Posted on 01/18/2021 6:25:13 AM PST by Heartlander
We exist, and we are living creatures. It follows that the universe we live in must be compatible with the existence of life. However, as scientists have studied the fundamental principles that govern our universe, they have discovered that the odds of a universe like ours being compatible with life are astronomically low. We can model what the universe would have looked like if its constants—the strength of gravity, the mass of an electron, the cosmological constant—had been slightly different. What has become clear is that, across a huge range of these constants, they had to have pretty much exactly the values they had in order for life to be possible. The physicist Lee Smolin has calculated that the odds of life-compatible numbers coming up by chance is 1 in 10229.
Physicists refer to this discovery as the “fine-tuning” of physics for life. What should we make of it? Some take this to be evidence of nothing other than our good fortune. But many prominent scientists—Martin Rees, Alan Guth, Max Tegmark—have taken it to be evidence that we live in a multiverse: that our universe is just one of a huge, perhaps infinite, ensemble of worlds. The hope is that this allows us to give a “monkeys on typewriters” explanation of the fine-tuning. If you have enough monkeys randomly jabbing away on typewriters, it becomes not so improbable that one will happen to write a bit of English. By analogy, if there are enough universes, with enough variation in the numbers in their physics, then it becomes statistically likely that one will happen to have the right numbers for life.
This explanation makes intuitive sense. However, experts in the mathematics of probability have identified the inference from the fine-tuning to the multiverse as an instance of fallacious reasoning. Specifically, multiverse theorists commit the inverse gambler’s fallacy, which is a slight twist on the regular gambler’s fallacy. In the regular gambler’s fallacy, the gambler has been at the casino all night and has had a terrible run of bad luck. She thinks to herself, “My next roll of the dice is bound to be a good one, as it’s unlikely I’d roll badly all night!” This is a fallacy, because for any particular roll, the odds of, say, getting a double six are the same: 1/36. How many times the gambler has rolled that night has no bearing on whether the next roll will be a double six.
In the inverse gambler’s fallacy, a visitor walks into a casino and the first thing she sees is someone rolling a double six. She thinks “Wow, that person must’ve been playing for a long time, as it’s unlikely they’d have such good luck just from one roll.” This is fallacious for the same reason. The casino- visitor has only observed one roll of the dice, and the odds of that one roll coming good is the same as any other roll: 1/36. How long the player has been rolling prior to this moment has no bearing on the odds of the one roll the visitor observed being a double six.
Philosopher Ian Hacking was the first to connect the inverse gambler’s fallacy to arguments for the multiverse, focusing on physicist John Wheeler’s oscillating universe theory, which held that our universe is the latest of a long temporal sequence of universes. Just as the casino-visitor says “Wow, that person must’ve been playing for a long time, as it’s unlikely they’d have such good luck just from one roll,” so the multiverse theorist says “Wow, there must be many other universes before this one, as it’s unlikely the right numbers would have come up if there’d only been one.”
Other theorists later realized that the charge applies quite generally to every attempt to derive a multiverse from fine-tuning. Consider the following analogy. You wake up with amnesia, with no clue as to how you got where you are. In front of you is a monkey bashing away on a typewriter, writing perfect English. This clearly requires explanation. You might think: “Maybe I’m dreaming … maybe this is a trained monkey … maybe it’s a robot.” What you would not think is “There must be lots of other monkeys around here, mostly writing nonsense.” You wouldn’t think this because what needs explaining is why this monkey—the only one you’ve actually observed—is writing English, and postulating other monkeys doesn’t explain what this monkey is doing.
Some have objected that this argument against the inference from fine-tuning to a multiverse ignores the selection effect that exist in cases of fine-tuning, namely that fact that we could not possibly have observed a universe that wasn’t fine-tuned. If the universe wasn’t fine-tuned, then life would be impossible, and so nobody would be around to observe anything. It is of course true that this selection effect exists, but it makes no difference to whether or not the fallacy is committed. We can see this by just adding an artificial selection effect to the monkey and typewriter analogy of the last paragraph. Consider the following story:
You wake up to find yourself in a room sat opposite the Joker (from Batman) and a monkey called Joey on a typewriter. The Joker tells you that while you were unconscious, he decided to play a little game. He gave Joey one hour to bash on the typewriter, committing to release you if Joey wrote some English or to kill you before you regained consciousness if he didn’t. Fortunately, Joey has typed “I love how yellow bananas are,” and hence you are to be released.
In the above story, you could not possibly have observed Joey typing anything other than English—the Joker would have killed you before you had a chance—just as we could never have observed a non-fine-tuned universe. And yet the inference to many monkeys is still unwarranted. Given how unlikely it is that an ordinary monkey would come up with “I love how yellow bananas are” just by randomly bashing away, you might suspect some kind of trick. What you would not conclude, however, is that there must be many other monkeys typing rubbish. Again, what you need explaining is why Joey is typing English, and the postulation of other monkeys doesn’t explain this. By analogy, what we need explaining is why the only universe we’ve ever observed is fine-tuned, and the postulation of other universes doesn’t account for this.
