God, the expanding universe, and dark energy

J asks:

1.  Could you convert the rate of expansion of the universe in everyday terms?  As an automotive engineer, I am very comfortable with units of ft or miles per second squared

2.  How much energy from God is infused into the universe every second in order to maintain the space energy density.

When I initially set out to answer J’s questions, I was just going to write a line or two giving the numerical answer for each one. But what fun is that? Instead, I decided to take you all down the rabbit hole with me, and get into the details of each of these questions. But if you just want to skip ahead to the answers, they’re highlighted at the end of each discussion.

Here we go…

1. First, a bit of context. In 1929, American astronomer Edwin Hubble presented evidence that galaxies are rushing away from one another, and that the speed with which they are rushing away is proportional to their redshift. This is interpreted to mean that the further away galaxies are, the faster they appear to be moving away, and this was the first physical evidence that our universe was not static and eternal, but dynamic and finite in time. The average rate at which galaxies are moving away from each other — called the Hubble constant — is a reasonable measure of the expansion rate of the universe, so we’ll use that to answer J’s question. The Hubble constant is about 70 km/s per megaparsec of space.

Now, I could just throw that number at you and convert the units to something more relatable and be done with it, but why do that when we have an opportunity to go into some nifty astronomical stuff? For instance, did you know astronomers don’t use light-years in their work? Light-years are used more for relating astronomical stuff to the general public. Instead, astronomers use parsecs, where one parsec equals 3.26 light-years. It may seem arbitrary, but there’s a sensible reason astronomers use this seemingly weird unit for distance. The answer lies in the definition of the word ‘parsec,’ which comes from ‘parallax’ and ‘arcsecond.’ Parallax is the apparent shifting of something in the foreground with respect to a very distant background. You can observe parallax by holding out your thumb and then observing it shift relative to stuff further away as you close one eye and then the other. This happens because your eyes are separated by a short distance. If you were able to adjust the distance between your eyes, you would notice more parallax the further apart you moved your eyes.


Based on the same principle, we observe parallax of nearby stars relative to much further stars as the Earth orbits around the Sun. When the Earth is on one side of the Sun, we can observe a nearby star relative to a particular background of stars. Six months later, when the Earth is on the other side of the Sun, we observe the same star relative to a different background of stars. This is rather useful in terms of measuring distances, because the further away something is, the less parallax you observe. And that leads to the definition of parsec: a parsec is the distance at which you would observe exactly 1 arcsecond of parallax as the Earth goes around the Sun.


And now I’ve introduced another term that needs to be explained. An arcsecond is a unit of angular size. When we look at objects and assess how large they are, we aren’t actually measuring linear sizes, but rather how big of an angle they subtend. The Moon in the sky, for instance, subtends a half a degree of ‘arc.’ That’s its size as far as our eyes and brains can measure it. If we have some idea of how far away it is, then our brains can translate that to a linear size. (Angular size + knowledge of distance + a bit of cogitation = “Wow, half a degree of arc and that thing is 240,000 miles away? It must be big!”) So then, what’s an arcsecond? Well, one degree of arc is divided up into 60 arcminutes, and each arcminute is divided up into 60 arcseconds. So, an arcsecond is 1/3600th of a degree, which seems awfully small until you realize that the smallest angle we can measure in astronomy is about one thousandth of that.

Let’s return to J’s question. We know the Hubble constant is about 70 km/s per megaparsec of space. Mega means million, so for every million parsecs of distance away from the Milky Way, space is observed to be expanding at a rate of 70 km/s. In more relatable terms, that translates to about 157,000 mph per 3.26 million light-years of space. More distant galaxies are seen to move faster simply because of their distance. I have my students do a little experiment to help visualize this. Take a thick rubber band, cut it and lay it out flat, and then draw some dots on it: one dot in the middle to represent the Milky Way, and then dots on the other side at various distances to represent other galaxies. As you stretch out the rubber band, the “rate” at which the other dots move from the MW dot depends on how far away they are, and the more distant ones do indeed expand faster than the closer ones.

A better way to get an idea of how fast the universe is expanding is to think of scale instead of proper distances. The scale is a rough guide to the distances between galaxies, which grows as the universe expands, but we don’t attach any units to it. Instead, we think about how long it takes the scale to double or triple or increase by a factor of 100 or whatever. Billions of years ago, when the universe was small in scale, it was doubling in scale very rapidly, but as the scale got much larger, it took longer and longer to double. The last time the universe doubled in scale, it took about 7 billion years. The next doubling will take much longer. Incidentally, this is the basis for reconciling a literal interpretation of Genesis 1 with a very old universe, as shown here. This is complicated a bit by the observation that the universe is accelerating in its expansion, and this leads to J’s next question.

Summary: The universe is expanding at a rate of about 157,000 mph per 3.26 million light-years of space.

2. Astrophysicists have proposed the existence of some mysterious, unseen form of energy in the universe to account for the speeding up of its expansion. They call this energy “dark energy,” and it has the peculiar property that its space density stays constant. Density is the amount of something per volume, so this means the amount of dark energy per volume of space never changes, even though the amount of space in the universe is increasing every moment. Think about how weird that is. That means the extra dark energy needed to keep the dark energy per volume constant as the universe expands has to come from somewhere. But where? I recently lectured about this to a group of Christians who were keen on science, and explained that this is consistent with scripture in which we are told that God sustains the universe (Heb 1:3, Col 1:17). When J heard this, he wanted to know how much energy per second God is injecting into the universe to maintain the constant dark energy density. So, let’s try to figure it out.

