A Conversation for SEx - Science Explained

A Fine Tuned Universe?

Post 1

U14993989

What is meant by a fine tuned universe and do we live in one?


A Fine Tuned Universe?

Post 2

paulh, vaccinated against the Omigod Variant

This is covered in the book "Lucky Planet," by David Waltham, who evaluates the different properties of Earth and the solar system, which have allowed life to evolve here over approximately four billion years. The book also considers the likelihood that other planets have also had conditions favorable to life, over periods long enough for advanced lifeforms to develop. Stars much bigger than our Sun would likely have gone supernova, exploding and incinerating life [if any] before it could evolve very far. Stars much smaller than our Sun have much longer useful lives, but planets would have to be fairly close to them in order to get much light, and that proximity would place them in danger from periodic solar flares.

Moons can be favorable or unfavorable. There is something called resonance with other nearby bodies, which can disrupt a planet's rotation.

If there's too much carbon, the planet can have a runaway greenhouse effect. If there's not enough carbon, lifeforms might not be able to evolve.

Can life itself regulate a planet's climate, stabilizing it? The jury's still out on that [and might always be out], but from what we can see so far, it's possible.


A Fine Tuned Universe?

Post 3

h2g2 auto-messages

Editorial Note: This conversation has been moved from 'Ask h2g2' to 'SEx - Science Explained'.


A Fine Tuned Universe?

Post 4

Baron Grim

I think it's worth mentioning DNA's ( U42 ) comment on this subject.

“This is rather as if you imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in — an interesting hole I find myself in — fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!' This is such a powerful idea that as the sun rises in the sky and the air heats up and as, gradually, the puddle gets smaller and smaller, frantically hanging on to the notion that everything's going to be alright, because this world was meant to have him in it, was built to have him in it; so the moment he disappears catches him rather by surprise. I think this may be something we need to be on the watch out for.”


A Fine Tuned Universe?

Post 5

paulh, vaccinated against the Omigod Variant

Interesting argument, say I as I listen to raindrops patter on the roof.


A Fine Tuned Universe?

Post 6

2legs - Hey, babe, take a walk on the wild side...

This idea also works on a more smaller scale.... the energys and conformations of atoms, and their subparticular constituation.....

NOt any kind of evidence of some overpowering, force behidn creating it in the ideal way; with infinate, universes, and time, it was bound to occur eventually; plus the fundimental way in which physics dictates things will eventually take on a given form, due to the very basic propertys of force, mass, gravity, electromagnetic attraction etc., etc., etc., - a random pile of bricks is more likely to take on the more stable strcture as such external forces work on it, like gravity... - or, 'sometimes it all comes together' smiley - zensmiley - 2cents


A Fine Tuned Universe?

Post 7

paulh, vaccinated against the Omigod Variant

If you have trillions of stars and planets, there might well be millions of planets where life can and does develop. The catch is that they will likely be separated by vast distances that make intercommunication unlikely at best. This may also be fortunate in a way. Who knows if they would be friendly [or if we would be friendly toward them] if communication was possible.

It's possible that there many different universes, and that some are more likely to be friendly to life than others. Again, we aren't even close to being able to prove that one way or the other.

But assuming that there are many different universes, is it possible that the one we are in is more or less life-friendly than the others?


A Fine Tuned Universe?

Post 8

U14993989

Hi thank you for your responses.

I was referring to a fine tuned universe rather than a "fine tuned planet". I assume the puddle DNA was referring to was an analogy for the planet earth - rather than the whole universe?


A Fine Tuned Universe?

Post 9

paulh, vaccinated against the Omigod Variant

That's fine, Stone Aart, except that we have only one example to use as a reference point for life-friendly universes or parts thereof.

Wikipedia defines fine-tuned universe as : "The fine-tuned Universe is the proposition that the conditions that allow life in the Universe can only occur when certain universal fundamental physical constants lie within a very narrow range, so that if any of several fundamental constants were only slightly different, the Universe would be unlikely to be conducive to the establishment and development of matter, astronomical structures, elemental diversity, or life as it is understood."

