The Believing Brain - Michael Shermer [172]
* * *
As for Adriaan van Maanen’s data of the nebular rotations that convinced not a few astronomers that the nebular hypothesis was correct, Hubble concluded that it must have been measurement error: “The problem of reconciling the two sets of data has a certain fascination, but in spite of this I believe that the measured rotations must be abandoned. I have been examining the measures for the first time and the indications point steadily to a magnitude error as a plausible explanation. Rotation appears to be a forced interpretation.”22 A perplexed and frustrated Van Maanen went back to his astronomical plates and recrunched the numbers, telling Shapley, “I cannot find a flaw in M33, for which I have the best material. They seem to be as consistent as possibly can be.” Shapley countered with a diplomatic comparison between two sets of data and corresponding theories: “I am completely at a loss to know what to believe concerning those angular motions; but there seems to be no way of doubting the Cepheids, providing Hubble’s period-luminosity curves are as definite as we hear they are.”
They were, and years later when Shapley was asked in an interview why he defended Van Maanen’s rotational data for so long, he responded in the third person: “They wonder why Shapley made this blunder. The point … is that Van Maanen was his friend and he believed in friends.” An admirable trait to be sure, which can even cloud the judgment of data-hardened scientists, but in the end data and theory must trump belief and friendship.
* * *
The great debate over the celestial nebulae serves as a classic study in the history of science demonstrating that, in time, disputes are settled and debates are resolved through higher-quality data and more comprehensive theory. Perhaps science does not progress as quickly as we might like, and scientists often cling to cherished theories long after the data indicates that they should (especially when yoked to friendship), but eventually change does come, paradigm shifts are made, revolutions are undertaken, and cumulative progress is made toward a greater understanding of the true nature of nature.
Where do we go from the island universe theory? What can there be beyond island galaxies populating an expanding universe?
Science and the Greatest Unsolved Mystery
There is one mystery I will concede has proven to be a knotty one for science, and that is the matter of how our universe came to be. The mystery is presented in two general ways, one impossible to answer and the other potentially (but not yet) answerable. In the first configuration, the question is asked, What existed before our universe began? Or Why is there something rather than nothing?
Phrasing the questions in this way is not only unscientific, it is nonsensical, along the lines of asking What time was it before time began? Or What is north of the North Pole? Asking why there is something rather than nothing presumes “nothing” is the natural state of things out of which “something” needs an explanation. Maybe “something” is the natural state of things and “nothing” would be the mystery to be solved. As the physicist Victor Stenger noted: “Current cosmology suggests that no laws of physics were violated in bringing the universe into existence. The laws of physics themselves are shown to correspond to what one would expect if the universe appeared from nothing. There is something rather than nothing because something is more stable.”23
The theist’s answer to the problem of existence is that God existed before the universe and subsequently brought it into existence out of nothing (ex nihilo) in a single creation moment as described in Genesis. But the very conception of God existing before the universe and then creating it implies a time sequence. In both the religious and scientific worldviews, time began with the big bang creation of the universe, so God would