Exploring Evolution Series: Is Character Displacement the Only Driver in Species Diversity?

The red-billed scythebill, a woodcreeper from the ovenbird family, has a long, curved beak. Photo: Joseph A. Tobias

Competition May Not Be the Driving Force of Species Diversity After All
http://www.wired.com/wiredscience/2014/03/bird-evolution/

by Emily Singer, Quanta Magazine

March 18, 2014

In 1982, a few large ground finches took up residence on the tiny island of Daphne Major in the Galapagos. Compared with the island’s existing population of medium ground finches, the invaders had an advantage: large beaks that could more efficiently crack open the seeds of the Jamaican feverplant, one of the island’s biggest bird food bounties. The newcomers began to flourish, eating many of the seeds and forcing the diminutive natives to forage for smaller options.

The two kinds of birds lived in relative harmony until 2003, when a two-year drought decimated the food supply for both species, pushing them to the brink of starvation. The bleak conditions favored a subset of medium finches that had smaller beaks; they had never been able to crack feverplant seeds, and their diet consisted solely of small seeds. Free from competition with the large ground finches, the smaller-beaked members of the medium finch clan survived the drought and passed along their petite features to the next generation. The average beak size in medium ground finches shrank in a swift and lasting change to the species. Peter and Rosemary Grant, biologists at Princeton University who have been studying Galapagos finches for 40 years, tracked the change, publishing their results in Science in 2006. It became a textbook example of an evolutionary tenet known as “character displacement.”

In Darwinian evolution, organisms compete for resources, and the winners get to pass their genome to future generations. According to these rules, two similar species using the same resources in the same environment will be forced to compete with each other. If both are to survive, they will need to become more distinct from each other over time. The famous naturalist E. O. Wilson, along with collaborator William Brown, dubbed this pattern character displacement in the 1950s and proposed that it explains much of the diversity among the world’s organisms.

Joseph Tobias, an evolutionary biologist at Oxford University, suggests

that character displacement may not be as common as previously

thought. Photo: Andre Baertschi

“It’s one of the main Darwinian ideas for explaining why species are different,” said Joseph Tobias, an evolutionary biologist at Oxford University. But some scientists, including Tobias, are now questioning the data supporting character displacement as a driving force in the evolution of diversity. A report published last year examining 144 studies found that few met the strongest criteria for character displacement. Scientists often failed to rule out other possible explanations, for example, or to show that the change resulted from a heritable trait. And in February, Tobias and collaborators published a large-scale study in Nature that questions how widespread character displacement is in nature. Focusing on ovenbirds, a family of birds that, like Darwin’s finches, have evolved different beak sizes, they found little evidence that character displacement was responsible for differences in the species if the ages of the species are taken into account. That is, given enough time, species tend to diverge, or become more different from each other, even without interspecies competition.

Tobias and Peter Grant, among others, contend that robust examples of character displacement are relatively rare. If that indeed means that the phenomenon itself is rare, rather than just difficult to reliably detect, scientists would need to reconsider the role of competition in the evolution of diversity.

“We’re not saying that character displacement doesn’t occur, but it’s probably rarer than people think,” Tobias said. “The implication of our study is that almost all of the species differences [in ovenbirds] that people have attributed to character displacement are actually the result of time.”

Home in the field view the provocative claim with skepticism. “I don’t think this spells the death of character displacement,” said Daniel Simberloff, an ecologist at the University of Tennessee, Knoxville who wasn’t involved in the project. “We need a lot more studies to know if this is a general phenomenon.”

A Swinging Pendulum

Like many scientific theories, character displacement has gone in and out of favor. After Wilson and Brown coined the term in the 1950s, “just about everyone saw it everywhere,” said Jonathan Losos, an evolutionary biologist at Harvard University whose 144-study review published last year examines the history of character displacement. “Any difference between coexisting species was attributed to competition.” But often there was little supporting it, and by the 1980s, the pendulum had swung the other way.

“It was a contentious period,” said Yoel Stuart, a postdoctoral researcher at the University of Texas, Austin, and co-author of the review with Losos.

In response to some of the criticism, scientists adopted more stringent criteria for concluding that character displacement was truly driving two species to become more different from each other. According to these guidelines, researchers should rule out other drivers of diversity, such as random chance or subtle differences in the two species’ habitats. Studies of character displacement should also show that the species under study truly compete, and that the differences among species, such as smaller beaks, are a heritable trait. In the 1990s, character displacement regained popularity as more rigorous studies emerged.

Anolis lizards in the Lesser Antilles tend to be medium-size if they live on an island without lizard competitors,

like this Plymouth Anole, but either small or large if two species share an island. Photo: Jonathan Losos

Losos’ studies of Anolis lizards in the Lesser Antilles highlight a major challenge in studying character displacement — different evolutionary histories can result in the same ecological pattern. In work published in 1990, Losos reported strong evidence that character displacement among lizards in the northern islands had resulted in the islands having one smaller and one larger species. The southern islands similarly had habitats with one large and one smaller species of the lizards. However, the likely explanation for this situation in the south was that the animals were two different sizes when they arrived. Without knowing the history of when two species come together, determining the forces at play can be difficult. The end result of both processes looks the same. “That’s one of the biggest sticking points in these studies,” Losos said.

Character displacement remains popular today, but some scientists insist that stronger evidence is needed to show that this phenomenon is the true driver of differences among competing species. “I think people have gone overboard and returned back to the state of play in the ’70s where people see character displacement everywhere,” Losos said, though he thinks that today’s studies present better evidence than their 1970s counterparts. Despite a huge proliferation in the number of potential examples of character displacement, conducted more rigorously than earlier efforts, fewer than 40 percent of the 144 studies that Stuart and Losos reviewed met most of the gold standard criteria. “With 20 years of rigorous research, we still have few cases,” Stuart said.

Peruvian Glaciers to Bolivian Deserts

An avid bird watcher from the age of 11, Tobias has traveled to the plains of Patagonia, Bolivian deserts and the high cloud forests of Panamanian volcanoes and has spied on about 5,000 species, more than half of the world’s birds.

These explorations revealed a pattern familiar to any naturalist: Where two similar species live in the same habitat, they are generally more different than species that live apart, said Tobias, now 44.

“The underlying assumption is that it’s because of character displacement,” he said. But Tobias began to doubt that assumption after coming across exceptions to the pattern. A study of Amazonian antbirds, for example, revealed that two species that compete for resources use very similar songs. “There may be many scenarios where competition does not produce divergent selection” and may in fact drive the opposite pattern, in which a specific characteristic starts to converge, Tobias said.

