Invisible but Real

Before discussing the reality of another portion of the invisible electromagnetic spectrum, I’ll ask my readers to join me on a field trip.

Some of the most memorable field trips with my science classes were visits to the museums of the Franklin/Sterling Hill area of northern New Jersey. At the Sterling Hill Mining Museum we walked through old mine tunnels of eons-old crystallized limestone interlaced with the leftovers of commercial minerals recovered during mining operations of long ago. I recall having a sense of strange reverence while walking through 1800 feet of cool, dark mine shafts in the bowels of the earth. Comparing human history with the age of these rocks, these rocks are about 20,000 times older.

The geological complexity of this area provides us with well over 300 different minerals, several dozen of which are found nowhere else in the world. We considered one room at the Franklin Mineral Museum to be one of the highlights of our visit. In ordinary light, we entered a long room--the fluorescent room--with a fairly ordinary array of rocks displayed behind large glass panels. But these rocks were different. Before us was one of the world’s foremost fluorescent mineral collections.

Upon first entering the “fluorescent room” the guide spoke about the minerals while the visible overhead lights were shining. Ultraviolet (UV) light (invisible wavelengths shorter than visible violet) was also shining on the display. At a given moment, the overhead visible lights were turned off. The many specimens of fluorescent minerals, however, continued to glow with a pleasing variety of different hues and brightness. The 1960s crowd may have called such a display “psychedelic.”

What explains the fluorescence? Electrons in the atoms are forced unnaturally to different “energy levels” by the UV light. As those electrons return to their normal energy levels, they emit visible light of a different wavelength--a visible wavelength this time. J.J. Thomson and other 19th century scientists described moving electrical charges as the source of all electromagnetic radiation. Moving electrons generate oscillating electric fields.

Invisible ultraviolet waves come in various wavelengths and have other effects apart from making certain minerals fluoresce. Some cause sunburn; others are beneficial to the body in measured quantities. Certain wavelengths have a germicidal function. The atmosphere filters out most UV coming from outer space.

Spiritual applications and object lessons abound. In fluorescence, the mineral’s source of energy to emit visible light is outside of itself. This reminds us of a similar term often used in scripture: power. In dozens of scripture passages, the power source for righteous living is outside of ourselves. God the Creator is the external source of the Christian’s power to achieve conversion and lead a righteous life.

And There Was Light

When we flip on a light switch, wonderful things happen. In a subjective sense, our path is illuminated and objects become visible. But in a scientific sense we must explain the events in more complex terms. In our last three posts, we’ve spoken about the wonders of electromagnetic waves. We could also speak of those waves as packets of energy called photons.

White light bulbs emit thousands of different wavelengths together. The longest and shortest of them do not differ in wavelength very much. The tiny difference, however, is vitally important. A prism is able to separate the wavelengths. The longest of them (about 1/40,000 inch) impact our eyes and brain and we see “red.” We see the shortest (about 1/70,000 inch) as “violet.” The in-between wavelengths are seen as orange, yellow, green, and blue.

At the speed light travels--300,000 km/sec--trillions of these waves strike our eyes each second. When we see an object giving off red light, or appearing red, we are really seeing light which has a frequency of 430 trillion hertz (Hz). Violet colored objects emit light with a frequency of 750 trillion Hz. Other colors fall between these frequency values. Scientists use Hz to indicate the number of waves passing a given point per second. Therefore, when we observe red light or a red object, 430 trillion electromagnetic waves pass into our eyes each second.

We do not comprehend such enormous numbers. At the 1962 Seattle World’s Fair, I viewed the display of one million silver dollars. Even with that visual aid, one million was difficult to grasp. A trillion (a million million) is certainly beyond our comprehension, whether in respect to waves of light entering our eyes each second, or as a figure to quantify our national debt. Scientists have determined wavelengths and their frequency with great precision.

Visible light falls between the wavelength range described above. In our environment, there are uncountable different wavelengths longer than these; uncountable billions of wavelengths are even shorter. These longer and shorter wavelengths exist abundantly all around us, but they are all invisible to humans. Our very existence would be impossible without them.

The imagery of light in scripture is beautiful and bountiful. Science knowledge in the 21st century helps us extend our applications of such imagery. “I am the Light of the world” refers to the spiritual illumination provided by Jesus Christ and is a metaphor for salvation. The created light in Genesis enabled man to inspect the glorious works of God. Physical light often accompanied the presence of Deity.

