Monday, June 23, 2014

An excellent interview on scientific cosmology, fine-tuning, and theism

by Salman Hameed

There are different types of God-of-the-gap arguments, and I think fine-tuning argument is the latest fad. I have argued before that science should be left as science - even when it comes to the questions of the origins of the universe. One of the key reasons is that we don't know where the boundaries of our knowledge lie. If history of science is any guide, several of the unsolvable problems got solved with the passage of time. From that perspective, it might be useful to keep faith/religion separated from science - and definitely from religion seeking any validation from science. All of this still leaves the room for the ultimate "why" question - and that depends on faith (both for a theistic and atheistic positions).

In this context, here is a non-nonsense interview with philosopher of science, Tim Maudlin, on modern cosmology and God. You should read the full interview, but I will highlight a few items of interest. He starts with the implication of modern cosmology for theology so far:
Gary Gutting: Could you begin by noting aspects of recent scientific cosmology that are particularly relevant to theological questions? 
Tim Maudlin: That depends on the given theological account. The biblical account of the origin of the cosmos in Genesis, for example, posits that a god created the physical
universe particularly with human beings in mind, and so unsurprisingly placed the Earth at the center of creation. 
Modern cosmological knowledge has refuted such an account. We are living in the golden age of cosmology: More has been discovered about the large-scale structure and history of the visible cosmos in the last 20 years than in the whole of prior human history. We now have precise knowledge of the distribution of galaxies and know that ours is nowhere near the center of the universe, just as we know that our planetary system has no privileged place among the billions of such systems in our galaxy and that Earth is not even at the center of our planetary system. We also know that the Big Bang, the beginning of our universe, occurred about 13.7 billion years ago, whereas Earth didn’t even exist until about 10 billion years later. 
No one looking at the vast extent of the universe and the completely random location of homo sapiens within it (in both space and time) could seriously maintain that the whole thing was intentionally created for us. This realization began with Galileo, and has only intensified ever since. 
G.G.: I don’t see why the extent of the universe and our nonprivileged spatio-temporal position within it says anything about whether we have some special role in the universe. The major monotheistic religions maintain that there is a special spiritual relationship between us and the creator. But that doesn’t imply that this is the only purpose of the universe or that we’re the only creatures with a special relationship to the creator. 
T.M.: Yes, of course, there are, in theory, other possible hypotheses about the origin of the universe and our role in it. Someone might hold that the universe was created with humans playing some important role, but a role equally played by other living beings (not living on Earth); or that the universe was created with some living beings playing an important role, but that humans are not among them; or even that the universe was created with no particular regard for any living beings. 
If cosmology is to bear on any such hypothesis, then the hypothesis must lead to some expectations for the sort of universe a deity so motivated would create. The expectations following from the accounts, like Genesis, that make us the main purpose of the universe have, as I’ve pointed out, the great weight of evidence against them. (The other sorts of hypotheses have not been much advocated to my knowledge, and hence not developed to the point where one would know what sort of a physical universe to expect if any of them were true. My guess is that most religious people would not be especially interested in these hypotheses.)
Here is the second part of the conversation about the possibility of deriving theology from fine-tuning arguments, which Maudlin disagrees with:
G.G.: So are you saying that we don’t know enough about the relevant constants to get a theistic argument started? 
T.M.: Yes, since we don’t even know if the “constants” are constant, we certainly don’t know enough to draw any conclusions about the best account of why they have the particular values they have right now and around here. Since we don’t know how the various “constants” might be related to each other by deeper physics, the game of trying to figure out the effect of changing just one and leaving the rest alone also is not well founded. 
One thing is for sure: If there were some deity who desired that we know of its existence, there would be simple, clear ways to convey that information. I would say that any theistic argument that starts with the constants of nature cannot end with a deity who is interested in us knowing of its existence. 
G.G.: Once again, that’s assuming we are good judges of how the deity would behave. But suppose that a surprisingly narrow range of the relevant constants turns out to be necessary for humans to exist. Some critics would say that even so, cosmological inflation would provide a satisfactory explanation with no reference to a creator. What’s your view on that? 
T.M.: Not everything about cosmology is known. We do not know how to reconcile quantum theory and relativity yet, and such a reconciliation would be needed to investigate the nature of the Big Bang. In particular, we don’t understand the basic physics well enough to tell if anything preceded the Big Bang. Even the existence of an inflationary period is still controversial. 
