Monday, December 13, 2010


Over at the BioLogos Forum, where their mission is to dispel the supposed conflicts between science and Christian faith, there are many fine posts and articles about such issues, especially evolution.  However, most of the writings are quite scholarly and not particularly engaging for the non-specialists.  Thus, this post is a trial of less technical responses to some of the questions that come up in the faith-science discussions.  As such, there no doubt will be some things presented here that will make experts cringe - if you are one of those cringing experts, let me know how to make improvements :-)

Question - The creation story in Genesis speaks of six twenty-four hour days for all of creation, and many Christians believe that this is literally true.  By using the genealogies of the Old Testament, the young earth proponents deduce that the earth has existed for about 6000 years.  However, nearly all scientists, including Christian ones, believe that the universe is very, very old and that the earth is old and that humans have been around for a long time.  Why do they believe this, and if it is true, how are we to understand Genesis?

Well, this could take a while!!  However, let's look at the reasons why scientists accept that the universe, the earth and humans have existed for a very long time.  It should be understood that many different disciplines address the question - astronomy, chemistry, geology, anthropology and biology all contribute to our understanding.  So, let's first look at the age of the universe.

Astronomy and the Age of the Universe

The age of the universe is currently calculated to be approximately 13.73 billion years old.  That's 13,730,000,000 years.  To put that into a bit of perspective, think about the length of a second versus that of a year - there are about 31.5 million seconds in a year; 10 years = 315 million seconds; 100 years =  3.15 billion seconds, which means that 13.73 billion seconds is over 400 years.  Go ahead figure out how many years 13 billion minutes would be; 13 billion hours; 13 billion days.  Since politicians seem to throw around a billion dollars with ease, go here for a nice graphic of a billion and a trillion dollars.

For centuries, humans have looked to the night sky for answers.  Ancient star-gazers gave us the astrological signs and the mythology of constellations [personally I can only recognize the Big Dipper and the Southern Cross, and maybe Orion's belt].   The Bible makes several references to "signs in the heavens" and "star" appears 17 times in 15 verses of the NIV.  However, today we have very sophisticated instruments for observation and measurements of the cosmos.  One of the measurements that we can make is of the different wavelengths or energies of light of various stars and constellations.  Everything we observe in the heavens appears to be moving away from us, and thus the universe is "expanding." 

How can we make this claim?  Let's start with something familiar.  Anyone who has stood and watched a passing ambulance, or locomotive, or car blasting its horn has noted that the pitch of the sound is higher as the source approaches you and then gets lower as the source passes you by.  Here is a short video of what is termed the Doppler Effect or Doppler Shift:


Cool, eh?  If you have a piano, go over and strike middle C.  No piano?  Use this:

Get sound effects & royalty free music at AudioMicro.

This note has a frequency of 261 cycles per second (cps); if you strike the middle A above middle C, you will hear a higher frequency of 440 cps; and as you might have thought, if you hit the A below middle C, you hear a lower frequency of 220 cps.  Thus higher pitches are more cps and lower pitches are less cps .  However, if the sound source is moving, there is a change in the "apparent" cps to you, the stationary observer, even though there is no real change in the cps of the source.

Here is an interesting analogy:  Suppose that you are a parent watching your child play at the beach. If the child stands still in the shallow water, you note that one wave reaches your child's position each second. However, suppose that the child decides to "rush out to meet" the waves. The child will encounter the waves more frequently as she rushes out toward the deeper water. Instead of one wave reaching her each second, she might meet two or three each second. Conversely, if the child "runs away from the waves" back into the shore, instead of one wave reaching her every second, a wave might only reach her once every 1.5 to 2 seconds. The child can change the "apparent frequency" of the oncoming waves through his motions. How much the frequency changes depends on the child's relative speed.