Our current knowledge of light evokes a sense of wonder at the glory of our created order. We may visually observe the beauty and function of the physical creation and the life forms it supports, producing reverent worship. While contemplating all this, we may use human terms to exclaim simply, “God had great ideas!”

A Spectrum of Possibilities

Science terms or definitions are necessary, but knowing a definition and understanding a subject are sometimes not the same. With that disclaimer, I’ll offer this definition of the electromagnetic spectrum (EMS). The electromagnetic spectrum is the complete range of possible wavelengths of electromagnetism, from longest to shortest.

Imagine the length of a long piece of string to represent the distance between electromagnetic waves. We could cut the string in any fractional length we choose, and continue to divide the string into smaller and smaller pieces. In theory, there is no limit to how short the pieces of string could be cut or how many pieces we could cut. It’s also possible to make longer and longer pieces of string by tying on additional pieces. Down the road we wind up with an infinitely large number of string pieces of many different lengths. Likewise, possible wavelengths of electromagnetism are virtually infinite.

Electromagnetic waves include radio, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. These range in length from many kilometers to only trillionths of a centimeter. In the following brief primer on electromagnetic waves, we will use radio waves as an illustration. The length of waves in the radio band of the EMS varies over a wide range.

All electromagnetic waves are described in terms of packages of electromagnetic energy (photons) traveling at 300,000 km/sec. They are described according to wave length--the distance between the waves. In addition, they are described according to frequency--hertz (symbol Hz)--the number of waves passing a given point per second. All AM radio stations broadcast on the “medium wave” band of the radio portion of the EMS. At the 300,000 km/sec speed, an AM radio station at 600 on the dial sends out 600,000 waves, or photons, per second. It is said, therefore, to have a frequency of 600 kHz (600,000 Hz). Your radio receiver detects them and converts the information in the waves to audible, intelligible sound. Wavelengths of the 600 kHz AM station--the distance between one wave and the next--are about one-half kilometer.

My personal fondness for investigating the EMS may more aptly be described as astonished fascination. In lighter moments I have stated that when this created order ends and the New Creation begins (Revelation 3:12; Revelation 21), I would like to discover, directly from the Creator of this present order, more mysteries of the EMS I did not understand. Included in the questions would be why different waves have such a markedly different effect on man, our equipment, and our environment, when the only physical difference between them is a difference in wavelength. In many cases, that difference is unimaginably small.

The only electromagnetic wave mentioned specifically in the Bible is light, a topic for another post. The scientific knowledge of our day enriches our appreciation of scripture’s spiritual imagery concerning light.

Timeline Trivia

One of my pastimes is personal family genealogical research. I enjoy pinpointing family events and connecting them with people and dates in history. Which family life spans overlapped those of famous people? Who was living when certain historic events occurred? What family member was alive, for example, when a certain scientific discovery was made?

My maternal grandfather was born just before the Civil War and died a few weeks after my birth. He was alive, therefore, in 1864 when brilliant physicist James Clerk Maxwell (1831-1879) developed his famous theory of electromagnetism which unified many observations of scientists who lived in previous decades.

Maxwell’s theory explained waves of electric and magnetic energy traveling at right angles to each other and to their direction of travel. I asked my students to imagine a tiny “package” of magnetism, the invisible force surrounding their childhood magnetic toys which attracted or repelled each other. They also imagined “packages” of electric force which, when pulsing through a copper wire, could deflect the needle of a nearby compass. By this, students were able to visualize the intrinsic relationship between electricity and magnetism.

The students needed to imagine these “packages” racing off through space. Through his equations, Maxwell calculated that the speed of these “packages” (waves) should be about 300,000 km/sec (186,000 mi/sec). Since light was known to travel at that speed, he correctly theorized that light was an electromagnetic wave. And he predicted that scientists would later be able to generate them artificially. Radio waves were first produced by Heinrich Hertz in 1886.

How are these waves produced? Another giant of science was J.J. Thomson (1856-1940). He was alive until 1940, several years after my birth. In 1897, this Nobel Prize winner discovered electrons: tiny negatively-charged particles present in all matter. In the late 19th century, Thomson and others realized that when electric or magnetic fields change position, or oscillate, electromagnetic waves are generated. As the atoms in all the objects around us vibrate constantly with kinetic energy, the electrons in them also oscillate. What is the result? The electrons and the magnetic fields around them also oscillate. Electromagnetic waves are produced.