In 2007, Tobias and collaborators launched their in-depth study of ovenbirds, a diverse family of small, insect-eating birds that live mainly in South America. Different ovenbird species have adapted to rocky ocean shorelines, snowy mountains, scorched deserts and tropical rainforests. Like finches, ovenbirds have a variety of beak sizes and shapes, an important indicator of food preference that makes them ideal for studying evolution. In ovenbirds, “some [beaks] are long and down-curved, like a scythe, for probing into crevices in tree bark,” said Jason Weir, an evolutionary biologist at the University of Toronto who was not involved in the study. “Others have short dagger-like bills.”

Most studies of character displacement have focused on only a few species, but Tobias’ team compiled information on 350 ovenbird lineages, including species and subspecies, culling data from a vast set of resources: bird specimens from museums; recordings of bird songs, some more than a century old; geographical data collected during expeditions and from other sources; and a highly detailed evolutionary history of ovenbirds. “The scope of the study is pretty amazing,” said Stuart, who was not involved in the research.

To study the role of competition in evolution, Joseph Tobias and collaborators mapped out the evolutionary

relationships and variation in beak size among 350 lineages of ovenbirds. Image: Joseph A. Tobias and D. Seddon

For each lineage, the researchers compared the youngest, most closely related species living in the same area and the youngest, most closely related species living in different areas. When they looked at the data, they found a pattern that Darwin and most biologists would have predicted — the lineages living together were more different than those that lived apart.

But Tobias and colleagues suspected that species that cohabit tend to be older than those that live apart. That’s because new species usually form in isolation, so it makes sense that the youngest don’t typically share habitats, Tobias said. This pattern was familiar to some evolutionary biologists, but Tobias said few ecologists had considered the implications. “You can’t just compare things living together with those living apart,” Tobias said. As a species ages, it has more time to evolve, so “you have to take into account how old they are,” he said.

When the researchers accounted for the age of each ovenbird lineage — an unusual step in studies of character displacement — the differences vanished. “We find no evidence there is any kind of bump up in differences between lineages that come together,” Tobias said.

Instead, they found that the youngest species living together tend to be much older than the youngest species with distinct habitats; the former split from their common ancestor an average of 10 million years ago, compared to approximately 4 million years for the latter.

he researchers concluded that diversity isn’t driven by competition between cohabiting species. The differences they see may simply be the result of species having more time to evolve. “An important finding of their study is that it takes a long time for these species to diverge enough to be able to invade each other’s geographical range with little or no competitive interaction,” said Peter Grant, who was not involved in the study.

Indeed, previous research by Tobias’ team suggests that ovenbird species only start to overlap geographically once they are different enough to peacefully coexist. Species with the most similar beaks and ecologies took longest to cohabit, Tobias said. “It’s not necessarily that evolution isn’t happening; it’s just not driven by interaction among species,” Tobias said.

Evolution in Action

Having plunged itself into an evolutionary debate, the ovenbird study has received mixed reviews. Many experts applaud its unprecedented scope and the effort to look at the large-scale effects of evolutionary forces. “The overarching question they pose is an important one in evolution,” said David Pfennig, an evolutionary biologist at the University of North Carolina, Chapel Hill. One of the biggest issues in evolutionary biology is understanding how microevolutionary processes, mechanisms that happen within species, influence larger ecological patterns, he said. To what degree do they explain broad observations, such as the diverse range of body shapes we see? By looking at many species of ovenbirds, “this is one of the few studies that gets directly at this issue,” Pfennig said.

But some say it’s too soon to conclude that the findings will hold true more broadly. “All we can say is that there isn’t a strong signal for [character displacement] in this taxonomic group,” Weir said. “But it’s an extremely interesting starting point to explore this in other groups.”

It’s also difficult to rule out character displacement in this group of birds entirely. Pfennig points out that the traits that Tobias’ team examined in ovenbirds are mostly morphological — beak and leg size. But it’s possible that competition among species has driven the birds to evolve different behaviors, such as foraging during different times of day. “Many species undergo this kind of divergence,” he said.

The one behavior that Tobias’ team studied — bird song — did appear to shift in response to competitive species, but in the opposite direction than traditional character displacement would predict. Birds with overlapping ranges tended to have more similar songs, a pattern of convergence rather than divergence. Ovenbirds sing for largely territorial reasons, warning other birds to stay out. Tobias theorizes that a signal recognized by both the singer’s species and related competitor species deters more birds. This may represent a different flavor of character displacement, in which certain characteristics are driven to become more similar.

The findings also highlight the need to take evolutionary history into account in studies of character displacement, an issue that has been ignored in the past, largely because that data was hard to come by, Weir said. Many of the existing studies held up as examples of character displacement “are invalid without a time component,” he said.

Catching evolution in action, as the Grants did with their finches, is a powerful alternative, because researchers don’t need detailed evolutionary histories. “The real advantage is that you can actually see what happens,” Losos said. Theirs and other recent studies have demonstrated just how quickly evolution can occur, making it feasible to measure changes as they unfold. “Years ago, we thought evolution was too slow to see these things change, but it’s not,” Losos said. “Evolution can occur rapidly when natural selection is strong.”

One of the best opportunities for catching character displacement in the act comes from the study of invasive species. “We have inadvertently set up situations where character displacement might occur by introducing species that might be competitors,” Losos said. Despite the shortfalls of many existing studies, he said, “I am convinced that character displacement is a common phenomena.”

Scientists predict that the ovenbird study will provoke a round of similar research in the next few years to test whether the same pattern — that species differences are mostly linked to the age of the species rather than competition among species — is true in other groups. Tobias and collaborators are already expanding their approach to many more of the world’s birds, including other members of the roughly 1,200 species group known as suboscines. (Ovenbirds belong to this group). They also plan to study character displacement and other evolutionary questions for the 5,500 species of passerines, which encompass more than half the world’s bird species. The effort will rely on evolutionary maps currently under construction by researchers at Louisiana State University and elsewhere.

Scientists hope that in the next 10 years, studies that take species age into account, as well as the invasive species efforts that Losos describes, will clarify the role of competition in the evolution of diversity.

“My overall opinion is that character displacement may be fairly common,” said Peter Grant, whose studies of Galapagos finches are considered one of the strongest demonstrations, “though far from universal [and] generally small in magnitude.”

---

Original story reprinted with permission from Quanta Magazine, an editorially independent division of SimonsFoundation.org whose mission is to enhance public understanding of science by covering research developments and trends in mathematics and the physical and life sciences.

