I’m not sure what you are asking.

I assume (?) you mean, if someone started “randomly generating” whole complete minds (why would anyone do that? — as almost all those minds would be miserably insane, owing to the randomness of their interior organization, it would be extraordinarily unethical even to try this, and serve no discernible purpose even to a sociopath: see my discussion of this problem vis-a-vis Bostrom’s analogous argument), could they “by accident” generate an exact (?) copy of one of us in this universe.

The answer is in logical terms yes (i.e. that has a nonzero probability) but in practical terms no (the number of random minds they’d have to generate, to even at all likely get even one such lucky coincidence, is so vast there is unlikely to even be enough material in their universe to attempt it, and almost all of the minds they generated in the attempt would correspond to no one anywhere else, and of those that did, almost all of them would be predominately fictional, e.g. like versions of “you” with in many respects different properties and memories and so on, as fictionally generated by this hypothesized randomizer), and in general terms moot (as there would be no causal connection to this universe, it would not numerically be any of us, but a copy of us, and there would be literally no way to know which of the umteen trillions of random minds generated corresponded to a real mind anywhere else, especially among all those “fictional versions of you” there would also then be for example, whereas all the minds thus generated would know, eventually, that all the things in their mind, e.g. all their memories, were fake and thus did not causally correspond to any real person anywhere—thus any chance coincidence of it would not only be indiscernible, but meaningless).

On that problem see my discussion of Boltzmann Brains in The God Impossible.

Could this still apply on a pan-universal scale? In other words, could beings in another universe, with sufficiently advanced technology, simulate many different brains / consciousnesses, and, even if through sheer coincidence, end up ‘re-creating’, so to speak, the mind / consciousness of someone in a different universe that had previously died? If so, then that would be something like ‘travelling’ to a different universe. Even if nothing physical at all could go to another universe, but one’s consciousness could, it would be close enough to the real thing.

Its an intriguing possibility and I’d be very interested to hear your thoughts on this.

Of course. It just follows from every viable cosmological theory that has held up to date. And all those theories are well enough evidenced to trust something in their same mold will turn out to be true (which is why cosmological scientists are pitching their hat at them). But this is a philosophical conclusion, not an established scientific fact.

In other words, we have not yet proved which cosmological theory is correct; we just have theories, like chaotic inflation, ekpyrotic cosmology, conformal cyclic cosmology, nutshell theory, and so on. These all have evidence for them and explain observations very well, but we haven’t “proved” which one is true, or if some other is (though the field of possibilities has been pretty well exlpored by now, so if some “other” theory turns out to be true, odds are, it’s going to look a lot like these). This is largely because we lack a unifying theory of relativity and quantum mechanics. But, right now, every viable peer reviewed cosmological theory that still remains in contention logically entails multiverse theory.

That is extremely unlikely to be a chance coincidence. Therefore, philosophically, some form of multiverse theory is far more likely than not to turn out true.

Follow the link I gave you for five other converging arguments to the same conclusion.

There is really no reason to think there isn’t a multiverse, other than just “stubborn agnosticism.” Philosophically (not scientifically), there is no more viable explanation of the facts so far observed (e.g. as support chaotic inflation theory, currently the leading contender among cosmologists).

It looks quite interesting, but as I understand it, its hardly a consensus among scientists that the multiverse theory is true and its status in the scientific community is still more of a plausible, but far from proven, theoretical possibility, correct?

Well…

First, it’s unlikely alien life even from this universe could visit us. The distances involved are impractical; as far as they could count on, we’d be extinct by the time they even knew we existed, and even more so by the much, much longer time it would take for them to even get a vehicle here, for which reason they are very unlikely to even bother trying.

A message would be more likely, but even that carries its own impracticalities. Imagine Republicans agreeing to fund the trillions of dollars it would take to build the what-they-would-deem-useless transmitter capable of even getting a signal out of the heliosphere (they won’t even spend trillions on useful shit)—and if we wouldn’t, we can’t expect anyone else would. Worse, as Hawking noted, it probably would not even be wise of us to do that even if we could fund it (do we really want to tell what would have to be invincible imperialists where we are?). There is a reason Sagan had to effectively invent time travel to make Contact even scientifically plausible (and all that involved was a signal—no aliens came here—and the convenient McGuffin of an alien base on a star only 25 lightyears away, a laughable improbability).

Second, multiverse theory is almost certainly correct. In fact, there is no plausible cosmological theory today (as in, actual scientific theories in the actual science of cosmology; not creationist claptrap) that doesn’t entail it. It’s no longer conjecture. It follows automatically from every viable Big Bang theory now.

