Question from Alex:
Hi, this question has the intention to find if there are direct counter-examples of the fine-tuning argument, by this I mean constants that could be adjustable without impeding the emergence of life in the universe; are there such constants?
If the universe was designed by an intelligent creator, we should expect things like the fine-tunings for life we observe, but what if we find there are examples of non-fine tuning? Or have we finally found the evidence for a creator?
Thanks.
Answer by SmartLX:
In Just Six Numbers by Martin Rees, he brings up one direct counter-example: the value of the gravitational constant could vary by up to a factor of 3,000 before it precluded the formation of stars and thus the emergence of life. Some of the other constants would throw out the balance if they changed by themselves, even slightly, but if other constants were also different it could compensate very well. If you consider only the six most well-known constants, and the idea that any of them could be any value positive or negative, that presents an enormous six-dimensional sample space of possibilities which isn’t even close to being exhausted as a source of other viable “settings”.
Even if there were no counter-examples, and every constant had to be exactly what it is for life to emerge, it wouldn’t be evidence for a creator until all other possibilities were eliminated. Contrary to the sample space I’ve described, maybe the nature of the early universe was that each constant could only have been within a small range. Maybe each constant influences the others, such that the current constants are in stable equilibrium for purely physical reasons. Maybe we’re in the one universe out of billions of billions of universes with varying constants where they all came out just right. There are also counter-arguments like the idea that if the universe were actually fine-tuned, such a mind-bogglingly huge percentage of it wouldn’t be empty and/or uninhabitable – it would likely be friendlier or smaller.
To say that the universe supports life is not to say that the universe is fine-tuned for life, because one can happen without a “tuner” and one can’t. Keep an eye out, because many arguments for God based on this idea try to pull that particular switcheroo.
Tag: martin rees
The Consistent Electron
Question from Andrew:
How do atheists explain the existence of symmetry?
How do you explain for example; that all electrons have the same charge and mass, and that they are all negative if they are the product of blind chance, and purposeless mechanisms?
How do you explain this, if blind chance and purposeless mechanisms don’t know that this is necessary for life to exist?
Answer by SmartLX:
When a hose or a faucet is dripping, why is every droplet the same size? Because in that particular situation, the weight of the water that gathers at the lowest point of the opening overcomes the surface tension holding it on when it reaches a specific volume, and unless you move things around that volume doesn’t change. Similarly, all the nearby droplets in a given rainstorm are about the same size because each one begins to fall when a specific amount of water vapour precipitates at one point inside a cloud. No one is there inspecting all the droplets on a production line before they fall, they just all end up being alike because conditions are constant.
So it is with the universe as a whole. Outside of certain extremely rare conditions, some properties of matter and energy are exactly the same no matter where you are: the gravitational constant, the strong and weak nuclear forces, the number of spatial dimensions and so on. This means that the amount of matter that forms a proton or the amount of energy that forms a discrete electron is the same everywhere. They don’t need an auditor to check that every particle is built to code, because they simply can’t be any other way.
We don’t know why these properties have the numerical values they do, but as it turns out they are hardly “fine-tuned” for life. In his book Just Six Numbers, Martin Rees finds that the force of gravity for example could vary by up to a factor of 3000 before stars couldn’t form, so there’s a wide range of gravitational constants that would still allow the building blocks of life (carbon, oxygen, etc.) to form and gather. I did a piece on this a while ago, so here it is.
We also don’t know why these properties stay constant and homogenous, but we do know that life couldn’t exist for long if they weren’t. So if there are multiple universes where they may or not be constant, we’re in one of the ones where they are. That’s one possible explanation; another is that a universe simply has that property as part of what holds it together. If you prefer the idea that God ensured and continues to ensure that the fundamental constants of the universe don’t budge, then you’re assuming the existence of an eternal, powerful, purposeful entity which has stayed constant for even longer than the universe without outside help, and should by your reasoning be regarded as even more unlikely. Asserting something unexplained or inexplicable to explain something else does not increase understanding, when there is otherwise no clear evidence that the explanatory entity even exists.
