This piece was the first in a two-part series. It was published on December 29, 2019 in the Weekend Nation, a weekend newspaper published nationally in Malawi. It was published under the title “Big Bang and evolution (Part 1).”
The WhatsApp post on this Christian group, of which I am a member, featured a serious-looking white man holding a placard on which was written something to the effect that if you want your children to be corrupt then you should teach them about the Big Bang and evolution. The implication being that teaching your children anything other than that God created the world and everything in it in six twenty-four-hour days is corruption. According to the Bible, God created the universe in six successive days: starting with generating light on the first day; separating the sky (atmosphere) from the seas (hydrosphere) on the second day; separating the hydrosphere from the land (geosphere), and creating the plants on the third day; creating the sun, moon and stars (cosmos) on the fourth day; creating the fish in the waters and the birds on the fifth day, and then, on the sixth day, the animals on land. God created man—Adam and Eve—also on the sixth day, and he rested on the seventh day. Should the six-day creation story in the Bible be taken literally?
Some Thoughts from Theologians
Several prominent Christians of the Early Church, such as Origen of Alexandria (184-253) interpreted the story of creation in Genesis allegorically. At least one of the four great fathers of the Western Church—Ambrose, Jerome, Augustine of Hippo, and Pope Gregory—realized that a literal interpretation of the Biblical six-day creation story did not jive with common sense. The problem of interpreting Genesis vexed Augustine (396-430) considerably, and it is a feature in many of his published works. Writing in On the Literal Interpretation of Genesis: An Unfinished Book, which was published around 393, Augustine, like Origen, reasoned that it is the light from the sun relative to the rotating earth that creates one twenty-four-hour day. Then how can it be said that God generated light on the first day when he had not yet created the sun, which was created on the fourth day? You need the sun to have a day. So where in the universe did God get the first day without a sun to define the hours of the day? This line of reasoning seemed to support a figurative rather than a literal interpretation of the Biblical six days of creation. Stated differently, the six days of creation are to be taken literary and not literally: they are a literary flourish meant to simplify for men the things of God. Augustine surmised that God must have created the universe in an instant. In a sense, the Big Bang shows that he was partly right.
Still the Big Bang and evolution remain controversial, and merely admitting their compatibility with the Biblical version of events can be costly, as Bruce K. Waltke, a noted evangelical Christian scholar of the Old Testament, learned when in 2010 he lost his job at Reformed Theological Seminary (RTS) in the United States, apparently for giving an interview on the BioLogos website that seemed to endorse the credibility of both versions. (This is a website that promotes the compatibility of science and religion.) On the other hand, no less an authority than Pope Francis has admitted that the two versions are not mutually exclusive. Speaking at the inauguration of the bust of Pope Benedict, his predecessor, on October 27, 2014, Pope Francis said, “The Big Bang theory, which is proposed today as the origin of the world, does not contradict the intervention of a divine creator but depends on it. Evolution in nature does not conflict with the notion of Creation, because evolution presupposes the creation of beings who evolve.” In the same address, he also said, “And thus Creation has been progressing for centuries and centuries, millennia and millennia, until becoming as we know it today, precisely because God is not a demiurge [imaginary supernatural being] or a magician, but the Creator who gives life to all beings.”
In fact, the Catholic Church’s position on the Big Bang and evolution has been becoming increasingly accommodating since Pope Pius XII (1876-1958) published his encyclical Humani Generis in 1950, but there is no official position stated in the Catholic Catechism. Still, in 1992, Pope John Paul II (1920-2005) expressed regret at the way the Catholic Church had handled the Galileo Galilei (1564-1642) affair in 1633, when the scientist was placed under house arrest because of his declaration that the earth rotates around the sun, which was considered a heresy because at the time the earth was thought to be the center of the universe. It would appear the Catholic Church has learned that science and religion compliment rather than antagonize each other, and there is a place for both in understanding nature and the universe.
The Big Bang Theory
One of the scientists who contributed to our understanding of nature was a Belgian priest and astronomer—George Lemaitre (1894-1966). Although other individuals had done some prior work relating to what would come to be known as the Big Bang, it is, ironically enough, this priest-astronomer who is credited with systematically articulating the concepts that underlie the theory, though the term Big Bang was not his coinage. The term was first used, in fact rather derisively, by another astronomer, Fred Hoyle (1915-2001), who—again, ironically enough—advocated a rival theory—the Steady State model, which theorizes that the universe has always been as it is.
Contrarily, the Big Bang theory contends that about 13.8 billion years ago what would become the universe was a very hot, very dense, compressed thing (if you could call it that)—a singularity, where all the rules of physics did not apply and time as we know it was non-existent. Literally in an instant (10-43 seconds), the universe began expanding, and in quick succession all four fundamental forces separated from each other, becoming distinct: gravity, the strong nuclear force, the weak nuclear force and electromagnetism, in that order. Expansion meant that all matter in the universe moved further apart, and the initially very hot conditions started to cool down.
