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Anthropic Principle Interpretations

  1. May 24, 2010 #1
    Ok so I am writing a physics "research" paper over any topic we like. The one requirement is that the intro must be about the Anthropic Principle. I have searched it all over the internet and have found it hard to understand what the heck it is talking about. (I am not into this kind of thing because it has to do with what you believe more, so I ask anyone's opinion.)

    The following is what I think it was saying,

    Weak Anthropic Principle:
    "Of course we see the constants of physics as 'fine tuned' because we would not be able to see them any other way, since we exist. Say the constants differ in different regions of the universe, or that there are even multiple universes with different constants. We, existing, must be in a region or universe with the constants that allow life to form."
    In other words, there is nothing special about the constants as they are.

    Strong Anthropic Principle:
    The universe's sole purpose was to create life, and to thereby be observed. The constants were such from the very beginning as to permit the formation of life sometime. The constants are very special, in that if they were changed even the slightest bit, life would not be able to form.

    In my opinioin, the WAP seems more atheistic and the SAP seems to favor creationism.

    Is that what those Principles mean, or have I understood it incorrectly?
    Thanks, any help would be great.
  2. jcsd
  3. May 24, 2010 #2
    What class is this for if I might ask?
  4. May 24, 2010 #3
  5. May 24, 2010 #4
    I think you have basically got it.

    But I personally would add that both seem a little too "human oriented". As a person trained as a biochemist that happens to really like physics I would say even the weak principle is a bit too much. This principle also seems to imply that the universe necessarily leads to some life form to observe its principles, study them, describe them and wonder about them. Modern humans (100,000 years) and our close ancestors (3 or 4 million years old) did not spend this much time evolving to determine that gravity is much weaker than the electric force and then wondering about it. I think finding food in grassy plain areas with nearby forests and mating were probably much more important in forming our brain.

    I see no reason why life, if it does exist elsewhere, must necessarily lead to organisms who wonder about themselves and the cosmos.

    If you pick out one rock out of a number of stream beds with billions of rocks you can then claim that it was a miracle that you picked up that particular rock. Bacteria were around for 2 billion years before more complex eukaryotic cells evolved from them, why the heck did it take so long... And then good gosh, going from a euk. cell to something that wonders about its place in its surroundings... a bit too much.

    Maybe some fodder to refute or use in some way for your paper. I think you have basically go the ideas though based on what I have read and discussed with others.
    Last edited: May 24, 2010
  6. May 24, 2010 #5
    I'm glad to hear I didn't misinterpret it.

    Yeah, it is interesting stuff.
  7. May 25, 2010 #6
    You should read this:

    http://knol.google.com/k/the-anthropic-principle# [Broken]

    Because the AP is actually an ideological statement about physicists.

    The "variant interpretations" are derived from the physics that brought the AP into focus as either, a cosmological principle, (strong) or a selection effect, (weak), but Brandon Carter's formalization basically stated that physicists practice a religion, or an "anti-religion" that could be called "Copernicanism", which is the unjustified belief in a Copernican-like cosmology, that arises from the mediocrity principle and the principle of relativity.

    A true Anthropic Cosmological Principle might be something as simple as an energy conservation law that requires carbon based life to arise and evolve over a specific "Goldilocks" region, or layer of the observed universe, and at an equally specific "Goldilocks" time in its history.

    The physics applies to all carbon based life unless intelligence is a necessary function of the thermodynamic process that requires it. For example, something like this:


    But beware of dogma, because absolutely nothing has changed about the way that physicists and, um... bio-chemists... ;)... assume without justification that they know that life isn't relevant to the process on some "special" level.

    Praise be to Copernicus... and all that unscientific holy roller crap that you will get from virtually every last liberal scientist that you will ever meet.
    Last edited by a moderator: May 4, 2017
  8. May 25, 2010 #7
    From the article above...

    Order seems to be the name of the biological game, and evolution leads to more complex organisms and more organized structures.

    This is just not necessarily the case. There are plenty of populations that become less complex thus more generalists in their lifestyle. In fact many of the first things to go with a change in environment, especially if drastic, are the more complex organisms that cannot handle the extremes. This is a clear trend we see in the history of life on earth.

    There is no good reason to suggest that life must lead to organisms that ponder the way the universe works. It may be true that life automatically means evolution to organisms that are self aware and curious about the rules that govern their surroundings, but there is nothing I personally have seen or read to suggest that this is true so I doubt it. This does not mean that I am dead wrong. I just dont see any evidence to personally convince me otherwise.
  9. May 26, 2010 #8


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    If I may add something. The AP comes basically down to the statement that a conscious observer pondering about the laws of nature / history (initial conditions?) of nature will find laws of nature that allow a conscious observer pondering about them to exist. Trivial - tautological - as it may seem, it is far from evident, because you can think of many laws and "initial conditions" that simply don't.

    We are on a remarkable planet that allows for life, simply because otherwise we wouldn't be here to wonder about it.

    The AP gets another twist when the universe becomes "very big", as in "multiverse", because then we can use it as "conditional probabilities". This flies in the face of certain deductions such as Drake's formula that tries to estimate the number of civilisations in our galaxy or something. One has, in such a case, indeed to admit that all observations in our "observable universe" are biased by this condition, that we exist. In a "very big" universe, very unprobable events will nevertheless happen, but normally they should happen "far away". The fact of existing, as a living conscious being, means that those (even rare) patches of universe where living conscious beings exist, are now priviledged (biased to be "close"). Being alive and conscious is an "improbability drive" as in the Hitchhiker's Guide.

