Universe may not be 'fine-tuned' for life

Fallen Seraph

http://www.technologyreview.com/blog/arxiv/23377/

The chemistry of life may be more robust than we thought against changes in the fundamental laws of physics.
Wednesday, April 15, 2009

The anthropic principle is the idea that the physical laws that govern our Universe are precisely those that allow complex life like ours to emerge. Many scientists have wondered at the balance of these laws, arguing that any small change would alter the universe so radically that life would be impossible. Why is the Universe so finely tuned for life, they ask.

Nobody has come up with a reasonable answer to this question but today James MacDonald and Dermott Mullan at the University of Delaware argue that matters may be more robust than we thought.

Their argument is about the strong nuclear force. Various physicists have noted that if the strong force were just a little stronger, then protons would bind together more readily. That would mean that soon after the Big Bang, most protons would join together to form diprotons, leaving few if any single protons available to form hydrogen. Consequently, chemistry as we know it would be impossible.

But this reasoning fails to take other factors into account, say MacDonald and Mullan. The biggest factor is that protons and neutrons will always bind more strongly than protons and protons, regardless of the strength of the strong force. So although diprotons would form in this universe, they would also tend to decay into deuterons.

So hydrogen (and deuterium) chemistry would be just as likely in a Universe in which the strong force were stronger. (Of course, how the change would affect the the nucleosynthesis of other elements is another question.)

The work gives the lie to some of the more extraordinary claims regarding the anthropic principle. For example, some argue that since we are unable to find anything special about the combination of laws in our Universe, then maybe any permutation is possible. And if any permutation is possible, then perhaps these combinations exist in countless other universes. Of course, the only one we would experience is the one in which the laws are fine-tuned for our existence.

That's an extraordinary line of argument. But the alternative--that organic chemistry is an emergent property of a wide range of the parameters governing the basic laws of physics--is even more jaw dropping.

MacDonald and Mullan's work gives a tantalising hint that this idea might be worth pursuing a little more diligently.

Ref: arxiv.org/abs/0904.1807: Big Bang Nucleosynthesis: The Strong Force meets the Weak Anthropic Principle

I don't frequent these parts as often as I used to, but I just thought that some people around here might find that article some food for thought.

Tigger

just when athiesim was being known as cool

5uspect

That's an interesting finding. It takes the criticality out of the argument.

studiorat

if it was finely tuned another way, possibly all the life forms would still marvel at how finely tuned it was just for them..

Of course if you consider the possibility of infinite different universes, then there's bound to be a few that are composed in such a way as to last long enough and have the right ingredients for all sorts of weird stuff to happen.

Overblood

Universe may not be 'fine-tuned' for life

But no sane person ever thought that the universe was fine-tuned for life. It's the other way around innit.

Dades

studiorat wrote: »

if it was finely tuned another way, possibly all the life forms would still marvel at how finely tuned it was just for them.

Just what I was thinking... Puddle of water, hole in the ground etc!

Doctor DooM

Dades wrote: »

Just what I was thinking... Puddle of water, hole in the ground etc!

Dammit. I wanted the Douglas Adams reference, Dades

But yeah, we evolve to suit our surroundings, not the other way around.

Flamed Diving

I never got this universe being fine-tuned for life argument.

For life as we know it could not exist in 99.9999999999999999999999999% of space.

Fanny Cradock

You have made the same point before, I believe. The fine tuning argument was never about the proportion of the universe that may or may not be habitable to life as we know it. Rather, it is about the very fundamental physical constants that make life, the universe and everything possible in the first place.

Flamed Diving

Fanny Cradock wrote: »

You have made the same point before, I believe. The fine tuning argument was never about the proportion of the universe that may or may not be habitable to life as we know it. Rather, it is about the very fundamental physical constants that make life, the universe and everything possible in the first place.

Yes, I know that, but it could be interpreted, either way.

I figure that the anthropic principle will be revised, in time. We currently don't understand enough about the four forces to be making such arrogant claims. IMO.

kiffer

Fanny Cradock wrote: »

You have made the same point before, I believe. The fine tuning argument was never about the proportion of the universe that may or may not be habitable to life as we know it. Rather, it is about the very fundamental physical constants that make life, the universe and everything possible in the first place.

Yes... and so the question is how much can the laws be changed by and still produce life?
And then the problem becomes do we mean life as we know it or some other form of self-replicating reproducing ... entities.