The strong nuclear force enabled the smallest and primal constituents of matter, known as quarks, to coalesce to form protons and neutrons, which then formed the simplest atom—the hydrogen atom. In turn, hydrogen fused into helium and then more complex atoms. This process of nuclear fusion, which releases a lot of energy, produced our sun and continues to be the source of the sun’s energy. The dusty matter that was left over from the creation of the sun coalesced due to the attractive force of gravity to form our earth. The earth is part of a solar system that includes other planets and their moons, and the solar system itself is within the milky way galaxy.
Visible Light as Evidence of the Big Bang
The American astronomer Edwin Hubble showed that there were many other galaxies in the universe. He did this by observing the light emanating from matter in distant parts of the universe, which, critically, also allowed him to show that not only is the universe continuing to expand but also that the most distant parts of the universe are expanding the fastest. To be clear, the universe is not expanding into a void; rather, the universe is the void: It is self-contained, has no center, and looks the same from everywhere in space. We have a better sense of space itself and its relationship with time because of our understanding of the nature of light.
Going as far back as Galileo Galilei and, later, Ole Romer (1644-1710), visible light has been shown to have a very fast, but finite speed, which has been confirmed to be approximately 300,000 kilometers per second, and it is considered one of the constants of nature because it does not vary regardless of the speed of the observer. In 1666, Sir Isaac Newton (1642-1727) used a prism to break down white light into various colors, ranging from red to violet, but it would be many more years later before James Clerk Maxwell (1831-1879) showed that visible light is part of the electromagnetic spectrum, which, in order of increasing frequency and energy, and decreasing wavelength includes the following: radio waves, microwaves, infrared waves, visible light, ultraviolet light, x-rays and gamma rays. Scientific observations have detected cosmic microwaves that are a remnant of the Big Bang, but it is from visible light that we best get a sense of the expanding universe.
Albert Einstein (1879-1955) won the Nobel prize in physics in 1921 for showing in 1905 that light is carried by massless particles known as photons, and, therefore, light of a given frequency has photons of a given energy, which, according to blackbody radiation, is related to temperature and color. More energy means a higher frequency and shorter wavelength, and a shift from the red part to the violet part of the visible light spectrum. Thus, there is a relationship between frequency, energy, temperature and the color of light. We can distinguish the various colors that make up the visible light part of the electromagnetic spectrum based on their different frequencies. A body that glows red has the lowest frequency and longest wave length light, meaning the lowest energy and, therefore, temperature. One that glows violet has the highest frequency but shortest wave length light, meaning the highest energy and temperature.
Cosmologically, what this means is that light from an object in space moving away from the earth will have less energy when it reaches the earth than light from an object in space moving towards the earth. The light from the object moving away will have travelled a longer distance by the time it got to us, so much so that it will have less energy and will be akin to the frequency of the color red—it will be redshifted. Light from an object moving towards us will be blueshifted towards the violet part of the spectrum: It will have relatively more energy by the time it reached us than light from an object moving away from us. The redshifted light from now-distant parts of the universe started off at a finite speed of 300,000 kilometers per second when everything in the universe was closer together.
But as the universe expanded rapidly, the time taken for light to travel between different parts of the universe continued to increase because all matter was moving further apart, carried by the universe itself. Consequently, even though the age of the universe is 13.8 billion years, the light from the most distant parts of the observable universe could conceivably have travelled as much as 46 billion light years to a hypothetical central point in the universe, or 92 billion light years across the universe because of the expansion of the universe. Observing distant galaxies based on the light that reaches us from them is seeing them as they were in the past! Indeed, the light from the most distant parts of the universe, which are accelerating in expansion, will never reach us because the distance between the earth and these parts will continue to increase at a pace that exceeds the ability of their light to reach us. Other parts that are not too distant will become visible because their light will eventually reach us having travelled a very long time. As for our sun, if it stopped shining right now, we would only know it 8 minutes later because that is how long it takes the light from our sun to get to earth, which, as we will see in the next article, is very old indeed.
Unpacking the Big Bang Theory
This piece was the second in a two-part series. It was published on January 5 2019 in the Weekend Nation, a weekend newspaper published nationally in Malawi. It was published under the title “Unpacking the Big Bang Theory.”
