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Feb 13Liked by Bentham's Bulldog

Your ideas are incredibly creative and are simply begging for more math and science exposure on your part.

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Thanks

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Interesting, but I think a better understanding of particle physics undermines the premises on which your argument is based. I'm just going to state the physics, even though it probably mostly sounds like magical gobbledygook. But feel free to ask questions.

If classical physics were true, all 4 forces would fall off at the same rate (Force = const/r^2), basically because the force lines spread out, and in 3 space dimensions the area of a sphere is proportional to r^2. But in QFT, there are also corrections due to virtual particles, that can make the so-called "constants" change as you vary the distance/energy you measure them at. (The equations involve a logarithm, so the constant only changes a bit, even over many orders of magnitude. These changes, known as the "renormalization group flow", can be calculated explicitly in the Standard Model; i.e. if you know what the constant is at any given scale, you can figure out what it is at another scale.)

The three fundamental forces of the Standard Model, namely:

- the SU(3) strong force between quarks,

- the SU(2) electroweak force, and

- the U(1) hypercharge force

actually DO all have roughly similar sizes! (The elecromagnetic field we know and love, is actually a combination of the SU(2) force and the U(1) force.) If you use units where c = hbar = 1, you can make a dimensionless constant, and then (if we extrapolate them from the LHC scale back to the Planck scale, assuming no new physics happens in between) they are all about the same size (roughly in the range alpha = 1/30 to 1/50). But even if we measure them at the LHC scale, their range lies within a single order of magnitude.

The number strengths that are quoted by people like Collins are very phenomeological low energy measurements, that are affected by the fact that the strong force becomes confining while the weak force becomes spontaneously broken by the Higgs. For purposes of this conversation, those numbers are insufficiently fundamental, and you should be considering the number range in my previous paragraph.

What about gravity? This is sometimes quoted as being about 10^40 times weaker than the other forces. But this is a meaningless nonsense claim, since it compares quantities with different units. The problem is that gravity is unique in that the size of the force depends, not on a charge, but on the MASSES of the two objects (ultimately because it is mediated by a spin-2 boson, not a spin-1 boson). This means you have to specify what mass of objects you are considering, or you can't even compare it to the other forces! This is a somewhat arbitrary choice. If the two objects both have the Planck mass, then the force is about the same strength as the other forces. if they are stars, it would be much bigger. If they are electrons or protons, then you get numbers like 10^(-40).

There are some legitimate fine-tuning questions in the vicinity of this big number, but it ought to be expressed as the question of why the electron and proton are so light compared to the Planck mass. They turn out to be light for completely different reasons, though. The electron is light because it couples very weakly to the Higgs boson (nobody knows why, since this is an arbitrary parameter, but it is "technically natural" in the sense that if you assume it starts off small, then quantum corrections don't mess that up), and also because the Higgs boson is itself fine-tuned to be very light compared to the Planck scale (this is "technically unnatural" and easy to spoil with quantum corrections, and requires fine-tuning to about 1 part in 10^30 in the fundamental constants, unless supersymmetry exists).

For the proton, on the other hand, there is no fine-tuning required to make it light, due to the fact that as you go down in energies, the SU(3) force gradually inches its way up to being strongly interacting, and then as soon as it gets strong enough (when alpha ~ 1) there is a confinement phase transition, and the proton appears at around that energy scale. In other words the Standard Model predicts that the proton mass should be about e^(-50#) where the # is some order unity number that I'd have to do a calculation to know what is, and the 50 comes from the fact that the strong force is about 1/50 at the Planck scale. But it is a notable coincidence (and anthropically important) that the proton mass ends up being so close to the electron mass.

Note that none of the physics in the previous 2 paragraphs had anything to do with gravity per se (other than stopping the fine-tuning analysis once we down get to the Planck length, since smaller distance scales might not exist). So saying that "gravity is 10^40 times weaker than the other forces" is just not a good way of putting things.

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Let me first say that I'm a huge fan of your blog! In fact, as I began to take theism more seriously, it was one of the big things I read that made theism start to seem more plausible.

I'm not a physicist and so I might be really confused here, but that said, I'll respond based on my best understanding. Your statement that the fundamental forces, SU(1-3) are all roughly equal but then produce non-fundamental forces seems to have the same problem as explaining fine tuning by saying that there are more fundamental laws: namely, it's sort of weird that the more fundamental laws are such as to produce finely tuned higher order laws. Or, in this case, it's weird that the more fundamental laws are such as to produce higher order laws of radically varying strengths.

Re gravity: even if they're different units, it's weird that in normal circumstances the forces are such as to have a few forces dominate on the small levels but then become entirely irrelevant on the large levels. If the prior in the various forces are sampled over the same probability distribution, it would be unlikely that some would dominate the world of small things, others of big things.

