way. This local example will allow astronomers to test and refine techniques used to determine the composition of these exoplanets' atmospheres, providing insight into whether these distant planets could possibly harbor life.

As Venus begins to cross in front of the disk of the Sun, Venus's atmosphere will refract the Sun's light, illuminating the backlit portion of the planet's atmosphere. Telescopes on the ground and in orbit will be trained on this thin arc of atmosphere lit up by the Sun. Astronomers will use spectrometers to break the light up into its constituent colors, from which they can determine the chemical composition of our over-heated sister planet's atmosphere. Once perfected, this same technique can be used to examine the atmospheres of planets far beyond our own solar system, offering us one of our best clues as to the habitability of these distant worlds.

Not only is this process of discovery exciting for natural science, but it has profound theological ramifications as well. Surely a God capable of orchestrating both the majestic swirls of a spiral galaxy and the intricate language of DNA could bring forth life where and when He chooses, but only now are we on the verge of being able to answer the age-old question: “Did God confine His creative life-giving actions to our own planet, or does His abundant fertility extent far beyond our limited experience?”

In 1882, William Harkness, the Director of the U.S. Naval Observatory, was one of two astronomers to determine from the transit of Venus the distance from Earth to the Sun. Just as previous viewers could never have imagined calibrating the scale of the solar system from such an event, Harkness could not predict its importance in 2004 and 2012 (the most recent Venus transits). As we look to the future, we can hardly imagine what new frontiers the next Venus transit of 2117 will find us exploring.

The image above shows Venus on the eastern limb of the Sun during the 2004 transit. As described in Tucker's essay, the faint ring around the planet comes from the scattering of light through its atmosphere, which allows some sunlight to show around the edge of the otherwise dark planetary disk. The faint glow on the disk is an effect of the TRACE telescope through which the image was captured. For more on the historical significance of the transits of Venus (including the voyage of Captain James Cook), see this article from NASA, which also includes links to several live webcasts of today's transit.

I ask the question, “Why is the universe so special?” Now scientists don’t like things to be special; we like things to be general, and our natural anticipation would have been that the universe is just a common or garden specimen of what a universe might be like.

But we’ve come to understand a lot about the history of the universe. We know that our universe started 13.7 billion years ago, and it started extremely simple, just an almost uniformly expanding ball of energy, about the simplest physical system you could possibly think about. But a world that started so simple has of course become rich and complex. With you and me, in fact, the most remarkable and complex consequences are its history, at least of which we are aware. The human brain is far and away the most complicated physical system we have ever encountered anywhere in our exploration of the universe.

That fact itself might suggest that something has been going on in cosmic history rather than just one thing after another. But we’ve also come to understand many of the processes by which this rich fruitfulness has come to birth. As we’ve come to understand these, we’ve come to see that though these processes are of course evolving processes, they took long periods of time – the universe was 10 billion years old before any form of life appeared in it, at least as far as we know anyway – and life of our complexity only appeared yesterday.

Nevertheless, the universe is pregnant with life, pregnant with the possibility of life, essentially from the beginning onwards. By which I mean the given laws of nature had to take a very specific, very finely tuned form, if the universe was to have so fruitful a history.

That’s a very remarkable discovery, and let me give you some examples of why we believe that. If you’re going to have a fruitful universe, one of the first things you have to get right is that you have to have the right stars in the universe. The stars are going to have a very important role to play. First of all, you must have some stars that are going to be very long lived, live for billions of years, steadily burning, steadily producing energy which will enable the development of life on one of the encircling planets. We understand what makes stars burn in that sort of way very well, and it depends on a delicate balance between the strength of gravity and the strength of electromagnetism. Electromagnetism is the force that holds matter together. The seats on which you are sitting are held together by electromagnetism and in fact you are held together by electromagnetism.

If you alter that balance a little bit in one direction the stars will begin to burn intensely, furiously, just pouring out energy and they will only live a few million years rather than a few billion years. If you move it a little bit in the other direction they will burn so slowly they will be brown stars and they will not produce enough energy to fuel the development of life. So you have to have a very delicate finely tuned balance between the strength of gravity and the strength of electromagnetic forces in a fruitful universe.

Remember, science takes the laws of nature, takes the given strengths of gravity, the given strength of electromagnetism, uses that to explain processes in the world, how things happen, but it doesn’t explain where those laws of nature come from. They are just brute facts as far as science is concerned.