Even though dark energy is the dominant “stuff” of the universe, it’s extremely rarefied. It makes up 68% of the total of everything that’s in the universe, and yet its energy density is a paltry 10-9 joules for every cubic meter of space. The reason dark energy dominates the universe in spite of its low energy density is that space is HUGE — there’s an astronomical amount of cubic meters in space, so that paltry energy adds up to something big over large distances.

It turns out, we can’t answer J’s question directly, since we don’t know the total size of the universe. The universe could be finitely huge or infinitely huge; we simply don’t know. But we can estimate the amount of extra energy needed per second per megaparsec of space and use that to estimate how much extra energy is needed for the amount of the universe we can observe.

Remember that the Hubble constant, 70 km/s per megaparsec, tells us the rate of expansion. So, let’s first imagine a cubic chunk of space that’s a million parsecs on each side. Converting to more convenient units, this cosmic cube is 3.09 x 1022 meters on each side. This chunk of space is expanding at a rate of 70 km/s, which is 70,000 meters every second; this means every second, the chunk of space is gaining (3.09 x 1022 m + 70,000 m)3 – (3.09 x 1022 m)3, or 2 x 1050 cubic meters, in volume. If the space density of dark energy is 10-9 joules for every cubic meter, then each cubic megaparsec chunk of space is gaining an extra 2 x 1041 joules per second.

Let’s put that in relatable terms. One joule per second is known as a watt, a common household unit of power that you probably recognize from lightbulbs. So, let’s think of the extra energy injected into space every second in terms of watts. The Palo Verde nuclear power plant in Arizona has three reactors with a total power output of about 4,000 megawatts. If we take 2 x 1041 watts and divide by that, we get 5 x 1031 nuclear power plants-worth of power for each of these million-parsec chunks of space. That’s a 5 with 31 zeroes after it. Sounds impressive, doesn’t it? Well, consider that the size of the observable universe is much larger than this hypothetical chunk of space, about 30 gigaparsecs in any direction, which means that that the total amount of energy per second added to the observable universe is equivalent to 1045 nuclear power plants. To complicate things a bit, this is the momentary increase in energy per second of the observable universe, since the universe is expanding every moment. And, oddly, this is kind of wimpy when you consider that the theoretical prediction for the space density of dark energy is about 30 orders of magnitude higher than what’s been measured, a mismatch that so far no one knows how to resolve.

Summary: The amount of energy that’s currently added to the observable universe per second to maintain a constant space density of dark energy is the equivalent output of 5 x 1045 nuclear power plants. That’s a billion-trillion-trillion-trillion nuclear plants.

I know I skipped over some stuff that probably has you scratching your head, like the idea that some mysterious form of unseen energy is pouring into our universe every second from who-knows-where and that God has something to do with it. This dark side of the universe, which includes another substance called dark matter, is a fascinating topic that, believe it or not, relates to Christian scripture. If this interests you, stay tuned. I’m in the process of writing a booklet on the topic, and plan to host an online seminar through my publisher sometime in the next year.

Weekly Psalm 19: The Heart of Cygnus

Here is your weekly reminder of Psalm 19 — the heart of Cygnus.


Also known as IC 1318 or the Sadr region, this nebula lies at the heart of Cygnus the Swan, a summer constellation in the Northern hemisphere. IC 1318 is an emission nebula, ionized by the radiation from a nearby hot star.

The bright star on the left is Deneb (Alpha Cygni) and the bright star on the right is Sadr (Gamma Cygni), neither of which are actually part of the nebula, but lie partway between Earth and IC 1318. These stars are clearly visible to the naked eye, but the emission nebula is too faint to be seen without long exposures on a telescope.

The pink patches are ionized hydrogen gas, and the dark streaks are dust-infused gas blocking visible light from view.

Image credit:Bill Mark.

Backyard Astronomy: August 2016


Here are some fun astronomical events you and your family can enjoy in the month of August. All you need is an inexpensive telescope or binoculars for most of these events, but some of them are viewable with the naked eye.

August 12-13: Perseids Meteor Shower. Meteor showers occur when the Earth moves through a cloud of debris left behind by a comet. The Perseids are debris from Comet Swift-Tuttle. As meteor showers go, this one is top-notch, producing many bright streaks and up to 60 meteors per hour at its peak. The shower runs every year from July 17th to August 24th, but will peak on the night of the 12th and the early morning of the 13th. Look in the direction of the constellation Perseus after midnight for your best chance.

August 16: Mercury at Greatest Eastern Elongation. Mercury will be at its greatest apparent distance (~27 degrees) from the Sun in the sky. It can be a little tricky to observe tiny Mercury as it follows the setting Sun on the Western horizon. The closer you are to the equator, the higher Mercury will be in the sky before it descends, and the easier it will be to see it.

August 27: Conjunction of Jupiter and Venus. You don’t want to miss this one. A conjunction occurs when two or more planets appear to overlap or come very close together in the sky. (Remember, in terms of their physical separations, these planets are still very far away from each other.) This conjunction will take place just after sunset, when Jupiter and Venus will appear less than a tenth of a degree away of each other on the sky. That’s super-close!

Weekly Psalm 19: Bode and the Cigar

Here is your weekly reminder of Psalm 19 — the galaxy pair, M81 and M82.


This galaxy pair is part of the M81 group, a collection of 34 galaxies that are all gravitationally bound to each other. These two galaxies (click the image to enlarge it) are particularly strongly attracted to each other, which has triggered some extreme activity in both.

