Smolin rebuts Carroll--try to explain the laws of physics Like the Tegmark Math Universe thread the topic here is properly Philosophy of Science with input from physics. If TMU thread gets moved to Philosophy forum then this thread certainly should too. the issue is whether one should try to explain the laws of physics (why they are what we find them to be) Edge had this discussion starting from a NYT Op-Ed by Paul Davies that I didn't think was very interesting. The interesting part came out in the COMMENTS that Edge elicited. Here are the comments. http://www.edge.org/discourse/science_faith.html They are by 9 people Jerry Coyne, Nathan Myhrvold, Lawrence Krauss, Scott Atran, Sean Carroll, Jeremy Bernstein, PZ Myers, Lee Smolin, John Horgan Here is the original Davies op-ed piece "Taking Science on Faith" in case anyone is curious: http://www.edge.org/3rd_culture/davies07/davies07_index.html What I liked is that Carroll said we should not try to explain the laws of physics, and Smolin contradicted him in an interesting way. I'll get some quotes. Here's a sample of what Carroll said ==quote== The final possibility, which seems to be the right one, is: that's just how things are. There is a chain of explanations concerning things that happen in the universe, which ultimately reaches to the fundamental laws of nature and stops. This is a simple hypothesis that fits all the data; until it stops being consistent with what we know about the universe, the burden of proof is on any alternative idea for why the laws take the form they do. But there is a deep-seated human urge to think otherwise. We want to believe that the universe has a purpose, just as we want to believe that our next lottery ticket will hit. Ever since ancient philosophers contemplated the cosmos, humans have sought teleological explanations for the apparently random activities all around them. There is a strong temptation to approach the universe with a demand that it make sense of itself and of our lives, rather than simply accepting it for what it is. Part of the job of being a good scientist is to overcome that temptation. "The idea that the laws exist reasonlessly is deeply anti-rational" is a deeply anti-rational statement. The laws exist however they exist, and it's our job to figure that out, not to insist ahead of time that nature's innermost workings conform to our predilections, or provide us with succor in the face of an unfeeling cosmos. Paul Davies argues that "the laws should have an explanation from within the universe," but admits that "the specifics of that explanation are a matter for future research." This is reminiscent of Wolfgang Pauli's postcard to George Gamow, featuring an empty rectangle: "This is to show I can paint like Titian. Only technical details are missing." The reason why it's hard to find an explanation for the laws of physics within the universe is that the concept makes no sense... ==endquote== I think some readers can probably see this contains a number of erroneous statements protected by a little strawman rhetoric. Science has barriers and they sometimes shift. The chain of explanation never really terminates. It's always legitimate to push further. Whatever laws we have, that have been well-tested and found reliable, it is always fair to say "these laws should have an explanation from within the universe," and to look for it. In fact this quest has succeeded in the past. Smolin gives an example of where an explanation was found for a law of nature, and we can think of others. It's NORMAL to look for and to find deeper explanations of already established pattern. Mathematics is a human language, one that could have evolved differently. Surely it is a rather good language, but its specifics are largely accidents of human history. The human brain is admirable in its ability to understand and explain, but it too is an accident of evolution. Mathematical laws empirical models and explanations are human artifacts: when we find a deeper explanation for an established law we are only improving on our own work. The odd thing was that Smolin was the only one of the 9 commentors who made this point! He didn't say what I just said, it was somewhat different. I'll get a quote. BTW I think the thing is red is flawed. The opposite statement also fits the data equally well (that the chain of explanation continues indefinitely). And this agrees with our everyday experience of explanations. Also the red statement involves something that is not well-defined, like referring to "The King of France". What does "the fundamental laws of nature" mean? Have you ever seen one? It would necessarily be a human artifact expressed in some human language, this is what laws are, probably some form of mathematics developed in some future century---but can you really treat that as a clear idea suitable for a logical statement about the termination of a sequence?