What is so improbable about a fine-tuned universe for life

[lpetrich]

Looking over time does not give very good results for habitability, either. Let's look at our planet's past. We emerged in an environment with lots of convenient-sized land and aquatic animals, and also plants to gather: fruits, nuts, grains, leaves, shoots, and roots. We also had plenty of oxygen to breathe. How far back can we go?

Most of our food plants are angiosperms, and they dominated the land flora since the early to mid Cretaceous, roughly 130 - 100 Mya.

Before that, the most common land plants were gymnosperms like conifers and cycads. Some of their seeds are edible nuts, seeds like pine nuts. But it would be hard to get much of a harvest of them. One can make soup from pine needles, but one would have to boil it down to make it more concentrated. Ferns were also around, and some ferns have edible rolled-up stems or fiddleheads. Some ferns also have rhizomes, sort of thick roots, and some of them may be edible.

Ferns and seed plants first appeared in the late Devonian, 360 to 385 Mya, and before them were more primitive land plants like lycopods and mosses. Around the beginning of the Devonian, almost 420 Mya, land plants were very short and mosslike. The first ones likely lived around 480 - 450 Mya, in the Ordovician.

In the water, macroscopic algae likely went back much further, well into the Proterozoic, but it's hard to find much on eukaryotic-macroalgae fossils. But there was another kind of "algae" that went back into the Archean, over 2.5 billion years ago: stromatolites. These structures are built up by cyanobacteria, blue-green "algae", by trapping sediment. So one have to scrape off top layers and strain out the sedment. But there was likely a lot of cyanobacteria in the oceans and lakes that was much easier to extract. In any case, having nothing but Spirulina day in and day out might get monotonous.

Farther and farther back, it gets worse and worse. Like trying to harvest slime from hydrothermal vents.

 

[Gun Nut]

It is improbable that a giant redwood tree can grow from a small seed without a guiding spirit.

Totally. Trees can't grow on their own. The oak tree, for example, need squirrels to bury their acorns and forget where they buried them for another Oak tree to grow. It also needs sunlight to guide it upward.. as well as gravity to tell it which way to "look". Such a small percentage of trees actually grow from their seeds that "improbable" is a good term to use.
Flowering trees need the hands of birds bees and butterflies to propagate. It takes a village to raise a tree... a community of life forces inadvertently working together. The fig tree, in particular, has an amazingly complex set of interactions with the rest of the forest.. it is known as "the queen of the jungle", or something like that.

It is improbable that a thinking feeling human can grow from egg and sperm without a guiding force.

Another village, for sure. /i trust you have served that role as the guiding force for someone's child, even if not your own. If not, then you have lived a useless life.

 

[lpetrich]

Having taken on plants, I turn to animals. We emerged amidst a lot of land animals, all the way up in size to elephants (the most massive) and giraffes (the tallest). Our planet has had a good range of size in land animals ever since legged vertebrates crawled out of swamps in the mid-Devonian, roughly 390 Mya. The present-day size champions are elephants, and some extinct ones were larger than present-day ones. Present-day ones: African savanna (m: 3.20 m, f: 2.60 m), Asian (m: 2.75 m, f: 2.40 m), African forest (2.20m), largest one on record (shot in Angola in 1956: 3.96 m). Although most recently-extinct elephants were similar in size to present-day ones, some of Palaeoloxodon grew to shoulder heights of 4.5 m or even 5.2 m.

The land-mammal size champion was Paraceratherium, a rhinoceros relative that lived in the Oligocene, some 38 - 24 million years ago. It had a relatively small hornless head on a neck somewhat longer than its head. It could reach 4.8 m in shoulder height. The all-time champion was some sauropod dinosaur, the ones with elephant-like bodes and long necks and long tails, but it is hard to get good numbers for the largest of them, since their remains are rather fragmentary. But the larger ones were at least as large as the largest elephants or that Oligocene super rhino, and certainly had much longer necks and tails.