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Thanks for the compliment! I'm happy to hear my blog was helpful to you (though I already saw your flattery of me on an earlier blog post.) But on the other hand, so much for the idea of using your philosophical intuitions as an independent check on my own... :-)

As in all cases of Design arguments, there is a question of whether finding a mechanism should defuse the sense of designedness, or put one in awe of the mechanism itself. (I think you made a similar point in a recent article about Darwinian Evolution.) Both responses certainly exist as emotional reactions in various people. Which is more intellectually credible probably depends on the details to some extent...

From this perspective, there are certainly even more astonishing things than just different forces mattering more at different scales. One particularly awe-inspiring case is the baryogenesis, which is the question of why there is more matter than antimatter in the universe. We don't actually know for sure! But the currently most plausible (IMO) scenario is called "leptogenesis", as it turns out you only need very conservative extensions of the Standard Model to make this work... but the exact mechanism would proceeds in a Rube Goldbergy way, involving a tour of all of these features (+ more):

1. Neutrinos being their own antiparticle (not known to be true but probable for other reasons, as this allows us to explain why they are much lighter than other particles)

2. There being at least 3 generations of matter (quarks & leptons)

3. Chiral anomalies which are very subtle ways in which symmetries that are valid in classical field theory are broken by quantum effects.

4. The ability of gauge fields to form topologically nontrivial twists called instantons.

As I indicated, this makes me feel awe, but it also seems much harder to quantify numerically than the standard fine-tuning arguments are.

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Thanks for the reply. I thought you'd gone...awall (pun intended).

I think that whether finding a mechanism defuses the argument depends on whether the mechanism has a higher prior probability. So evolution partially defuses biological design arguments, because the prior probability of the ingredients needed for evolution is higher than the prior probability of, say, antelopes just appearing for no reason.

I think your example of leptogenesis is very impressive and that's definitely an impressive kind of fine-tuning. I agree that it's a bit hard to quantify numerically, but we're all Bayesian here! It's also hard to quantify the prior of an antelope arising by chance, but prior to discovering evolution, the argument from biological design was obviously very convincing.

I don't think the disharmony of the forces is anything like the most impressive argument for God--fine-tuning is much more impressive. But it's an interesting feature that does seem indicative of good design--there are no redundant or unnecessary laws in physics it seems.

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Sorry for the delay in replying... all my travel plans ended up being in the same month, so a lot of stuff got derailed. (On the plus side, I got to view my 2nd total solar eclipse, which involves an interesting fine tuning of its own---the sun and the moon are very close to the same apparent angle in the sky. Not sure how much weight to place on this but it is certainly an odd coincidence...)

Your Bayesian account sounds about right. Except I would suppose that the important question is not so much whether the mechanism has a higher prior probability as the previous state of the art (as if it didn't, we wouldn't accept the proposed mechnism being valid in the first place). The question is whether it is high ENOUGH to avoid the need for further design. (Or rather, whether it is plausible that the hypothetical limit case of scientific explanation would have this property.)

Regarding all 4 forces being necessary, there is actually some discussion in the literature about whether the weak force is truly anthropically necessary, if you are permitted to tamper with other things at the same time. See here:

https://en.wikipedia.org/wiki/Weakless_universe

Although I suspect that probably with an increase of understanding we will realize that it is indeed needed. And of course, to falsify the absence of unnecessary forces, the force would have to be "measurable" without being "important", but of course these two things correlate to some extent.

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Unrelated, but I have a YouTube channel where I chat with cool people about interesting things (mostly related to philosophy). Would you want to appear on it an discuss fine-tuning and the Bayesian case for the resurrection?

https://www.youtube.com/@deliberationunderidealcond5105/streams

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I'll consider it. Let me get back to you about it.

(Certainly I would be more interested in a conversation than a debate, as I think the latter format tends not to be as useful for truth-seeking.)

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No worries at all. I mostly just wanted to make an awoll pun. I also found seeing the eclipse very cool!

Right, the lower the prior of the mechanism, the more plausible theism is.

Re the weak force, that's interesting! Though if you need to tweak other things, it still seems relevantly like an example of fine-tuning. To give an analogy, suppose that you see a mouse trap with four important components that all work together to give rise to trapping a mouse. Even if a mouse trap could in theory be made with three components, it's still evidence of design, because the prior probability of that particular mouse trap--needing those 4 components--arising by chance is very low.

This is why the best version of the fine-tuning argument, in my view, is about this broader conceptual point--by far the simplest physical systems and the vast majority of total physical systems produce nothing interesting. We got a world that does interesting things. That's super implausible. And a multiverse doesn't solve the problem because it's still one of those physical systems that does something interesting!

