Our Improbable Existence Is No Evidence for a Multiverse

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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.

https://www.jstor.org/stable/2254310?seq=1

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I’m not very convinced by these arguments.

For instance, with the casino example, while it is true one cannot assume that the particular individual had been playing all day, it would be correct to reason that (unless there is a pandemic going on) there are thousands of people playing dice in thousands of casinos around the world, and so it is a certainty that someone somewhere would walk in at the moment someone was throwing a double six.

Similarly, with the Joker story, if the Joker had set up an infinite number of possible victims with an infinite number of chimps, at least one of the possible victims would get lucky. Now, we know this is not possible with chimpanzees. But to say it is also not possible with universes would be to beg the question.

I find it hilarious that you find it intuitive that, given enough monkeys randomly jabbing away at typewriters, that one of them is bound to accidentally write a bit of English.
Because the analogy simply begs the deeper question --how did your monkeys and typewriters and the conventions of the English language arise randomly? And, by analogy, is the universe we live in just “a bit of English?”
Remember, the official analogy has them collectively producing all the sonnets and collected works of Shakespeare-- that’s a closer analogy to the actual odds against life arising by chance in a completely undesigned universe. The simpler analogy may beg intuitive credulity, but it does not serve as an adequate comparison to the actual reality of the universe we live in, any better than my next claim --that this answer was actually typed out by my dog, and I only discovered it in time to keep him from accidentally erasing it, instead of posting it-- because that requires a mind with intentionality driving it, so my story doesn’t make a good analogy, either. So, its bite isn’t as good as its bark… or, is it? ;o)

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.

This is a good question.

This is still my own thought on the subject:

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.

I cannot help but think that this perpetuates its own fallacy. Are these the probabilities of all life (or for that matter all potentially-intelligent life), or merely the probability of life that reasonably closely resembles our own (carbon-based, oxygen-based metabolism, etc)?

Assuming, for the sake of argument, that there is a wider range of potential lifeforms, it would seem to be unavoidable that the lifeforms that evolved into existence would be ones compatible with the universe’s constants.

If the universe had different constants, could very different lifeforms have evolved? That would seem to be a very tricky question. But it is, I think, a question that needs to be answered before we can draw any conclusions from calculating the odds of the universe supporting life.

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The fairest statement I can make is that we don’t know how many universes there are. There is simply no way of knowing how probable or improbable our universe is. There is also the rather obvious detection bias in the data since we would only observe a universe in which we could exist.

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I agree, intuition is no help here. Math entails that conclusion though. Given more rolls of the dice, the probability of obtaining some particular result increases. With enough rolls, it will get close to a certainty.

Now here I have to say your response got hopelessly lost. What is the monkeys, typewriters, and conventions of the english language in your analogy, supposed to be analogous to?

We are posed the question why the constants of nature have the values they do? Nobody says there are actual literal monkeys with typewriters hammering away to write the constants. It is just an analogy to the idea that they somehow could have arisen randomly, perhaps from some deeper physical phenomenon. Nobody knows whether that is true of course. It is not actually known whether the values can even change, what could make them change, nor even if chance plays any role in that at all.
All of that is pure speculation, including the idea that immaterial cognition in the absence of physical brains can just wish for it hard enough and then the constants somehow pop into existence. That too is a total fantasy, and nobody knows that either.

The problem with the God hypothesis is that it doesn’t solve the probability issue. In order for the God hypothesis to explain the very improbable constants of nature, you have to posit a very specific and particular God with the attribute of wanting to create our specific set of constants of nature. And we can imagine Gods that want to create infinitely many other universes than this one, so we’re still left with the probability problem: Out of all the possible Gods that could have existed, we got one that wanted this set of constants? What are the odds?

The fine tuning argument cannot constitute a rationally persuasive argument for the existence of God, as it doesn’t actually solve the problem it is posed to solve. You’re still left with an incredibly low probability.

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I didn’t say it was intuitive. It’s just rational. That “enough” is enough is simply tautological.

That is another thing I would not claim. Those things did not arise randomly.

When it comes to calculating odds, mathematics applied to solid data works much better than gut level intuitions.

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Strangely devoid of logic, that statement.

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For reference, what statisticians call the Gambler’s Fallacy has a gambler playing a “fair” game, and able to double-down if he loses. For example, the probability of winning is 50% and the payoff is twice the bet. In theory the gambler can double-down with every loss, and eventually break even with a win. The fallacy is this assumes the gambler has an infinite amount of money to bet.

Edit: What the SciAm article calls the Gambler’s Fallacy is thinking that dice have “memory” of previous rolls, and a run of bad luck mean good luck is more likely to happen with the next roll. Now I’m off to read Jstor …

TL;DR: The house always wins.

Of course you know I was directing my comments at Dr. Swamidass, right? – which is why they are not responsive what you wrote.

I find it hilarious that you think that’s hilarious when you clearly don’t understand.

I also find it hilarious that you think it’s in anyway related to this:

No, I don’t. And since Joshua has not expressed any views in this thread, and your comments were directly pertinent to what I wrote, I think my presumption was justified.

Casinos try to take advantage of this by posting the last 10 results on a roulette table. People can be fooled into thinking that red is more likely if the last 5 rolls were black.

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Why? Prove it.

If my brain is working today, this is only the case if you know the number of rolls ahead of time. If you don’t, each probability is the same. We do not know of other universes; therefore, this universe is extremely unlikely.

It’s odd you’re criticizing him because he added no comments, just quoted from the article. Maybe you didn’t realize that was the case. The point of the article is really that this is not intuitive, but if it happened, you have no choice but to go with it.

Covered in the Scientific American article.

If you think your argument is logical, then you should also be convinced by the following:

If one uses logic one finds invisible pink fairies.

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A few shots of Smirnoff also works.


[Sorry. It’s Friday. And I don’t even drink.]

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I didn’t say it had anything to do with logic, @Rumraket did. I said it was my thoughts on the subject.

You didn’t make a logical argument, you just made an assertion.

Uhm, QED.

No. Think of it this way: The odds of rolling 6 on a fair die is 1 in 6, right? Okay, suppose I tell you you get more than one roll, but not how many more. So you don’t know how many additional rolls you get, only that it’s more than one. That means at least two rolls. So what are the odds of rolling 6 if you’ve got two or more rolls? More than 1 in 6 of course. It has to be at least the odds of rolling a six in two rolls, wouldn’t it?

I think you’re off your game today. What follows the word ‘therefore’ doesn’t actually follow what precedes it. Our ignorance entails no particular or range of likelihoods of the universe we inhabit.

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The logic takes you to intelligent cause. God is defined as an intelligent being. How do you define invisible pink fairies?