The ancestors of the land vertebrates crawled out of the swamps around the mid to late Devonian, and before that were land arthropods -- insects and arachnids and myriapods. They were mostly in the size range of present-day land arthropods, though some of them could grow very big, like the late-Carboniferous giant millipede Arthropleura, as much as 2 m long. The first known land-arthropod fossils are in the late Silurian, about 419 Mya, and some likely land-arthropod footprints are even older, in the late Ordovician, around 450 Mya.


Looking in water, one can do better. The oceans have had large fauna since the Cambrian, some 500 million years ago, though back in the Cambrian, the largest animals were the anomalocaridids, at as much as 1 to 2 m long -- longer than a present-day lobster, even if not much by the standards of later ocean fauna. Going into the Ediacaran, one of the largest animals was Kimberella, as much as 15 cm long, making it the size of a present-day garden snail without its shell. It lived around 555 - 558 Mya, and putative macroscopic animal fossils have been found as far back as 610 Mya.

 

[Shake]

Our Universe does have some features that are rather convenient for us. Like three space dimensions and one time dimension.

• Fewer than three space dimensions means much less possible complexity.
• More than three space dimensions means no stable orbits possible.
• More than one time dimension means that closed loops in time are possible.

There are various other features that are convenient for us, like some Standard-Model parameter values.

In our Universe, dineutrons (nn) and diprotons (pp) are borderline unstable, while deuterons (pn) are borderline stable. If deuterons were unstable, then it would be *very* hard for nucleosynthesis to work. If dineutrons and/or diprotons were stable, then nucleosynthesis would have been very different. Stable dineutrons would make it easier for primordial nucleosynthesis to make elements heavier than helium, while stable diprotons would make the Universe mostly helium and heavier elements.

For that stability to change, the nucleon-nucleon interaction would have to have a different strength, and that would happen from the up and down quarks having different masses relative to the quantum-chromodynamics (QCD) mass scale. Lower quark masses means a longer-distance NN interaction, and stronger interaction, while higher quark masses means a shorter-distance NN interaction, and weaker interaction.

Another curiosity is that the mass of the up quark is less than the mass of the down quark, in contrast with the charm quark being more massive to than strange quark and the top quark being more massive than the bottom quark. This makes neutrons (udd) more massive than protons (uud). But if protons were more massive than neutrons, then the early Universe would produce more neutrons, and protons would decay into them. This would make the main hydrogen isotopes deuterium and tritium (pnn), and that would affect nucleosynthesis in stars.

Would you say that this universe is improbable if it were the only one? I have found some scientists claiming it is and that there needs to be a designer or multiverse, and I have found some scientists that think that there is no coincidence with no explanation needed.

For the sake of full disclosure, let me start of by saying I've only read most of the first page of this thread, and what are currently the last two, so I apologize if someone has already made the point which I am about to bring up.

ryan, you keep bringing up the "improbable" nature of this universe (or really, any other). What struck me in my early readings of this thread is a point you seem not to have considered: improbable does not mean impossible. Several years ago, a biophysicist published a paper suggesting that life was inevitable here, and according to this article, he seems to have followed it up with some experimentation which backs up his ideas. Time is certainly a factor here, in that even with really small odds, if you have enough time, the improbable becomes possible.

 

[Learner]

Doubtful. Again, science would be of no use in a fallacy like this one, so any alleged deep dive would just be a misperception as to what is actually going on for that individual. At best, the only "science" being applied in any way to any of these ID theories would be probability theory, but that doesn't get you anywhere near any kind of valid conclusion.

Everything about ID/Anthropic Principle, whatever you want to call it, absolutely hinges on the non-existent link between framing something in an improbable light and then saying, "Dude, come on. It's so improbable that it therefore must have been designed/created/willful/etc."

Iow, ultimately, it's all essentially a combination of post hoc, ergo propter hoc and a great big argument from incredulity.

It doesn't matter how many times its reframed, it will always only be a fallacy.