Fine-Tuned Gravity: Don’t Touch That Dial
Question from Cedric:
Victor Stenger says supporters of the Fine Tuning argument make the mistake of holding all the parameters constant and varying just one. He says “changes to one parameter can be easily compensated for by changes to another, leaving the ingredients for life in place.”
“The ingredients for life” is a more complex case since it involves several parameters but if one were to examine a simpler case involving only one parameter then the legitimacy of Fine Tuning might be easier to discern.
Take the force of gravity. The Fine Tuning argument says it had to be precisely what it is in order for the universe to expand as it did after the Big Bang. Too strong and the universe would collapse back to a singularity. Too weak and the universe would expand too rapidly. This doesn’t seem to depend on other parameters. So doesn’t the exactness of gravity alone imply design?
Answer by SmartLX:
If you’re going to circumvent Stenger’s argument by focusing on a single value, gravity is the wrong one to pick because it didn’t have to be all that exact. In Martin Rees’ book Just Six Numbers he finds that the gravitational constant would have to increase by a factor of 3000 to preclude the formation of stars. (I’ve never seen anyone use the same approach on another constant, so I suspect none of the others have similarly obvious independent significance.)
Creationists and other apologists have not contradicted Rees; they’ve taken two other approaches to dismissing this inconvenient amount of leeway. Both are found in this article, which is typical of a fair few apologetic articles attacking Rees’ conclusion of a lack of fine tuning. (Their abundance suggests to me that Rees struck a nerve.)
1. If gravity were nearly 3000 times stronger, they say, stars wouldn’t last even a billion years and life wouldn’t have time to form, so the universe is still fine-tuned for the really important thing, life. Well, the fact that this aspect of the extreme case isn’t workable doesn’t negate the fact that gravity could change an awful lot before there was any real difficulty.
2. A factor of 3000, they say, is still tiny when you consider that the different forces in the universe differ by factors of up to 10^40. True, but it’s still 300,000% so it’s huge compared to the actual value, and there’s no evidence to suggest that gravitational forces in a fresh universe are even capable of reaching the levels of our universe’s strong nuclear force. There’s an underlying assumption that each of the constants was selected from the same huge or infinite range of possible numbers, and there’s no basis for that assumption.
Even if gravity had to be what it really is for life to form, to within a zillionth of a percent, it would not simply “imply design”. We don’t know nearly enough about what went into the physical “setting” of the constant to jump to that conclusion. Alternatives include but are not limited to the following:
– A huge or even infinite number of universes exist, each of them with different constants, such that the probability of one of them hitting the magic spot is really quite reasonable. Ridicule the multiverse hypothesis if you like, but evidence has emerged suggesting its likelihood. (Additional universes seem more likely to me than a god because we know there’s at least one universe. If your cabbage patch is destroyed and you find one little rabbit, you don’t imagine that Bigfoot did the rest; you wonder where the other rabbits are hiding.)
– The value of the gravitational constant is a result, not a parameter. When a Big Bang happens, gravity comes out at 6.673 because of how a Big Bang happens, or else the constant is dependent on the other constants. (Pi is a good analogue for this; the value near 3.14 results from the physical properties of a circle.)
– The gravitational constant might have started anywhere, but it varied before it reached a stable equilibrium at its current value. Something about 6.673 stops it from wanting to shift. (This is one possible explanation for cosmic inflation.)
Finally, if you disregard all of the above, we’re ultimately comparing the probability that a universe with incredibly fortunate physical qualities arose naturally to the probability that it was designed by an even more complex, exotic, powerful, hypothetical entity with no origin at all. That might be a contest if the existence of the other entity were assumed, but you can’t take that liberty when the whole point of the discussion is to establish that entity’s existence.