Physics: A Challenge to 'Geological Time'

I. Lord Kelvin Urged Geologists to Accept Limitations Set by Physics on the Earth's Age.

In contrast to the narrow specialization of present-day scientists some great physicists in the nineteenth century made significant contributions to numerous branches of science. England recognized this breadth and depth in Sir William Thomson and elevated his title to Lord Kelvin. It was Kelvin's brilliant thermodynamic analysis that gave us the absolute temperature scale that bears his name. When the Atlantic cable was laid it took the ingenious electromagnetic developments of Kelvin to make it a workable device. His best papers are to be found in a six volume set, Mathematical and Physical Papers, Lord Kelvin, (Cambridge University Press, 1911). Many of those papers employed physics to expose the errors inherent in the long-age concepts held by uniformitarian geologists. One paper was entitled: "The 'Doctrine of Uniformity' in Geology Briefly Refuted"; another was entitled: "On the Age of the Sun's Heat". Many of his papers dealt with the age of the earth.

In reference to the President of the Geological Society, Kelvin stated: "I believe . . . Professor Huxley . . . did not know that there was valid foundation for any estimates worth considering as to absolute magnitudes" (greatest possible age of the earth). When Kelvin pressed Sir Andrew Ramsay for strict physical limitations on geological time, Ramsay begged the question with the remark, "I am as incapable of estimating and understanding the reasons which you physicists have for limiting geological time as you are incapable of understanding the geological reasons for our unlimited estimates." Kelvin replied, "You can understand perfectly, if you give your mind to it" and "Physicists are not wholly incapable of appreciating geological difficulties."

In later years Kelvin thought that geologists had accepted the limitations on the earth's age imposed by the principles of physics, which Kelvin had logically set forth. He wrote: "It was only by sheer force of reason that geologists have been compelled to think otherwise, and to see that there was a definite beginning, and to look forward to a definite end, of this world as an abode fitted for life." But Kelvin's optimism was premature. Evolutionary geologists had not and still have not accepted the limits imposed by physics upon "geological time"; their evolutionary tug has always been for more time. The compiler of Kelvin's papers points out that the geologists never accepted Kelvin's limits on the earth age: ". . . the complaint had become widely prevalent that in the hands of Lord Kelvin and the physicists the evolution of the terrestrial strata, and of the life of which they contain the evidence, had been hurried up too much."

Kelvin faced up to the miracle of the creation of life. He had no respect for the materialistic views of the origin of life and stated plainly: "Mathematics and dynamics fail us when we contemplate the earth, fitted for life but lifeless, and try to imagine the commencement of life upon it. This certainly did not take place by any action of chemistry, or electricity, or crystalline grouping of molecules under the influence of force, or by any possible kind of fortuitous concourse of atoms. We must pause, face to face with the mystery and miracle of creation of living creatures."

II. Analyses that Yield Limits on the Age of the Earth.

In order to understand how physical measurements and logical analyses may lead physicists to the conclusion that the earth is relatively young, one needs to understand how a "constraint" may be applied in physics. The constraint may be a limit placed on the initial state or original condition of the earth. For example, Kelvin assumed that in no case could the initial temperature of the earth have been greater than a white hot temperature. That constraint set the upper limit on any initial temperature to be assumed for the earth. Hence even though the constraint chosen is somewhat arbitrary, it is still based upon a very reasonable assumption.

This analysis finds an extreme limit. Whereas the actual value may be much smaller, at least a "lid" had been imposed on possible values to consider. Kelvin never said that the age limits set by his physical reasoning gave the actual age of the earth. He simply said its age was not greater than those limits.

Once a particular constraint, or initial state, has been assumed, the physicist methodically derives his conclusion from the laws of physics. We shall be particularly concerned with the laws of thermodynamics, mechanics, gravitation, and electromagnetism. These laws govern the respective physical processes that change the value of the earth's physical parameters from those that were there in its initial state. These processes always involve decay. The physicist recognizes at least three kinds of decay that have been taking place on the earth: (1) The rate of rotation of the earth has been slowing down as a result of tidal friction and other factors, including some less known effects such as that of the solar wind drag on the earth's magnetic field. (2) Thermal energy within the earth has been decaying through the process of conduction to the surface of the earth and radiation out into space from the surface of the earth. (3) Magnetic energy associated with the earth's dipole magnet has been decaying, causing a growing diminution of the magnetic field that shields the earth from cosmic and solar radiation hazards.