My grandfather raised his older children on the prairies of Oklahoma during the late 19th century. His older children knew nothing of radio, microwaves, infra-red, the electromagnetic nature of visible light, ultraviolet, X-rays, and gamma rays. Discoveries and applications of electromagnetic waves were in their infancy. And yet, they feared God deeply. With respect to our fear of God, what impact does our present knowledge have on us?

Ubiquitous Radiant Energy

"Pulsing through our classroom walls and through your bodies at this very moment are hundreds of different forms of electromagnetic radiation! How are you feeling as a result?" This attention-grabbing statement produced mainly quizzical expressions on my students’ faces. But it also triggered fascination and an investigative frame of mind. When the electromagnetic spectrum unit was complete, I hoped it had also evoked a sense of wonder.

One of my favorite topics of study during my years as a classroom teacher was the electromagnetic spectrum. In multiple ways we are continually impacted by it. Where, then, do we begin in our explanation? The matter surrounding us is composed of elements or compounds of elements, or mixtures of elements and compounds. The smallest units of elements are atoms.

Little more than a century ago, the structure of the atom was discovered: a dense nucleus containing one, or more often, a cluster of electrically positive protons, together with electrically neutral neutrons. Surrounding the nucleus is a cloud of negatively charged electrons. In the early 1900s it was shown that most of the atom is just empty space. Different elements were composed of different numbers of protons, neutrons, and electrons.

To understand the nature of the ubiquitous radiant energy surrounding us, we must realize that all atoms possess kinetic (motion) energy at all times. All substances, therefore, possess heat. The higher their temperature, the greater their kinetic energy. Even objects from our kitchen freezers have heat: they are hundreds of degrees above absolute zero--the coldest temperature possible. Atoms may be energized further in many other ways.

As atoms move, their electrically charged particles move with them. When electrical charges move, they release packets of energy called photons. These packets behave like particles, but they also have characteristics of waves. Each instant of our lives we are constantly impacted by a flood of photons or waves, also known as electromagnetic radiation.

Light, a tiny fraction of the many hundreds of forms of electromagnetic radiation, is visible to humans. Most of the remaining forms are not detectable by our human senses. But the multitude of tasks for which they have been harnessed in our era of advanced technology challenge the imagination. In upcoming posts I will discuss more details of the importance and fascination of the electromagnetic radiation which surrounds us.

The Apostle Paul wrote of God’s creation of invisible as well as visible things. For him the invisible things were no less real: “For by Him all things were created: things in heaven and on earth, visible and invisible…” (Colossians 1:16 NIV). Scientists of the 21st century are making more and more discoveries of the reality of the invisible.

William Whewell, Polymath

One definition of Renaissance man is “one who has a wide range of accomplishments and intellectual interests.” The seldom used term polymath conveys a much stronger meaning: a very learned person with broad and comprehensive knowledge in many fields. In our day of narrow academic specialization, rare is the modern person worthy of such a description.

William Whewell (1794-1866) was a true polymath. A priest in the Anglican Church, he was better known for achievements in fields other than theology. He possessed expertise in mathematics, architecture, educational reform, moral philosophy, astronomy, mineralogy, and history and philosophy of science, to name a few. In the latter area he is known for defining what he termed “fundamental ideas,” supplied by our own minds. Scientists formulate such ideas midway between the purely ideal (mind) and the purely empirical (experience), drawing upon both.

An important historian of science, Whewell, an early advocate of design theory, has received less attention than he deserves. His writing reminds us of better-known modern science philosophers such as Karl Popper, Michael Polanyi, and Thomas Kuhn. Whewell coined the terms “scientist” and “physicist” as well as other well-known science terminology. He consulted with famous science figures as diverse on the theological spectrum as Charles Darwin and James Clerk Maxwell.

He used the term “colligation” to describe the bringing together of isolated facts to form a unified concept or relationship and coined the term “consilience” to mean a joining together of concepts in order to achieve an even broader conceptual framework. These are terms used by today’s science philosophers to describe how the discipline of science works.

Within his concept of natural theology Whewell described our human ideas about the world as “shadows” of Divine ideas. Our explanations of nature’s laws, therefore, should preclude seeing those laws as “an accident on a cosmic scale.” Many of Whewell’s proposals may qualify him to be recognized as the originator of intelligent design theory, a term formally in use only in the last several decades.