The spiral galaxy on the left is M81, and is also referred to as Bode’s Galaxy, after J.E. Bode, who discovered it in the 18th century. Bode’s Galaxy has an active black hole in its center weighing in at 70 million times the mass of the Sun. The gigantic black hole is feeding on gaseous material that has spiraled down to the center of the galaxy, which causes it to shine very brightly. The galaxy on the right is M82, and is sometimes called the Cigar Galaxy because of its cigar-like shape, which is due to its gravitational interaction with M81. This interaction has triggered massive star formation in M82.

The galaxy pair appears in the Ursa Major constellation, and is relatively nearby at 12 million light-years away, making it a favorite of both professional and amateur astronomers. The M81 Group is a neighbor to the Local Group, which contains the Milky Way, and the two groups are part of the much larger Virgo Supercluster of galaxies.

Image credit:Anttler.

Weekly Psalm 19: Spiral galaxy NGC 2841

Here is your weekly reminder of Psalm 19 — spiral galaxy NGC 2841.


Click on the image to appreciate its full grandeur.

Such a boring name for such a beautiful object. German-British astronomer William Herschel discovered NGC 2841 in the late 18th century, although at that time he wouldn’t have known what he was looking at. Astronomers at the time categorized these indistinct objects as “spiral nebulae” and thought they resided inside of the Milky Way. By the 1920s, astronomers realized they were looking at “island universes,” what we now refer to as galaxies, that are well beyond the Milky Way.

NGC 2841 is, like our galactic home, a spiral galaxy. However, it’s about 50% larger and its arms are “flocculent” or patchy and more tightly wound than the Milky Way’s. At 46 million light-years away, this galaxy is close enough to us that the Hubble Space Telescope was able to snap this magnificent view of its interior. Its golden-yellow nucleus contains a dense population of very old stars, while its arms are punctuated by bright blue dots and glowing pink hydrogen clouds indicating regions where new stars are forming. The dark swirls in the galaxy’s patchy arms are comprised of dusty gas that blocks visible light from view. If you have sufficiently dark skies and a large-ish telescope, you should be able to see this galaxy as an indistinct patch of fuzz in the Ursa Major constellation.

Image credit: NASA, ESA, and the Hubble Heritage (STScI / AURA) – ESA / Hubble Collaboration.

The grand ballroom of the universe

There are a lot of galaxies in the universe, and like people on a crowded dance floor, they sometimes collide. The time it takes for the full collision to unfold is hundreds of millions of years, so what we see when we observe colliding galaxies with our telescopes are really just snapshots of particular moments during the collision. To try to understand the physics of galaxy collisions, astrophysicists often create sophisticated supercomputer simulations that match our observations of different stages of actual collisions; but instead of taking a hundred million years to play out, we can watch the whole thing happen in the space of minutes.

I love watching simulated galaxy collisions, and I think you’ll find them fascinating, too. It’s as though two galaxies decide to become partners in some cosmic ballroom dance. Even though the collisions are destructive, there is something so graceful and elegant about them that I always hear Mozart in my head as I’m watching.

I wanted my astronomy students to appreciate all this, so a few years ago I put together a video compilation of three galaxy collision simulations by astrophysicists at Case Western Reserve University and set them to one of my favorite Mozart symphonies. The simulations are sometimes paused mid-collision so that the “camera” can pan around to give us a look from different angles. Following each simulation there’s an image of an actual galaxy collision of that type so you can see how well the physics of the simulations matches what we observe in the universe.


Weekly Psalm 19: The Bubble Nebula II

I’ve had requests to bring this feature back, which I am happy to do. So, here is your weekly reminder of Psalm 19 — the Bubble Nebula, up close and personal.


Click on the image to fully appreciate its grandeur.

The Bubble Nebula is a shell of gas surrounding a massive, extremely hot star that is 15 times the size and 40 times the mass of our Sun. Stellar winds from the star push the bubble of gas out, while radiation from the star excites the gas in the bubble and causes it to glow.

The nebula resides in a giant molecular gas cloud in the constellation Cassiopeia, and is about 7,100 light-years away. The Bubble itself is 3 – 5 light-years in size, which, if you could see it with your naked eye, is half the apparent size of the full Moon on the sky.

This image is a composite of images of the Bubble Nebula taken with the Hubble Space Telescope this year, created by NASA to commemorate the 26th anniversary of Hubble’s launch. The nebula is imaged separately with different filters, and then combined with false colors to create this compelling final product. What you’re seeing here is radiation from excited hydrogen (red), oxygen (green), and sulfur (deep red) atoms.

Image credit: NASA, ESA, Hubble Heritage Team (STScI / AURA)

Online Astronomy Course

I am pleased to announce that I will be teaching an online astronomy course through Castalia House, likely this coming fall. This will be a 12-week course that surveys important topics in astronomy, including the philosophy of science, some history of astronomy, the night sky, seasons, moon phases, eclipses, atoms and spectra, the solar system, stars and stellar remnants, observational astronomy, galaxies, the big bang, the fate of the universe, and multiverses, string theory, and other controversies in cosmology.

This is a modern science course taught by a credentialed astrophysicist, and includes both historical perspective and cutting edge science. If you are fascinated by the night sky, and want to learn more about nature’s grand spectacle, this is the course for you. There is no prerequisite, and the course will be mostly at the conceptual level, but students may find that a bit of rudimentary algebra is helpful.

The format of the course is a weekly 90 minute video lecture followed by optional Q&A, reading assignments and night sky exercises (no telescope required), and periodic quizzes to assess your understanding. The course will be offered on a graded, pass/fail, or audit basis. Students who successfully take the course graded or pass/fail will receive a certificate of completion.

If there’s interest, future courses could include: introductory conceptual physics, modern conceptual physics (relativity, quantum mechanics, nuclear and particle physics), and the Bible and science.