I'm doubtful you really are doubtful of what I previously posted, in that , there are scientists out there who do change their POV's (I am only assuming this as you didn't ask me for any links to these individuals)

This is central to every attempt to appeal to science--to the rational--to try to bolster faith (i.e., the irrational). Whether its done by a Bishop or just someone raised in a cult like Christianity--no matter how casually--whose programming gets triggered later in life by some tragic event or otherwise difficult period. The "no atheists in a foxhole" cliche that nevertheless is true for a lot of dormant cult members, shall we say.

Even to me as a theist, these fellows are not worth my time or interest. Obviously lacking the credibility to be taken seriously.

Interesting if true, considering that, as a theist you necessarily must just accept that magic is real, so why would an argument from incredulity phase you in any way? It, too, is the basis of all cult programming and passes for "evidence" in all cult beliefs. Indeed, its foundational. Without the "Divine fallacy," there would be no Christianity; no theism period.

Sure ...but for those who are actually attemting to apeal to science. Those you point out to me , I may well agree with you there.

I'm talking about dishonesty and any such false claims as well as apealing to science and so on which is not Christianity (as it is , according to Jesus's version of course ... to be truthful etc..etc..). No probs if you need to keep bringing in religion , if its something to grasp onto, as an argument in the fine-tuning discussion , otherwise , see you in the religion section .

 

[steve_bank]

No one says science is absolute truth, error free, a moral authority, and free from corruption. In the long run it is self correcting. Evidenced by the last 200 years.

In contrast religion seeks to stay the same in the face of clear refutation n of facts by science.

 

[lpetrich]

Let us look at how breathable the Earth's atmosphere was for us in the past.

First, our oxygen tolerance, low end, then high end.

On the low end,  Altitude sickness

Where	Elevation	Tot Press	PP of O2
Sea level	0	1	0.2
Denver CO US	1.6	0.84	0.17
Altitude sickness	2.5	0.75	0.15
Death zone	8	0.36	0.07
Mt. Everest peak	8.848	0.31	0.06
Airliner cruising	10	0.26	0.05

On the high end,  Oxygen toxicity. We can tolerate short periods of extra oxygen, but it affects lung capacity, and the highest concentration that we can tolerate without loss of lung capacity is a partial pressure of 0.5 bar. We get central-nervous-system toxicity at around 1.6 bar.

Turning to carbon dioxide,  Hypercapnia is from excess CO2 intake.

PP of CO2	Time	Effect
0.000280	indef	Holocene until mid-18th cy.
0.000410	indef	Atmospheric concentration as of 2018
0.015	1 month	Mild respiratory stimulation
0.030	1 month	Moderate respiratory stimulation
0.035	1 week
0.040	1 week	Exaggerated response to exercise
0.045	8 hours
0.050	4 hours	Prominent respiratory stimulation
0.055	1 hour
0.06	0.5 hour	Beginnings of mental confusion
0.065	0.25 hour
0.07	0.1 hour	Dyspnea, mental confusion

 

[Koyaanisqatsi]

I'm doubtful you really are doubtful of what I previously posted

You should not be.

in that , there are scientists out there who do change their POV's

That's a common false equivalence, often bolstered by what I would call Pauline cult members (who operate on the "it's ok to lie in service to Jesus" rule). Legitimate scientists follow the science. It is a fundamental contradiction to consider yourself a scientist and yet still hold beliefs in magic. I'm not saying it doesn't happen, of course; humans have a seemingly unique capacity for compartmentalization after all. Nine times out of ten, however, it's either someone claiming to be a scientist, but isn't, or someone whose field of science really has nothing to do with applying that field to the question of magic. Iow, it usually turns out that the "scientist" in question is, like, a geologist or archaeologist, or something equally unrelated.

The cult member, of course, omits this fact and instead tries to leverage the "scientist" part. But see, that's the "tell" of someone who knows (on some level) that their beliefs are bullshit. If you have to go to that extreme--knowingly--then all you are doing is subconsciously revealing the fact that you know it's a lie. That is the essence of the Pauline christianity sect in particular.