The redshifted light from now-distant parts of the universe started off at a finite speed of 300,000 kilometers per second when everything in the universe was closer together. But as the universe expanded rapidly, the time taken for light to travel between different parts of the universe continued to increase because all matter was moving further apart, carried by the universe itself. Consequently, even though the age of the universe is 13.8 billion years, the light from the most distant parts of the observable universe could conceivably have travelled as much as 46 billion light years to a hypothetical central point in the universe, or 92 billion light years across the universe because of the expansion of the universe. Observing distant galaxies based on the light that reaches us from them is seeing them as they were in the past! Indeed, the light from the most distant parts of the universe, which are expanding at an accelerating speed, will never reach us because the distance between the earth and these parts will continue to increase at speeds that exceed the ability of their light to reach us. Parts that are not too distant will become visible because their light will eventually reach us, having travelled a very long time. As for our sun, if it stopped shining right now, we would only know it 8 minutes later because that is how long it takes the light from our sun to get to earth, which, as we will see, is billions of years old and not thousands of years old, as a literal reading of the Bible would lead one to believe.
The Age of the Earth
Literally substantively—that is, based on compositional material—the earth may be divided into three main layers from inside out: the core, the mantle, and the crust. Chronologically, however, the earth is divided into eons, eras, periods and epochs. It stands to reason that the earth may be dated from the inside out, much like the layers in, say, an onion or a cabbage. With respect to geologic (or deep) time, then, the oldest layers are the ones deepest in the core of the earth, and the youngest ones are the ones that make up the crust: this is relative dating, and it applies the law of superposition. Moreover, the principal of original horizontality holds that layers are usually deposited horizontally; thus, the more horizontal the layers the more confidence we can have that the layers are undisturbed. Relatedly, the law of succession of fossils essentially allows geologists working with paleontologists to determine the age of the layers of the earth based on the fossils within successive layers because, barring an event that transposes the layers, older fossils will be in the layers deeper in the earth.
Notably, geologic time does not assign actual numbers to the age of the earth, merely showing that one layer is older than the one above or younger than the one below. How then can we determine the actual age of the earth? How can we get the absolute date rather than the relative date? Thankfully, Antoine Henri Becquerel (1852-1908) lived on this earth, and in 1896, he discovered radioactivity. He was assisted in this endeavor by Pierre Currie (1859-1906) and Marie Currie (1867-1934), the only woman—and person, for that matter—to win the Nobel prize in both physics and chemistry. In their honor, radioactivity is measured in curies, and it is the decay of unstable isotopes of various elements. Isotopes are atoms of an element that have more neutrons than protons in their nucleus and are, thus, unstable. They must decay to a more stable, balanced state by giving off alpha particles (the nucleus of the helium atom), beta particles (electrons), positively charged electrons (positrons), gamma rays (when the nucleus has too much energy), or even neutrons. Critically, this process of radioactive decay occurs over specific time periods for various isotopes of elements, which allows for radiometric dating. For dating rocks on earth and other non-living materials, such as the fossilized remains of plants and animals, isotopes of elements such as uranium, thorium and potassium may be used because their half-lives range in the billions of years. Carbon is used for radiometric dating of living things that died relatively recently. Still, all radiometric dating is similar.
So, for instance, carbon exists as carbon-12 and carbon-14, which is radioactive, having two more neutrons than carbon-12. Everything that has ever lived before has had both carbon-12 and carbon-14 in it, with carbon-14 continually decaying and being replaced by more carbon-14 from the atmosphere of the earth, which is created by cosmic ray bombardment. Once a living thing dies, however, the carbon-14 is no longer replenished. It is therefore possible by looking at the amount of carbon-14 versus the amount of carbon-12 in the remains of living things to work backwards and estimate how long ago the thing died. The half-life of carbon-14 is 5730±40 years, and it decays into nitrogen-14. Assuming one had the remains of a living thing that consisted of a given amount of the carbon-14 isotope, it would take about 5,730±40 years for radioactive decay to occur enough to leave you, with half of the amount of carbon-14 you originally had. It would then take another 5730±40 years for the remaining amount to decay by half, and so on and so forth. If, for instance, the remains of a living thing have one quarter of the carbon-14 one would expect it to originally have had, one can work out how long ago the creature lived and died because the half-life of carbon-14 is known.
Isotopes of other elements are used pretty much in the same manner to date materials that are older than thousands of years because the precision of carbon-14 as an instrument for absolute dating does not extend beyond thousands of years. There is no reason to believe that the half-lives of carbon or other radioactive elements have changed, meaning we can be confident in our calculations of the age of the earth, fossils and the remains of living things using these elements. This concept is known as uniformitarianism, and was articulated by the father of geology, James Hutton (1726-1797) in his seminal Theory of the Earth (published in 1795): “The physical, chemical and biological laws that operate today also operated in the geologic past.” We must, therefore, look at the state of the earth at present to understand what it was like in the past. By using radiometric dating, it is possible to absolutely date the age of ancient creatures, trees and even the compositional material of the earth itself. It is from the fossils of these creatures and even more recently deceased ones that we get evidence for evolution.