A brief biographical sketch of the professor: I received a B.A. in physics (minor in mathematics) from Eastern Oregon University, and an M.A. and Ph.D. in astrophysics from the University of Texas at Austin. I am currently a research scientist at a major research institution, where I study nature’s most extreme objects: quasars and supermassive black holes. I am also a visiting professor of physics at a liberal arts university, where I have taught astronomy and physics for several years. I am a devoted Christian who was inspired to convert from atheism to Christianity through my scientific work, and continue to find inspiration in the convergence of Christian belief and modern science.

Reflections on physics and Christian faith


The following is a guest post by Dr. Kelly Cline, who is both a friend and colleague of Dr. Salviander. Originally from Homer, Alaska, Dr. Cline studied physics at Eastern Oregon University, before earning his Ph.D. in astrophysics from the University of Colorado at Boulder in 2003.  He is currently an associate professor of mathematics and astronomy at Carroll College in Helena, Montana, where he lives with his wife and four children.

“All things came to be through him, and without him nothing came to be…” John 1:3.

When the actor Gary Oldman was preparing to play Beethoven in the film Immortal Beloved, he asked the director to recommend biographies to read. The director replied: “…there is only one he should consider: the music. This music is an unvarnished, uncensored record of Ludwig van Beethoven’s passions, fears, violent anger, humanity and, finally, victory over unimaginable adversity. It is a direct link to his state of mind.”

In works of art created by the human hand, there is powerful connection between the creator and the created. The symphonies of Beethoven, the paintings of Raphael, and the plays of Shakespeare tell us something very deep about the artists who created them.

In this spirit, there is a very old tradition, going back at least to Galileo of asking the question: What does the scientific study of the basic physical laws of the universe tell us about its Creator? What can physics tell us about God?

Physics is the most fundamental of the natural sciences. The principles of chemistry can be understood as applications of the physical laws of electromagnetism and quantum mechanics. Biology and geology can be understood as applications of chemistry and physics. But in physics we seek to understand the most elemental principles of the physical universe, the deepest laws which govern all physical motion in our universe.

Today we know more about the nature of our physical universe than at any time in history. Of course our knowledge of the laws of physics remains incomplete and imperfect. Yet, we have learned an enormous amount about our universe and its laws since the days of Isaac Newton, and currently our theories at least provide a remarkably powerful and accurate approximation to the laws of physics under a wide range of conditions.

For reasons, such as the incompleteness of our knowledge, it is not simple to see a clear and obvious picture of the Creator painted in the equations of physics. However, as we immerse ourselves in this science, I think that we can see certain striking points of resonance between the Creator that we come to know through science and the Creator that we come to know through scripture. In this essay we will consider (1) the role the unification in the development of physics, (2) the apparently paradoxical discoveries of relativity and quantum mechanics, (3) the discovery of the big bang event, the moment of creation, and (4) the unchanging and universal nature of physical law which has led to the development of the world we know. Perhaps these points of resonance may give us some insight into the Author of all things.

Unity and Unification in Physics

Hear, O Israel! The LORD is our God, the LORD alone! Deuteronomy 6:4

Physics begins with the study of motion and its causes. The first person we know who wrote seriously about why things move was the ancient Greek philosopher Aristotle. In approximately 350 B.C., Aristotle examined the world and saw different types of motion in different places. Here on Earth he saw stones fall to the ground, while smoke and flames flickered upward, but in the heavens he saw the moon and planets move in what looked like perfect circles. So, Aristotle proposed that different things move in different ways according to different rules. Aristotle argued that here on Earth all things are made of four basic elements, earth, air, fire and water, and that these seek their natural level in the universe, with the force of gravity causing heavy objects to sink, while the force of levity caused light objects to rise. But Aristotle said that objects in the heavens must be made of a different substance, which he called aether, and Aristotle said that elements composed of this aether must naturally move in circles. Aristotle’s solution to seeing different objects move in different ways was essentially to divide the universe into different realms, composed of different substances, which followed different rules.

Almost two-thousand years later, Isaac Newton finally brought the universe back together again. Perhaps inspired by his deep faith in one God, one hand which shaped every part of the universe, in 1687 Newton published his law of universal gravitation, a precise mathematical theory which explained both the falling of a stone and the orbit of the moon. Newton unified two very different types of motion, showing that they are both a consequence of one universal force of gravity. To Newton, gravity was a force pulling each pair of masses in the universe directly towards each other. So if the Earth pulls the moon straight toward it, why does the moon move in an orbit around the Earth? Using the newly developed calculus, Newton showed that because the moon is in motion, the force of gravity from the Earth bends the moon’s path creating the elliptical orbit that we observe.

Newton took two apparently disparate types of motion and showed that they could be explained as manifestations of one deep underlying principle, the first of several great unifications that have shaped the development of physics.

For you are great and do wondrous deeds; and you alone are God. Psalm 86:10

In the 1700s, the electric force and the magnetic force appeared to be completely unrelated forces. The magnetic force is what attracts and repels magnets from each other, and causes magnets to stick to refrigerators. The electric force is what pulls around electric charges, causing a balloon to stick to wall after you charge it up by rubbing it on your hair. But there does not appear to be any special force between a charged balloon and a refrigerator magnet.

Then, in 1820, while giving a lecture at the University of Copenhagen, the Danish physicist Hans Christian Orsted discovered that an electric current – moving charges – produced a magnetic field and could move a compass needle. Magnets and charges don’t appear to interact when they are at rest. But when charges are in motion, Orsted showed that they can exert a magnetic force. This quickly inspired other physicists to see if the it could work the other way.

