Fine-Tuning the Case for Fine-Tuning: a Cosmic Breakthrough

by Hugh Ross

Lawrence Krauss, at Case Western Reserve University in Ohio, unabashedly acknowledged in the Astrophysical Journal (July 10, 1998) a forward leap in the case for a "designed" rather than accidental cosmos. His efforts to refine our understanding of the universe's expansion have significantly advanced modern cosmology and, at the same time, have contributed substantially to the Christian's argument for the biblical Creator.

To review developments in this area of research, you may wish to look back into the first quarter 1998 issue of Facts & Faith. In an article about the big bang, I reported on the latest of efforts to determine whether or not the universe is "open," i.e., forever expanding, "flat," i.e., perfectly balanced between expanding and collapsing, or "flat with the help of a phenomenon called the cosmological constant. (The "closed," or collapsing, universe is essentially a "closed" question.)

The theological implications are these: 1) If the universe is open, only the involvement of an intelligent designer could fix and hold the expansion at just the right rate to permit life. 2) If the universe is flat, the need for design is less obvious at best, obscure at worst. 3) If the universe is flat but held flat by the precisely fixed effect of a cosmological constant, again the need for a divine designer becomes clear.

The key factors determining whether the universe is open, closed, flat, or flat with help are these: the mass density of the universe, the expansion rate of the universe, and the value of the cosmological constant. (Such a constant, first postulated by Albert Einstein, describes a force that, if it exists, would cause space and hence the universe itself to expand more and more rapidly through time.) Measuring and calibrating these factors will, of course, help narrow down the cosmic creation date.1 Vice versa, zeroing in on the creation date, from whatever angle, will tell us something about these factors.

Since the beginning of this year, researchers have worked assiduously to produce and analyze data that would yield answers. An international team, the High-z Supernova Search Team, investigating distant, type Ia supernovae (huge star explosions) discovered some indications of a small cosmological constant.2 Their findings rest, however, on the assumption that the universe is perfectly uniform and homogeneous, non-rotating and without distortions, but we know it is somewhat clumpy.3-4

Krauss and his colleagues tried a different approach.5 Using measurements coming from the Hipparcos satellite,6 he recalibrated the distances to seventeen globular clusters in our galaxy. These distances to the oldest stars in the universe have been the greatest source of uncertainty in calculating the universe’s age. Their figures yielded an age of 13.0±1.3 billion years,7 nearly 2 billion years younger than pre-Hipparcos measures suggested. This age figure coincides with the most recent measurements made by California Institute of Technology and University of Washington astronomers on 150 globular clusters in the supergiant galaxy M87. These researchers determined a creation date of 13.5±2.0 billion years.8 These two sets of data are also consistent with the latest research on the Hubble constant (the expansion rate of the universe and, thus, an age indicator). The most recent Hubble estimate for the creation date is 13.7±2.5 billion years.9

Kraus carried his inquiry still further. Integrating the latest measurements of the quantity of ordinary matter and exotic matter in the universe with a German team's calculation of the mass density of the universe,10 Krauss has virtually ruled out the possibility that the universe is flat with a zero-valued cosmological constant. That is, the universe either is open, having only about one-third of the mass necessary to halt its expansion, or it is flat and held flat by a small cosmological constant.

Of these two possibilities, the data accumulated thus far slightly favor an open universe with a zero cosmological constant while certain theoretical considerations within particle physics favor a flat universe with a just-right cosmological constant. Krauss has succeeded in ruling out one model, narrowing the field from three to two.

As Krauss himself points out, each of the two models left requires a high degree of fine tuning. A universe with a cosmological constant "involves a fine-tuning of over 120 orders of magnitude" while an open universe without a cosmological constant still "involves a fine-tuning of perhaps 60 orders of magnitude."11 In other words, if our universe has a cosmological constant, the value of that constant can vary no more than one part in 10120 (the number one with 120 zeros after it). If it has no cosmological constant, its expansion rate must be fined-tuned to within one part in 1060. For the sake of comparison, the best example of human fine tuning is the gravity wave detector currently under construction, fine tuned to one part in 1023. Human achievement takes on a new perspective in light of such numbers. For that matter, so does divine power.

1.Hugh Ross, "Big Bang Gets New Adjectives—Open and Hot," Facts & Faith, v. 12, n. 1 (1998), pp. 4-5.
2.James Glanz, "Astronomers See a Cosmic Antigravity Force at Work" Science, 279 (1998), pp. 1298-1299.
3.Richard C. Tolman and Morgan Ward, "On the Behavior of Non-Static Models of the Universe When the Cosmological Term is Omitted," Physical Review, 39 (1932), p. 842.
4.John D. Barrow and Joseph Silk, The Left Hand of Creation: The Origin and Evolution of the Expanding Universe (New York: Basic Books, 1983), p. 32.
5.Lawrence M. Krauss, "The End of the Age Problem, and the Case for a Cosmological Constant Revisited," Astrophysical Journal, 501 (1998), pp. 461-466.
6.Hugh Ross, "New Telescope Refines Cosmic Distance Measures," Facts & Faith, v. 11, n. 2 (1998), pp. 3-4.
7.Lawrence M. Krauss, p. 462.
8.Judith G. Cohen, John P. Blakeslee, and Anton Ryshov, "The Ages and Abundances of a Large Sample of M87 Globular Clusters,” Astrophysical Journal, 496 (1998), pp. 808-826.
9.Lawrence M. Krauss, p. 462.
10.Peter Schuecker, et al, "The Muenster Redshift Project. III. Observational Constraints on the Deceleration Parameter," Astrophysical Journal, 496 (1998), pp. 635-647.
11.Lawrence M. Krauss, p. 465.

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