The basic answer seems to be, "These laws can be significantly different and still produce 'life' of a highly complex nature"

We think that the universe is perfect for life because we are the sort of life that has arisen in this universe, if the laws were different the creatures that existed in a universe holding to those laws would also think "wow, we/it fit(s) the universe/us so well"...

It's not likely that they would say... wow... if only the strong force was half the strength then we'd be made out of much more sensible baryonic matter, rather than these crazy particles (out side of their equivalent of Sci-fi and rampant speculation).

Flamed Diving

Another point. We are assuming that the only life that possibly exists is a self-replicating carbon blob.

Again, I believe this to be myopic and steeped in arrogance.

Fanny Cradock

kiffer wrote: »

The basic answer seems to be, "These laws can be significantly different and still produce 'life' of a highly complex nature"

Sorry, but what does 'significantly different' mean?

kiffer

Fanny Cradock wrote: »

Sorry, but what does 'significantly different' mean?

That's a very good question.
Read the OP again. If the Strong force was stronger then we would have diprotons and dineutrons rather than protons and neutrons because the quarks/hadrons would be more strongly bound together...
This is a significant difference it would make the abundant stable matter of the universe different... but (I think) the strong force could be minutely different and we'd just end up with normal matter but with slightly different half lives for radioactive isotopes, which from a chemistry point of view would be insignificant.


BUT I am not a physicist, I've just been reading alot lately.

robindch

Flamed Diving wrote: »

life as we know it could not exist in 99.9999999999999999999999999% of space.

Doesn't seem all that intelligently designed.

Fanny Cradock

The reason I asked you to clarify what you meant by 'significantly different' is because that term doesn't really tell me anything about measurements. Stronger or weaker by what factor?

My understanding of the fine tuning argument is that it isn't based solely on the strong nuclear force, but on a number of physical constants. I have a feeling that the proposal of this parer hasn't killed the fine tuning argument yet. Still, it will be interesting to see what the fallout from this paper is.

JimiTime

robindch wrote: »

Doesn't seem all that intelligently designed.

And you know about designing universes of course.

Flamed Diving

JimiTime wrote: »

And you know about designing universes of course.

Neither does God, it seems.

JimiTime

Flamed Diving wrote: »

Neither does God, it seems.

Again, you know about designing universes.

Dades

JimiTime wrote: »

And you know about designing universes of course.

I know if I was keeping terrapins I wouldn't build them a giant vacuum tank maintained at -270 degrees Celsius.

JimiTime

Dades wrote: »

I know if I was keeping terrapins I wouldn't build them a giant vacuum tank maintained at -270 degrees Celsius.

Well done, you have shown how you would build a tank for terrapins. Again, you know about designing universes?

Flamed Diving

JimiTime wrote: »

Well done, you have shown how you would build a tank for terrapins. Again, you know about designing universes?

Sure it's in Genesis, right?

You just speak universes into existence.

Simple.

JimiTime

Flamed Diving wrote: »

Sure it's in Genesis, right?

You just speak universes into existence.

Simple.

A designer of universes, and witty to boot.

robindch

JimiTime wrote: »

And you know about designing universes of course.

That's not the point.

If, as a parent I was designing a garden for my kids, I wouldn't (a) make it inconceivably large, (b) make it impossible to visit most of it (c) make all but the tiniest section of it dangerously uninhabitable (d) give my kids the ability to render what little bit is habitable, entirely uninhabitable.

That's simply not very intelligent.

JimiTime

robindch wrote: »

That's not the point.

If, as a parent I was designing a garden for my kids, I wouldn't (a) make it inconceivably large, (b) make all but the tiniest section of it dangerously uninhabitable (c) give my kids the ability to render what little bit is habitable, entirely uninhabitable.

That's simply not very intelligent.

Again, this is based on your experience of creating universes? Anyway, I wont derail yee anymore oh great critics of universe design.

marco_polo

Fanny Cradock wrote: »

The reason I asked you to clarify what you meant by 'significantly different' is because that term doesn't really tell me anything about measurements. Stronger or weaker by what factor?

My understanding of the fine tuning argument is that it isn't based solely on the strong nuclear force, but on a number of physical constants. I have a feeling that the proposal of this parer hasn't killed the fine tuning argument yet. Still, it will be interesting to see what the fallout from this paper is.

The basic argument is that our universe critically depends on a coincidence of properties, and that such coincidence is only possible by supernatural design.

Here is an interesting argument against the The Fine-Tuning Principle by atheist Theodore M. Drange.