In 1831, the English physicist Michael Faraday showed that a moving magnet can create electric forces which can cause the charges in a metal to move, creating an electric current. This is the basic process that causes our electric generators to operate: Spinning magnets create the currents that light our world!

In 1862, this experimental work was finally brought together mathematically by the Scottish physicist, James Clerk Maxwell. Maxwell proposed that electric and magnetic forces were different aspects of one fundamental phenomenon. With one set of equations he unified all that had been done before, and created a theory that made some startling new predictions. Studying these equations, Maxwell discovered that electric and magnetic fields could move together through empty space. A changing electric field could create a changing magnetic field which would in turn create a changing electric field again, in a complete cycle, so that energy could be carried through space as electromagnetic waves. Maxwell calculated that these electromagnetic waves would travel at an enormous speed of about 186,000 miles per second, a speed which closely matched the measured speed of light: Maxwell became the first human in history to understand that light itself is an electromagnetic wave. Even more powerfully the unification of electric and magnetic forces opened up the possibility of other types of electromagnetic waves, and so in 1887 Heinrich Hertz published the first of a series of experiments demonstrating the existence of radio waves.

This great discovery that electric and magnetic forces are the result of a single more fundamental force has shaped our world where we constantly use electromagnetic waves for radio and television transmissions, cellphones, and wireless computer connections.

…one God and Father of all, who is over all and through all and in all. Ephesians 4:6

The 20th century saw the discovery of two new fundamental forces which both seemed completely disconnected from gravity and electromagnetism. Physicists discovered that atoms contain nuclei where positively charged protons and neutrally charged neutrons are packed into a remarkably tiny volume. Positive charges repel each other with a force that gets stronger when the charges move closer together. So the electric force pushing these protons away from each other must be enormous. Binding these protons so closely must require another force, a fantastically strong force to overwhelm this electrical repulsion and hold the nucleus of an atom together. As a result, physicists dubbed this new force, “the strong nuclear force.”

As physicists probe more deeply into the mysteries of the atom, some unusual types of radiation indicated the existence of yet another force which could cause a neutron to transform into a proton and other particles. This force was dubbed the weak nuclear force. Thus by the mid-20th century, it appeared that our universe was regulated by the action of four distinct forces: gravitation, electromagnetism, the strong nuclear force, and the weak nuclear force.

However, in 1968, Sheldon Glashow, Abdus Salam and Steven Weinberg proposed a startling new theory. Relying on deep mathematical symmetries, they proposed that electromagnetism and the weak nuclear force were both very different manifestations of a single more fundamental electroweak force. Superficially these two forces could not possibly be more different. The weak nuclear force transforms particles and is so short range that it only works inside the nucleus of an atom, while electromagnetic waves can extend so far that they allow us to see the stars. Yet, a profound

mathematical resonance between these two forces led Glashow, Salam, and Weinberg to propose their remarkable theory, and from this theory they predicted the existence of a completely new particle, the Z boson. When the Z boson was discovered at the CERN laboratory in 1983, the physics world celebrated this amazing triumph. Once again, physicists had discovered that two apparently different phenomena could be unified with a single more fundamental theory.

For there is one God. There is also one mediator between God and the human race, Christ Jesus, himself human, I Timothy 2:5

Again and again, physicists have discovered deeper and deeper unifications in the fundamental laws of our universe. The more closely we look, the more we discover an essential unity in all things. Today physicists are working hard to unify the known laws of physics even further, with “grand unification theories” that integrate the strong nuclear force with electroweak theory, and even more ambitious ideas like “string theory” and “loop quantum gravity” that bring gravity too into the same system of equations.

The Apparent Paradoxes of Relativity and Quantum Mechanics

For my thoughts are not your thoughts, nor are your ways my ways… Isaiah 55:8

The dawn of the 20th century saw an enormous crisis, as physicists were forced to grapple with new phenomena were so strange that they appeared to be paradoxical.

Consider this experimental fact: Every beam of light will always be measured to travel at the same speed, 300,000 kilometers per second, no matter how the emitter of the light is moving or how the receiver of the light is moving. Imagine that you are in a spaceship and someone in another spaceship flashes a beam of light toward you. When you measure the speed of that approaching beam of light, you will get the same speed whether your friend’s ship is flying towards you or away from you. If you were to turn on your own rocket engines and fly directly toward that oncoming beam of light, you would expect to measure that the beam of light would be traveling faster, relative to you. If you were to turn on your rocket engines and fly directly away from that oncoming beam of light, you would expect to measure that the beam of light would be traveling slower, relative to you. Yet, careful measurements make this matter clear: All observers always measures every beam of light as traveling at the exact same speed, no matter how they move relative to the beam of light. This strange fact was first indicated in 1887 by the Michelson–Morley experiment performed at what is now Case Western Reserve University in Cleveland, Ohio. Over the past century this reality has been confirmed in numerous experiments, and is used every day by our modern GPS system. In order to accurately pinpoint a location on the surface of the Earth using radio waves from moving satellites, the system must account for the fact that the speed of light is constant, no matter how the satellites are moving.

This bizarre reality seems contradictory. It appears to defy our most fundamental definitions of what speed and motion are all about. Yet, in 1905, Albert Einstein showed that there is a logic to this strange phenomenon. Just because something defies our intuition and contradicts our expectation does not mean it is irrational. Einstein showed that this is only a paradox if we assume that time and length

are universal constants. Speed is what we calculate when we take a distance traveled and divide this by the travel time to get miles per hour, meters per second, or some other measure of speed. If time and distance are the same for all observers, then all speeds must be relative and depend on the motion of the observer. To cause all observers to measure the same speed of light, no matter how they move, different observers must disagree about time and length. The time between two events might be one second for me, two seconds for you, and half a second for someone else, if we are all moving differently.

