Gravitational Lens Measurements Yield New Cosmic Creation Test
The heart and soul of the biblical cosmic creation model calls for continual cosmic expansion under fixed physical laws from an actual beginning of matter, energy, space, and time.
For over two thousand years the Bible stood alone as the only text making such claims about the universe. Not until Albert Einstein produced his theory of general relativity in 1916 did scientists even consider the possibility of continual cosmic expansion. Thus, any effort to confirm to a greater degree continual cosmic expansion from a transcendent cosmic creation event not only establishes the validity of the biblical cosmic creation model, but it also demonstrates the Bible’s capacity to accurately predict future scientific discoveries.
Recently, a paper published in the Astrophysical Journal provided additional evidence for the biblical cosmic creation model and demonstrated how ongoing observational efforts will lead to even stronger support. This paper shows how new observations allow an accurate determination of the expansion history of the universe without reliance on the “distance ladder.” These new observations take advantage of time delays between multiple images of strong gravitational lens systems.
An example of a strong gravitational lens system is where a round galaxy is situated in the line of sight between an observer’s telescope and a distant quasar. Einstein’s theory of general relativity states that the round galaxy will act as a lens, bending the light from the distant quasar. If the galaxy is exactly in the line of sight, the image of the quasar will be transformed from its actual point image into a small ring. In the much more common case where the galaxy is slightly off the line of sight, the quasar’s point image becomes lensed into two or more point images.
Almost all quasars experience frequent and large variations in their light output. Such variations allow astronomers to determine how rapidly the universe expands at the epoch corresponding to the light-travel time to the quasar. A variation in the light output of the quasar will also show up in the lensed image of the quasar. But, typically, different parts of the lens will be situated at different distances relative to the observer. Those different distances mean that the light will arrive at the observer’s telescope at different times. Knowing the velocity of light, astronomers can translate the different times into distance differentials in kilometers. The measured angles separating the different components of the lens allow astronomers to use junior-high plane geometry theorems to determine the distance to the lens in kilometers. Measuring the redshift of the spectral lines in the lensed image tells astronomers how rapidly the lens is moving away from us. In this manner astronomers can use gravitational lenses over a wide variety of cosmic distances to determine how rapidly the universe expands at different distances relative to Earth.
Until recently, astronomers lacked an adequate number of accurately measured strong gravitational lens systems for them to reliably determine the expansion history of the universe. Now, Masamune Oguri, an astronomer at Stanford University, analyzed 16 published time-delay quasars and produced the first-ever accurate determination of the expansion rate of the universe without any reliance on the assumptions inherent in the distance ladder approach. His measurement of the cosmic expansion rate, also known as the Hubble constant, was 70 ± 6 kilometers per second, per megaparsec (228 ± 20 kilometers per second, per million light years). The value determined through the distance ladder method is 72 ± 8 kilometers per second, per megaparsec (235 ± 26 kilometers per second, per million light years)1.
The remarkable agreement between the two independent methods demonstrates that the confidence astronomers express in their determination of the expansion history of the universe is justified. The agreement also confirms that the assumptions undergirding the distance ladder method are valid.
Christians and non-Christians alike can be assured that what the Bible has been teaching about the origin and history of the universe for over two thousand years is correct. They can rest assured also in the conclusion that continual cosmic expansion implies a beginning which in turn implies a Beginner. Christians can rejoice, too, in how this discovery helps resolve the debate over the age of the universe. If the universe continually expands under constant laws of physics from a cosmic creation event, as the Bible states, then a reliable measurement of the expansion rate will yield a reliable measure of the universe’s age. A measure of 71 kilometers per second, per megaparsec implies a cosmic age of about 14 billion years.
Endnotes
- Wendy L. Freedman et al., “Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant,” Astrophysical Journal 553 (2001): 47-72.