Sure ...but for those who are actually attemting to apeal to science. Those you point out to me , I may well agree with you there.

Every IDiot is attempting to appeal to science to hide their cult beliefs.

I'm talking about dishonesty and any such false claims as well as apealing to science and so on which is not Christianity (as it is , according to Jesus's version of course ... to be truthful etc..etc..). No probs if you need to keep bringing in religion , if its something to grasp onto, as an argument in the fine-tuning discussion , otherwise , see you in the religion section .

I'm not sure I understand the distinction you're trying to make. Anyone that is trying to argue that the universe is purposefully "fine tuned" for life is axiomatically making a religious claim (or masking one). Tuning is a volitional act.

Iow, this entire thread belongs in the "religion" section.

 

[lpetrich]

 Geological history of oxygen contains some estimates of the partial pressure of oxygen in the past, and  Carbon dioxide in Earth's atmosphere does likewise for that gas.

Over the last 600 million years, since the mid-Ediacaran, the atmospheric oxygen level has been fairly close to the present-day level, rising from 0.1 - 0.15 bar to the present 0.2 bar. It had a bump in the Permian to as much as 0.3 bar.

Fossil charcoal, its recognition and palaeoatmospheric significance - ScienceDirect -- for plant material to burn: at least 0.13 bar, for plant material to burn too easily: at least 0.35 bar. There is plenty of evidence of both forests and charcoal starting at the Late Devonian, about 380 - 360 Mya.

During all these time, we could breathe the Earth's atmosphere. That was not the case before the Ediacaran. About 850 Mya, the concentration of O2 was 0.02 - 0.04 bar. Before the  Great Oxygenation Event of 2.5 Gya, it was even less, and I've found it hard to find good numbers. In any case, it was far too low for us to breathe.


Turning to carbon dioxide, it varied from 180 to 280 ppm (partial pressure 180 - 280 microbar) over the last 400,000 years. Over the rest of the Phanerozoic, it varies much more. (Atmospheric CO2 and O2 During the Phanerozoic: Tools, Patterns,and Impacts,  Carbon dioxide in Earth's atmosphere). It rose to about 500 microbar at the K-Pg boundary some 65 Mya, and fluctuated around that value until the Carboniferous, some 350 Mya. It then increased to the 4000 microbar (4 millibar, 0.004 bar) in the Cambrian, some 500 Mya.

From that paper, oxygen peaked at 0.32 bar in the Permian (around 300 Mya), and declined to 0.15 bar in the Jurassic (about 150 Mya).

So we could breathe the air through all the Phanerozoic. As to CO2, even in the Cambrian, it was well below the threshold of hypercapnia.

Mesoproterozoic carbon dioxide levels inferred from calcified cyanobacteria -- around 1.2 Gya, it was about 7 to 10 times the present atmospheric level, or 3 to 4 millibars. However, High CO2 levels in the Proterozoic atmosphere estimated from analyses of individual microfossils proposes 4 to 70 millibars. That's 0.07 bar, enough to cause severe hypercapnia.

Precambrian paleosols and atmospheric CO2 levels -- fossilized soils and CO2 estimates from their chemistry. For 2 Gya, estimates 4 o 40 millibar (0.04 bar - well into hypercapnia range). Carbon Dioxide on the Early Earth - estimates as much as 10 bar.

So if the lack of oxygen doesn't get you, the carbon dioxide will.

 

[lpetrich]

Having shown that the Earth's air was unbreathable by us for nearly 4 billion years, most of its history, I consider other environmental difficulties. Habitable Planets for Man | RAND (Stephen Dole, 1964) is a nice place to look.

About temperature, our optimum environmental temperature is around 20 C (68 F). SD decided that a place is habitable for us if its average temperature is between 0 C (32 F) and 30 C (86 F), and if its day-averaged temperatures are between -10 C (14 F) and 40 C (104 F). Notice that our habitable range extends much farther below our body temperature (37 C, 98.6 F) than above it.