The Origins of Life, Natural Selection and Evolution
Published in 1856, the Origins of the Species is Charles Darwin’s (1809-1882) magnum opus. In it he postulated that natural selection is the process whereby conditions in the natural environment make it so that only those living things with physiological features suited to that environment survive and, consequently, reproduce. Over time—indeed in most cases, a long time—as the surviving living things continue to reproduce, they will eventually develop physiological features that are quite different from their ancestors. With even more time, a new species will develop.
Before living things can be naturally selected to evolve, however, they must first exist. So how did life on earth begin? Believe me when I tell you that there are as many theories about how life on earth began as there are scientists, and I am only half joking. Whereas most scientists who study such matters generally agree that something akin to the Big Bang occurred billions of years ago, when it comes to the question of how life on earth began, there is much less agreement on the specifics. In other words, there is no single theory of the origins of life on earth.
Scientists generally agree that all living things have a common ancestor that came into being through some natural process billions of years ago when the earth was still very young; it is now about 4.6 billion years old. Some scientists contend that matter from elsewhere in the cosmos must have deposited organic material on earth (panspermia theory), but others contend that life on earth came about spontaneously given the right chemical and environmental conditions (spontaneous origin). This spontaneous origin may have occurred near the edge of oceans, in the earth’s crust, in clay, or in vents deep in the sea. Because of the rather dreary conditions of the early earth, only the simplest organisms, prokaryotes, had the physiological features to survive, and their existence has been discovered because these prokaryotes formed layers of rocks knowns as stromatolites, which have been dated to between 3.5 and 3.9 billion years ago during the Precambrian era (4.6 billion years ago to 542 million years ago). From this simple and rather inauspicious beginning, living things evolved into ever more complex beings.
During the Paleozoic era, between 542-251 million years ago, you had the emergence of many water-dwelling creatures and some vascular plants. The Mesozoic era, 251-65.5 million years ago, saw the emergence of cone-bearing plants and, during the Jurassic era, dinosaurs. Throughout the millions of years, various extinctions occurred killing off formerly existing life forms and allowing new life forms to emerge. One such extinction occurred 65 million years ago when a large asteroid or comet came hurtling down to earth creating the Chicxulub crater underneath the Yucatan peninsula in Mexico, Central America. So great was the impact, it killed off about 75 percent of life on earth, including the dinosaurs. This was good for us because it ushered in the Cenozoic era, with its diversity of creatures including Homo Sapiens (wise man). Charles Darwin conjectured in the Descent of Man (published in 1871), that Africa was the original home or our ancestors, and he was right.
We started evolving in Africa from hominids some 7 million years ago. Our ancestors included Homo habilis (handy man) and Homo erectus (upright man). (And, no! Hominids are not the same as monkeys—just, to be clear. But both hominids and monkeys are primates.) Our ancestors lived by hunting using tools they had fabricated from stone and other materials in the environment. By 100,000 BCE our anatomical evolution was complete: We could walk upright; we could speak because our voice boxes are lower in our necks than they are in other creatures; we had opposable thumbs that could form intricate objects; we had non-honing chewing capacity, and, critically, we had big brains, which made us intelligent enough to exploit the resources in whichever environment we found ourselves.
Indeed, we now find ourselves in all sorts of environments. An ice age from 2 million years ago to 9,000 BC ensured that the continents were connected by ice, allowing our ancestors to literally walk out of Africa to the rest of the world, reaching all the continents by 18,000 BC. Our differences in skin complexion are the result of living in various environments, which necessitate that we either absorb more sun or less sun. So, for example, consider the complexion of President Salva Kir of South Sudan, where the sun glares, and then consider the complexion of President Vladimir Putin of Russia where the sun nary shines. Enough said!
For all the controversy surrounding the Big Bang and evolution, and the Biblical version of creation, what impresses me are not the differences between the two versions but the similarities. First, there was a light, then the creation of creatures, starting with those in the waters, then eventually man came about, God’s proudest creation, or, as the scientists would say, the most highly evolved creature. The Biblical and scientific versions of how the universe and the world came about are, to my mind, effectively different ways of telling the same story.
I have no reason to doubt the scientists: they have given us cars and airplanes and all the other things that make modern life possible. They know their stuff. However, even the scientists cannot tell us where the Big Bang itself came from. Their lack of clarity on how life originated on earth speaks to the limits of science in explaining natural phenomenon. Moreover, evolution does not seem to account for the existence of an actual Adam and Eve, who are the central characters of Genesis in the Bible. Still, setting aside the matter of whether it was literally six twenty-four-hour days or billions of years, it seems to me both versions are believable in that they tell the story of how a powerful creative force brought everything into being. Or maybe I am just corrupt!