And the stars have another absolutely indispensible role to play. The stars are the place where the heavier elements essential for life are made in the interior nuclear furnaces. There are many elements that are necessary for life, of which carbon is perhaps the most essential. Carbon is the basis of the long chain molecules, which are the biochemical basis of life. The early universe only makes the simplest elements; it makes hydrogen and helium and it makes no carbon at all. Carbon only begins to be made when the universe, which started uniform, begins to condense and become lumpy and grainy with stars and galaxies. As the stars condense they heat up, nuclear processes begin again in their interiors. And it’s those nuclear processes in the stars that make carbon and the heavier elements. Every atom of carbon in your body was once inside a star. We are people of stardust made in the ashes of dead stars.

And that’s a very beautiful process that takes place in that sort of way. And one of the great triumphs of astrophysics and the second half of the 20th century was to unravel that process. One of the people who did some of the most important work on that was a senior colleague of mine in Cambridge called Fred Hoyle. And they were trying to figure out how to make carbon. They got helium, and if you can make three helium nuclei stick together that will produce carbon, but when you have something as small as a nucleus it is impossible to get three to stick together at one time, they’re just too small.

Ok, so let’s do it step by step. Stick two together gives you berylium. Helium 4 gives you beryllium-8, hope it stays around for a bit, another helium comes along, attaches itself, and bingo, you’ve got carbon-12. That’s the obvious thing to think about but it doesn’t work in the obvious way, and the reason it doesn’t work in the obvious way is that beryllium-8 is terribly unstable. It doesn’t oblige you by staying around long enough to catch that third helium, at least in an ordinary, straightforward way.

But Fred realized that it would be just possible for this to happen if there was a very large enhancement effect, in the trade we call it resonance, occurring in carbon at just the right energy, it has to be the right energy, which would enable that attachment process to catch that third helium much much more quickly that you might have thought, in fact so quickly that some of them would get caught before the beryllium-8 disappeared. It was a very good idea, and he must have felt pretty pleased with himself and he went off to just check in the nuclear data tables of this particular resonance’s energy levels, and it wasn’t in the tables, but he knew it must be there, he’s carbon based life like you and me.

So he rang up some friends in the States, a father and son team who were good experimentalists and he said, “Look, you missed something. There’s a resonance and energy level in carbon that you haven’t spotted, and I’ll tell you exactly where to look for it. I know exactly where this energy has got to be. You go look for it.” And they said, “No, no, we don’t want to do that, we have more interesting things to do.” But Fred was very determined and he bullied them into looking for it and they found it.

Now that’s a wonderful achievement, to predict an energy level in carbon on the basis of how it might have been made in the stars is a fantastic scientific achievement. But it’s more than that. Fred had a lifetime conviction of atheism, realized of course that if the laws of physics had been just a little bit different that resonance wouldn’t have been there, and the possibility of carbon-based life is too significant for it just to be a happy accident in his view, so he says in a Yorkshire accent that is beyond my power to imitate, he said that the universe is a put-up job. Fred didn’t like the word God, and so he said some Intelligent, capital “I” Intelligence, must have monkied with the laws of nature to make carbon production possible. What that could possibly be I don’t know, but the more sensible thing to say is that creation is ordained, that the laws of nature would be such, as to enable the fruitfulness of carbon-based life.

We’ll come back to evaluating that possibility in a minute, but before we do, let me give you two other examples of how specific, how special, our universe has to be for us to be able to be here today to think about. We live in a universe that is immensely big, beyond our powers to imagine really. There are a hundred thousand million stars in our galaxy in the Milky Way, of which our sun is just a common or garden specimen, and there are about a hundred thousand million galaxies in the observable universe, of which our Milky Way is a pretty common or garden specimen. So we live in a world that is unimaginably vast, and sometimes we might feel upset by that and think, “What could be the significance of us who are simply inhabitants of a speck of cosmic dust, as you might say, in this vast, vast universe?”

Nevertheless, if all those stars were not there, we would not be here to be upset at the thought of them. Because there is a direct connection between how big a universe is and how long it lasts, and a universe that is significantly smaller than our universe would not have been able to last the 14 billion years, which is the necessary time to produce beings of our complexity. So that’s another condition of the world that has to be right for human beings, or something like human beings, to be a possibility.

One final example, which is the finest tuning of all: quantum theory suggests that there should be an energy attached to space itself. In quantum theory the vacuum, so called empty space, is not just a void. There are things called vacuum fluctuations which occur in a continual sort of seething mass of things coming into being and going out of being all the time. So while there is nothing there that doesn’t mean there is nothing happening. That may sound strange and paradoxical but believe me that’s what quantum theory implies. And of course these happenings, these fluctuations, generate a certain amount of energy, we call it “zero point energy”, and that energy is spread out over the whole of space. So we expect there to be energy associated with space.

