Is Light Slowing Down?

More Turmoil in Physics

In earlier articles, we discussed the nature of time and the fallacy of linear and absolute time concepts. We now know that time is a physical property and varies with respect to mass, acceleration, and gravity.1

Time is tied to our concepts of the curvature of space-time, and the velocity of light. The velocity of light is, in fact, a parameter which appears to affect almost every aspect of both cosmological physics on the large scale, as well as quantum physics in the particle scale. It is, of course, considered to be the fundamental constant of physics.

Historical Perspective

The early Greek philosophers generally followed Aristotle's belief that the speed of light was infinite. 2 As late as 1600 a.d., Johannes Kepler, one of the fathers of modern astronomy, maintained the majority view that light was instantaneous in its travels. Rene Descartes, the highly influential scientist, mathematician and philosopher (who died in 1650), also strongly held to the belief in the instantaneous propagation of light. He strongly influenced the scientists of that period and those who followed.

Speed of Light Measured

In 1677 Olaf Roemer, the Danish astronomer, noted that the time elapsed between eclipses of Jupiter with its moons became shorter as the Earth moved closer to Jupiter and became longer as the Earth and Jupiter drew farther apart. This anomalous behavior could be accounted for by a finite speed of light.

Initially, Roemer's suggestion was hooted at. It took another half century for the notion to be accepted. In 1729 the British astronomer James Bradley's independent confirmation of Roemer's measurements finally ended the opposition to a finite value for the speed of light. Roemer's work, which had split the scientific community for 53 years, was finally vindicated.

Over the past 300 years, the velocity of light has been measured 163 times by 16 different methods. (As a Naval Academy graduate, I must point out that Albert Michelson, Class of 1873, measured the speed of light at the Academy. In 1881 he measured it as 299,853 km/sec. In 1907 he was the first American to receive the Nobel Prize in the sciences. In 1923 he measured it as 299,798 km/sec. In 1933, at Irvine, CA, as 299,774 km/sec.)

Recent Discovery

Australian physicist Barry Setterfield and mathematician Trevor Norman examined all of the available experimental measurements to date and have announced a discovery: the speed of light appears to have been slowing down over the years! [Roemer, 1657 (Io eclipse): +/- 307,600 5400 km/sec; Harvard, 1875 (same method): +/- 299,921 13 km/sec; NBS, 1983 (laser method): +/- 299,792.4586 0.0003 km/sec.] They all are approximately 186,000 miles/second; or about one foot/nanosecond.)3

While the margin of error improved over the years, the mean value has noticeably decreased. In fact, the bands of uncertainty hardly overlap.

As you would expect, these findings are highly controversial, especially to the more traditional physicists. However, many who scoffed at the idea initially have subsequently begun to take a closer look at the possibilities.

Alan Montgomery, the Canadian mathematician, has also analyzed the data statistically and has concluded that the decay of c, the velocity of light, has followed a cosecant-squared curve with a correlation coefficient of better than 99%.

A New Perspective

This curve would imply that the speed of light may have been 10-30% faster in the time of Christ; twice as fast in the days of Solomon; and four times as fast in the days of Abraham. It would imply that the velocity of light was more than 10 million times faster prior to 3000 b.c. This possibility would also totally alter our concepts of time and the age of the universe. The universe might actually be less than 10,000 years old!

Other Implications

The key properties of the vacuum of free space include electrical permittivity, magnetic permeability, zero-point energy, and intrinsic impedance. If any of these properties change isotopically, then both atomic behavior and the speed of light would vary throughout the universe.

The product of magnetic permeability and electrical permittivity is the reciprocal of c2 . The permittivity of free space has not changed, but permeability has. It is related to the "stretching out" of free space at the time of creation. The "stretching" of the heavens is mentioned many times in the Bible. 4 Setterfield has analyzed 164 measurements of c, the velocity of light, gathered over the past 320 years, which reveal a statistically significant decay in c. When coupled with associated c-dependent "constants," the data includes some 639 values measured by 25 different methods.5 A comparison of dates in orbital time from history, archaeology, tree rings, etc., with atomic dates from a variety of radioactive isotopes has provided some 1228 data points over 4550 years.

Relaxation, or release, has set in, perhaps after the fall in Genesis 3. The shrinkage of free space could be the cause for the observed slowing down of the velocity of light. The "Redshift" may be caused by a decay of c. In fact, the universe may be contracting, not expanding.

A Tiff about Tifft

William Tifft, an astronomer at the University of Arizona, has been collecting data for about 20 years on redshifts, and it now appears that the universe might not be expanding. In the 1970's, Tifft noted that the redshift seemed to depend upon the type of galaxy that was emitting the light. Spiral galaxies tended to have higher redshifts than elliptical galaxies in the same cluster. Dimmer galaxies, higher redshifts than brighter ones.

Even more disturbing, Tifft has discovered that some clusters and pairs of galaxies exhibit only certain discrete values, rather than the more random distribution one would expect if the shifts were distance related. These redshifts appear in discrete quantum levels, similar to the energy states of subatomic particles in quantum physics. 6

These findings are not popular with astronomers or cosmologists, and emotions, even in physics, run deep. If the redshift is not a simple measure of velocity, then the conjectures about the Big Bang, and its derivative issues such as "dark" matter, 7 etc., tend to fall apart. The elaborate theoretical models of the Big Bang traditions may be headed for the scrap heap.