God and Time: The Mystery of the Incarnate God Eternal

Jesus - Incarnate "Immanuel" ("God with us")
see also, The Names of God in Scripture

In response to Tony Jones' earlier article on "God is Not Eternal" (posted further below) and the Biologos article "What is Time, and How Does God Relate to Time?" I thought I might reflect on each and pose some further questions and insights that seem to have generated additional thought and comment to my mind. - R.E. Slater

God and Time: The Mystery of the Incarnate God Eternal

"Ehyeh Asher Ehyeh" means "I will be that who I have yet to become."

- God (Ex 3.14)

An Eclectic Doctrine

Sometimes there are areas in Christian doctrine that you may properly be an eclecticist. I think the doctrine of God and time may be just one of those doctrines. I'm reminded of that every time we sing Troy Hatfield's song Matchless at Mars Hill where Troy unconsciously jumbles up the classical idea of God's unchangeableness with God's imputed changeableness: "A God who was, and is, and will be, constantly unchanging, immutable, unspeakable, full of grace, the God-man who came." A God who entered into our time and space and became. And there's the crux of it. "God was, and is, and will be."

A God who came into time and out of eternity. Into creation's experiences of time, and out of time's timelessness as the Greek Classicists and early Church Fathers had conceived of it. A God who became incarnate; Who lived with us and died for us. Who would renew all creation and mankind by His lived life and experiential death. Who was Himself, the timeless One, became the corruptible One - in the sense of bearing a dying body, and not bearing a sinful soul. Who became the changeable One at the time of His incarnation forward through to His death. Who now lives with all of creation's temporality as the eternally incarnated Redeemer of creation.

The Metaphysics of Becoming and Being

This ontological truth (ontology = speaking of God's being, attributes, and character) cannot be explained, understood, or imagined. It just must be accepted. A God who Himself had become and now is - mutable, changeable, temporal. Forever affected by the very creation He created within time and space. We cannot understand it. We cannot explain it. We can only state it and present it. The idea that a holy, eternal God can forever now be the Incarnated, holy, eternal God. No less divine but wholly glorified by His incarnation (which is what you would expect when finding anything touched by God's own presence). Who is both creature and Creator. Who is timeless Saviour become willful Redeemer. It is a paradox which is beyond our experience and metaphysical categories (metaphysics = simplistically, anything "spiritual." Something that is not physical but can be decribed meta-physically). We just know God is. Who once was and has become. Who, like us, was, is becoming, and will be, in the past, present, and future tense of our understanding.

It is this God that is the God who has entered into creation's time and become a God who is in process like we are today (a simplistic description of "process theology"). Who is in Himself experiencing the eternal process of "becoming and being" as the incarnate, resurrected Saviour of man. Who is no less flesh and blood than we are today. Whose future is our future when we die. And like us (anthropomorphism = bearing man's image) has become us, even as we are like Him (theo-morphism = bearing God's image) and are, and will be, in both the past-present-and-future sense of the word. We each share the other's image because of God's incarnation through Christ Jesus our Saviour. It is a mystery but one we must be mindful not to forget less we make of God an idol untouchable. One too holy, too distant, too unfeeling, from our own experiences. But whom we do understand can be all this and more if it were not for His holy incarnation that bridges the gap between our humanity and His divinity.

What Do We Mean by "God Being in Process?"

Now the question. Actually two.... If we have a lover, spouse, or friend, who forever was fixed in time from the first day we had met him or her, would that be satisfying to us today? To know someone who never changes. Never grows old with us. Whose experience of time is forever fixed in what was once was? Would this be satisfying to us? Would that friend, lover, or spouse, be able to meet our needs? Or match our experiences? Or breach our understanding of time and death? In a limited sense, yes. And in another sense of providing to us the comfort of our past, yes. But it would be akin to something similar to our fond memories of past loved ones who had died but are no longer with us today. Who were but who are no longer present with us in the continuing experience of our flesh. It's trials and travails.

However, loved ones who are in the process of dying (there's that word again. It speaks of both life and death and life beyond).... Who are remembered - perhaps like my father's long illness or, as a beloved child we once remember from many years ago as a parent - they are forever fixed in time and space and no longer able to reach out to us in meaningful ways that our current timeful experiences of life will demand. We would share ourselves with them but find a gap, an emptiness, there. An experiential gap that is unbridgeable - unless they were able to move forward with us in time and space to appreciate our experiences in the now. The here. The present. This is what we call relationship. Relationships must be living, not dead. We cannot share with a dying parent or loved one as they let go of this mortal veil of flesh to push onwards. We cannot commune with a pleasant memory of a past childhood or family life that no longer lives with us except in the past. This things are mortal. They are past. They continue forward only in our minds and hearts and not as living present relationships.

Thus, if we only had the memory of a dead God and Saviour than it is only that. A dead memory and not a living relationship. For God to be a living God is to be a God who must continue in His relationship with us into our future tense. And not only with us but with all of His creation in its future tenses. If He had only died and remained in the grave than there would be no present tense "I-Thou" relationship which could continue. To do this God must be resurrected from the grave, and raised into glorification, as the divine, but incarnate (not re-incarnated), God of the universe. (Pauline sidetrack: in a sense God is re-incarnated in us even as our past is re-incarnated in us. But not ontologically. But existentially = as something that is "live out through our past experiences." That is, we are not God. Nor are we other people. However, our relationship with God, or with others, will reproduce their mind, their heart, their passion, in-and-through us. Just not themselves, excepting God's Spirit of course, who lives in us, and through us, and permeates all creation, infilling it with His presence). A God of the universe who would continue with us alongside our time-and-experience, even as He would continue alongside of our own past when having died to it and parted from it. Otherwise there is no now, no here, no future promise, no there, is, and will be. All would be nothingness and nothing. Without future, hope, or promise.

This God must be a living God. Not a dead God only beheld from the grave. And not a timeless God who had never known incarnated. Or walked this earth as a flesh-and-blood but very mortal human. This God must be a God who continues forward both within time and space, and without (or outside) of time and space. Even so, it is this latter part that we seem to mangle and confused. For it is the "within" part that we do seem to understand more readily than the "without" part... that we do now have a living Saviour who is with us, but who is apart from us as divine Spirit.