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I agree that the last point is quite important. You might call it a "vanilla" or "root node" Design argument.

One class of systems, unrelated to QFT, where this has been explored is cellular automata. For example only a small minority of cellular automata seem to be in Wolfram class IV where complex structures can persist over time and interact in interesting ways. Although even then, this isn't good enough. For example, the Game of Life is known to support universal computation, but put one glider in the wrong place and the computer melts into chaos.

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If there were a redundant or basically irrelevant force, would we even know of its existence? This is the issue with other kinds of arguments for theism based on laws- we wouldn't know of laws that don't matter.

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I address that in the article.

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> You might think that there are these mostly impotent laws. But that’s a less simple hypothesis. It requires positing more fundamental stuff. I guess maybe the way out of this is to posit that the laws result from more fundamental stuff, so positing redundant laws doesn’t require positing anything fundamental. But this requires believing something speculative about physics for which we have no evidence. I’m hesitant to do this.

If I understand you correctly, you are saying that because of Occam's razor, any potential explanations for what we don't know are automatically more unlikely than God, because we would be positing an additional thing. However, if we assume there IS an explanation, and we just don't know what it is, then how would we know whether the naturalistic one is more or less likely than God?

I'm uncomfortable with this way of thinking, this feels very God-of-the-gaps to me.

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My claim is that if there were other seemingly fundamental laws similar to gravity and electromagnetism, the physicists would probably have realized that.

The God-of-the-gaps charge is mistaken. All reasoning based on evidence will start by looking at a gap in our understanding, before pointing out that the explanation that can be given accounts for it. The reason to believe in evolution is that there is a gap in our understanding--why there are transitional fossils, a common genetic code, and much more--and a theory that explains it. But theism is the same.

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I was alluding to the concept of a "theory of everything" in physics, rather than say a new fundamental law. It seems plausible that there could be an underlying reason like this for the laws being the way they are.

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There could be, but there could be a different fundamental law that results in the laws of physics taking on any of a wide range of possible values. Thus, the odds that the fundamental law would get harmonious values is very low.

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You talk about god repeatedly yet use different definitions. Just based on your arguments alone it seems strange to me that you assign such high probability to Christianity in particular. Also, a bunch of the evidence you provide, for example that laws, require many other types of arguments that are epistemically probable but there are dwindling probabilities, and it seems like you may not be accounting for those—not a critique just making sure you’ve taken these into account. Finally, the very idea that you’ve radically shifted your opinions so fast should also tell you something about your epistemics—presumably your margin of error should be much larger until you’ve sat on these ideas for a while.

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I have not used different definitions.

Not sure what this means: "Also, a bunch of the evidence you provide, for example that laws, require many other types of arguments that are epistemically probable but there are dwindling probabilities, and it seems like you may not be accounting for those—not a critique just making sure you’ve taken these into account."

Not sure exactly what you mean by margin of error. I think it's both likely that my credence will change a lot in the future and is different from the optimal credence.

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This is not a “new” argument for god. This is like the first argument that fourth graders hear about in favor of god. It’s also identical to all the purportedly “new” arguments you’ve mentioned before: there are things with no fundamental explanation, these things must therefore be explained!

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LOL, what? This is not remotely in the same universe as the argument I made.

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> Thus, if the laws are fundamental, you’d either expect the forces to be of infinite strength or all of similar strength. The fact that we don’t see that is a good reason to think that the laws aren’t fundamental.

This argument is that there is no clear explanation for why laws are the same strength. Therefore we must posit God as an explanation.

> So the question: why aren’t there any irrelevant forces?

There is no fundamental explanation for why there are only 4 forces that impact things, instead of 292928 forces but with 292924 forces with tiny impacts. Therefore we must posit God as an explanation.

You could say this about literally anything, of course. What is the explanation for cheese? Ask why to those explanations, ask why all the way down, and then you will arrive at the same place.

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The claim is that on theism laws like ours aren’t too unlikely but on atheism any plausible probability distribution across possible laws results in the conclusion that laws almost definitely wouldn’t be like ours.

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And this is different from standard fine-tuning... how?

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They're just totally different arguments. This points not to the laws being finely tuned for life but for the absence of redundant laws and the laws being similar strength.

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Both arguments are the same. “We have laws with certain qualities; there is no explanation for these qualities, therefore god”. Listing out all the qualities of the laws in question doesn’t somehow make your argument exponentially stronger against god, in the same way that listing out all the individual fish being tortured in Turkey doesn’t make the problem of evil exponentially stronger.

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