Einstein’s theory of relativity was a startling revelation to the physics community, but it won the day because although it confounds common sense, it is logically consistent, and it accurately explains the experimental data. But just as this revolution was winning acceptance, an even stranger and more disturbing theory was in its infancy, which would soon shatter our common sense more profoundly.

In order to unlock the secrets of the atom and explain the actions of individual electrons required an entirely new way of thinking. Electrons are bound to the nucleus of an atom by the electric force, because their negative charge is attracted to the positive charge of the protons in the nucleus. So early models of the atom proposed that electrons orbited around the nucleus due to the electric force in the same way that planets orbit around the Sun due to the gravitational force. However, this simple model didn’t explain the strange behavior of electrons, sending physicists back to the drawing board. You see, a planet can orbit around the Sun at any distance, depending on how much energy it has. The more mechanical energy a planet contains, the farther away from the sun it will orbit. However, experiments quickly demonstrated that inside an atom, electrons could only orbit at certain specific distance away from the nucleus. Why would that be? To explain this odd behavior required physicists to completely reimagine the nature of an electron.

Rather than thinking of electrons as being particles orbiting a nucleus, like planets orbiting the sun, in 1924 the French physicist Louis de Broglie proposed that electrons are more like musical notes resonating in an instrument, like a trumpet. Louis de Broglie proposed that electrons act like waves. Consider this: the length of a trumpet tube controls the notes that can be played. For a given tube length, there is a specific set of notes that can be played on the trumpet, which fit different numbers of wavelengths into the tube. There is a lowest possible note that the trumpeter can play, then by putting more energy into the lips the trumpeter can play a note an octave higher, but the trumpeter cannot play any notes between these two, because these would not resonate within that length of tube. The theory of waves explains a certain length of trumpet tube can only play a certain set of notes, and in exactly the same way, Louis de Broglie’s theory explained why electrons can only orbit at certain distances away from the nucleus. He showed that an electron will sometimes behave like a particle, a tiny point with one specific location, and sometimes like a wave which can spread out and fill an enormous volume, in the same way that the sound wave from a trumpet can fill a room. If you fire an electron at a screen, first it spreads out like a wave, but when it hits the screen, it turns back into a particle and we see its flash of energy at one specific point on the screen.

But here’s the crux of the problem: When the electron transforms from a big spread-out wave into a single point particle, exactly where will this point be? How does our universe decide exactly where within the broad electron-wave we will see that single flash of electron energy? The answer

shook the physics community to its foundations: It’s random. It happens by chance. When the electron wave hits the screen, the universe picks the electron’s location in a completely unpredictable way. The quantum theory describes a precise distribution of randomness, which can be tested by using enormous numbers of electrons in our experiments, but the location of each individual electron cannot be predicted. The quantum theory says that randomness is woven into the very fabric of our universe at the deepest level. This contradicted physicists’ common sense about what a theory of physics was supposed to say. Einstein himself was so dismayed by this bizarre discovery that he refused to believe it, saying, “God does not play dice!” He spent the rest of his life trying to find another theory which would explain the strange behavior of electrons without the distasteful random factor.

Almost a century later the quantum theory has survived every experimental test with flying colors. After decades of looking for other alternatives the physics community has been forced to accept that randomness is an essential part of the laws of our universe. Even though it contradicts our common sense about what a law of physics should be, the quantum theory works. Initially it appears strange and irrational, but as we study it, we realize that there is a logic to it. The quantum theory is a rational system, even though it is alien to our common sense.

How often do the scriptures tell us that God’s ways are not our ways? Consider the parable of the vineyard (Matthew 20:1-16). Defying all expectations of common sense, the owner of the vineyard chooses to pay all the workers equally, no matter how many or how few hours they worked. Although it violates the common sense of the workers, the owner has his own system for choosing how he will distribute his rewards.

The Big Bang: Echoes of Genesis

In the beginning, when God created the heavens and the earth, the earth was a formless wasteland, and darkness covered the abyss, while a mighty wind swept over the waters. Then God said, “Let there be light,” and there was light. Genesis 1:1-4

A century ago, most scholars in Europe and America thought that our universe had always been here. They thought our universe was infinitely old, that it had no beginning, and that our universe was static, eternal, and essentially unchanging. When Albert Einstein was developing his general theory of relativity, his new theory of gravity, he was quite disturbed to discover that his equations indicated that the universe as a whole should be changing, expanding, contracting, or evolving in some way. Even if all the galaxies of the universe were at rest for one moment, then gravity should then pull them all together, causing the universe to contract over time. Einstein was certain that the universe was unchanging, and so in 1917 he a term to his equations which he called a “cosmological constant,” a pressure from empty space which could oppose the attraction of gravity, and cause the universe to stand still.

Then, in 1927 a young Roman Catholic priest and scientist, Father Georges Lemaître began using Einstein’s equations of gravity to create a revolutionary new theory that we now call “the big bang theory.” In 1931 he proposed that our universe had a beginning, a point in which time itself began.

Einstein was initially very skeptical of this new theory, saying “Your calculations are correct, but your physics is atrocious.” Einstein was concerned that this priest was being inspired more by the book of Genesis than by hard-nosed science.

While Lemaître was doing his theoretical work, the astronomer Edwin Hubble pointed his telescope out at distant galaxies and discovered that our universe is expanding: Galaxies are spreading out through space, getting farther and farther from each other. This means that tomorrow, galaxies will all be a little farther apart and yesterday they were a little closer together. The farther we look into the past, the closer galaxies must have been, until we reach a time when all the galaxies must have been compressed together. At the current rate of expansion, all the galaxies in the universe must have all squeezed together at a time about 14 billion years ago.