Turning to light, our upper limit is around 500,000 lux.  Lux states that direct illumination by the Sun can go up to 100,000 lux.

About gravity, it is hard to move around for accelerations greater than 1.25 - 1.5 g's.

 Nitrogen narcosis comes from breathing too much nitrogen. It sets in at about 3 bar of N2 and gets very bad at 10 bar.

Geological nitrogen cycle and atmospheric N2 over Phanerozoic time | Geology | GeoScienceWorld -- very little change in the amount of nitrogen over that time. But for before that, I've found Geochemical Perspectives Letters - A secular increase in continental crust nitrogen during the Precambrian, Modeling pN2 through Geological Time: Implications for Planetary Climates and Atmospheric Biosignatures | Astrobiology and more a more recent one, [1805.00893] EarthN: A new Earth System Nitrogen Model -- that latter one finds about 2 bar of atmospheric nitrogen before 2.5 Gya and 0.8 bar afterward. So one will not get nitrogen narcosis from the Earth's early atmosphere.

 

[atrib]

I am having a problem wrapping my head around why our universe is so improbable.

For simplicity, if there were, say, a billion possible universes that could have existed and each one is different in some way, then of course the one universe that appears had the one in a billion chance of existing.

I believe that I am wrong because after hours or research, I find my argument aligning with the general public while the scientists all seem to be in agreement and are publicly stating that this universe is too unlikely to exist. The odds are something like 1 in 10^125 or something wild like that.

They claim that it is so unlikely that it warrants an explanation like a multiverse where all the other universes exist too making ours not so improbable (response to the anthropic principle).

We have no data to suggest that our universe is either improbable, or ordinary. That is a fact. Anyone who tells you otherwise is pushing an agenda.

 

[atrib]

It's not bilby. There is little to no dispute that the universe is fine-tuned for life; scientists agree on this. It forces them to evoke a multiverse. But if there is no multiverse, there apparently is a nearly impossible coincidence that needs explaining.

Reputable scientists all over YouTube and in other literature believe this.

My issue is what is it about an extremely narrow range of values allowing life that makes it such a coincidence. There really does seem to be a major problem here, a problem using probability that I don't understand.

There is a difference between the following statements:

1. The universe allows life to exist.
2. The universe is fine-tuned to allow life to exist.

They sound similar, but have vastly different implications. Implicit in statement 2 is the assumption that the universe has a purpose, and that purpose is to allow life to exist. The assumption remains unstated because people use statement 2 to argue for an intelligent designer, and the argument doesn't work if you let slip that you are assuming what you are trying to demonstrate. We have no evidence that the universe has a purpose, other than perhaps to relentlessly move from a state of low entropy to a state of high entropy. And that life speeds up this process.

I think you are reading too much into the words of scientists. I don't know any cosmologists who believe that the universe has a purpose, or that it was created by an intelligent entity. Nor does this belief force scientists to hypothesize about multiverses, as you have claimed. The concept of the multiverse is a prediction from cosmological models like inflation, but we do not yet have the data to conclusively demonstrate such a hypothesis.

As far as we can tell, the universe does not care about humans or the existence of life, because the universe is not a sentient entity. Nor do we have any evidence that the universe was created and/or controlled by a sentient entity, much less that it was designed to support life on our planet.

 

[atrib]

So there are no reputable scientists on YouTube?! You clearly don't know anything about this, so stay in your ignorance.

Name some of these reputable scientists who claim that the universe was designed by an intelligent entity to support life. Kent Hovind would not be included in this group for obvious reasons.

 

[atrib]

I agree. A multiverse is not scientific, but even scientists like to speculate.

I don't know why but there is a large population of legitimate scientists that claim that there is a big coincidence that needs explaining.

The multiverse is a prediction developed from cosmological models based on our observations of reality. It is NOT speculation. Big difference.

I am sure there are many scientists who believe we have to find an explanation for why the universe exists, and why it has the characteristics that it has. But the existence of life is a coincidence ONLY if you begin with the assumption that life is special, and that life cannot possibly exist unless our universe was specifically designed to allow life to exist. You cannot assume what you are trying to demonstrate.