The measured decay rates associated with each of these decay processes, together with reasonable constraints on their initial state, enable physicists to find limits to the possible age of the earth. Kelvin used the first two decay processes to establish limits of: (1) less than a billion years; (2) less than 24 million years; respectively, on the earth's age. Of course the shorter limit is the controlling one and Kelvin held to less than 24 million years for the earth's age. More recently, the author has taken some clues from theoretical work by Sir Horace Lamb, some extensive observational data, assumed a reasonable constraint on the upper limit of the earth's magnetic field, and the laws of electromagnetism to arrive at an age of the earth's magnet of less than 10,000 years. Since there is no known geophysical means for starting up such a huge magnet in the earth within that period, one also concludes that the age of the earth itself is less than 10,000 years.

III. Kelvin's First Physical Argument Against the Vast Earth-Age.

Kelvin investigated the deceleration of the earth's rate of rotation due to the energy lost through tidal currents. He showed that, if the earth had been here for 7.2 billion years, its initial rate of rotation would have been twice its present rate (the days being only 12 hours long). That would have yielded four times as much centrifugal force as at present. If, as historical geologists claim, the earth was molten in its initial state, the centrifugal force would have bulged out the mass in the equatorial region, making the earth's radius 86 kilometers greater at the equator than at the poles (the radius of the earth's sea level is presently only 21.5 kilometers greater at the equator due to the centrifugal force with its present rate of spin). Kelvin reasoned that if the earth had consolidated at that time, the land masses would have retained most of that greatly oblated shape, four times its present oblateness. As the years passed the centrifugal force would have been reduced and the oceans would have settled into two very deep basins, one at the north polar region and the other at the south polar region. The continents would in that case now be extremely high in the equatorial regions, 40 miles higher than they actually are!

Kelvin noted that, even if the earth had been molten and consolidated at some time appreciably less than a billion years ago, it would still have evidences of that centrifugal effect and its continents would run east and west around the equator rather than the present configuration of continents running more or less north and south. Today there is evidence that the earth's rate of rotation is slowing even more than the value used by Kelvin. Hence his physical argument is even stronger today. No one has ever really challenged his physics. Geologists just chose to ignore it. Nevertheless the actual configurations of the continents and seas refute "historical geology's" claim of a 4.6 billion year age for the earth. The continents stand as testimony to a recent creation of the earth, at the maximum of, not more than, say, about 500 million years old by this evidence alone.

IV. Kelvin's Second Physical Argument Against the Vast Earth-Age.

The mean surface temperature of the earth is, so far as we know, in equilibrium. The surface of the earth receives thermal energy from the sun and stars; a small amount (one part in 3000) flows up to the surface from inside the earth. The surface of the earth radiates back into space an amount equal to the sum of that thermal influx to its surface. In fact, one can compute the mean surface temperature of the earth from this known influx of heat and Stefan's law that governs the radiation from the surface.

Kelvin assumed that even if the earth's surface were originally white hot, its surface temperature would have dropped quickly to approximately the same mean temperature it has now. The reason for this rapid surface cooling is that the cooling radiation rate at the surface is, by Stefan's law, proportional to the fourth power of the temperature (in degrees Kelvin), and the crust of the earth is a very poor thermal conductor. The cooling would then progress very, very gradually inward from the surface, penetrating inch by inch deeper into the earth. When the cooling had progressed only one foot inward, there would be a large temperature gradient, the temperature changing from very hot to the relatively cool surface temperature in just one foot. As the cooling progressed to two feet inward, the temperature gradient would have decreased to roughly half the previous value, etc.

Kelvin was able to compute the temperature gradient near the surface of the earth as a function of time lapsed from its initial state. He then assembled enough data on the earth's temperature gradient to evaluate the time lapsed since the assumed initial state. His best value for the earth's age limit, found by this method, was 24 million years.

Some scientists claimed that radioactivity in the earth would alter this limit upward, but none has given any clear analysis of how much it would alter Kelvin's value. Kelvin was well aware of radioactivity, as is demonstrated by the fact that he wrote several papers on it. That did not appear to him to alter the problem at all. He was working from an actual measured thermal flux gradient and a knowledge of thermal conductivity of the crustal rocks and was still confident that he had shown that the earth's age does not exceed 24 million years.

