Frames of Reference

What’s this all about? About AD 1900 scientists thought everything had been figured out, that there was little else to do. Sure, some details had to be filled in, but for the most part, we understood the world around us. Then along comes this Einstein guy and messes up the whole thing! Einstein is famous for two basic things - Relativity and Quantum Physics - plunging scientists into a world of doubt and uncertainty. Let’s look at one of these two (Relativity) and see why it troubles people so. The other (Quantum Physics) is extremely interesting in it’s own right, but is a subject for another time (no pun intended!).

First, consider the following diagram (I’ll explain it in a moment), and remember, there will only be one line of Physics in the following discussion, so if you are of the type thinking “I can’t understand physics stuff”, hang on.


First, consider you and a friend are riding motorcycles, represented by A and B. You are traveling from point A to point A’ at 1/2 the speed of light, or c/2. At point A you shine a flashlight toward your friend, at point B. (Notice the picture is not to scale).

Now, from your point of view, neither of you is moving since your speed is the same. This is familiar to anyone who has ridden in a car. If someone pulls up alongside you as you are traveling down the road, if they match your speed, it appears to both of you as if you are both sitting still in a parking lot. In either case, both you and your friend see the light travel along the path noted by d. For you both, your forward motion is irrelevant to your perception of the event.

Now, consider someone standing along side the road, watching you both go by. Since you and your friend are moving, they see you travel from A to A’. What path would the light take to them? Looking at the picture above, the answer is d’. This should also be familiar to anyone who has ridden in a car. Imagine throwing a ball out the window of a moving car. Since the car is moving, as you throw the ball, it still travels forward as it falls, doesn’t it?

Before we continue, be sure you understand the diagram and the previous two paragraphs. Neither assume any understanding of relativity or physics, just some recalling of your experiences, however, they are critical to understand before continuing.

OK, now the fun begins! Once again, we must recall some of our experiences. Suppose you are traveling in a car at 60mph for 1/2 hour. How far have you traveled? How do you know? The answer is the following equation: d = v * t . Your distance traveled is equal to your speed multiplied by the time. Thus 60mph * 1/2 hour = 30 miles. But you already knew this. (See, you know much more about physics than you thought!) Perhaps you did not know the equation, but once again, anyone who has traveled in a car has experienced this.

Now, lets apply the previous equation to our paths d and d’ above. Then we thus have d = v * t and d’ = v’ * t’. Fair enough? (Remember, d,v,t are for you and your friend riding the motorcycles, and d’,v’,t’ are for your friend watching you go by). Notice by looking at the picture, that d’>d. In the interest of completeness, I shall now prove to you that d’>d. For readers who to not wish to proceed in mathematical exactness, skip the following paragraph.

For all the mathematical details, see the PDF format; a link is available at the end of this article.

Now, let’s look at all we know:

  • d = v * t
  • d’ = v’ *t’
  • d’ > d

Combining these equations (using a little algebra) yields the following inequality v’ * t’ > v * t

OK, I promised only one line of real physics, and here it is:

Every observer measures the same value c for the speed of light Tipler, Physics, Third Edition Volume 2, page 1107

Now, that wasn’t so bad, was it? This was Einstein’s proposal. Simply put, it just means the speed of light is constant. What does that mean for our little example? That v’ = v = c. Thus, our inequality becomes c * t’ > c * t. Once again, using algebra to simplify yields the following shocking result:

t’ > t

Now, remember what t represents, time. This means for our observer watching us go by, their time is longer. Does this mean for our friends on motorcycles they experience a “slowdown” of time? NO! If we take two atomic clocks (extremely accurate) and place one on a motorcycle, put the other with the person standing along the road, synchronize them, then let the motorcycles ride by, when they come back we notice the clocks are no longer synchronized! It is the very nature of time itself that has changed, not the accuracy of the clocks.

OK, so you understand a little about relativity - what does this have to do with the Bible? Consider the following:

But, beloved, do not forget this one thing, that with the Lord one day is as a thousand years, and a thousand years as one day (2 Peter 3:8 NKJV).

This is exactly what relativity is all about - time is not absolute, it can vary depending on mass, acceleration and gravity. Relativity is a recent discovery (1900’s), so how would Peter have known about it thousands of years ago? Only by inspiration of the Holy Spirit. The Bible is the Word of God.

This article available as PDF Download.

Filed Under: Science

Recommended Citation:
Yeager, Darrin "Frames of Reference" (2024-05-19 17:20),
Copyright 1998–2024. All rights reserved.

Copyright ©Frames of Reference LLC 1998–2024