But isn’t there scientific evidence for a multiverse? Some physicists do indeed think there is a tentative empirical evidence for a kind of multiverse, that described by the hypothesis of eternal inflation. According to eternal inflation, there is a vast, exponentially expanding mega space in which certain regions slow down to form “bubble universes,” our universe being one such bubble universe. However, there is no empirical ground for thinking that the constants of physics—the strength of gravity, the mass of electrons, etc.—are different in these different bubble universes. And without such variation, the fine-tuning problem is even worse: we now have a huge number of monkeys all of whom are typing English.
At this point, many bring in string theory. String theory offers a way to make sense of the possibility that the different bubbles might have different constants. On string theory, the supposedly “fixed” numbers of physics are determined by the phase of space, and there are 10500 different possible phases of space in the so-called “string landscape.” It could be that random processes ensure that a wide variety of possibilities from the string landscape are realized in the different bubble universes. Again, however, there is no empirical reason for thinking that this possibility is actual.
The reason some scientists take seriously the possibility of a multiverse in which the constants vary in different universes is that it seems to explain the fine-tuning. But on closer examination, the inference from fine-tuning to the multiverse proves to be instance of flawed reasoning. So, what should we make of the fine-tuning? Perhaps there is some other way of explaining it. Or perhaps we just got lucky.
in a hundred million years, it won’t matter.
There will be no remanants of anything left behind that give a clue as to what human did to human on this sprint to eternity that has hit the cosmic brick wall and becomes just another ripple in the continuum.
>So “life” is an entity that exists without a universe? And all the preexistent “life” does is adopt, adapt and fluorish in its physical milieu?
Life is dependent on the universe. All life must adapt to flourish.
>Ah, but it doesn’t appear inevitable (or even enviable ;-) ) at all from a scientific viewpoint
I Hate spellchecker.
“Any event, regardless how improbable, once it has occurred becomes inevitable.” — Captain Compassion
This is the argument that the universe is created and not just the result of pure chance.
P(X|Y) = P(X)[P(Y)+(1-P(Y))P(X)]?
It’s just so much easier to understand than
P(X|Y) = ....P(Y|X)P(X)/P(X)
Thinking in terms of relating Y given X to solve X given Y makes my brain hurt.
I once calculated the likely number of planets with intelligent life using the Drake equation (which I accidentally called the Ernst equation in a previous post). I came up with two.
It’s not meaningful — I dramatically underestimated the number of planets in the universe — but I figure getting a number so close to one was like flipping a bat and landing it straight on its head... and then trying to knock it down with a second bat, and having it balance on the other bat.
“Since it has indeed happened on earth...”
Life exists on Earth. That much is established. What is not established is that life on Earth arose spontaneously from natural processes. You’ve got to actually establish that fact if it is a fundamental building block of the rest of your argument about the existence of life in the universe.
Cannot argue with deus ex machina.
Nobody asked you to do that. All you need to do is establish that life just arising spontaneously can actually happen. So far, nobody else has actually been able to demonstrate that.
If you can’t, then the probability range is 0 <= x <= 1, instead of 0 < x <= 1, which is a significant difference when evaluating a probability multiplied by a very large number.
Sure you did. The fact is that life came to exist on earth. Either it was Deus ex machina or somehow inert matter after absorbing energy of various sorts, was transformed into other molecules that came together as organic matter that organized into reproducible entities known as life. Now you can make an argument for deus ex machina if you don’t accept what some call the mystical fairy tale for physicists or the big bang theory. In the end 0x0 is always 0 so just what was at the core of the big bang and how did it get there? There is much mysticism at the center of physics.
“Either it was Deus ex machina or somehow inert matter after absorbing energy of various sorts, was transformed into other molecules that came together as organic matter that organized into reproducible entities known as life.”
We still have not established that it is possible for organic matter to self-organize into life. Just because you can break something down into two possibilities and reason that one must be true, doesn’t mean that you have established that either of those is actually possible or likely to have happened. You can’t just skip a step because you can’t manage to complete it. If you tried that with a mathematical proof and turned it in to your professor, you’d get an “F”, even if you somehow arrived at the correct answer.
The actual correct analysis of the probability of life existing on other planets is that the answer is currently an unknown quantity, since we can’t establish this baseline probability at all, and therefore we cannot evaluate any further equations that would require us to know or at least be able estimate that probability. Any other answer is based on flawed logic at this point.
“It’s also oxymoronic in the sense that the universe is everything that exists, which means that “multiverses” are part of our universe.”
Well, you can define the universe as everything that exists, which by definition rules out any multiverse. Or you can define the universe as everything that it is possible for use to observe. In that case, we can never observe any evidence for the multiverse so it’s a scientific dead end.
I think the dark matter/dark energy are just cosmic “fudge factors” to plug deficiencies in the current theories, but the multiverse stuff is just philosophy being done by people who are unqualified to do philosophy, because they’ve hit a brick wall that science can never penetrate. Really they should be leaving the philosophy to philosophers, but many people seem to have adopted the notion that science is the only legitimate means to reliable knowledge, so they do not want to admit that there are questions science can never answer, and have resorted to this pseudophilosophy in an attempt to pretend that science can answer such questions.
Not really.
Unless you really want to NOT value life.
And then it appeals because fits into your moral template rather then having anything to do with reality.
The reality is that go large or go small most of what is around us is empty space.
Matter is rare, living matter even rarer and intelligent living matter the rarest of all.
It should be cherished not tossed away like garbage.
And one day in the not too distant future, you'll see that it is MUCH WORSE than any of the so called genius experts would imagine
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