Third, no. Any transition state between universes in any currently plausible multiverse theory is impassable to any complex structure, or indeed even a signal. Any such thing would be destroyed by any Big Bang event or Penrose scale shift, for example. It would be the equivalent of aliens trying to fly into a superheated black hole (a near singularity state at hundreds of trillions of degrees celsius), which would crush and disintegrate their every atom into randomly scattered photons—and expecting to come out the other side as anything but randomly scattered photons immediately swamped into the static of background radiation. “Death even for the dead.”

If so, how, if at all, would that effect the chances of alien life existing? AND, could alien life from other universes visit us in this one if sufficiently advanced [or vice versa, could we visit them]?

I really don’t see any relevant remark in that enormous word wall. You aren’t applying Bayesian reasoning in any pertinent way here. Both sides are summing vast ranges of expected outcomes to arrive at a relative epistemic probability of competing causes; so singular “thermodynamic probabilities” have no relevance to this discussion.

The only probability that matters is the total probability of any abiogenesis event given h and ~h in conjunction with all the evidence e (which includes the size and age of the universe, and the fact that Earth life even began with a single molecule in the first place, and remained unicellular for a billion years thereafter, and so on).

It’s all pertinent, yes.

Don’t get me wrong, Richard, I AGREE with your article almost in its entirety. My fundamental objections are with the entire discussion, where I would expect that we AGREE that it is absurd to even be forced to hold it in the first place, and to a lesser extent to the degree of precision you use in your estimation, neither of which render it fundamentally incorrect or useless. As you yourself say, you only wrote the article out of frustration.

After all, it is a discussion concerning probabilities of events not in an ensemble of observations in one Universe, it is a discussion of an ensemble of possible UNIVERSES in an entirely imaginary super-universe, where by the nature of the problem, our experimental access to “evidence” is limited to a single draw from an urn full of Universes, metaphorically speaking accompanied by pure fantasy describing the urn itself and the way Universes “must” be distributed therein. This is a pure, well known abuse of the anthropic principle, and it means that you will never agree on the unwritten priors which are NOT COMMON to the two hypotheses you compare. You base your estimates for the probability of abiogenetic life on what you called (b) in your linked discussion of Bayesian fallacies — the unwritten, empirically supported priors of the scientific worldview — showing that given those laws as we best believe them to be on the basis of evidence so far, it is at least not thermodynamically unlikely. But the competing hypothesis isn’t that life has an abiogenetic supernatural origin, it is that the laws you used as (b) were incomplete, and of course — they ARE incomplete — in a very specific way.

My point is that even if your SPECIFIC assumptions in the realm of (b)are completely incorrect, and your estimates are thereby way off, the real conflict is between (b) and (not-b) where (not-b) includes a supernatural entity. Your specific assumptions DO have specific empirical support, but if I wrote you and said that your computations weren’t very good (as I did) it hardly matters, as we agree that it is a mistake in Bayesian reasoning to add specific conjunctions in (b) that have NO empirical support and that are NOT consistent with the vast bulk of (b), like “a supernatural entity exists that can do whatever they like with the laws of physics”. Logically, it is entirely possible that your estimate for the probability for abiogenetic life could be entirely mistaken and that it could be based on assumptions that later research proved to be completely incorrect (so (not b) is in fact correct) without SUPPORTING the alternative hypothesis of (not b, s) for a SUPERNATURAL superphysical cause of life.

I’ll try to explain this one more way. No matter what specific event one chooses, it is easy to show that the prior probability of that event (given (b)) was absurdly, thermodynamically low. Seriously. Any microstate is thermodynamically improbable, in physics, in the limit of lots of “stuff” going on. The probability of my writing this reply to you was a priori as close to zero as one could ever hope if it were estimated twenty years ago when we hadn’t even “met”. Yet it is obviously absurd and a BAYESIAN fallacy to assert that the existence of this reply, when physics itself predicted that the probability that it would be written was thermodynamically zero for nearly the entire lifetime of the Universe, is evidence that physics itself is FUNDAMENTALLY wrong and this reply could only have come about if a supernatural God predestined it to be written by selecting very special initial conditions for the Universe using, um, “super-physics” in a “super-universe” to select just the right “physics” and initial conditions as well.

