Hubble Constant and Age of the Universe

The Associated Press released an article on Friday, September 13, 2019, that read, “Study Finds the Universe Might be Several Billion Years Younger.” The news story sites a study released in the journal Science on September 12. In the study, Inh Jee of the Max Planck Institute in Germany used a new method to measure the Hubble Constant, which scientists use to calculate the age of the universe.

Right away, we have seen some fundamentalists jumping to the conclusion that the headline means the Earth is 6,000 years old after all. The Bible doesn’t tell us how old the creation is. The age of the Earth is a denominational issue for those whose human doctrines won’t work if the Earth is more than 6,000 years old. Our concern is that people understand that this is not an issue about whether God exists or whether the Bible is true.

We can measure the age of the universe by determining the expansion rate of the cosmos, which is the Hubble Constant. Measuring that expansion has been incredibly difficult, and that is what the headline refers to. In previous years the Hubble Constant has been estimated to be 70. Inh Lee and her team used a new technique called time delay gravitational lensing which gave a value for the Hubble Constant of 82.4. That would reduce the age of the universe from the currently accepted 13.7 billion years to 11.4 billion years. Other scientists using other techniques earlier this year have given a Hubble Constant of 74 and 73.3. Previous methods have given a value as low as 67. A lower value means an older universe, and a higher value of the Hubble Constant means a younger universe.

If you know the value of the Hubble Constant, the calculation of the age of the universe is very simple. We all know that travel time depends on two things. If I go 100 miles at 50 miles per hour, how long did I travel? The obvious answer is two hours. Distance traveled is equal to the speed at which you travel multiplied by how long you travel at that speed. We can measure the size of the cosmos by several techniques. Triangulation is difficult because the size is so huge that the apex angle of the triangle is too small to measure accurately. However, triangulation does give us an idea of the vastness of space.

The further light travels through the cosmos, the lower the frequency of the light. That effect is caused by dust particles in space scattering the higher frequency blue light. The effect is called interstellar reddening, and it gives us a good measure of the size of the cosmos. Several other methods involve complex energy production by various stars. All of those methods provide a reasonably consistent measure as to how big the cosmos is. Applying the Hubble Constant to the size of the cosmos provides us with a measure of the age of the universe.

The point of all of this is to get values that science can use to study astronomical processes in deep space. The problem is that our measuring devices are primitive in terms of what we need for such distant objects. What it means to those of us who marvel at the size and complexity of space is that more than ever, “The Heavens declare the glory of God and the firmament shows His handiwork” (Psalms 19:1).
— John N. Clayton ©2019