What Is Light?
from the May 09, 2016 eNews issue
Human vision is utterly amazing in its ability to receive and process a wealth of information concerning levels of light intensity, colors, motion, and stereoscopic depth of field. However, as wonderful as our eyesight is, we are able to see only electromagnetic waves between 400 and 700 nanometers in wavelength.
Young Isaac Newton in 1666 used a prism to break visible white light into the rainbow colors of the spectrum, giving impetus to the development of what is now the vast science of optics. Discovery of the wave nature of light soon led to the realization that our universe is permeated with electromagnetic waves ranging in wavelength over at least 16 orders of magnitude — from ultra-low-frequency radio waves, which are tens of kilometers in wavelength, to cosmic rays with wave crests and troughs only a millionth of a millionth meter apart.
Just in our century, science has quickly extended the range of the eye for explorative purposes. Many different kinds of electronic sensing instruments now tell us vastly more about the cosmos than our eyes alone can tell us directly.
Light from the sun arrives at the top of the earth’s atmosphere at a power level of about one kilowatt per square meter. It is this heat and light from a modest star (surface temperature only 5500 degrees C), that all life processes on earth are ultimately driven. Without the sun’s constant energy input, our planet would quickly radiate away its latent heat and freeze us and everything else very solid in short order.
Heat and light from the sun are obvious, but we are unaware of cosmic rays penetrating our bodies at the rate of perhaps 10 per second. Nor do we realize that radio and television signals from a hundred stations fill our living rooms. Many of these “rays” pass through our bodies unimpeded. Light waves, radio waves, heat signals, X-rays, and the like, are electromagnetic (EM) radiation — all forms of which can transmit energy and carry useful information even across vast reaches of “empty” space. The signal speed of EM waves ranges upwards to a maximum value which is the current speed of light.
In this century has also come the realization that we can equally well describe light and other EM radiation as if it were corpuscular in nature. EM radiation is a result of moving electrical charges (currents), and all forms of EM radiation can be described mathematically as consisting of streaming photons. Each photon constituting a “particle” of light has an energy equal to Planck’s constant times the speed of light divided by the wavelength. (Photons are very small, yet the human eye is sufficiently sensitive that we can sometimes detect even a single light photon with dark-adapted eyes).
Whether one uses a wave model or a particle model for light is largely a matter of convenience for the physicist. The concept of “wave-particle duality” is well established by experimental evidence and the excellent models of Quantum Mechanics.
Gravitational forces seem to us to be powerful, because it is gravity which holds us to the earth’s surface and makes us work hard to lift and move things. However, the force of gravity is actually some 42 orders of magnitude weaker than the electrical forces, which generate light waves and radio waves!
Because of this huge difference in energy levels, we actually know little about gravity. For instance, many scientists have tacitly assumed that gravity signals, and the force of gravity between masses, are communicated (“mediated”) back and forth by streams of photons traveling at the velocity of light — some have assumed that gravity will be explained as arising from some type of EM wave. It is now more probable that gravitational forces are communicated by particles called gravitons, which are very much smaller than photons.
Furthermore, the speed of gravitons is apparently some ten orders of magnitude higher than the current speed of light. This raises the possibility of space travel throughout the entire known universe in very reasonable time periods. From energy considerations (in the universe considered as a whole entity) it now appears that the speed of light initially had the same high value as gravity still has, but the speed of light has decreased whereas the speed of gravity has not. [Ed. Note: Many competent scientists disagree with the theory that the speed of light has decreased.]
A great frontier lies before us now in better understanding gravity. For example, we cannot as yet be certain whether the hypothesized gravity waves are transverse in nature (as are EM waves), or compressional (like sound waves).
Suffice it to say that energy and information can be transmitted across the universe by means others than ordinary photons. That is, energy and information transmission in the physical world is probably not always electromagnetic in nature.
(And this is not taking into account how prayer and spiritual forces travel between God, men and the angels — about which we know next to nothing.)
On the First Day of creation week, having brought into existence space, time and matter, the second creative act of God was (I believe) the creation of light. Light was spoken into existence by the Second Person of the godhead, Jesus, the Logos or Word of God:
And God said, ‘Let there be light’ and there was light.
I like to think of this second event in God’s work of creating everything as the making of a vast energy source. The Lord then incorporated potential and kinetic energy reservoirs in many forms into His universe as He constructed things during the six days of creation. These energy endowments would allow the universe to function indefinitely with built-in power supplies. (Before The Fall I think this energy supply also included means of replenishment of reserves to make up for dissipation and losses).