Hence the concept of process.... Process theology is a dynamic (and not static) concept of God that says that God continues to live though dead - and not impassionately apart from His creation (sic, deism, pelagianism, in all their gnostic forms). But passionately. Who continues to become and be through creation's experiences. Or our own. Or the church's experiences in this world. Which is part two of our question. How can a dead God remain with us? At Calvary's cross He did die. A place where He was forever affected by His humanity by His divine death. A death that became as a result of His incarnation. A death that He would meet - as we each will - simply because He lived even as we do now today live, and breath, hunger and thirst, know tiredness, suffering, aches, and pain of heart. In this mortal flesh we do know that every living thing dies. We see it everywhere about. We know of only one man that never died - Elijah. A prophet of God who was raised up as a living, non-dead, being. But it is through Elijah's story, and that of Lazarus'  miraculous "raising from the dead," that we would understand Jesus' resurrection. An "alive-but dead-but made alive again" resurrection into the heavens by the hand of God.

Enter Radical Theology's "God is Dead"

It is this kind of Process Theology that can better inform us of God's continued presence with us which a Radical Theology will then acknowledge as an event described as the "Death of God" when reflecting on this momentous event. Which is quite unlike the movie depiction of the "God is Dead" movement that serializes a Hollywood charicature of the "Death of God" movement. In reality, a true theology will take this event's implications very seriously. That God did die and that we must now know what it means for our present tense society, humanity, creation, church, Christianity, and future expectations. But we've strayed off topic again and must return to the topic at hand....

A Process Theology can better handle God's death when coupled with His resurrection, and not apart from it. Even as we can best understand God's death when beheld in the light of His resurrection. But it is the "without" part of God dwelling "outside of" time and space that we may have the greatest struggle with. And in fact, we must now admit into our definitions and classical ideas of "eternality" that God is no longer the unaffected eternal God. But the affected eternal God who must now dwell within all time and space. Who no longer is separate from it - if He ever really was. That perhaps classicism itself is to blame for making this God we worship so timelessly eternal that we see Him too far away from ourselves. If we say that God is love than how do we know that this God can love?

The very idea of God's "love and grace" seems meaningless without its actual experience of love and grace (whether before God's Incarnation or after it). Have you noticed that platonic love is seldom written about or moanfully sung?. But romantic love - deeply entangled love - is. It fills all the music industry with its messiness and frailty. Its crucible of a heaven-and-hell painfully experienced deeply within the souls of our being. Our anger and frustrations. It affects everything we say and do - our passions, drives, and nature. However, divine love cannot be meaningful if it dies in the grave, or never lived at all. It must somehow live in the present and future tenses of its expectations of being and becoming.

And yes, spirits, even divine Spirits, must admit some form of eternality because spirits by our very definition and ideas are seemingly "unaffected" by timeful events.... Or so we think. However, it is that very idealised human idea of "spirit" that must change from its classical sense to its process sense. We can no longer think of God as Spirit without thinking of God as an affected and affecting Spirit. It would be both biblical and right to aver that God ever loved in eternity even as He will ever love throughout eternity everlasting. But even more so, as our Incarnate, glorified God, He now is one with His creation. This divine love has been made plain to us through Jesus God's Son and very Self come among men.

Otherwise how can a dead God continue to love if we are to take the "Death of God" seriously? How can a dead God be alive and present with us now? How can His grace and mercy, peace and justice, hope and force of life, be our present guide and salvation? Nay, this God who is dead must somehow live. And live both within and without eternity as both divine Spirit and incarnated God. He must be resurrected from the grave. From hell. From the separation of Himself from Himself even as the Son was forsaken by the Father. He must be a God who is glorified on the basis of His incarnation and defeat of death, grave, and hell, by penalty and resurrection. Even as the believing son or daughter of God must even so live beyond death. He must be a God who lives with us in this life even as He will live with us in the next life to come. In eternity everlasting.

Which doesn't mean that our dead loved ones might commune with us now in this life as they once had.... But for the Christian, there is the strong knowledge that those dead loved ones will be communed with again on the other side of the grave. And until then they rest in God. They remain in Him even as we shall someday rest in God. And know that by the saving work of Christ our Saviour - based upon His own death and resurrection - that we will likewise rise with Jesus into the fellowship of God everlasting. Who in Himself was, and is, and ever will be, the Prince of Life. Our Prince of Life. Our Promise and Keep. Our strong fortress that prevails over death, the grave, and even hell itself.

The Incarnate God Who Died and Lives Again

Which brings us back to thought number two... how does a God who died now live? We have answered it on a Spirit level (or metaphysical), but we must also answer it on an existential level (an experiential, knowledge level, on the plane of our being). The short answer is that God is dead and we must acknowledge His death (back to Radical Theology again). This too is a paradox which forces us to admit that the Eternal, Unchanging One is no longer eternal and unchanging. That He has died and no longer lives as He once was apart from Calvary's Cross. And this is the part we will struggle with so firm our convictions that He walks with us "in the garden alone" as the old hymn says. That His Spirit does ever live and is with us by His eternal presence. And yes, this is true. But it is also true that His discourse with man is not like it once was in the Old Testament. And here is the tricky part then. Just what is it now since the days of the New Testament? Since the days of His death and resurrection?

I might offer one suggestion. That God continues today with His church (and with all of mankind) through His infilling Spirit of Pentecost. That is, it is through God's very Spirit that He communes with man today (though I suspect that even in the Old Testament He did so when speaking to the saints and priests of old, and beholding their commune with God). For this old world to see God means that it must see God through us, His church, His body and bride. How? By His own wounded hands and feet which act through us by His living miracles of healing, prophesying, evangelizing, of doing good works through us. We are His tongue and words (logos). His presence (spiritos). His feeling and composure (pathos). His nurture and grace (agapos). Truths which will place a lot of responsiblity upon our shoulders when we think of it in this way. Which doesn't mean that God by His Spirit can do nothing alone apart from us. But that, like with the Patriarch's and Israel's spiritual responsibility in their day, even so the church must now bear the love and grace of God, and the burden of the Lord Jesus Christ, through us, His living church.

Henceforth, and forever now, do we know that the God who lived, and who has died, must now live again in the resurrected sense of His living church. Who is a God who still reaches out through His Spirit to infill, transform, and conform, our very lives so that they may reach out to friend and family, foe and enemy, in the love and grace and divine power of His Almighty, Holy Spirit. We are not alone. We have a living God who is not dead. But a God who did die and lives again. Who is our pattern for both life and eternity. Who is in Himself the unexplainable One. Our mystery and paradox. Our enigma and riddle. But One whom we trust, and know, and desire to live and serve though all our mortal-immortal life. Even so dear Lord come. Come into our lives and help us die to sin's deaths and live to graces sustaining affects. In all our weakness. In all our frailty. By your strength and help and Spirit. Amen.