The way he formulates the general structure of the Fine-Tuning argument makes it look very weak indeed:

(P1) The combination of physical constants that we observe in our universe is the only one capable of sustaining life as we know it.

(P2) Other combinations of physical constants are conceivable.

(C3) Therefore, some explanation is needed why our actual combination of physical constants exists rather than a different one.

(P4) The very best explanation of the given fact is that our universe, with the particular combination of physical constants that it has, was created out of nothing by a single being who is omnipotent, omniscient, all-loving, eternal, and interested in sentient organic systems, and that he "fine-tuned" those constants in a way which would lead to the evolution of such systems.

(P5) But such a being as described in (P4) is what people mean by "God."

(C6) Hence [from (P4) & (P5)], there is good evidence that God exists.

http://www.infidels.org/library/modern/theodore_drange/tuning.html

marco_polo

JimiTime wrote: »

And you know about designing universes of course.

How could anyone know about something that has never ever been done before?

robindch

JimiTime wrote: »

Again, this is based on your experience of creating universes?

Um, no. It's based upon my experience of what religious people tell me about their deity (or deities) and how little relation there is between what they say, and what the universe is.

The disconnect is with the religious peoples' words, not the universe.

Flamed Diving

JimiTime wrote: »

A designer of universes, and witty to boot.

If it's good enough for goat-herders, it's good enough for me.

jhegarty

I was always under the impression that even a tiny (0.01%) change in the strong force would not only stop life as we know it , but also prevent stars and planets forming.

JimiTime

marco_polo wrote: »

How could anyone know about something that has never ever been done before?

I agree, no-one on this earth of ours has ever created a universe. Yet some seem to feel they are in a position to judge. Go figure.

CerebralCortex

JimiTime wrote: »

I agree, no-one on this earth of ours has ever created a universe. Yet some seem to feel they are in a position to judge. Go figure.

From what we know about the universe are we not in a position to judge it as a place we live in? Besides who said anything about the universe being designed it quite clearly wasn't.

Zombrex

Fanny Cradock wrote: »

You have made the same point before, I believe. The fine tuning argument was never about the proportion of the universe that may or may not be habitable to life as we know it. Rather, it is about the very fundamental physical constants that make life, the universe and everything possible in the first place.

Yes but pointing out the huge proportion of the universe that is utterly devoid of environments necessary for our form of life (or simply normal matter) shows how silly the "fine tuned for life" argument is.

Areas that can sustain life are quite rare in the universe, so what suggests that the universe is designed for these rare bits to exist is some what counter intuitive.

If an intelligence was setting out to design a universe for carbon based life forms to inhabit the idea that this would be the result is just crazy. It is like suggesting designing a dog house for your dog and deciding to arbitraryly make it the size of the Milkyway. What purpose would that serve?

There are far more common things in the universe (stars for example) so why do we not say that the purpose of the universe is to allow these to form. Because obviously the idea that the universe is fine tuned not for life but for nuclear fission doesn't feed into our need to find purpose in our existence.

It is really only the egotistical nature of humans that makes us think that the universe must be fine tuned for us simply because we exist in it. It is our need to feel we exist for a reason that produces these arguments, not any serious argument that the universe actually was designed to produce us.

While the remake of the Day The Earth Stood Still was pretty bad there is one good bit where the Defence Sectary says to the alien "Why have you come to our planet?" and the alien (brilliantly casted as Keanu Reeves) says "Your planet?"

We have a natural tendency to think that where ever we are that this place is there for us.

Fanny Cradock

OK, the word 'designed' inherently carries the presupposition that there is an intelligence behind it. I don't see why we need to stick 'intelligently' in front of it. I think that it can be easily confused with ID.

robindch wrote: »

That's not the point.

If, as a parent I was designing a garden for my kids, I wouldn't (a) make it inconceivably large, (b) make it impossible to visit most of it (c) make all but the tiniest section of it dangerously uninhabitable (d) give my kids the ability to render what little bit is habitable, entirely uninhabitable.

That's simply not very intelligent.

a) Who said the universe was for man and man alone?
b) What about it? The earth has proved to be large enough to hold 6 billion of us, and even now there are places and habitats that remain unfettered from our influence.
c) Pretty much they same point as b. If vast swathes of the universe are uninhabitable, then why complain about not being able to visit them? I'm quite happy not to hop in a spaceship destined for the sun.
d) It sounds like you would prefer to hermetically seal the the garden in plastic, form a defensive perimeter and tether the children at a safe distance from your creation? I had a neighbour like you once. Never saw my footballs or Frisbees again

JimiTime

robindch wrote: »

Um, no. It's based upon my experience of what religious people tell me about their deity (or deities) and how little relation there is between what they say, and what the universe is.

