Fine tuning argument

September 26, 2009

PostScript: This has turned into a massive post, I do apologize. It’s also kind of dry and not particularly funny. Maybe I’ll see if I can liven it up with pictures or something to make it less daunting.

I believe I wrote a piece on this topic a while ago after some goon gave a talk at an Edinburgh Creation Group meeting but this will be a more structured approach rather than a rant, I hope. The fine tuning argument is something that I’ve seen come up a few times in online discussions and it’s pretty stupid. Not quite up there with the ontological argument which I may write up about soon, but pretty stupid when you come to think about it.

The fine tuning argument simply states that there are a number of cosmological constraints which must be within a certain threshold in order for life to exist, and since they are within those thresholds that allow life to exist, it’s reasonable to conclude that the universe was designed that way with life as it’s purpose. It often comes side by side with arguments about the earth being perfect for human life which I’ll also mention here very briefly, and the strong anthropic principle which is quite similar, but also goes further to say that a universe must have the properties necessary for life, otherwise it wouldn’t exist.

So lets start with the whole Earth being designed for us thing. The argument usually goes along the lines that if the Earth was any further away from the sun it’d be too cold for life, and any further away, it’d be too cold. If the moon was any closer then the tides would cause massive flooding which would make land based life impossible, any further away and the tides wouldn’t be enough which means a lot of water based life forms wouldn’t be able to survive, things like that.

Well I have two arguments agains this. First of all is that life has evolved on this planet to adapt to its environment. Yes we couldn’t survive if it was too cold, but if it was a little more cold other life forms could have arisen. We do have some beings on this planet living in very difficult conditions. Similarly if the tides were different, we would have evolved differently, just as if gravity was greater on this planet we’d have evolved a lot differently. The second argument is that we shouldn’t be surprised that we are able to live on this planet, since this is where we live and those conditions are necessary in order for the development of an intelligent observer. If this planet wasn’t capable of supporting life, then we wouldn’t be here, just as if another planet that now isn’t capable of supporting life was, then life may have evolved there and they’d be saying the exact same thing. It’s no coincidence that life has developed in conditions suitable for life. As Douglas Adams was known to say, a puddle wakes up one morning and thinks: ‘This is a very interesting world I find myself in. It fits me very neatly. In fact it fits me so neatly… I mean really precise isn’t it?… It must have been made to have me in it.'” This is the weak anthropic principle. If there are more planets capable of supporting life than the inverse probability of life developing on any one of them, then actually life developing somewhere in the universe would be a statistical certainty rather than something to be surprised about.

Then we get to the fine tuning argument itself which is that not only is the planet designed to support us, but the universe too. So if the strong nuclear force was a bit different then heavier elements would be impossible to make, meaning life wouldn’t have formed, and if the Big Bang had expanded any slower it would have collapsed leaving not enough time for life to develop.

There are a great many arguments against this. First of all, to notice that the VAST majority of the universe does not support life, and then to claim that the purpose of the universe is to support life, is massively arrogant. Clearly the universe is better suited to making black holes than it is to supporting life, since we have observed many black holes and are yet to observe a planet with life other than ours (ok, black holes are also easier to observe but you get my point). The supporters of this argument are arbitrarily deciding that life is the purpose of the galaxy, even though it does other things much better. There is no reason to suppose that any natural phenomenon requires a fine tuner any more than any other, other than subjective judgement. In fact human beings have created areas far more finely tuned to supporting life than even just the planet Earth, never mind the rest of the universe. If we can do better than this creator, well then I’ve got better things to do than waste my time worshipping this lousy intern with a bad attitude.

Secondly, many of the constants are related so although Hugh Ross says he has 101, it’s actually much fewer than that. For example the force of gravity and the rate of expansion of the universe are related, and cannot be changed independently. This reduces the odds considerably.

Thirdly, we can also apply the weak anthropic principle to this argument. It’s entirely plausible that there could be a multiverse out there with a universe for each one of the possible combinations of the cosmological constants. Many of them may have ended by now since their particular combination rendered a universe un-maintainable. Many of them may not have even started. In this case, just as it’s no surprise that we’re on a planet that supports life, we should not be surprised that we’re in a universe that is capable of supporting life, since we are, you know, alive.

At this point the religionist will point out that since there is no evidence of a multiverse, then it is faith just the same as believing in a creator. My response to that is that it is a small leap of faith, but nothing like to the extent that belief in a creator is, since we live in one universe and see no reason why something similar could not exist outside of it, whereas we have no experience of anything like a being capable of creating a universe.

On a similar vein, it could also be that the cosmological constants are different in different parts of the universe. We have only observed a very small part of the universe and although I’m not so big on physics that I know it’s possible, it’s not beyond question. If we live in an oscillating universe, every time there’s a big crunch it could be that the cosmological constraints are scrambled. The idea of a fine-tuner is one that I don’t really accept because it implies that there’s some kind of machine with knobs that are turned by someone, which assumes the conclusion and begs the question, but let’s say that the universal constants can be changed and are, at random. Maybe in the vast majority of cases a universe isn’t possible, so the constants keep scrambling until a Big Bang happens. Maybe only a fraction of those universes are capable of supporting life, but again with the weak anthropic principle we should not be surprised that we live in one that does.

