If we live in a multiverse, what percentage of universes will be capable of harboring life

Is there a limit on potential physical laws? If we live in a multiverse and if different universes have different physical laws (hypothetical), only a microscopic percentage can harbor life. Has anyone done a guesstimation on what % could harbor life? Is there a limit on physical laws, meaning, can lambda have infinite values or are the values within a set range? I realize that you can have infinite values within a set range, but there are going to be values that allow chemistry and life within that range.

I don’t understand physics well so I’m not sure if this is even a valid question. Point is, if we live in a multiverse of endless variations of physical laws, and assuming there are finite limits on physical laws, what percentage of universes relative to the whole could harbor life? Or is the answer ‘an infinite minority of an infinite majority’ or something?

If we live in a multiverse, the question is essentially meaningless - How can you take a percentage of infinity?

An infinite number. And there’s an infinite number without life. And an infinite number where almost everything else is the same but you spell your SD name with an e at the end.

I hate the concept of the multiverse. Not only does it take away free will, it takes away any point to existence.

It doesn’t matter what you do, because in some other universe you will always do the right thing.
This idea was covered very well in a science fiction short story by Larry Niven-“All The Myriad Ways”

One might suggest that without connectivity and communication between the various incarnations of a multiverse, that what you do DOES matter - because you will never see the alternative acts, nor their consequences. Thus, morality and free will are preserved.

18.36%.

That’s the right answer in at least one universe.

I do know a bit about physics and a few things about biology, and not only do I think this is a question that informed speculation cannot begin to address, I’m not confident that it is a even meaningful question.

All life that we know–which, to date, is exclusively limited to life on Earth which as we observe has a single origin–is chemical in nature, and furthermore based on the six of the most abundant chemicals in the universe (hydrogen, carbon, nitrogen, oxygen, phosphorus, sulphur). Although living forms at even the monocellular level are formed of incredibly complex systems, the basic structures of those systems are formed from twenty amino acids, lipids, and bound and powered by carbohydrates, most of which we can synthesize in the lab (with relatively crude and inefficient methods). It seems likely to the point of statistical certainty that life based on organic chemistry will be found elsewhere and probably frequently in our universe and in any other universe which has similar chemical laws. (Those bemoaning that we have not yet found signs of extraterrestrial life and rationalizing that it must not exist should recognize that we have landed probes on only four extraterrestrial bodies in our own solar system (Luna, Venus, Mars, and the saturnian moon of Titan), only one of which could possibly support a biotic environment with a liquid medium and available hydrocarbons, and have about as much sense of the wider possibilities for life even in neighboring star systems much less the larger universe as a gnat does of Shakespeare.)

We naively assume that life would be chemical in nature and similar to our own fundamental construction of proteins and cellular organization which is reasonable given the lack of other examples but exclusionary to other possibilities of self-reproducing regulated net thermodynamic systems with large scale organization which could, depending on the qualifications you apply, be considered as life. As to universes with other laws of physics, perturbing basic parameters which appear to be arbitrary (to our current limited understanding of fundamental particle physics and quantum field theory) would certainly make chemistry that we know untenable but could be replaced by other organizing systems using different combinations of forces and an analogue to chemical elements, or perhaps even some more exotic combination of organized structures and interactions. It is entirely possible that there are additional forces beyond the four that we know that are suppressed or unmanifested in higher dimensional organizations which could come into play in a universe organized along different physical principles, and we honestly don’t know enough to even begin to speculate on what that might look like.

So, in summary, we have no real evidence to base an estimate of the propensity of life to emerge even within our own solar system, even less to evaluate the vast expanse of the universe that is and will remain beyond our immediate reach for the foreseeable future, and not even a fundamental basis to speculate about life in hypothetical universes with alternative laws of physics and some kind of chemistry-like system of interactions.

Stranger

And one might suggest that this attitude works even better of a smaller scale, where people feel that it doesn’t matter if they do a good job, because someone else further down the line will fix any problems that slip by, and even if they don’t it doesn’t really matter in the long run.

It’s like trying to guess “How many beans are in all my jars?” without knowing what kinds of beans, what size jar and how many jars there are total.

There are infinitely many positive integers. Yet we know what proportion are divisible by 2.

But an infinite number of things does not imply infinite variety. There may be infinitely many universes, but with rather tight constraints on what kind of universe is possible.