    Imagine for instance that the actual unbiased probability of develloping life like it did on earth, is, say, 10^-80. That is, there shouldn't be any life in the observable universe. Well, there is. No contradiction, because we are here and the chunk of universe we observe must necessarily contain us. The conditional probability to find ourselves in our chunk of universe is 1.
  10. May 26, 2010 #9
    Which is why I said "like" this. The point of the AP is that scientists don't generally even look in this direction because they are already pre-disposed to a Copernican conclusion, but this is the book that Sagan and Schneider wrote in case you are interested in further reading:

    http://www.press.uchicago.edu/presssite/metadata.epl?mode=synopsis&bookkey=3533936 [Broken]

    Part of the problem that these guys have is that the originator of the theory died unexpected and before Carl Sagan's son ever came along, so it is quite possible that some important ideas got lost in the translation.

    Personally, I think that it's pretty interesting that humans are one of only three sources that can isolate enough energy to directly affect the symmetry of the universe by creating matter/antimatter pairs, along with Black Holes and Supernovae.
    Last edited by a moderator: May 4, 2017
  11. May 26, 2010 #10
    How long is it to be?

    I may suggest this outline:

    • Introduction
    • Who said it? What was originally meant
    • Variations, with different degrees of meaningfulness to physics
    • Fine Tuning the constants of nature
    • Tautology -- it's a cop-out
    • Multiverse or other statistical explanations
    • It's not as strong as you think -- different physics might also produce life
  12. May 26, 2010 #11
    It is very interesting.

    I have no problem with anything written in the little promo. Seems perfectly reasonable and if fact delightfully logical. What I have a real question about is the idea that life should lead to something that wonders about itself and the world about. I see this as a very quirky sideshow. A reading of Steven J. Gould's last chapter in his book on the Burgess Shale would be closer to how I see things once life takes hold. I think its best to go to the people who actually have studied evolution of life on Earth when asking the question of what happens when life appears and rerunning scenarios of evolution. They most likely have a better grip on it. I dont think astrophysicists and cosmologists have the same view about the evolution of life, and what happens once it is hypothetically established, as evolutionary biologists might based on my reading.
    Last edited by a moderator: May 4, 2017
  13. May 26, 2010 #12
    pgardn, I agree with you about the amount of weight that gets put on the observer as the main functional feature of the AP, and an entropic life principle certainly doesn't place this kind of emphasis on it, but even Carter said that the AP wasn't a complete idea, so everything that's been discovered about the physics since that time should automatically be considered into any variant formulation.

    But I think that there is a combination of biology and cosmology that has to be considered when talking about the evolution of life after it established, because the evolving environmental balance points that the "goldilocks" physics produces are a constant guiding factor in the evolutionary process.

    There are a few biologists and physicists that delve into this from that perspective, Margulis and Lovelock, for example, have touched on the evolving homeostatic balance points that carbon based life appears to have in common with values of the forces and the structure mechanism of the "flat" near-balanced universe itself.

    This commonality most strongly implicates a connection between our existence and the missing cosmological principle, like a solution that's begging a question that very few scientists want to ask, thanks to anything but science.
    Last edited: May 26, 2010
  14. May 26, 2010 #13
    Do you have a link to what Margulis has said regarding this stuff? I would regard her more as a cell/biochemical evolutionary biologist, not a big scale trend type, but she usually has some really good thoughts and imo she writes well and on a level anyone can understand. I think that some of the people that do work in this area or think about this stuff are quite good but cannot always get their thoughts across well. And there are also people, Dawkins for example, who are excellent writers but look to stun people rather than inform. All of course my opinion.
  15. May 27, 2010 #14
    Yes, Lynn Margulis input was the critical differentiation between homeostasis and homeorhesis, which she wrote about in the following book:

    Symbiotic Planet: A New Look At Evolution. Houston: Basic Book 1999

    But you can read some stuff about it all here too:

    Lynn Margulis, a microbiologist who collaborated with Lovelock in supporting the Gaia hypothesis, argued that “Darwin's grand vision was not wrong, only incomplete. In accentuating the direct competition between individuals for resources as the primary selection mechanism, Darwin (and especially his followers) created the impression that the environment was simply a static arena.” In 1999, she wrote that the composition of the Earth's atmosphere, hydrosphere, and lithosphere are regulated around "set points" as in homeostasis, but those set points change with time.
  16. May 28, 2010 #15
    Lovelock's initial ideas I believe taken at face value where very deterministic. So I did kinda crossed him off my list of people to read. I appreciate your effort on the link for Margulis.
  17. May 28, 2010 #16
    Exactly. I often find such things quite anthropocentric. Even to me they seem overly 'life centric'. Who's to say that life is either the most complex or most interesting phenomenon in the universe? There could be other things out there just as strange, complex, and downright cool as life, and probably some even more so. It seems kind of presumptuous to me to say that the universe can only have one emergent property (life) on that order of complexity and intricacy.

    Imagine we go out there and find such things. It's not aliens we'd be most interested in, it would be these things. They would be totally inscrutible and mysterious. Very difficult to probe or understand, because it would operate on the principles of very high level emergent properties. But whatever we learned from them would be substantial; maybe even enough to crack the problem of emergence itself, having an equal or superior example of emergent properties.
  18. May 28, 2010 #17
    Well, I personally would not cross him off of my list for that reason until we have a final theory, and if they don't find the higgs boson or other more speculative "new physics", then that theory may very well look a LOT more deterministic than people currently assume without said justification.

    This is my LongBet:


    You're welcome, and again... something "like" Lovelock and Margulis theory... ;)
    Last edited: May 28, 2010
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