And just recently the astronomers have discovered something called dark energy which is driving the expansion of the universe, which is just such an energy associated with space. Well that’s very good, you might say. However, when we estimate, just from thinking about quantum theory, how much energy there should be in space it turns out to be a fantastically large amount, and when we see the amount of energy there actually is per volume in space, it turns out to be very, very small in relation to that expected size. In fact, it turns out to be smaller by a factor of 10^-120. That means by a factor of 1 over 1 followed by 120 zeros. You don’t have to be a great mathematician to see that’s a fantastically small number. So some fantastic cancellation has taken place to turn that big number into the tiny number that we actually observe, and if it hadn’t taken place we wouldn’t be here to observe it because significantly higher energy would simply have blown the whole show apart too fast for anything interesting to happen. That’s the finest tuning that we know in the universe: one part in 10¹²⁰.

So we live in a world that is very remarkably finely tuned, and we have to consider that. And all scientists would agree about what I have been telling you; this is non-contentious. Where the contention comes in is what we might make of that, what is the further significance of it.

In the conclusion to Dr. Polkinghorne’s lecture, he looks at two explanations for the "fine-tuning" principle -- the multiverse theory and the existence of a divine intelligence -- and explains why natural theology alone is not sufficient to make the case for a God who interacts and cares for his creation. To make the case for theism, he argues, we need revelation, God's self-disclosure. This is manifest in various ways, including that which we experience personally, including ethics and aesthetics.

Many posts on this Forum have suggested that the cosmological narrative in Genesis 1 is best read as being primarily about God’s identity and agency, rather than about the physical make-up or material history of the natural world. Similarly, we demonstrate our highest regard for Genesis 2’s account of the creation of Eve—the second fully human being—by looking to its meaning in terms of spiritual and interpersonal relationships, rather than genetic ones. While the specific “how” of our being made into the image of God will probably always remain a mystery, the Bible and creeds are clear on the “why” of our creation: we were made to worship the Lord, and be in relation with Him and each other. That intimate, conscious and deeply symbolic knowledge of our maker and fellow human beings is a profound difference that sets us apart from the other creatures.

I have frequently argued that poets are often the most clear on some of the important issues of our faith, including this one. Today we feature a work by Robert Siegel, who identifies the imagination as the faculty by which we recognize and name those spiritual relationships. As he says, “It's the imagination, hence language and art, that establishes the connections”; it is the imagination that allows us to conceive of and name the links between ourselves and creation, ourselves and each other, ourselves and the Creator God.

Though we often focus on Adam’s naming of the animals, and then even of Eve, Siegel helps us remember that it was in hearing his own name that Adam’s whole humanity came into being: he experienced the richness of being called by God to bear His likeness, but also of being called to by one that was profoundly “like him.” Put another way, we are speakers, but also equally hearers. May we, too, be awakened to ourselves and our image-bearing identity by a still, soft voice saying our name. May we, too, in gratitude and delight, call upon the name of the one, Jesus, who is both our God and our fellow man.

“Adam’s Dream”

by Robert Siegel

The Imagination may be compared to Adam's dream:
he awoke and found it truth. --Keats

He saw the garden spreading past the trees
he'd been warned to avoid (yet keep a special eye on).
He'd learned by scents, transported by the breeze,
myriads of roses and how, by hand, the scion

of one to graft on another--and what was edible:
whole families of legumes, grasses, roots,
melons, peaches, apples, pears. Incredible,
the variety of tastes just from the fruits!

But it wasn't enough. Even the breathing animals
with friendly grunt or sigh, silken warm side,
and large affectionate eye were not able
to speak. When he named them, none replied:

His words fell dead on the air--though he said
them everywhere, walking or running to each place:
to the mountain, which echoed back the sounds he made,
or the still pool, returning his own gaze.

But no one answered him until one night in a dream
he woke and heard a soft voice speak his name.

“Adam’s Dream” first appeared in issue 3 of Stonework, the literary journal of Houghton College. © 2001 Robert Siegel

Robert Siegel is the author of nine books of poetry and fiction, most recently A Pentecost of Finches: New and Selected Poems. He has received prizes and awards from Poetry, Prairie Schooner, The Transatlantic Review, the Ingram Merrill Foundation, and the National Endowment for the Arts, and his poems have appeared in numerous journals and anthologies. His fiction includes Alpha Centauri and the Whalesong trilogy, which received the Golden Archer and Matson awards. With degrees from Wheaton, Johns Hopkins, and Harvard, Siegel has taught at Dartmouth, Princeton, and Goethe University in Frankfurt, and for twenty-three years at the University of Wisconsin-Milwaukee, where he directed the graduate creative writing program and is currently professor emeritus of English. He is married to Ann Hill Siegel, a photographer, and lives on the coast of Maine.