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About the Book
Table of Contents
Part I
Part II
Part III
Part IV
Part V
Part VI
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Time and Eternity:Creation and the
Theory of Relativity
Chapter 1
Historical Background
IT WILL BE convenient
in this study to consider the matter under two headings, one
of which is strictly in the realm of physics and the other in
the realm of philosophy. The first is the relativity of
time, and the second is its co-existence with the created
order. Or to put it a little more elaborately, the first consideration
is how fast time really goes and whether it has a fixed speed
independently of experience. And the second consideration is
what happens to experience in the total absence of time. The
first question involves us in a brief historical review which
will prepare the way for a survey of some important passages
of Scripture that involve the second.
In spite of what has been said
above about the dangers of using analogies, even a historical
sketch of this subject has to depend to a large extent upon analogy.
It used to be thought that light was, as it were, instantaneous.
No sooner did a man switch on his flashlight than the beam hit
the wall. But in the seventeenth century, an astronomer named
Ole Roemer (1644-1710) found that eclipses to the moons of Jupiter
occurred sixteen minutes earlier when Jupiter and the earth were
on the same side of the sun than when on opposite sides. He rightly
concluded that light was not instantaneous. The difference in
distance between the earth and Jupiter in the two situations
made the light late in arriving, for it was actually taking time
for it to travel over the intervening gap. He calculated that
the moons circling the planet took so many hours to travel round
once, thus establishing a regular time cycle for eclipses. These
eclipses could then be clocked, and by projecting the time interval,
could thenceforth be guaranteed to occur regularly over any number
of years providing it did not slow down.
However, it was found that when
the planet Jupiter was on the other side of the sun from the
earth, the time sequence was thrown out and the eclipses were
sixteen minutes late. Sixteen minutes is 960
 pg
1 of 6 
seconds. The orbit of
the planet gave the difference in the distance when on the same
and on the opposite side of the sun. This distance divided by
960 revealed that the speed of light must be approximately 186,000
miles per second. His discoveries were published posthumously
in 1735. Subsequent experiments gave a more accurate figure of
186,319 miles per second
This discovery was very quickly
seen to be the possible answer to another question which had
been troubling astronomers for some time. This question had to
do with the speed of the earth through the supposed ether. And
this second question took a form something like this: because
light and heat reached the earth from the sun, it was assumed
that some kind of medium existed to convey the waves. However,
if this medium had any kind of "substance," it seemed
obvious that the earth would burn up as it raced through it in
its circuit around the sun. The problem was to find a medium
real enough to convey waves, but thin enough to offer no resistance
to the passage of a body through it.
But this contingency led to a further
question: Was this medium stationary with respect to the universe,
pervading it uniformly in every part of it, like a sea in which
the stars plowed their way? In which case the actual speed of
the earth relative to the universe and to all other moving bodies
in it ought to be discoverable. To determine this was very desirable.
Our sun with all the other stars appears to be rushing madly
outward as the universe expands. This assumption is based on
certain observations which we do not need to enter into here;
it is sufficient to say that the distance between other galaxies
and our own seems to be increasing as the periphery of the universe
is enlarged. However, this increase in distance could mean that
we might be chasing these remote galaxies but losing in the race,
like a dog chasing a car. Or they may really be chasing us while
we make our escape. All that we know about it is that the distance
between these systems appears to be growing gradually greater.
But if the ether is stationary, it would be possible to discover
who was chasing whom, and absolute motions could be calculated
A man who strolls the deck of a
modern liner may be travelling relative to the vessel at two
miles per hour. If the boat is at rest on the St. Lawrence, this
is his absolute motion and direction with reference to the river.
If the boat begins to move at 15 knots, the whole problem changes.
His speed relative to the boat is still 2 m.p.h., but to the
river may be 13 or 17 knots depending on the direction of his
walk. If he happens to be crossing the boat from side to side,
his motion relative to the river is 15 knots one way and 2 m.p.h.
in a
pg.2
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perpendicular direction.