Using Einstein’s equations of space and time, Lemaître and others created a theory, a set of mathematical equations, which explains the expansion of the universe we see today. The theory says that the universe began in an instant, when all of space everywhere was filled with hot, dense energy under high pressure. The fires of the big bang equally filled every point in the entire universe. This energy caused space itself to stretch and expand, and as the universe expanded, the energy was smeared out across an ever expanding volume, and so it cooled, turning into first the atoms of hydrogen and helium gas. The momentum of this initial expansion causes the universe to go on expanding to this day.

How can we be sure that this event actually took place? No one was around 14 billion years ago to observe the big bang. However, we can use the big bang equations to make a series of specific predictions about things we can see today. Then astronomers can go to their telescopes and see if these predictions are right.

The first major prediction of the big bang theory came from Russian-American scientist George Gamow and his student Ralph Alpher. In 1948, they used the big bang equations to calculate what types of atoms would have been produced by the big bang. During the big bang, the entire universe was hotter than the core of a star, but only for the first three minutes. This was only enough time to leave the universe with 75% hydrogen gas, 25% helium gas, a few tiny traces of lithium and beryllium atoms, and nothing else. The big bang was not able to create any heavier atoms, no carbon, no iron, no nitrogen, and no oxygen. These heavier atoms must have been created much later, in the cores of stars which eventually exploded, spreading them through our galaxy.

Astronomers have been able to test this prediction by studying clouds of gas out between galaxies, which have never been anywhere near an exploding star. What we have found is amazing: Every intergalactic cloud has precisely the same chemical composition. Every intergalactic cloud is made of the exact mix of atoms predicted by the big bang theory: 75% hydrogen, 25% helium, traces of lithium and beryllium, and not the slightest bit of anything else.

But, the most dramatic prediction from the big bang equations came from Ralph Alpher and Robert Herman, also in 1948. They calculated that because the big bang filled every point in the entire

universe, even after 14 billion years, the afterglow of the big bang should still be out there, filling our sky. In 1965 Arno Penzias and Robert Wilson discovered that what we now call the “cosmic microwave background” really does fill the universe. Over the past 50 years, astronomers have measured this afterglow of the big bang with greater and greater precision: It is out there. It is powerful evidence of the reality of the big bang.

There was a beginning. There was a moment of creation.

Our Universe Has Laws

Your word, LORD, stands forever; it is firm as the heavens. Psalms 119:89

At the most fundamental level, physics tells is that our universe has laws. There are rational, logical, consistent principles behind the amazing vast diversity of our universe. We look out and see beautiful structures on all scales, from the vast archipelagoes of galaxies, down to the tiny structures inside the nuclei of atoms, and all of them are governed by the same set of physics laws. We point our telescopes out to the most distant galaxies, ten billion light years away from us, and we see that they composed of hydrogen, helium, carbon, iron, the same types of atoms that we have here on Earth. Everywhere we look, we see the same laws of gravity and electromagnetism, the same forces and energy at work throughout every corner of the universe, on all scales, through all epochs from the present day, back to the age of the big bang itself.

The laws of physics as we know them can be summarized with equations that can fit on one sheet of paper. Yet, when put into action in this vast universe, these laws are sufficient to regulate the motions of particles, atoms, molecules from water to DNA, living tissues, organisms, ecosystems, planets, stars, solar systems, galaxies, and the overarching structure of the universe itself.

The intricate and precise balance of these physical laws is truly astonishing. If any of the laws of nature were changed in even small amount, then our universe would not have formed stars, planets, life, and humans in the way that it did.

Gravity is the weakest fundamental force while the strong nuclear force is the strongest. The balance between these forces is amazingly precise. These forces are delicately poised, governing the intricate chain of events which has led to the development of human intelligence. Just after the big bang, the nuclear and electromagnetic forces were strong enough to form atoms of hydrogen and helium, but not of the heavier elements. Then the force of gravity was strong enough to gather these atoms together to form the first generation of stars, all enormous giants, where intense heat and pressure were sufficient to allow the strong nuclear force to create the atoms of carbon, nitrogen, and oxygen, which are so essential to human life. Then the interplay between the nuclear reactions and gravity caused these enormous ancient stars to explode, seeding the universe with these elements. Then electromagnetism allowed the gas to cool enough that gravity was able to gather materials together to form a second and third generation of stars, with each generation enriched with the ashes of their forebears. The electromagnetic cooling properties of these heavier elements allowed stars like our sun to form, with a more moderate mass, so that it and others could provide a steady, predictable

source of energy for many billions of years. From here the interplay of electromagnetic forces and quantum effects allowed amazingly complex chemistry to flourish in the oceans of the young Earth, which led to the development of the first living cells.

If any one of the four forces was just a little bit weaker or stronger, then it is difficult to see how the delicate chain of events which lead from the big bang to the evolution of intelligent life on earth could have happened. The beauty, the structure, and the balance of these fundamental physics laws, is truly awe inspiring.