This argument isn’t even consistent as it (as you know and state) replaces one supposedly unlikely thing with something that USING EXACTLY THE SAME CRITERION FOR EVALUATION is even MORE unlikely. Ultimately, it just replaces (b) with (not b, s) by incorrectly asserting that the ONLY way for me to have written this unlikely reply is for a supernatural deity to have ACTUALLY written it at least 13.8 billion years ago and to have wound up the entire Universe in just such a way that I would write it exactly when I, in fact, wrote it. The real problem with even proceeding in this way is that it conflates microstate (or macrostates so ill-defined as to be almost useless in a quantitative estimate of probability with the degeneracy of the actual macrostate — in probability estimates as “proof” that there MUST be God. Every SPECIFIC thing is unlikely, but the existence of unlikely outcomes is not evidence for (not b, s). Even specific things that contradict (b) (and hence support (not b)) are not evidence FOR (not b, s).

IMO that’s the best way to refute silly “estimates” of probability based on the abuse of the anthropic principle, like those of Bergman above, where trying to do numerical computations using incomplete (and probably not exhaustive) physical theories for abiogenesis grants the entire approach a lot more credence than it deserves. Again, I understand your motivation and your frustration, but you leave plenty of gaps for a liar or committed teleologist committed to intelligent design to continue the argument by begging the question, focusing on some specific gap, etc. It’s better just to laugh and say “Go away, kid, you bother me…”

It is worth reading this:

https://www.forbes.com/sites/startswithabang/2017/01/26/how-the-anthropic-principle-became-the-most-abused-idea-in-science/?sh=1adfa5a87d69

It indicates the “good” use of the anthropic principle — we exist, therefore the laws of physics (unwritten assertion (b) in your article on Bayesian fallacies) are (not “are forced to be”, or “are designed to be”, but rather “happen to be”) constrained in such a way that we CAN exist. Given (b), this obviously INCLUDES an abiogenetic, physical origin of life. This use of (b) plus the anthropic principle is strengthened by every “gap” (once occupied by a god, or gods) that has closed as the scientific process has refined set (b) by extending or replacing parts of it with new (not b) hypotheses, without resorting to (not b, s) in the absence of any evidence or POSITIVE reason to do so. In a quite a few cases the anthropic principle has even GUIDED that process as the article points out.

It also points out the BAD way of using it — trying to leverage it into some statement or another about a stastical Super-Urn full of Universes from which our Universe came about as some arguably “infinitely unlikely” sort of draw, where one can argue endlessly and pointlessly about whether or not the unlikely draw was made blindly and randomly or by the intelligent peeking and selection by some even more unlikely supernatural entity existing in a Super-Super-(not-b, s)-Universe in which the Super-urn exists. All without any evidence for the existence of any of this BUT the existence of the ONE Universe we directly experience, where (b) plus a hair of (not b) freedom to explore and extend have proven to be capable of explaining in broad strokes ALMOST everything we can observe, without the need for any (not b, s) inclusions.

This abuses the anthropic principle (and principles of statistical mechanics) by extending it to pure fantasy-land. It is NOT fair to say: “Something exists, and it is easy to see that any sufficiently SPECIFIC something is nearly infinitely improbable given the laws of physics, therefore supernatural God operating outside of the laws of physics to create/choose a that specific something must exist”.

That’s really the essence of all of the teleological arguments for God and they are broken from a Bayesian point of view because yes, they are usually based on utterly indefensible estimates of thermodynamic IMprobability as you quite correctly point out, but also because they are fundamentally inconsistent in their priors, conflating hypotheses and priors and ignoring the lack of evidence for and consistency of the most important prior — (not b, s) — itself.

Using exactly their arguments, the existence of THIS PARTICULAR letter “A” in THIS PARTICULAR reply is proof of God, because oh my, how unlikely is it that this particular reply would ever be written and contain that particular letter “A”. I don’t even think that they would disagree that this IS their argument — they literally cannot fathom the possibility that the fact that ANYthing exists AT ALL is not convincing evidence for the existence of God. All the rest of their arguments are window dressing and sure, people like Bergman just make up numbers and throw in logical fallacies by the barrel full to try to make that dressing pseudoscientific, but it ultimately comes down to the fact that one can NEVER prove (not b, s) without begging the question. All evidence can do in the Bayesian basis of the scientific epistemology is to alter the set that we call (b). Religious belief is fundamentally incompatible with scientific belief, because even God would have to be explained by rules and laws that are consistent with observation. And information theory, but that’s another story, sort of.

This is fascinating that living things can survive in these extreme conditions

https://en.wikipedia.org/wiki/Hydrothermal_vent#Biological_communities

There is also the phenomenon of evolutionary convergence among crabs

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