When the current of the river is taken into account, all these
speeds are affected and altered relative to the shore and unless
he is in sight of some object on the shore which he knows to
be stationary, he can never determine his actual speed with respect
to the earth itself. But when the motion of the earth around
the sun and the sun among the stars has also to be considered,
his absolute motion becomes exceedingly difficult to determine,
because there is no fixed point on the "shoreline"
of space by which it can be gauged. It had been hoped that the
ether might provide this gauge.
If we know that a wind is passing
us at 60 m.p.h. and we have a wind gauge in our hands, we can
from this knowledge discover our own speed. If the wind gauge
indicates a higher figure, it is because we are travelling toward
it. If the reverse, the opposite is the case. If there is no
difference, we are probably stationary. We need to know only
that the wind is passing us at a uniform speed, and the measurement
of all subsequent movement is possible, given enough instruments.
Every effort to demonstrate the
reality of the ether had failed, and we therefore had no "sea"
through which the earth was passing with all the other stars
which could serve as a basis for establishing absolute movement.
But suddenly it appeared that a new yardstick had been provided
by Roemer's discovery. Without going into too many details, it
seemed obvious that light passing through a current of ether
would be either accelerated or slowed up if such a fluid medium
did in fact exist to create a current, depending on which way
the light was travelling.
The history of the experiments
which were at once undertaken to test this hypothesis is now
probably quite familiar. The most famous investigation has since
been known as the Michelson-Morley Experiment, and it was the
findings of these two scientists which led Einstein in 1905 to
formulate the first two principles of his Special Theory of Relativity.
The historical background has been given clearly and accurately
by R. S. Shankland in the British Journal Nature. (3)
A. A. Michelson was born December
19, 1852, in Strelno, Germany. When he was two years old, the
family moved to California. In 1869 he entered the U.S. Naval
Academy at Annapolis. Here, in 1877, he made his first measurements
of the speed of light and subsequently in 1880, while at the
College de France, invented the Michelson Interferometer as a
means for measuring the earth's motion through the ether. His
interest in this problem had been
3. Shankland. R. S., "Michelson, A. A.,
1852-1931," in Nature, vol.171, 17 Jan., 1953,
p.101 ff.
pg.3
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aroused by a letter from
James Clark Maxwell, who emphasized that all experiments to observe
the earth's motion through the ether, which depended on measuring
the first power of the ratio of the earth's speed to that of
light, were doomed to failure. He said, in effect, that no terrestrial
experiment for measuring the velocity of light could ever detect
the earth's motion in space. This was a challenge to Michelson.
His first experiment was made in Helmholtz's laboratory in the
University of Berlin. Both this and a second trial in 1881 gave
a null result, although Michelson himself never considered it
conclusive.
In 1882 Michelson returned to Cleveland
and made further measurements on the speed of light, obtaining
a value of 299,853 plus or minus 60 kilometers per second, the
most reliable measure until 1927. He subsequently met Edward
W. Morley while attending a series of lectures by Lord Kelvin,
and the two men collaborated in further experiments, using more
refined methods.
In 1886 Michelson and Morley together
undertook the investigation which has since been known as the
Michelson-Morley Experiment. All kinds of precautions were taken
to render any results obtained absolutely conclusive. As Shankland
put it: (4)
The work with this apparatus
continued from 1886 until July 1887 and was conducted in buildings
on the adjacent Case and Western campuses. The definitive null
result obtained in these experiments led to profound changes
in the development of Physics. . . . It is needless
to say that the most direct and now universally accepted explanation
for the Michelson-Morley Experiment . . . is provided by the
Special Theory of Relativity given by Albert Einstein in 1905.
J. W. N. Sullivan
has summarized the significance of these events. (5)
Since then the Michelson-Morley
Experiment has been repeated many times. In principle it is very
simple, and consists in comparing the velocity of light in different
directions. If the earth is moving through a stationary ether,
it can be shown that two rays of light, the one moving in the
direction of the earth's motion, and the other at right angles
to it, should take unequal times to cover the same distance.