R.E. Slater

March 19, 2014

Jesus - Incarnate "Immanuel" ("God with us")

Aaron Niequist live at Willow Creek Church singing Matchless -

http://www.youtube.com/watch?v=RGF-Q-6EmbM

Matchless
by Troy Hatfield
Mars Hill Church, Grand Rapids, MI

Long before
Our time began
Long before I was

Heaven rang--creation rang
The matchlessness of God

Majesty unspeakable
We boldly bless Your name

In awe of love--in awe of grace
The God, the man who came

Praise to the constantly unchanging

You were
You are
And You will be

You were
You are
And You will be

God even though immutable
Revealing still today

The story moves--our parts still prove
Significant in ways

We praise the constantly unchanging

You were
You are
And You will be

You were
You are
And You will be

Beauty, glory
Just and holy
Righteousness and truth
Faithful leader, gentle healer
Matchless God are You

Beauty, glory
Just and holy
Righteousness and truth
Faithful leader, gentle healer
Matchless God are You

You were
You are
And You will be

You were
You are
And You will be

Hallelujah
Hallelujah
Hallelujah
Hallelujah
Hallelujah
Hallelujah
Hallelujah
Hallelujah

©2003 zonkeydonkeytunes




continue to subtopic and discussion
under "God and Time" here -

Index to past articles on "Particle Physics, Quantum Science, and the Universe"

* * * * * * * * * * *

God is Not Eternal

http://www.patheos.com/blogs/tonyjones/2014/02/12/god-is-not-eternal/#more-9825

by Tony Jones

[additional remarks by r.e. slater]

February 12, 2014

Writing a book on the atonement is like peeling the layers of an onion. Every theological dilemma you [think you] solve only brings up two more dilemmas. So it was that I needed to write a section in the book on God’s relationship to time, because it seemed to make no sense to talk about God’s relationship to Jesus’ crucifixion unless I could explain God’s relationship to time.

So a couple weeks back, I wrote a post arguing that God is not outside of time [that is, in the classic description of time. But that God is alongside of, or within time, in the process sense of time. - r.e. slater]. When reading that, Keith DeRose sent me Nicholas Wolterstorff‘s classic essay, “God Everlasting” (in Contemporary Philosophy of Religion, New York: Oxford, 1982).

In that essay, Wolterstorff argues that God is not eternal, God is everlasting.

His argument proceeds thusly:

1) The biblical narrative clearly tells of a God who changes, and any hermeneutic that denies this is tortured.

2) Any being who changes is necessarily, in part, temporal.

3) “Eternal” is a totalising characteristic. It is not possible for a thing to be partly temporal and partly eternal.

4) Therefore, God is not eternal.

Money quote:

What I shall argue is that if we are to accept this picture of God as acting for the renewal of human life, we must conceive of him as everlasting rather than eternal. God the Redeemer cannot be a God eternal. This is so because God the Redeemer is a God who changes. And any being which changes is a being among whose states there is temporal succession. Of course, there is an important sense in which God as presented in the Scriptures is changeless: he is steadfast in his redeeming intent and ever faithful to his children. Yet, ontologically, God cannot be a redeeming God without there being changeful variation among his states.

Some will argue that God could be eternal and still involved with time. Wolterstorff debunks that claim in a section that begins,

As with any argument, one can here choose to deny the premisses rather than to accept the conclusion. Instead of agreeing that God is fundamentally noneternal because he changes with respect to his knowledge, his memory, and his planning, one could try to save one’s conviction that God is eternal by denying that he knows what is or was or will be occurring; that he remembers what has occurred; and that he brings about what he has planned. It seems to me, however, that this is clearly to give up the notion of God as a redeeming God. And in turn, it seems to me that to give this up is to give up what is central to the biblical vision of God. To sustain this latter claim would of course require an extensive hermeneutical inquiry. But lest someone be tempted to go this route of trying to save God’s eternity by treating all the biblical language about God the redeemer as either false or misleadingly metaphorical, let me observe that if God were eternal he could not be the object of any human action whatsoever.

For me, in solving the enigma that is the crucifixion of Jesus, God’s relationship to time is essential, and Wolterstorff opened a new vista of understanding in this essay. It’s that last sentence that really seals it for me. I don’t see any logical way that an eternal being could be engaged in temporal human affairs, and surely not in the way that’s described in the Bible.

What do you think is God’s relationship to time?

- Tony

Common Sense Christian Wisdom from my friend Rance...

I have a Facebook friend by the name of Rance who occasionally will rattle off a string of his beliefs on the popular social media site. As I read them I find myself simply nodding my head and thinking, "Yup, yup, yup, ok, yup, got it, check... and so on" in a long list of agreements like we were old friends from way back when really we're quite new friends from not so long ago.

What Rance has that I admire is his simply-said, common sense Christian wisdom, that tells it like it is while refusing to buy the popular line of Christianity that the media would have us believe (if not the Christian presses themselves). Its a kind of street wisdom that doesn't pull any punches unless they're headed right for your nose, and when you get back up off the ground you would mostly likely say, "Thank you. I needed that," in as kindly a manner as you may.

So, from time-to-time, with Rance's permission, I'm simply going to rattle off a "Rance segment" to allow his heart and mind speak to us from a long life of living, serving, conversing, reading, and "figuring things out." Kinda like a "thinking man's" list of proverbs and observations that have been hard won and had gained.

At the last, I would simply like to say "Thank you Rance" for being willing to ramble so we might gain a little insight into a Christianity that has become too harsh, or uncaring, to the guy or gal on the street. Jesus spoke plainly... and when He did He spoke in love. In tenderness. In humility. And with a lot of wisdom.

Peace,

R.E. Slater

March 18, 2014

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A Common Man's Journal

Quotes from my friend Rance

I suppose, in broad sense, I should be viewed as a conservative Evangelical, but not as an Evangelical conservative. My conservatism shows up mainly in my solid core commitments to orthodox theology. I believe in the Apostles Creed and affirm faith in the one Creator of heaven and earth, the saving work of Jesus Christ, and the gracious enabling of the Holy Spirit in my life and the life of the ...entire church. I await the renewal of the world and the resurrection from the dead at the future royal appearance of God's Son.

However, unlike many of my good friends and colleagues, I am no longer an Evangelical conservative. Politically, I fit more comfortably in the intellectual company of folks like Ron Sider, Greg Boyd, Tony Campolo, N. T. Wright, Roger Olson, Rachel Evans, and Jim Wallis than I do with folks like Marvin Olaski, Franklin Graham, Doug Wilson, and Carl Thomas.