Just as a bit of an addition to this point, it could be that the constraints of our universe are conducive to the development of many different forms of life. This would kind of piss on the fire of a religionist who considers humanity to be the sole point of the universe. It could also be that a fairly wide range of universal constants different to the ones we enjoy in this universe may be conducive to the development of some kind of life. This reduces the magical properties of the universal constants we have and reduces the odds of life developing considerably.

Additionally, we don’t know how the universe works and we have no idea how many different combinations of the universal constants are possible! Without such knowledge, claiming that the constants have been fine-tuned is nothing more than speculation.

Now I’m going to get a little more philosophical and try to argue that the argument is actually self-refuting, partly inspired by the “Why God almost certainly does not exist” chapter of Dawkin’s God Delusion (which in that context I actually don’t think is a particularly good argument, but whatever). The argument claims that in order for life to exist there must have been a creator who fine tuned the constants. And yet in the same breath it assumes the existence of a creator who existed in conditions that did not require a creator. So either the initial premise that these conditions require a creator are false, or we have an infinite regress of creators fine-tuning the universe to make the existence of the next creator possible.

Additionally, it could be that the probability of the constants being the way they are is lower than the probability of the existence of a supernatural creator. That would make our existence unlikely, but a naturalistic explanation more likely than that of a creator, which means it was just a lucky roll of the dice.

The final part of this set of arguments (and I promise this’ll be short) is that the universe must contain life, else it would not exist. Well, that’s just a lie. The universe would still exist if there was no life in it, it would just go unobserved.

So I think I’ve made a pretty strong case. Sorry about that.


Back to the ECG… again!

October 15, 2008

So last night kick-started another series of lectures from the Edinburgh Creation Group, hosted at the Greyfriars and Buccleugh Free Church. Take note that I’ve added their blog to my blogroll on the right of your screen. I only discovered it yesterday but it’s good to have a written explanation of a theory. I’ve often said that text such as on websites and forums is a much better medium through which to hold a debate than in person, so maybe it’ll be a catalyst for further blog posts in the future.

Anyway last night’s presentation was entitled “Chosen Planet: Earth’s Uniqueness for Life” by Dr George Marshall. In many ways it was quite similar to another talk last year but it didn’t go anywhere near as far as that one did. Several things were covered that I wasn’t aware of. For example, I knew that the moon caused the tide but I thought it was just the gravitational pull of the moon which pulled the water towards it, causing deeper water. Apparently there is also a high tide on the opposite side of the earth too! The point was that if the moon was closer it would cause catastrophic floods which would hinder the development of life on earth. Any further away, and the oceans wouldn’t be churned up enough to allow nutrients to come to the surface and feed the algae which are so fundamental to the balance of oxygen and carbon dioxide in the atmosphere. But ours is juuust right, so that’s ok (you’ll notice this becomes something of a theme).

Next up is the Earth’s orbit. If it were smaller, we’d be too hot, bigger and we’d be too cold. If our orbit were more elliptical the temperature would be too temperamental, and if other planets had elliptical orbits it would pull ours out of orbit creating the same problem. A bigger orbit would also result in a greater level of vulnerability from comets and asteroids. But ours is just right.

Many stars, including red dwarves, give out massive solar flares which would also make the climate too temperamental to support life. But ours is just right. Our solar system’s location in the galaxy is also idea to support life.

So, as the more astute among you may have noticed, this is no coincidence. We shouldn’t be surprised that, as living beings, we live on a planet that is suitable of supporting life. I was about to point out that the way the world is is exactly as we should expect it if it happened naturally, when someone on the front row came out with “What exactly is your point?” What followed was a very heated discussion whereby the question-asker didn’t at all make himself clear, really annoyed Dr Marshall (who didn’t understand the point he was making at all), and abiogenesis was brought up which has absolutely nothing to do with the topic at hand (oh, I should mention that halfway through the presentation it emerged that Dr Marshall is a biologist, not an astronomer), and the discussion went nowhere. I kind of brought it back up again in a more polite and clear way, and got the answer we were looking for. Dr Marshall wasn’t arguing that all these parameters amount to such a coincidence that God must have done it, it’s just that you have to step back and say “wow”. He still referred to it as a coincidence though, so I don’t think he grasped the idea that it’s not a coincidence at all.

Anyway, I think this shows the importance of at least appearing to be tolerant of people’s ideas. You don’t get anywhere by shouting and screaming, you just kind of come across as a bit childish. We were both on the same page, he just went about it a different way which I think was detrimental to the discussion.

In short, I’d heard all the arguments before and more along the same vein (which if people would like to bring up here I’m happy to discuss – last time Dr Ross’ 101 quantities was mentioned), so it was nothing new, although some things were mentioned that I hadn’t been aware of. It was also claimed that it takes faith to believe in a multiverse or an oscillating universe just as it does to believe in God. I have my own opinion on that and if anyone wants to discuss it further, drop me a comment here.