Pharyngula

Posted by: Lynn | February 5, 2007 10:48 AM

This was a fun read.

The whole anthropic principle thing just mystifies me. How can anyone with a functioning brain actually think there's something meaningful in the claim that this universe had to be created just to fit us?

Clearly, life fits our particularly corner of the universe, not the other way around.

Just mystifies me.

Lynn

Posted by: Stephen Frug | February 5, 2007 11:00 AM

That was a damn fine post -- sharp as a tack.

So yeah, I'd quit if I were you. Retire while you can still make it look graceful & voluntary. If she starts in on the squid, what have you got left?

Posted by: quork | February 5, 2007 11:53 AM

The whole anthropic principle thing just mystifies me.

My favorite is the anthropic principle combined with the argument from biological design: The universe is not suited for the natural development of life as wee see it, threfore God did it. On the other hand, if the universe is suitable for the natural development of life as we see it, then it must be because God did it.
Heads I win, tails you lose.

Posted by: Blake Stacey | February 5, 2007 1:41 PM

I wrote a pretty long post over at Lacrimae Rerum, which might be interesting to readers over here. The context arose from a trollish attack upon Skatje's description of "anthropic" reasoning.

I have always appreciated Carl Sagan's take on the subject:

There is something stunningly narrow about how the Anthropic Principle is phrased. Yes, only certain laws and constants of nature are consistent with our kind of life. But essentially the same laws and constants are required to make a rock. So why not talk about a Universe designed so rocks could one day come to be, and strong and weak Lithic Principles? If stones could philosophize, I imagine Lithic Principles would be at the intellectual frontiers.

If we go by what is actually most prevalent in the Universe, it seems that the Cosmos was made for the benefit of dark energy, with matter merely an incidental elaboration.

If an asteroid had not struck the Earth 65 million years ago, our species would not be here to blog today. Yet, the physical laws of nature would be exactly the same: in such an alternate take of cosmic history, we'd only be short one big rock. The fundamental behaviors of quarks and leptons do not in any way imply our existence. Nor, even if we postulate an intelligence responsible for choosing the number and strength of the fundamental forces, can we deduce a connection between such a Watchmaker and human morality (or any other domain addressed by Western religion).

There really is more empty space (or, if you prefer, dark energy) in the Universe than anything else. Not only do we live on a pale blue dot lost against the starry sweep of a humdrum galaxy, confined to an instant of time and the backwater of space, but we're not even made out of the Cosmos's most preponderant stuff. Even if we consider the familiar matter which we know pretty well (thanks to particle accelerators, not introspection and holy books) we find plenty of things which a parsimonious Watchmaker could have done without. For example, in the set of particles known as leptons, there are electrons and their associated neutrinos. A familiar particle and its lightweight partner; not so bad! But then we discover a muon, which is just like an electron but heavier, and which also comes with its partner neutrino. Who ordered that? As we increase the energy of our accelerators, we find a tau lepton, just like the electron and muon but more massive still. It, too, has an associated flavor of neutrino.

Couldn't God have made the whole shebang without muons and taus? And why does each one need its own neutrino — is the subtle problem of neutrino oscillation (the different flavors mixing into one another as the particles flit through space) so important that the Creator couldn't have made one flavor enough?

Just like leptons, quarks also come in three "generations". Ordinary protons and neutrons are made of up and down quarks, but we also have charm, strange, top and bottom. Why the same number of quark generations as lepton generations, and why is that number three? Since the more massive particles seem only glancingly related to our daily lives, couldn't we just as well have either a greater or fewer quantity of them?

I've posed this question to particle physicists, to make sure I'm not missing a point myself, and their reaction has inevitably been to shrug and say, "I dunno." We know with remarkable certainty that in our actual Universe, we have three generations, no more and no less. (Measure the decay rate of the Z boson, for example. The more things it can decay into, the faster it will break down. Knowing the Z decay rate, we can peg the generation count at three.) But couldn't we extend the model "unto the fourth generation" and still have a universe in which heavy elements, complex matter and intelligent life still exist?

Nothing in the physics of today rules out the possibility.

I attended a conference this past summer on collider physics. One of the presentations was about how they figured out the charge of the top quark. According to the plain-vanilla Standard Model, the top quark should have a charge of 2/3 (in units where the electron's charge is -1). However, there was a possibility that the top actually has charge 4/3. Which of those choices is preferable on anthropic grounds — i.e., which choice leads to matter, chemistry and us?

Surprise! Either of them would work. We can't discriminate between options for a fundamental quantity of nature on anthropic grounds. You have to go to the accelerator folks. The latest report from Fermilab's Tevatron, published in Physical Review Letters volume 98, indicates that the data supports a top-quark charge of 2/3 pretty strongly. Chalk up one more for the Standard Model, but keep in mind that anthropic reasoning got us nowhere.

Posted by: Steve Watson | February 5, 2007 2:58 PM

IIRC, I once posted on t.o a calculation showing that the volume of our universe habitable by life as we know it is some vanishingly small fraction -- a respectably large negative exponent -- of the whole. The rest of the place is indifferently lethal.

And this is what they call "fine-tuning"?

Posted by: michael | February 5, 2007 4:40 PM

The island troll should probably be studied. He was classic to a tee. He was honestly just hitting copy and paste from other writing and then adding in insults against those who questioned it. When he was finally stuck in a corner and asked to put up or shut up, he claimed he was being ganged up on and left. It was breath taking in its ability to embody steriotype.

Posted by: Rugosa | February 5, 2007 5:15 PM

I have often said that once you reach 50, you're entitled to use words like "whippersnapper." Skatje is doing you proud.

Posted by: John Marley | February 5, 2007 10:12 PM

I see she's collecting her fair share of nutjobs, too.

Posted by: Torbjörn Larsson | February 5, 2007 11:44 PM

"entropy guides the universe or something like that."

Duh! I meant that IIRC islands ideas are that entropy guides cosmological development in excruciating detail - forcing life to be, and other cranky stuff.