In addition, I find myself affirming of the following 10 ideas:

1. That the biblical theological view of creation is not incompatible with the theory of evolution.

2. That the Bible can be primary and inspired without being infallible and inerrant.

3. That one can somehow be both pro-life and pro-choice.

4. That one can believe in wealth distribution without believing in Socialism. 

5. That one can find many strong examples of Christians from the past who were politically, theologically, socially, and economically progressives.

6. That one can affirm both the sanctity of traditional marriage and the freedom for same-sex unions.

7. That one can believe in debt forgiveness for poor nations. 

8. That one can be patriotic without being nationalistic.

9. That one can be loyal Americans while refusing as Christians to bear arms or go to war. 

10. That one can peaceably share this great country with atheists, agnostics, humanists, Muslims, and foreigners.

- Rance

Exploring Evolution Series: Biologos - The Amazing Story of Carbon

Word and Fire: The Amazing Story of Carbon, Part 1: Fire

http://biologos.org/blog/word-and-fire-the-amazing-story-of-carbon-part-1-fire

Today's entry was written by Paul Julienne. Please note the views expressed here are those of the author, not necessarily of The BioLogos Foundation. You can read more about what we believe here.

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Before there ever could be biomolecules, or a genome, or living beings, there had to be carbon and the other chemical elements that are essential to life. The science of carbon is remarkable, and the more one knows about it, the more one can stand in awe of the amazing universe in which we live. My career in physics—in particular, the quantum physics of atoms and molecules and light at the interface of chemistry and physics—has taught me the depth and power of the natural sciences to understand the world. It is a pleasure to be able to contribute to the Biologos blog a few thoughts about carbon: how it came to be made in the fire of the stars of the early universe and how it enables the remarkable chemistry of life written out in the words of the genome. Putting it all together draws on connections between atomic and nuclear physics, cosmology, quantum theory, chemistry, biology, and what science is all about in the first place.

I tell the story based on all the positive knowledge we have from the sciences. Does it have anything to do with God and humanity? Tomorrow's post will help you decide. First, let us take a whirlwind tour of the picture science gives us of the early universe and of the origin of the chemical elements.

According to the best current measurements, our universe is approximately 13.8 billion years old, and had a long history before there was life on earth. After an initial “Big Bang,” the universe rapidly expanded and cooled so that after a few minutes the present abundance of most of the atomic nuclei in the universe had been established, about ¾ hydrogen and ¼ helium, plus a trace of lithium. The simplest atomic nucleus is hydrogen,1H, having a single positively charged proton, whereas the helium nucleus, 4He, known as an alpha particle, is comprised of two protons and two neutrons. In this early stage of the universe, there were no nuclei of species heavier than 7Li (lithium with 3 protons and 4 neutrons) such as carbon, oxygen, or iron.

After about 380,000 years of expansion and cooling, the positively charged hydrogen and helium nuclei recombined with negatively charged electrons to make ordinary electrically neutral hydrogen and helium atoms. The universe was still mostly uniform without clumping into galaxies and stars, but once it was composed primarily of neutral atoms, it became transparent to light, that is, light could propagate freely throughout the universe. This light has continued to cool, and its afterglow is known as the microwave cosmic microwave background radiation.

This picture shows the cosmic microwave background radiation measured by the European Space Agency‘s
Planck satellite observatory. The irregularities reveal fluctuations in the density of the 380,000 year old
universe that correlate with the future clumping of matter into stars and galaxies.

What about the heavier elements? Since stable nuclei heavier than lithium didn’t exist in the very early stages of the universe, where did they come from? How were they built up?

After the separation of light and matter in the early universe, the hydrogen and helium began to clump into large clouds of gas that under the influence of gravity condensed into galaxies and stars. The first stars and galaxies had already formed by the time the universe was one billion years old. It turns out that the heavier elements can be made in the hot interior of stars by fusing together lighter nuclei via sequences of nuclear reactions that can explain the observed abundance of these elements. It is only in the dying phase of certain types of stars that temperature and pressure is sufficiently high that these fusion processes occur to make the heavier elements. These elements are then expelled into the surrounding interstellar medium by the exploding star at the end of its life. The clouds of gas formed this way later condense into new stars, such as our sun, some of which have accompanying planetary systems. Consequently, before there could ever be carbon, there had to be a first generation of stars to be born and die. In other words, given what we understand about the laws of nature and star formation and evolution, the universe actually needs to be billions of years old before carbon-based life could be present.

How the heavier elements are made in stars was worked out in the 1940s and 1950s through discoveries about nuclear physics and nuclear reactions. A classic paper published in 1957, “Synthesis of the Elements in Stars,” by Margaret and Geoffery Burbidge, William Fowler, and Fred Hoyle, laid out the basic framework that remains with us today. Fowler received the 1983 Nobel Prize in Physics for his work on nucleosynthesis, the two Burbidges received the Gold Medal of the Royal Astronomical Society in 2005, and Hoyle was later knighted for his work in astrophysics and was awarded the prestigious Crafoord Prize of the Swedish Academy of Sciences in 1997 for his work on the formation of the elements in stars.

Getting the heavier elements requires first making a carbon nucleus, which is very difficult. Making 12C requires that three alpha particles, 4He, fuse together. This is called the triple-alpha process, but it is impossible at the 15 million degree temperature inside a normal star like our sun, because the average velocity of the alpha particles is too low for them to overcome the very strong repulsive electric forces between the positively charged4He nuclei. Hans Bethe had already shown in 1939 that a temperature of 1 billion degrees would be required for such repulsion to be overcome. But such a high temperature does not occur even in stars.

Fred Hoyle

In 1953 the young astrophysicist Fred Hoyle realized that accounting for the relative abundances of carbon and oxygen in the universe required that there be a special quantum state of the 12C nucleus that would allow it to form in stars at temperatures around only 100 million degrees. The postulated quantum state, which may or may not exist, had to have just the right properties to allow fast enough production of 12C nuclei but to prevent their destruction by rapid conversion to 16O upon fusing with another alpha particle. While visiting the Kellogg Radiation Laboratory at Caltech, Hoyle told William Fowler and his colleagues and students there about his prediction, and it was verified through laboratory experiments that the needed state existed at close to the predicted value. With this knowledge in hand, Hoyle and others could then understand how the heavier elements could be made through sequences of nuclear reactions starting with 12C and 16O, and the foundation was laid for understanding how all the heavier elements came to be.