The disconnect is with the religious peoples' words, not the universe.

Your line about the universe has absolutely nothing to do with any religious notion. It was an assertion by you as to knowledge you hold in relation to our universe. I.E. If its designed, its poorly designed. Mere rhetoric and presumtuousness.

Zombrex

JimiTime wrote: »

Again, this is based on your experience of creating universes? Anyway, I wont derail yee anymore oh great critics of universe design.

I've designed a universe (I'm not joking)

Caoimhín

I would content that it is perfectly tuned for life, otherwise the observation could not be made in the first place.

What do alchemists know anyway,.

marco_polo

JimiTime wrote: »

I agree, no-one on this earth of ours has ever created a universe. Yet some seem to feel they are in a position to judge. Go figure.

It seems a more reasonable position than those who believe that only one universe could ever be right for Goldilocks.

Zombrex

Fanny Cradock wrote: »

OK, the word 'designed' inherently carries the presupposition that there is an intelligence behind it. I don't see why we need to stick 'intelligently' in front of it. I think that it can be easily confused with ID.

Traditionally that is done because Darwinian evolution can be thought of as a process of design, albeit unguided and non-directional.

Caoimhín

Fanny Cradock wrote: »

I had a neighbour like you once. Never saw my footballs or Frisbees again

Neighbouring gardens?

What are you proposing my good fellow?

kiffer

Fanny Cradock wrote: »

The reason I asked you to clarify what you meant by 'significantly different' is because that term doesn't really tell me anything about measurements. Stronger or weaker by what factor?

hum... I'm going to be cheap here and say... what ever factor it takes to make a significant difference in the behaviour of matter... :-D

The idea is that apparently you could make noticeable changes to several constants before life as we know becomes impossible, and even after life as we know it become impossible other forms of life can be possible and they too would still ask the same questions.

My understanding of the fine tuning argument is that it isn't based solely on the strong nuclear force, but on a number of physical constants. I have a feeling that the proposal of this parer hasn't killed the fine tuning argument yet. Still, it will be interesting to see what the fallout from this paper is.

Yes... the fine tuning arguement is based on a several things, and not just the Strong interaction... but it's been shown elsewhere that a universe with out the Weak force could still be functional although I imagine that it takes some balancing act with the other forces...

Look.
I'm not saying that all combinations of constants produce universes in which life can exist... I'm just saying that the range that these constants need to be with in is not all that narrow, and even significant changes that produce noticeably different universes in which our sort of life is impossible (or at least very unlikely) does not mean that life suitable for that universe will not arise and ask the same questions that we do... and wonder at how amazing it is that if photons didn't have mass(*) then 'life' would be impossible because the Coulumb force would then have an infinite range and their God would never allow that! (please substitute slightly more sensible changes than giving light mass, such as no weak force, stronger or weaker Strong force, fine structure constant)


(*) photons don't have mass and the Coulumb force does have infinite range in our universes set of rules.



We live in this universe so we think it's normal...

marco_polo

jhegarty wrote: »

I was always under the impression that even a tiny (0.01%) change in the strong force would not only stop life as we know it , but also prevent stars and planets forming.

It is believed that Stars can form in a quite wide number of possible universe configurations.

http://www.newscientist.com/article/mg19926673.900-is-our-universe-finetuned-for-life.html

http://sciencenews.org/view/generic/id/35363/title/Stars_ablaze_in_other_skies

Fanny Cradock

Wicknight wrote: »

Yes but pointing out the huge proportion of the universe that is utterly devoid of environments necessary for our form of life (or simply normal matter) shows how silly the "fine tuned for life" argument is.

Not necessarily. The hope of the Christian (I won't say all Christians) with regards to the afterlife is that there will be a life after life after death (think about it) here on a new type earth. For the Christian who subscribes to this (which is the culmination of God's creation project), the notion that the universe is now complete doesn't fit.

Fanny Cradock

Caoimhín wrote: »

Neighbouring gardens?

What are you proposing my good fellow?

Nothing, old bean. But if you are alluding the multiverse hypothesis then allude away.