Resonances in Scripture and Science

In this essay we have explored four points of resonance between the Creator revealed in the scriptures, and the science of physics. (1) The scriptures describe the unity of God, how there is only one Creator, one Author of all things. At the same time, unification is one of the central organizing principles of physics. Many of the more important developments in physics have come from finding a single deep theory which explains two apparently disparate phenomena, whether this is the motion of the apple and the moon, the operation of electric and magnetic forces, or the seemingly different natures of the electromagnetic and weak nuclear forces. (2) The scriptures tell us that God’s ways are very different from ours, at odds with our common sense. The discovery of Einsteinian relativity and the quantum theory revealed aspects of physical law so strange that they seemed paradoxical in the context of our expectations. (3) The scriptures tell us that our universe had a beginning, a moment when it first came into existence. Modern physics clearly establishes that our universe did indeed begin with a single big bang event. (4) The scriptures tell us of a Creator who is steadfast and true, a Creator who is reliable and stalwart through all things. At the most basic level, physics reveals that our universe has laws, and these laws are constant to the most distant views of our telescopes, to the deepest center of atomic nuclei, and throughout the entire history of the universe.

I’ll never forget the amazing moment of discovery when I did the Millikan oil drop experiment for myself as a college. I squirted a faint mist of oil droplets into the air from a little rubber bottle. Then I shined a bright light onto the droplets from the side, and looking through a microscope I could see a few of these tiny drops as they drifted down through the air, pulled by gravity. Next, I switched on an electric field. Some of the droplets had no electric charge, and continued drifting down at the same rate. But a few of the drops had picked up a little static charge, and they responded, dancing in my microscope as I twisted the knob, changing the electric force on them. I adjusted the voltage until one single drop hung motionless in the air, as the force of gravity pulling it down was exactly equal to my electric force pulling it up. This voltage then told me how much electric charge was on the droplet.

Over the course of an hour, I measured the electric charge on a dozen different oil drops and the results were amazingly clear. About half of the droplets carried exactly one electron’s worth of charge. Several of them had exactly two electrons of charge, and a couple had three electrons of charge. The data from my simple little experiment clearly measured exactly how much charge is carried by each electron. With a microscope and a few odds and ends, I personally measured one of the fundamental constants of the universe.

For me, physics is a deeply spiritual experience. Physics is a science based on careful, painstaking measurements of reality stitched together with subtle works of mathematical creativity. I treasure those special rare moments when patterns emerge, when beautiful, striking relationships of amazing power arise out of the fog, and when I see the fingerprints of the Creator.

Image credit for the Seagull Nebula: ESO

Fire Back: Where the Readers Respond

In which we discuss Tabby’s Star, the meaning of “up,” time dilation, and Christian scientists.

HD, a retired school teacher, writes in with several interesting questions.

I wondered….Could the structures observed around the Tabby star that are postulated be the constructs of the new Jerusalem that is being constructed to come to Earth some day?

She is referring to the star, KIC 8462852, sometimes referred to as Tabby’s Star. This peculiar object captured people’s imaginations after scientists admitted they haven’t been able to explain irregular changes in the amount of light it’s emitting. Observations suggest a close formation of small objects is surrounding the star, blocking out some of its light. One idea is that these objects could be a swarm of comets (see artist’s impression below), while another idea is that they are some form of “alien superstructure.” (Neither idea turns out to be well supported by observational data.)


HD’s idea is novel and interesting, but I think it’s unlikely for the simple reason that Revelation 21 tells us God is going to scrap this universe and start over with a new creation.

And when Jesus says “I have not yet ascended to my Father” and speaks many many times of Heaven…then it is a for sure thing. We can count on it. It is real. It is there. And….it is up. (ascend) So as a scientist who studies space, can you tell me ….where is up?? If I am in Gulfport, I can point up. On the other side of the planet, someone else can point up. So where, scientifically….is up??

“Up” in terms of space and in terms of scripture are two different things. In space, “up” is more accurately described as “out,” as shown below.



When Jesus talks about ascension, I don’t think He is going “up” (i.e. out) from the planet the way a rocket ship does, but rather He is transcending the universe similar to the way a three-dimensional creature would transcend a two-dimensional world. This animated sequence narrated by Carl Sagan illustrates the principle:

Then I saw a special on National Geographic about an experiment on distance and time. Using two atomic clocks, synchronized to perfection, one was left at the bottom of a tall mountain. One was taken to the very top. I think it was four days later the clock from the top of the mountain was brought down. There was a tiny, miniscule difference in time.   So, if 1,000 years are like a day to God (Scripture), how far out would you have to travel to have the 1,000 years equal to a day on Earth?

Gravitational time dilation results from differences in gravity. Despite the fact that it’s difficult for us to escape Earth’s gravity, it’s actually pretty weak, so there’s not much difference between the flow of time on the surface of the Earth and the flow of time out in deep space. It’s enough of a difference that engineers have to account for it, otherwise things like GPS wouldn’t work,  however, it’s not nearly enough to dilate time so that 1,000 years on Earth would be like a day for someone in deep space.

So, the question isn’t how far out you would have to travel in space to make 1,000 years equal a day, but how deeply into a gravitational field you’d have to go before time dilates that much. Turns out, it’s pretty deep, as in just a hair outside of the event horizon of a black hole.

It is amazing that more scientists haven’t become Christians.

There was a time when most scientists were Christian, particularly so in Newton’s time. It’s seems strange from our modern perspective, but in the 17th century, one had to be an ordained Anglican priest in order to hold a professorship at Cambridge. In the 17th century, American universities like Harvard and Princeton were religious institutions.

An entire thesis could be written on the subject, but suffice it to say, somewhere along the way Christianity not only ceased to be the dominant cultural force in the academic world, but academia became hostile to it. Still, the evidence for some kind of conscious creative force is there, and I suspect most scientists know it. English Nobel laureate physicist, George Thomson, observed, “Probably every physicist would believe in a creation if the Bible had not unfortunately said something about it many years ago and made it seem old-fashioned.” I think this is very much the case.

Image credit for Tabby’s Star: NASA/JPL-Caltech