All the elements needed for life are synthesized in the late stages of the life cycle of certain stars. Without the Hoyle state in the triple alpha process, we would not be here as living beings who can understand such things. In an article entitled “The Universe: Past and Present Reflections,” published in the Annual Reviews of Astronomy and Astrophysics in 1983, Hoyle wrote the following (Vol. 20, p. 16):

From 1953 onward, Willy Fowler and I have always been intrigued by the remarkable relation of the 7.65 Mev energy level in the nucleus of 12C to the 7.12 Mev level in 16O. If you wanted to produce carbon and oxygen in roughly equal quantities in stellar nucleosynthesis, these are the two levels you would have to fix, and your fixing would have to be just where these levels are actually found to be. Another put up job? Following the above argument, I am inclined to think so. A common sense interpretation of the facts suggests that a superintellect has monkeyed with physics, as well as with chemistry and biology, and that there are no blind forces worth speaking of in nature.

Hoyle was known for making controversial claims. While few scientists would claim that the science would establish that “a superintellect has monkeyed with physics,” the Hoyle state does provide another example where the laws of physics of our actual universe are fine tuned such that carbon-based life is possible.

Be sure to check out tomorrow’s post to learn more about the intersection of science, carbon, and life.

Paul S. Julienne recently retired from his career as a physicist at the National Institute of Standards and Technology and the Joint Quantum Institute of NIST and the University of Maryland. He has published over 200 scientific papers on the theory of quantum processes in atomic, molecular, and optical physics.

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Word and Fire: The Amazing Story of Carbon, Part 2: Word

http://biologos.org/blog/word-and-fire-the-amazing-story-of-carbon-part-2-word

Today's entry was written by Paul Julienne. Please note the views expressed here are those of the author, not necessarily of The BioLogos Foundation. You can read more about what we believe here.

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Part 1 of this article told us how a special quantum state in the compound state of three alpha particles plays a critical role in the production of carbon and the rest of the heavier chemical elements in the hot interior of a dying star. Carbon made this way became part of the gas cloud that eventually condensed into our sun and its planetary system, and became part of our earth where we live. Let us now skip to today and reflect a bit on science and life—life as we know it as ordinary human beings and life as made possible by the unique chemistry of carbon. Among other things, this chemistry makes possible the molecules of life, including the remarkable DNA molecule that is the basis of molecular genetics and the human genome.

Dying Red Giant carbon-rich star U Camelopardalis, 1500 light years from the
earth,  blowing off a shell of hot gas. From the Hubble Space Telescope.

I had the pleasure of knowing Francis Collins even before he founded BioLogos. We both shared the concern that too many people in our churches, in the general public, and in the sciences were being influenced by the widespread misconception that science and Christian faith must be in conflict with one another. The reality of the situation is much more interesting and subtle than can be captured by such a generalization. We also shared the concern that young people going into the sciences need not have to face a dilemma of choosing between science and their faith, as if one excluded the other. I count among my friends a number of scientists who, like Francis and myself, see no conflict between their science and their belief in God.

The word “science” comes from the Latin scientia, knowledge. Scientists seek understanding of the world. What it is really like? How does it work? Nobel laureate physicist Richard Feynman said that a really important aspect of science “is its contents, the things that have been found out. This is the yield. This is the gold. This is the excitement, the pay you get for all the disciplined thinking and hard work.” Most scientists I know will share Feynman’s passionate enthusiasm about understanding the world.

Scientific knowledge is derived from the scientific method of observing the world as it is. Science has been enormously fruitful and successful. Knowledge about the way the world works has enabled the marvels of modern communication, transportation, and medicine. Yet science is concerned with the world on scales of time and distance that extend well beyond those encountered in everyday human life. Much of what science discovers about the world is very counterintuitive—it surprises us. This is certainly true of the quantum theory, which is one of the most successful theories of contemporary science in its highly quantitative characterization of the atomic and subatomic world. Yet, the quantum world has dramatically different properties than our everyday world, so much so that Richard Feynman said about it: “Nobody knows how it can be like that.” Even now, over 50 years after the discovery of the theory, in spite of agreement on its mathematical formulation and the accuracy and power of its predictions, physicists do not yet agree on how the theory should be interpreted.

That the universe is intelligible is an utterly remarkable fact. It is understandable to our human minds even if it still holds mysteries for us. Perhaps one of the most profound things that Albert Einstein said is: “The most incomprehensible thing about the universe is that it is comprehensible.” Why is it that we human beings can actually understand the universe so well? Why are we so passionately driven to try to grasp the truth about it, and are satisfied when we do, however incompletely? Could it be that we are meant to be this way?

The eminent French physicist and philosopher Roland Omnes writes in Quantum Philosophy: Understanding and Interpreting Contemporary Science (1999) about how science, quantum physics in particular, is formal and abstract in its formulation, yet incredibly fruitful in its precise and quantitative characterization of Reality. Omnes asks:

How can science exist? Or: How is science possible? The obviousness of this question and the silence surrounding it echo Aristotle’s beautiful words: ‘Like night birds blinded by the glare of the sun, such is the behavior of the eyes of our mind when they stare at the most luminous facts.’ … The answer is perhaps as obvious as the question: science is possible because there is order in Reality. …The whole of science suggests such an answer, but science alone cannot establish or even formulate it, for this assertion is beyond science’s own representations.

There are some questions that science cannot answer. Even understanding why science is possible requires, as Omnes puts it, “leaving science and entering metaphysics.” When we do the latter, we must make critical judgments about the nature of the world based on considerations that lie beyond science per se. It takes wisdom to do that. Elsewhere in the book, Omnes does not hesitate to use an ancient philosophical term to characterize the order behind Reality, namely, its Logos, that is to say, its fundamental “logic,” “principle,” or ”ground.”

This subtle term Logos is also used in the familiar opening verse of the Gospel of John: “In the beginning was the Word [Logos], and the Word was with God, and the Word was God…. All things were made through him…” The term “Word” used here to translate the Greek λόγος has a significance that is clearly more than literal, situating the Logos at the ground of all there is, at the root of all intelligibility and order in the totality of Reality. John’s verse is also an echo of the opening words of Genesis, where God creates by speaking. The wonderfully spare and austere language in the first chapter of Genesis also tells us that human beings are made in the image of God. John goes on to tell us something even more remarkable: “And the Word became flesh and dwelt among us.”