Zombrex

Fanny Cradock wrote: »

Not necessarily. The hope of the Christian (I won't say all Christians) with regards to the afterlife is that there will be a life after life after death (think about it) here on a new type earth. For the Christian who subscribes to this (which is the culmination of God's creation project), the notion that the universe is now complete doesn't fit.

What does that have to do with anything?

The argument of the fine tuned universe is that the universe is supposed to look like its is fine tuned for life. If you have to introduce religious faith in order to actually believe this when that is a whole different issue.

Fanny Cradock

Because Christians (some of us) don't believe that the universe is complete. That regions of it are currently uninhabitable is therefore beside the point. Understand?

robindch

Fanny Cradock wrote: »

OK, the word 'designed' inherently carries the presupposition that there is an intelligence behind it.

Not really. Most biologists refer to design in nature very explicitly without the imputation that there's one or more intelligences driving the process.

In general terms, the inference of intelligence is a cognitive error that a lot of religious people seem to make -- that nothing can happen without a conscious entity making it happen intentionally. However, that's beside the point.

Fanny Cradock wrote: »

a) Who said the universe was for man and man alone?

A lot of religious people seem to think it was made for humanity alone (that "dominion" bit in Genesis, for example is usually used to justify this position).

Fanny Cradock wrote: »

b) What about it? The earth has proved to be large enough to hold 6 billion of us, and even now there are places and habitats that remain unfettered from our influence.

Well, other than beneath the earth's surface, I can't think of anywhere that's unaffected by human activity.

Fanny Cradock wrote: »

c) Pretty much they same point as b. If vast swathes of the universe are uninhabitable, then why complain about not being able to visit them? I'm quite happy not to hop in a spaceship destined for the sun.

Yes, but I'm thinking of the 9.99999 (etc)% of the universe that is simply too far away that it could ever be visited, not to mention the 99.99999 (etc)% that can never be visited since it's receding too fast.

Fanny Cradock wrote: »

d) It sounds like you would prefer to hermetically seal the the garden in plastic, form a defensive perimeter and tether the children at a safe distance from your creation?

Er, no. All I'm saying is that if I was a deity designing a place for my irresponsible little playthings, then I'd make it safe and enjoyable. Anything else is just silly.

Fanny Cradock wrote: »

I had a neighbour like you once.

I don't think you've ever had a neighbour like me :P

kiffer

I've just realised that I'm mixing up the Strong Nuclear Force with Strong interaction...
oops...

Zombrex

Fanny Cradock wrote: »

Because Christians (some of us) don't believe that the universe is complete. That regions of it are currently uninhabitable is therefore beside the point. Understand?

No?

What does that have to do with the argument that the universe looks fine tuned for life?

Are you saying that it does if you are a Christian who believes the universe is incomplete?

Are surely that simply means that the universe doesn't look fine tuned without adding this assumption into the mix?

robindch

JimiTime wrote: »

If its designed, its poorly designed. Mere rhetoric and presumtuousness.

Er, it's you guys that are saying that the universe was designed for humanity.

Can't think of anything more amazingly presumptuous than that!

Fanny Cradock

robindch wrote: »

A lot of religious people seem to think it was made for humanity alone (that "dominion" bit in Genesis, for example is usually used to justify this position).

Well, we can better discuss biblical quotes on the other side. However, the verse in question, I gather, is Gen 1:28. Not a whole lot about the universe there.

Then God blessed them, and God said to them, “Be fruitful and multiply; fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth.”

robindch wrote: »

Well, other than beneath the earth's surface, I can't think of anywhere that's unaffected by human activity.

I didn't say 'unaffected' though. Perhaps I should have included 'relatively' somewhere in my initial post, but I believe that my point stands. The Earth has proved to be more than sufficient for our needs as a species. Whether it will remain as such in perpetuity is probably a tangent too far for this debate.

robindch wrote: »

Yes, but I'm thinking of the 9.99999 (etc)% of the universe that is simply too far away that it could ever be visited, not to mention the 99.99999 (etc)% that can never be visited since it's receding too fast.

And what about the rest of the universe? Assuming for a moment there is a God, do you suppose he should have made all the universe accessible to us? I don't assume the universe was made solely for our roadside picnic.

robindch wrote: »

Er, no. All I'm saying is that if I was a deity designing a place for my irresponsible little playthings, then I'd make it safe and enjoyable. Anything else is just silly.

Well that is good for you. And I would respectfully suggest that you and God share the same goal.

robindch wrote: »

I don't think you've ever had a neighbour like me :P

Oh dear!