V. Analysis of the Decay of the Earth's Magnetic Energy Sets a Shorter Limit on the Earth's Age.

The earth's magnet is vastly stronger than any man-made magnet. Its magnetic moment (the vector that denotes the strength and direction of the magnet) has a present value of 8 x 1022 ampere meter2, a huge value. Even so, this magnet was much stronger in the ages past. The decay rate of this magnet is the most remarkable worldwide geophysical decay phenomenon ever measured. The author has employed the fundamental laws of electromagnetism (Maxwell's Equation), together with a reasonable assumption about the initial state of the earth's magnet and the measured decay rate of the earth's magnetic moment, to derive a limit on the age of the earth's magnet.1 Although there is not enough space here to give the details, both the layman and scientist will find sufficient information, physics, and analysis in the monograph to verify this physical means of arriving at a limit on the age of the earth's magnet and, by inference, a limit on the age of the earth itself. The pertinent points and physical arguments are reviewed in the following portion of this paper.

There is a logical physical reason why this magnet is decaying. Its source is real electric current, freely circulating in the molten core of the earth. Like any electric current in a conductor, it expends energy. Its present rate of energy loss is 813 million watts. This loss is not being resupplied. That is evident from the decreasing value of the earth's magnetic moment and its associated magnetic energy. As is true of other sources of energy on this earth, the earth is running out of its magnetic energy.

This is a serious problem to evolutionary geologists. None of them seems willing to admit that the earth's magnetic energy is dying out, but the data and physics unequivocally show that it is dying out. A publication of the Department of Commerce2 itemizes the values of the earth's magnetic moment for the last 130 years and states that, if the decrease in the earth's magnetic moment persists, their analysis shows "that the dipole moment will vanish in A.D. 3991."

The irony of this whole problem is that its solution is a simple one when one accepts the actual physics and sees that it does imply a young earth. The gradual collapsing of the earth's magnetic field as the magnet decays is sensed in the core of the earth as a rate of change of magnetic flux through it. The process of self-induction, operating off of that rate of change of magnetic flux, generates the back electromotive force that drives the electric current in the core of the earth. This self-induction process is sufficient to explain the observed data on the decay of the earth's magnetic moment. If there were a workable dynamo down there in the core of the earth, it in fact would have to be turned off, because this self-induction process is already producing all of the six billion amperes of current flowing in the core of the earth. Any added amount from a dynamo would be contrary to the actual value of current that is known to exist in the core, and that is produced by self-induction. One thing that is certain is that self-induction can not be shut off so long as there is a decay in the strength of the magnet, as indicated by the data.

VI. Half-life of the Earth's Magnetic Energy is 700 Years.

To evaluate the magnetic moment of the earth requires the reduction of a tremendous amount of worldwide data. The data from scores of magnetic observatories around the world are collected for at least a year's continuous measurements. These data are reduced through an elaborate mathematical process to arrive at one value and direction for the earth's magnetic moment for that year. The famous mathematician and physicist, Gauss, developed the mathematics and the instrumentation, gathered the worldwide data, and made the first evaluation in 1885. Since then there have been additional evaluations every few years. We now have 130 years of actual data.

A computer analysis of these data has shown that the decay is an exponential one, as expected from the physics, and that the half-life of the magnetic moment is 1400 years. Because the energy is proportional to the square of the magnetic moment, the half-life of the magnetic energy is only half of this time, namely 700 years. This is perhaps the most meaningful value, 700-year half-life for the energy, because the energy supply is the most fundamental quantity.

VII. Deduction of 10,000-Year Age Limit on the Earth.

Knowing the half-life of the earth's magnetic moment, one may easily work backwards to set up an historical schedule of the earth's magnetic moment and of the associated magnetic field. If that is done, it will be seen that the value of the earth's magnetic field approaches that of a magnetic star if the earth's magnetic field goes back 10,000 years. But a magnetic star has a magnetic field generated by a huge nuclear power source. Surely it is reasonable to assume the constraint that the earth never had such a powerful source and, therefore, never had a magnetic field equal to that of a magnetic star. With that constraint, physics implies a limit on the age of the earth's magnet of less than 10,000 years.

Because there is no known geophysical means, within the last 10,000 years, of starting up the huge magnet in the earth, one is led to conclude that the origin of the magnet was concurrent with the creation of the earth. Hence, the earth also has an age limit of less than 10,000 years.


1. Barnes, T.G. Origin and destiny of the earth's magnetic field. I.C.R. Technical Monograph 4, Institute for Creation Res. San Diego 1973.
2. Analysis of earth's magnetic field from 1835 to 1965, Essa Tech. Rept. IER 46IES 1 U.S. Gov. Printing Office, Wash. D.C. 1967, p. 1.

* Dr. Thomas G. Barnes is Professor of Physics at the University of Texas in El Paso. He is also President of the Creation Research Society.