One very speculative idea in cosmology is that the entire universe contains infinitely many “pocket universes” or “bubble universes,” in each of which the quantities we call “constants of nature” take different, randomly chosen, values. If so, then every possible combination of such values occurs somewhere, and living beings will obviously only evolve in regions where the combination of values supports life. Such an account predicts that intelligent creatures would arise in essentially random locations in a huge cosmological structure, just as we see. But this idea is highly speculative, and there is no direct evidence in its favor. 
G.G.: So is your view that we don’t currently know enough to decide whether or not fine-tuning for human life supports theism? 
T.M.: First, note how “humans” got put into that question! If there were any argument like this to be made, it would go through equally well for cockroaches. They, too, can only exist in certain physical conditions. The attempt to put homo sapiens at the center of this discussion is a reflection of our egocentrism, and has no basis at all in the actual structure of the universe. 
Consider a different hypothesis. Suppose that there is a deity who created the universe with particular attention to the fate of some creatures in a distant galaxy. The very existence of the Earth and the evolution of life on Earth was just an unintended byproduct of setting up the “constants of nature” for the sake of those creatures, not us. That would be a fascinating thing to find out, but not what most people with interests in theism were after. The actual values of the “constants of nature” certainly cannot provide more evidence for their (Genesis-like) hypothesis than for this hypothesis.
And two other important things. Maudlin corrects misconception that Lawrence Krauss provided an explanation of how universe came out of nothing (even though Krauss used that in his title) and points out the flaw in that strategy:
G.G.: Finally, let me ask about what I’ve called causal theism, which merely argues that a creator is needed to explain the very existence of the universe, regardless of its purpose. Some cosmologists, like Lawrence Krauss, have suggested that current physical theory shows how the universe could have emerged from nothing — for example, by a quantum fluctuation. What do you think of this suggestion? 
T.M.: The more general claim that a creator is needed to explain the very existence of the universe is a much, much weaker claim, and is consistent with humanity having had no particular significance at all to the creator. That’s why I say that just getting some creator or other is not what most people are after. 
In any case, does there need to be a nonmaterial cause as an explanation for the entire material universe? Causal explanation either goes on forever backward in time or it comes to a stop somewhere. Even people who want to postulate a nonmaterial cause of the material universe often see no need to invoke yet another cause for that nonmaterial cause, and so are content to let the sequence of causal explanations come to an end. But the initial state of the universe (if there is one) could just as well be the uncaused cause. Or if there is no initial state, and the universe goes back infinitely in time, then it can’t have a cause that precedes it in time. 
Krauss does not suggest that the universe came to exist “from nothing” in the sense of “did not come from anything at all,” but rather that it came from a quantum vacuum state. He seems to think that such a vacuum state would be a satisfying place to end the causal regress as the state with no causal antecedent. The vacuum state has many important symmetries, so if one could tell a physical story of everything coming out of a vacuum state it would have a certain appealing plausibility. But one could still ask, “Why start with the vacuum state rather than something else?” I think we don’t know enough to make any plausible guess about even whether there was an initial state, much less what it might have been. This goes beyond what we have good evidence or theory for.
And what about a minimalist theistic view - at least from a scientific perspective?
G.G.: You obviously don’t see scientific cosmology as supporting any case for theism. You also think that it refutes theistic religions’ claiming that the primary purpose of God’s creation is the existence of human beings. What, finally, is your view about the minimal theistic view that the universe was created by an intelligent being (regardless of its purpose). Does scientific cosmology support the atheistic position that there is no such creator or does it leave us with the agnostic judgment that there isn’t sufficient evidence to say? 
T.M.: Atheism is the default position in any scientific inquiry, just as a-quarkism or a-neutrinoism was. That is, any entity has to earn its admission into a scientific account either via direct evidence for its existence or because it plays some fundamental explanatory role. Before the theoretical need for neutrinos was appreciated (to preserve the conservation of energy) and then later experimental detection was made, they were not part of the accepted physical account of the world. To say physicists in 1900 were “agnostic” about neutrinos sounds wrong: they just did not believe there were such things. 
As yet, there is no direct experimental evidence of a deity, and in order for the postulation of a deity to play an explanatory role there would have to be a lot of detail about how it would act. If, as you have suggested, we are not “good judges of how the deity would behave,” then such an unknown and unpredictable deity cannot provide good explanatory grounds for any phenomenon. The problem with the “minimal view” is that in trying to be as vague as possible about the nature and motivation of the deity, the hypothesis loses any explanatory force, and so cannot be admitted on scientific grounds. Of course, as the example of quarks and neutrinos shows, scientific accounts change in response to new data and new theory. The default position can be overcome.
Read the full interview here


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