To impress [or perhaps depress] your relatives and friends, you can do a living-room demo of the Doppler Shift.  If you have a tuning fork, tie it securely to the end of a four-foot rope.  Strike the fork to illustrate the pitch of the fork.  Then, strike the fork and swing it around above your head and the folks will hear the increase and decrease in pitch as the fork moves toward them and then away from them.  If you are a bit concerned about swinging the tuning fork, just strike it and move it quickly toward and away from your captivated audience.  As another alternative, I like to use a piece of soft, flexible rubber tubing and the whistle from our small teapot.  Secure the whistle in the end of the tube and blow through the other end.  Then, as above, swing the whistle around your head and the folks will hear the pitch changes. 

Now - switching from sound to light.  The rainbow reminds of the multicolored nature of light.  And, as you may know, light also has characteristics of waves, and wave frequencies/energies correspond to color, like this:

And, the principles of the Doppler Shift also apply to light and to anything that has a wave as one of its characteristics.  Let's assume that you are stationary and a green light source is stationary - you see green.  But, if the light source is moving toward you, what color might you see?  Would there be a shift toward the blue or toward the red?  The "apparent color" would be of a higher energy/shorter wavelength, and would thus be blue-shifted.  If the green light source was moving away from you, the "apparent color" would be red-shifted.  Every energy source that we can measure "out there" in the universe is red-shifted, and thus everything is moving away from us.  Here is a "real" astronomer giving an explanation of this:

Here is another video, a bit longer and a bit more detailed, but definitely worth your time:

If you want to do an interesting visual for yourself, get a brightly colored balloon; blow it up about 1/3 of its maximum; use a black magic marker to make numerous dots on the balloon; circle one of the dots and call it our own Milky Way; now continue to blow up the balloon.  What is the relationship of the Milky Way to all of the other dots?  What is the relationship of every dot to every other dot?  As the balloon expands, every dot gets further and further away, and likewise, in our expanding universe, everything is moving further and further away from everything else.  You may also note that if you blow up the balloon at a constant rate, the dots move away from each other at a faster rate.  If you want to learn more details about how we measure distances to other places in our solar system and in the universe, read this.

Because of the known rate of the expanding universe, calculations can be made to trace backward in time to when everything in the universe was at one point - the "big bang" - and this is where the 13 billion year age of the universe comes from.  Probably the most important contributions to our understanding of all of this were made by Edwin Hubble and the spacecraft telescope that bears his name.  Here is a link to the amazing photographs from the Hubble telescope and below is an interesting summary of Hubble's work:

And here is a sneak preview of the successor to the Hubble Telescope - the James Webb Space Telescope:

Thus the heavens can declare the glory of God, and the heavens can also tell us a great deal about the history of our universe.  If we are to accept the findings of science regarding the age of the universe, then we must reexamine the literal interpretations of Genesis 1 and 2 and redefine how we read the texts.   A future post, hopefully by Pete Enns, Senior Fellow of Biblical Studies at BioLogos, will address these issues.

1 comment:

"Red" Green said...

Minor correction to paragraph 5: For centuries, humans.... " Everything we observe in the heavens appears to be moving away from us..." Actually only the galaxies have a systematic appearance of moving away (all except for a few that have "proper motion" toward us that exceeds local expansion - but that's not important here).

I like this essay. If you would like to add to the lack of literalness of the scripture I found another one just yesterday that I tried out: Abraham's descendants will be as numerous as the stars. Well, hmmm..., on a clear night in Canaan 2000 years or so ago you'd be able to count about 3000 stars. Hardly the millions of Israelites descended from Abraham.

The problem is that a large portion of the demographic targeted will say something to the effect "And isn't it neat how God made it all look so old to confound the wisdom of men?"

You might also considering adding that scientists don't do aging experiments just one way. "Adding to the astronomical data, which the ancient Israelite leaders used to declare God's glory, we have geologic data and other information encoded in the physical record that corroborates the age of the universe. By believing in what we can see, as well as the things unseen, we delimit God and make Him bigger than we can imagine, rather than creating Him in our own image."

Or something like that. I think it's important to get in somewhere in the essay that all of the age research is self-consistent and all the year-counting of the Bible is completely inconsistent with observation.