- Considering perfect order of the universe, there must have been extremely sensitive values in motion, during the expansion of the Big Bang. Can you tell us about the order that began with the Big Bang, such as the cosmological constant and others and how precise these values are?
- The fine-tuning problems, some people call them problems, fine-tuning issues of the universe are really well known and widely discussed in the physics community. I would say one of the things that is very compelling to me is an argument made, I’m going to steal a lot from a philosopher named Robin Collins, who is also from Pennsylvania. At a meeting a couple of years ago, he gave a very nice talk. One of the problems of the fine-tuning is not just that there are a lot of improbable numbers that have to be exactly so, or we couldn't live. Because in many versions of understanding fine-tuning, people will say, "well, it’s not really a problem at all because you could just have a lot of universes, a lot of tries, then eventually just by random chance, you would get the things that you need".And so the analogy would be: suppose that you have a target for an arrow. And you randomly shoot arrows everywhere. And if you have enough tries, eventually you will get one that hits the target. And so then, you add to this and you say: now we find that there is just not one fine-tuning but there are multiple fine-tuning parameters. There is the ratio of gravity and electrical force, the expansion rate of the universe, the speed of light, all of these things have to be pretty much exactly what they are or life couldn't exist. And some people would say,"Well, that’s not really a problem, because again if you have all of these different chances, all of these different universes, eventually you will be able to hit all these different targets". But in that kind of thinking, you are sort of thinking that you have one target and you shoot the arrows in a bunch of different ways and you hit one target and then you go on to the next target and you do the same thing until you get all these answers. The problem is with the fine-tuning parameters that we know of, they all have to be true simultaneously. You can't just have one be true and the other ones not be true; you have to have all of them true at the same time. And laws of physics don't allow you; if you change one, you often times will change some of the other parameters as well. So the analogy that Robin Collins was discussing was imagining that you have a whole bunch of hoops, of circles, and maybe a hundred of them, and you have to shoot an arrow and satisfy all one hundred of these hoops by shooting an arrow through. Now if the hoops are all in different places, there is no arrow that will ever go through all one hundred, because you shoot this one and miss that one. The only way to do is to have all one hundred hoops lined up in a straight line so that you can satisfy all of the constraints simultaneously. Then you have to ask ‘what are the odds of having all of the hoops in line?’. Even if I had lots of universes and I am shooting arrows in all different directions, if the hoops are not all lined up, no arrow will ever satisfy all of the hundred hoops at the same time. So you can now say even in the universe, where you have multiple attempts, if the hoops are not lined up, you can't get something that satisfies all the conditions at the same time. So we have a question, a larger question, which is how is it even possible that there is any type of universe that could allow life? Because all of these conditions have to be satisfied at the same time, if one of them is wrong, then none of it works.