I think that there is often a mistaken conflation of the multiverse with Everett’s many-worlds interpretation of QM. The latter does indeed seem to imply that (in some poorly defined sense) all possible outcomes exist. But most versions of the multiverse are based on completely different ideas.

ETA, having said that:

http://www.preposterousuniverse.com/blog/2011/05/26/are-many-worlds-and-the-multiverse-the-same-idea/

But, I think it’s important to first understand how multiverse and many-worlds are completely different ideas before contemplating the deeper (and controversial) idea that they may be the same!

Far from it; not only does it not matter what may happen in other universes, but you have the opportunity to make your universe the best of all possible existences.

As to the concept of other universes, it should be recognized that there are two separate concepts here. One comes from the quantum mechanical notion of simultaneous superposition of possibilities at the quantum level, derived from Hugh Everett’s “relative state” interpretation (note that Everett did not promote the idea that there was a literal “multiverse”; just that we’re experiencing one of a multitude of simultaneous possibilities). In this multiverse, all the laws of physics are the same but the resolutions of individual states fill all possible options, and share the same mass-energy matrix in a state of superposition.

The other is from brane cosmology that there are separate, unconnected physical universes formed from an initial singularity of energy and which deconstructed into different balances of dimensions and physical parameters. In this case, each universe has its own separate mass and energy (which may or may not be infinite in extent) and are in no way causally connected with one another. In this case, the laws of physics may vary wildly and perhaps randomly, and only a very small number of them would have enough of a structure of chemistry or some analog to develop a stable order. This is what people refer to when trying to justify some “anthropomorphic principle” of higher intelligence even though there is no evidence to suggest that our universe is specially crafted for us as much as that we simple have evolved to fit into a universe and world where relatively stable self-organizing systems are possible.

Stranger

I see articles and essays from time to time, speculating on what a universe might be like if some of the fundamental facts were just a little bit different from what they are in this universe, and they often suggest that with slight variations in those facts, life couldn’t exist. Basically, the “anthropic principle” (AIUI) says that all sentient observers must necessarily see a universe where life can exist because those are only kind of universes in which the sentient observers themselves can exist. (Duh.)

What I see mentioned less often is that, in a universe with slightly different fundamentals, there’s a good chance that nothing could exist at all (meaning, at least, nothing like “matter” as we know it). Quantum physics tells us that the universe, at some fundamental level, is really nothing more than “complex probability density distribution fields”, all vibrating and interacting in various ways, and that “matter” is nothing more than spots where it gets a little more dense than elsewhere, and becomes somewhat stable and persistent.

Change some basic constants, and that doesn’t happen. You could end up with a universe full of fields that don’t “congeal” to create anything.

What a waste of a universe!

See:
The Known (Apparently-) Elementary Particles

The Known Particles — If The Higgs Field Were Zero

by Professor Matt Strassler. (He has a whole series of on-line essays about particle physics, starting here. – Very clearly written, at a good level for lay audiences.)

shrug
Sure. Fatalism is a thing. So is denial of responsibility. But I cannot presume my mistakes will be corrected - because I have no way to communicate with any timeframe/worldframe where some other actor has intervened - thus leaving me no choice but to muddle through as best I am able.

Which still leaves us with infinity.

But there are orders of infinity. The number of positive integers is countable. The number of possible universes is not.

The number of reals between 0 and 1 is uncountable. But (in decimal representation) we know what proportion start with the digit 3.

We really have no firm idea of the properties of the multiverse - in fact, the term encompasses a numnber of different ideas. I was just making the point that the idea that something is infinite does not imply that we can say nothing about its properties.

The sad thing is, even if this particular universe is semi unique (as in, our neighbors are different enough that the earth doesn’t have life or the same planetary structure, etc), there is no empirical evidence for free will or any physical theories to support it.

The most likely explanation given current knowledge is that the particular atoms in your brain determine what you will do and how you will learn from what you did and thus any future changes, and those atoms are governed by physical laws.

So whether or not you read this post and realize it’s true, or dismiss it because it disagrees with your pre-existing false beliefs is only determined by physics. You didn’t decide anything.

Heisenbergian logic. Except that, it’s demonstrable that decision trees are influenced by experience, so pure randomness is ruled out.

Nobody claims that decisions are random. Just that decisions are nothing more than computation. But if we’re going to go off on a free will tangent, I’d suggest that a separate thread is in order.