Life exists because the conditions in our little corner of the universe allows life to exist. That is all we can say about the matter. If conditions had been different, then life may not have existed, and we would not have been around to think about it. I am not conceited enough to believe that a virtually infinite universe was created just so I could exist, as you seem to do. Nor do any of the cosmologists and scientists in other fields whose words I have read or listened to.

 

[atrib]

Isn't fine tuning one of the creationist arguments in line with Intelligent Design? Or a variation of the watchmaker argument for ID? It all fits together so well it must have been designed and could not have just happened.


There are credentialed creationist scientists who write books and make videos without bring explicitly religious.

Right now things point to a universe fine-tuned for life.

No they don't.

 

[atrib]

Isn't fine tuning one of the creationist arguments in line with Intelligent Design? Or a variation of the watchmaker argument for ID? It all fits together so well it must have been designed and could not have just happened.


There are credentialed creationist scientists who write books and make videos without bring explicitly religious.

Right now things point to a universe fine-tuned for life.

Yes, that's right.
Secular science is what has provided the evidence which suggests the existence of precision "laws of physics". All the scientific evidence for fine tuning can (if you wish) be seen thru the lens of a religiously neutral explanation for why the universe is the way it is.
A finely tuned universe need not entail any God/god.

You can be an atheist and still accept that there are transcendent laws of fine tuning (and mathematics) which exist, for some reason other than the fiat of a transcendent Law Maker.

And as usual, you are not going to tell us what scientific evidence would lead us or even you to conclude that the universe is fine tuned for anything. Or even what the universe is fine tuned for. How predictable. Yawn...

 

[steve_bank]

Yes they do...no they don't...yes they do...

To Christians their conclusions are obvious and are puzzled when we just don't see it.

 

[atrib]

So you are stuck in my boat which apparently is the wrong boat to be in. Scientists claim that a finely tuned universe is improbable. I am trying to figure out why.

You won't name any of the scientists. Nor will you discuss the arguments leading these scientists to claim that the universe was fine-tuned to achieve a certain purpose. All you do is repeat the claim over and over. I suspect this is because you don't understand what the scientists are saying. Am I right?

 

[fromderinside]

Funny how cause emerges when determined is described. Mary, where is the cart for my horse?

 

[lpetrich]

[1902.03928] The Degree of Fine-Tuning in our Universe -- and Others

abridged) Both fundamental constants that describe the laws of physics and cosmological parameters that determine the cosmic properties must fall within a range of values in order for the universe to develop astrophysical structures and ultimately support life. This paper reviews current constraints on these quantities. The standard model of particle physics contains both coupling constants and particle masses, and the allowed ranges of these parameters are discussed first. We then consider cosmological parameters, including the total energy density, the vacuum energy density, the baryon-to-photon ratio, the dark matter contribution, and the amplitude of primordial density fluctuations. These quantities are constrained by the requirements that the universe lives for a long time, emerges from the BBN epoch with an acceptable chemical composition, and can successfully produce galaxies. On smaller scales, stars and planets must be able to form and function. The stars must have sufficiently long lifetimes and hot surface temperatures. The planets must be massive enough to maintain an atmosphere, small enough to remain non-degenerate, and contain enough particles to support a complex biosphere. These requirements place constraints on the gravitational constant, the fine structure constant, and composite parameters that specify nuclear reaction rates. We consider specific instances of possible fine-tuning in stars, including the triple alpha reaction that produces carbon, as well as the effects of unstable deuterium and stable diprotons. For all of these issues, viable universes exist over a range of parameter space, which is delineated herein. Finally, for universes with significantly different parameters, new types of astrophysical processes can generate energy and support habitability.

In short, the Universe is somewhat fine-tuned for our existence to emerge, but not greatly fine-tuned. Some parameters can easily vary by an order of magnitude or more and still yield habitable universes. Furthermore, we may not even live in the best possible universe for habitability.