John identifies the Word-made-flesh with Jesus of Nazareth, the one who shows us—uncovers for us—the very character of God. Here is the heart, the logic, the Logos, of the whole gospel: the paradoxical story of Jesus and his self-giving, self-sacrificial love communicates to us the key to the essential nature of Reality, about the cosmos and humanity. It is the Logos-become-flesh who shows us how to bear the image of God rightly and flourish as human beings. I have yet to find anything from what I have learned from the natural sciences—physical, chemical, biological, or bio-medical—that necessarily conflicts with a robust Christian theology centered on the person Jesus of Nazareth understood as being fully God and fully human.

Words are an essential part of our humanity. Perhaps like science itself we take our words too lightly. How are words possible? Words are the basis for language by which we communicate to one another. Words tumble and cascade one after the other, yet they convey a whole. They make sense, at least if we speak the language. They communicate information. The scientific knowledge by which the universe is intelligible is communicated by words. Words can also communicate emotions, love and anger, and express poetry. They describe. They convey a tone, a mood. Words can be written or spoken. Yet words can be hopelessly inadequate to the task of conveying what we would like to express. Can we even put into words the aroma of a cup of coffee, if we wanted to express what it is like to another person who had never experienced it?

Now is a good time to re-enter the story of carbon. The incredibly rich life of a cell, and by extension an entire living organism, is based on the special chemistry made possible by the specific molecular bonding properties that a carbon atom has with another carbon atom or with different atoms like hydrogen, oxygen, nitrogen, and many others. There is a large subfield of the chemical sciences known as “organic chemistry” that studies the structure, properties, and reactions of such carbon-containing molecules. There is an enormous variety of such molecules, since carbon can bond with other carbon atoms to form long chains with branching substructures. Different kinds of molecules make proteins, fats, carbohydrates, hemoglobin, insulin, DNA, and all the other kinds of molecules involved in life. The field of “molecular biology” studies these molecules in their biological context.

Most molecules have a well-prescribed structure and shape, conforming to solution of the quantum mechanical equation that describes the ensemble of atoms that comprise the molecule. Molecules will normally have a definite structure that corresponds to the solution of the equation that has the lowest energy for the sequence of atoms in the molecule. Quantum chemists routinely do large-scale computer calculations of such structures on moderately sized molecules. The DNA molecule that bears the genetic information in the genome of an organism is quite different from most biomolecules. While the DNA has a definite double helix structure, the genetic code is carried by the sequence of “base pairs” of 4 possible base molecules, with any three pairs in the sequence coding for one of 20 possible amino acid molecules. These base pairs that make up the genome are strung out along the sugar-phosphate backbone of the double helix structure in a sequence that is energy-neutral, that is, not determined by energetic or chemical bonding requirements. Consequently, any sequence is possible, and the actual sequence serves as the letters of a genetic alphabet that the cellular machinery reads to fabricate the particular sequence of amino acid components to make specific proteins needed by the cell. The sequence is thus neither predetermined by chemical forces nor random, but carries information of great complexity that enables the cell to grow and function and replicate accurately. The same basic genetic alphabet is universal for all life forms on earth, whether animals like human beings, plants, bacteria, or viruses.

Schematic representation of the genetic code in a DNA molecule.
From the U.S. Department of EnergyGenomic Science program website.

One of the most far-reaching revolutions in thinking in the contemporary sciences is to view the world in terms of information and its transformations. Loosely speaking, information concerns how the world is organized into complex, meaningful patterns instead of randomness. In the biological sciences, this view hinges around the realization that information is at the center of life. Whole new university departments and scientific journals are being set up in the new field of bioinformatics. One accomplishment of the human genome project is to lay out the details in our DNA like a vast encyclopedia of words. Geneticists talk of genes “expressing themselves” through the natural processes in our cells, depending both on the genome and epigenetic factors beyond the DNA sequence.

In the view of contemporary biology, we are, in a sense more literal than figurative, embodied words. The words in the genome take flesh and make a living being. They become alive in a unique confluence of atoms, molecules, cells, and organs that make a coherent whole, a living person who can understand, speak, and love. The chemistry of carbon-bearing molecules makes this possible. In the case of the remarkable human animal, we find a being with the capacity to comprehend the whole universe that makes his being possible, who can comprehend the triple alpha process in ancient stars that enabled him to be here.

If we have the eyes to see, is it too much a stretch of the poetic imagination to think of each one of us, as it were, as being a unique utterance of God, a “word” spoken with an invitation to respond? Perhaps this helps us gain new insight on what it means for humankind to be created in the image and likeness of God. Perhaps the ancient Psalmist said more than he intended when he penned (Ps. 19:1-4a):

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. [NIV]

Word and fire: The fire in ancient stars has forged the material in which the words in the genome are written. We know this from science. This is possible because there is order in Reality, a Logos, a ground, that lies behind all that is and gives it coherence. The story of Jesus identifies the Logos and enables us to see that Reality is intelligible because the Word comes before the fire. This is not science, but represents wisdom beyond science to enable us to see why science is possible in the first place. Word begets words. It is really just as simple and deep as that.

Additional Reading:

Alister McGrath, A Fine-Tuned Universe: The Quest for God in Science and Theology (Westminster John Knox Press, 2009)

Sir John Polkinghorne, Quantum Theory: A Very Short Introduction (Oxford University Press, 2002) andScience and the Trinity: The Christian Encounter with Reality (Yale University Press, 2004)

Endnote:

A word is in order about what a quantum state is. Ordinary everyday objects can have any energy content. By contrast, a collection of quantum particles bound together in a small volume like an atomic nucleus will have a set of specific quantum states, each having a discrete quantized energy and a distinct set of “quantum number” labels. The Hoyle state is actually what physicists call a resonance state, namely, a state of a compound system that has the same energy as the individual particles that come together in a collision to form it. In this case the 12C Hoyle resonance state made from three alpha particles is an excited state that emits a gamma ray photon and decays to a stable, lower-energy form of 12C. Since the spread of energy in the hot alpha particles is actually quite small compared to the typical spread in energy between different quantum states, there is no guarantee that such a resonance would exist. That such a resonance occurs is a feature of the actual laws of physics being what they are. The actual rate of 12C production is extremely sensitive to the subtle details of the resonance, and the detailed dependence on temperature is still being worked out in papers being published in the scientific literature. Only recently has a fully first-principles mathematical calculation with powerful computers been possible to calculate the energy of the Hoyle resonance. This is explained in detail here.

Paul S. Julienne recently retired from his career as a physicist at the National Institute of Standards and Technology and the Joint Quantum Institute of NIST and the University of Maryland. He has published over 200 scientific papers on the theory of quantum processes in atomic, molecular, and optical physics.