There is also the disturbing evidence that the redshifts change over time. There seems be some basic physics involved that has yet to be understood. These changes could be due to basic life cycles of galaxies, the nature of space or light itself, or other possibilities. 8

There have been a number of attempts to refute Tifft's observations. One recent one by Bruce Guthrie and William Napier, at the Royal Observatory in Edinburgh, measured the redshifts of 89 spiral galaxies. The results surprised the skeptics by uncovering data that supports the case for quantized redshifts.

If Setterfield proves correct, then this might also explain the quantization of the redshifts. Specific values of c govern the quantization of the emitted wave lengths, and quantized redshifts could result. 9

Radioactive Dating

Radioactive decay rates have changed. The decay of c affects the speed of nucleons in the atom, and the alpha particle escape frequency. Thus, all radioactive decay rates have decreased in proportion to c throughout the recent history of the universe. For many other reasons, the radio dating methods, carbon-14, potassium-argon, or any other atomic-clock method, are unreliable for very large ages.


The Second Law of Thermodynamics indicates that in a closed system, as time flows forward, energy in the universe is becoming less and less available. "Entropy" is the measure of the state of "energy unavailability" in an energy-containing system. Entropy always increases.

Orderly systems of molecules represent low entropy systems. Orderly systems tend, on their own, to become disorderly and chaotic through the processes of decay and disintegration. With passage of time the normal tendency of things is for such systems to become disorderly, chaotic, and randomized. Their "entropy" increases.

We experience this in our daily routine: we spend effort to organize our desktop, our garage, our school locker. Soon, however, as "random" events take their toll, everything tends toward randomness--the entropy increases. To bring order out of chaos, we must put in outside energy or information: instructions, codes, blueprints, and effort. Order comes from chaos only if someone makes it happen. Time plus chance always leads toward chaos--not order--without the intervention of outside intelligence.


In the beginning, there apparently was a close connection between the spiritual and physical realms, until the fall of man in Genesis 3.

The universe was pronounced "good"--free of defects--by the Creator. A high degree of order originally existed; that is, there was very low entropy.

But then Adam fell and the curse of sin began. Disorder and entropy began to increase. Could the slowing down of the speed of light have begun with the increase of entropy and, thus, both be a result of the curse brought about by sin?

The subsequent death, dying, decaying, and destroying processes affected not only man, but nature as well (Romans 8:19-23).


The possibility that the speed of light is not a "constant" after all and has been slowing down is highly controversial and conjectural. Yet, some of the most dramatic changes in scientific perspective come only after much debate, vigorous opposition, and the like.

The entire field of physics is presently in a state of upheaval. The particle physicists have decided there is no causality, and that the universe has at least 10 dimensions. The redshift has been discovered to be quantized and that may shatter previous conceptions of our universe. Particle physics has totally altered our concepts of reality.

Many of today's scientific orthodoxies, however, originated from yesterday's unpopular heresies. The apparent decay in the velocity of light may be another of these controversial "heresies" looming on the horizon of modern physics. Only time will tell.

But the Bible changes not. It doesn't need to.

The Reality of Eternity

There is part of you that is not physical, and therefore has no time: it is eternal.

Our Creator has provided a destiny for us that is so fantastic that it is entirely beyond our own eligibility, or ability, to earn it. That is why God has provided for our eligibility through His Son. His plan of redemption is available for the asking. But it's up to us to accept it. Throughout eternity you will either be in the presence of God, or separated from Him.

What will it be for you?

(See also Chuck's interview with Barry Setterfield on


  1. Personal UPDATE, Jan. 1993, p.12.
  2. Exceptions: Empedocles of Acragas (c. 450 b.c.); also Moslem scientists Aviecenna and Alhazen (1000 a.d.) both believed in a finite speed for light; Roger Bacon and Francis Bacon (1600 a.d.) both believed in a finite speed of light.
  3. A dynamical second is defined as 1/31,556,925.9747 of the earth's orbital period and was a standard until 1967. Atomic time is defined in terms of one revolution of an electron in the ground state orbit of the hydrogen atom.
  4. Isa 40:22; 42:5; 44:27; 45:12; 51:13; Jer 10:12; 51:15; Zech 12:1; the heavens as a "scroll": Isa 34:4; Rev. 6:14.
  5. See bibliography for references.
  6. Sobel, Dava, "Man Stops Universe, Maybe," Discover, April 1993.
  7. "The Missing Universe," UPDATE 2/93, p. 5-9.
  8. "Is Light Slowing Down," UPDATE 3/93, p. 12-16.
  9. In a varying c scenario, emitted energy flux remains unchanged, upholding the Stefan-Boltzmann law. Power is thereby conserved. High c values result in lower photon energies at emission, and a consequent redshifting of light from distant astronomical sources.
  • Dolphin, L., and Montgomery, A., "Is the Velocity of Light Constant in Time?" Galilean Electrodynamics, 1993.
  • Setterfield, B., The Speed of Light and the Red-Shift, pre-publication paper received by private communication. (Box 318, Blackwood, South Australia, 5051.)
  • Setterfield, B., and Norman, T., The Atomic Constants, Light, and Time, Invited Research Paper, SRI, August 1987.
  • Troitskii, V.S., "Physical Constants and the Evolution of the Universe," Astrophysics and Space Science, Vol 139, pp. 389-411, Dec. 1987.