But although the experiment has often been repeated, no difference
has ever been found, although in some of these experiments the
apparatus has been so delicate that a difference one hundred
times less than the difference expected could have been measured.
. . .
The dilemma thus created is a very
real one and the way out, which was shown by Einstein in 1907,
is an effort of genius of the highest order. . . . Einstein
asserted that the velocity of light is always the same whether
we measure this velocity from a system which is in motion or
a system which is at rest.
4. Ibid., p.102.
5. Sullivan, J. W. N., Limitations of Science, Pelican,
London, 1938, p.69.
pg.4
of 6
It
often happens in the history of science that an effort to prove
a theory fails in its immediate objective but leads by accident
to a much more important truth. This was so in the case of the
Michelson-Morley Experiment: it led ultimately to the discovery
that light impacts an object at a uniform velocity regardless
of whether the object is moving toward or away from the source
of light at any speed less than the speed of light. Einstein's
principle of constancy means that light rays if unobstructed
have an observed constant velocity irrespective of the relative
velocity between the observer and the source of light. Or to
put it slightly more dramatically in the words of William Hudgings:
(6)
Einstein's declaration is that
if two observers are on the opposite sides of the rotating earth,
one revolving away from the sun and the other toward it, the
instruments of each observer will indicate that the rays from
the flash are travelling past him at exactly the same speed of
186,000 miles per second regardless of whether he is travelling
towards or away from the sun.
As it stands,
this seems like an impossibility.
With profound insight, Einstein
had pointed out in so many words that while the speed of impact
of the light must logically be different, it could not be measured
because the rate of flux of time was changing in such a way as
to conceal any difference in the two velocities being measured,
and time is a basic function of velocity. It is as though two
watches keeping different time, one faster than the other, were
being employed in this one experiment, the one watch for the
speed of light in one direction and another watch for the speed
of light in the other direction, so that by taking into account
the difference in the time intervals shown by the two watches
which were not synchronized together, the logical contradiction
could be explained. The question then arises which of the two
watches was keeping "correct" time. Einstein's answer
is "both" and "neither": there is no such
thing as correct time in the sense of Absolute Time. The passage
of time is entirely relative, and its rate of flow is established
by each observer in each situation for himself -- quite unconsciously.
In some way, Nature has contrived � sometimes the word conspired
is used � to make it impossible to discover any absolute
passage of time.
However, in any given situation
there is a measurable flow of time which makes possible
the measurement of distance or volume or speed for that particular
situation. Time therefore becomes the
6. Hudgings, W. F., An Introduction to
Einstein's Theory of Relativity, Haldiman-Julius, Girard,
Kansas, 1923, p.23.
pg.5
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fourth dimension of all
measurements taken within the framework of the physical universe.
Without time no thing exists, and without things time has absolutely
no meaning. This brings us in a circle, back once again to the
observation made by Einstein which we have already quoted: (7)
If you don't take my words too
seriously, I would say this. If we assume that all matter would
disappear from the world, then, before relativity, one believed
that space and time would continue existing in an empty world.
But according to the theory of relativity, if matter and its
motion disappeared there would no longer be any space or time.
One is reminded
of the profound insight of Augustine, that time began with Creation.
Or, to use his own words, "Beyond doubt, the world was made
not in Time, but together with Time." (8)
As Sullivan says, Nature knows
nothing of the distinction we make between space and time. The
distinction we make is due to a psychological peculiarity of
our own minds. This brings us to one consideration which is a
little difficult to deal with because it is very easy to confuse
the physical aspects of the Theory of Relativity with the psychological
aspects. And these in turn have to be distinguished from what,
for want of a better term, we can only refer to as the spiritual
aspects. So we turn, first, to psychology and the realm of experience.
7. Einstein: quoted by Philipp Frank, Einstein:
His Life and Times, Knopf, New York, 1947, p.178
8. Augustine: De Civitate Deo, Book 11, chapter 6
pg.6
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Copyright © 1988 Evelyn White. All rights
reserved
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