The statement “Let there be light” may mean (in my opinion) “Let there be energy of all wavelengths and in all forms.” I believe it was from these four working substances created on Day One — (1) space, (2) time, (3) matter and (4) energy — that God constructed (and filled) the universe we live in. In His work as Creator, the Son of God was the “master craftsman” of Proverbs 8.
(Note: I have tried to clarify the events of creation week in my current thinking in my article “The Uniqueness of Creation Week,” available on my website. I reserve the right to learn and grow and change my views!)
The activity of creation week involved many separate actions by all the Persons of the godhead, as can be seen by the numerous action verbs in Chapter 1 which refer to God.
Many good people will probably not agree with my own interpretation of the opening verses of Genesis — so I won’t be dogmatic about the model I have just suggested. Dozens of books and hundreds of scholarly theological papers have disputed exactly how to interpret these opening verses of Holy Writ and I don’t claim to have the final word by any means. The important point is that light, as we know it and understand it in the physical world, was created by God on the First Day of creation.
The Bible says that “God is Light” and this is not the same as saying “Light is God.” If we claimed that the Light shining forth on Day One of creation week was simply God Himself we would have major problems — because God is a Spirit and He does not directly emit protons or waves! Such a hypothesis as saying that the Light of Day One came from God Himself puts us on the fast road to pantheism, which we must refute. The God of the Bible is separate from, and transcends, His creation.
Because God is Light, a more profound problem appears when we consider other passages in the Bible which speak figuratively of light, and of spiritual light. Writing to Timothy, Paul the Apostle tells that God, “alone has immortality, [and that He] dwells in unapproachable light, whom no man has seen or can see.” (1 Tim 6:16). Moses, who enjoyed a very intimate relationship with God, on one occasion asked God that He might see Him as he was:
And Moses said, “Please, show me Your glory.”
Then God said, “I will make all My goodness pass before you, and I will proclaim the name of the LORD before you. I will be gracious to whom I will be gracious, and I will have compassion on whom I will have compassion.”
But God said, “You cannot see My face; for no man shall see Me, and live.” And the LORD said, “Here is a place by Me, and you shall stand on the rock. So it shall be, while My glory passes by, that I will put you in the cleft of the rock, and will cover you with My hand while I pass by. Then I will take away My hand, and you shall see My back; but My face shall not be seen.”
— Exodus 33:18–23
The whole point about God’s being Light is that the splendor and radiance of His immediate presence is so intense it must be veiled in clouds of thick darkness. Otherwise mere mortals would be burned to a crisp if they came into the unveiled presence of His effulgent power.
Spiritual realities are more permanent and more substantial than the shadows they cast into our physical world. Jesus is likened to the rising Day Star and called by Malachi the “Sun of Righteousness” — symbols which suggest to us that His true splendor is greater than that of any star or any known source of light and power in our physical world.
Revelation describes the face of Jesus as shining like the sun in full strength (Rev 1:16).
Light is a common symbol in the Bible for truth as opposed to ignorance and error. “Enlightenment” means true understanding and comprehension in the inner man. It was Jesus who declared, to the consternation of his enemies, “I am the light of the world. He who follows Me shall not walk in darkness, but have the light of life.” (John 8:12).
So in some way there is a connection in Scripture between spiritual light and life itself! The New Testament furthermore insists that the man Christ Jesus is the exact visible expression of God the invisible. It is by knowing Jesus that we who once were “sons of darkness” become “sons of light.” Unlike Moses we are invited to look full into the face of Jesus:
…we all, with unveiled face, beholding as in a mirror the glory of the Lord, are being transformed into the same image from glory to glory, all this comes from the Lord who is the Spirit.
— 2 Corinthians 3:18
God, were His Light unveiled, would fill and flood the entire universe with His presence to such a degree that there could be no ordinary night time anywhere. Therefore the spiritual world where He dwells, surrounding us on all sides, a world in which the material creation is embedded, is not only more solid than our world, it is also brighter — it is full of light in fact. Living as we do at present in a world still relatively dark, we await the coming of the Dawn.
This article was originally published in the May 1998 Personal Update News Journal.
S.R. Filonovich, The Greatest Speed, 1983, Mir Publishers, 2 Pervy Rizhsky Pereulok, 1–110 GSP, Moscow, 129820. A good discussion of the physics of light at an elementary level.
Sobil, Michael L., Light, 1987, The University of Chicago Press, Chicago.
Bova, Ben, The Beauty of Light, 1988, John Wiley and Sons, New York.
– FROM: KHouse.Org