Whewell was commissioned, in 1839, to write one of the eight Bridgewater treatises. These were scientific writings which purposed to speak “on the Power, Wisdom and Goodness of God as manifested in the Creation.” His standout treatise was titled “Astronomy and General Physics, Considered with Reference to Natural Theology.” Each treatise was book-length, suffused with arguments to demonstrate design in nature. In just a few introductory pages, Whewell used dozens of poetic terms for God, including Divine Governor, Intelligent Author, and Supreme Ordainer.

A reading of several dozen pages demonstrates the enormous changes in scientific writings from the early 19th century to the early 21st. This change is a mirror of the secularism progressively imposed upon our society beginning in the 19th century and accelerating in the 20th and 21st. Whewell wrote, “It may be interesting…to show how the views of the creation, preservation, and government of the universe, which natural science opens to us, harmonize with our belief in a Creator, Governor, and Preserver of the World.”

Whewell’s theology leaned toward Christian universalism. As such, it differed from the orthodox views of brilliant contemporary scientist James Clerk Maxwell. But his concepts of a Creator/Sustainer were, nevertheless, very strong, as evidenced in this statement: “It will, we trust, be difficult or impossible to exclude from our conception of this wonderful system, the idea of a harmonizing, a preserving, a contriving, an intending Mind; of a Wisdom, Power, and Goodness far exceeding the limits of our thoughts.” Most of the treatise was purely scientific without additional devotional statements. The scientific concepts of his treatise were far more advanced than one would think possible for that generation.

One may only imagine what sort of reaction would greet the submission of a similar scholarly scientific article to a popular publication in the 21st century. I found Whewell’s Bridgewater treatise to be inspirational. But while reading most of today’s science writings, we must remember that seeing overlap of the domains of science and religion is an application we, as readers, must make on our own.

Bird Exuberance

Hidden in the verses of Psalm 148 is an unusual directive to sea creatures, all ocean depths, weather phenomena, mountains, trees, and wild animals to “Praise the Lord from the earth.” This instruction applies to “small creatures and flying birds.” So I applied these verses to my observations of the unique behavior of birds in our wooded, northwestern Illinois neighborhood.

For several years I have noticed that there are periodic episodes of collective, ebullient behavior among the feathered friends inhabiting our property. The behavior may be described as pure exuberance, having little purpose except obvious enjoyment. Several species of birds, primarily cedar waxwings, robins, and a few others, collect together in treetop crowds and fly noisily and swiftly from tree to tree, frolicking and feeding. After a few minutes the bedlam ceases, only to be resumed later. When this occurs, I tell my wife the birds are “going crazy” again. I’ve seen mixed groups of warblers exhibit similar behavior, especially in autumn.

Other bird behavior provokes amusement in me as an observer. With sanctified imagination, I could speculate that our birds are obeying the poetic directive of the psalmist that even the animals should give praise to their creator. If inanimate heavenly bodies like the sun, moon, and stars are called upon to offer praise, merely by displaying their beauty and glory, we might also view the deliberate antics of neighborhood avian entertainers in the same way.

Some members of a large group of young cedar waxwings recently showed off their joie de vivre in our leafless black walnut tree. They entered and exited a deserted nest structure, pulling off dead leaf stems and deliberately dropping them to the ground. Then, closely facing each other, opened and closed their bills as if speaking with each other. Cedar waxwings are known to pass food items down a row of birds sitting on a branch until one bird finally eats it. Other bird species soar in groups on rising air drafts, cool and clean themselves in water puddles, or gather in social groups to fly off deliberately toward destinations known only to them.

I could continue to describe the entertaining antics of crows, hummingbirds, owls, blue-jays, and many more. A strong case could be made that if the antics of our avian entertainers amuse and entertain, our own human emotions of praise are heightened.

A previous post described spring bird behaivior in our area:
http://jasscience.blogspot.com/2008/05/from-silence-to-song.html

Horatius Bonar, known as the 19th century prince of Scottish hymn writers, wrote, “Thus the air is vocal. It has a hallelujah of its own. The ‘flying fowl’ praise him. This is creation’s harp…which each sunrise awakens, “turning all the air to music.” Charles Spurgeon, 19th century “Prince of Preachers,” wrote in The Treasury of David, “Birds of every wing are called upon to join the universal worship. No one can become familiar with insect and bird life without feeling that they contribute a wonderful chapter in the history of divine wisdom.” I encourage readers to take quality time to observe the praise-givers.