Now, I grant that Wikipedia may or may not be accurate in framing the matter that way. Many scientists are careful not to assume that carbon-based lifeforms are the only type of lifeforms that can exist. At the end of the day, though, that's our frame of reference until non-carbon-based lifeforms can be detected somewhere, anywhere.

If oxygen and hydrogen had different properties, they might not be able to come together as water in the ways that are familiar to us. If carbon had different properties, who knows what effect that would have on its ability to combine with other elements [which would likely be different as well].

So, we sit in our puddle wondering if the rain that fell on us was a one-shot shower incapable of being repeated, or will recur again, not just here but elsewhere.


A Fine Tuned Universe?

Post 10

tucuxii

>> I assume the puddle DNA was referring to was an analogy for the planet earth - rather than the whole universe?<<

Given the universe is finite - rather than merely an analogue of what we can perceive and describe - then the puddle analogy is valid for life on earth and the "whole universe"


A Fine Tuned Universe?

Post 11

U14993989

>> puddle analogy is valid for life on earth and the "whole universe" <<

Then the sun in DNA's analogy must lie outside the universe.


A Fine Tuned Universe?

Post 12

Baron Grim

Not at all. The metaphor is about the egocentricity of humans to believe that our environment was adapted to fit us and not that we adapted to fit our environment. We only have experience of this universe and this solar system and this planet with its one large moon and radiation blocking magnetic field. If this universe had slightly different properties we wouldn't be here, but we can't know that no life could be here. We haven't found an environment on Earth yet, no matter how extreme that doesn't harbor some form of life so we know that even within the wide range of conditions here, life can greatly adapt. Given different physical rules in an less "finely" tuned universe we can't really say that some sort of "life" couldn't exist. It could be something as exotic as a pure energy intelligence. We can't even imagine what could happen with the slightest differences in physics, but I feel it's awfully conceited to think something wouldn't adapt somewhere.

However...

There have been similar discussions before. I remember the arguments that ran amongst scientist before we knew whether the universe was ever expanding or if it would collapse at some future point or whether it would find a point of stability. The thought at the time was that very small differences at the point of the big bang could have meant that the universe would have collapsed within a small fraction of a nanosecond or it could have expanded so quickly that it would become too diffuse and cold for anything like stars and planets to form.

So, yes. In some ways it is a finely tuned universe in the sense that it exists at all.


I believe we really can't know a definitive answer to this question. The way it's stated, in the passive voice suggests an unstated "tuner" or creator. And so I remain agnostic. I don't think we can know the answer, but it is a fun question to ask.


A Fine Tuned Universe?

Post 13

paulh, vaccinated against the Omigod Variant

"I believe we really can't know a definitive answer to this question. " [Baron Grim]

I agree.

" I don't think we can know the answer, but it is a fun question to ask" [ditto]

"The thought at the time was that very small differences at the point of the big bang could have meant that the universe would have collapsed within a small fraction of a nanosecond or it could have expanded so quickly that it would become too diffuse and cold for anything like stars and planets to form."

A very recent proof of the propulsive qualities of gravity in the first few microseconds of the Big Bang has shed some light on this. It was in the Sunday Boston Globe a few weeks ago, but I'm not qualified to even describe it, let alone explain it.


A Fine Tuned Universe?

Post 14

2legs - Hey, babe, take a walk on the wild side...

Interesting... or perhaps not... smiley - headhurtssmiley - doh to think of the question the other way round..... and then the answer is clear.....

sort of... and its too hot to think properly here today smiley - laugh sort of....

Of course we do live in a finely tuned, almost perfect, almost too perfect for life, seming universe; if it were not, we would not, as we would not be here... therefore its 100% inevitable that any lifeforms, kinda like us, would end up in such a universe, as such a universe is necessary for such to exist.... ; We don't get to glimpse all the failed versions en-route, or post now, as they, thereby, clearly don't have the necessary to support such life... smiley - ermsmiley - sorry too hot to explain that... err... I know what I mean... honest... smiley - laugh


A Fine Tuned Universe?

Post 15

paulh, vaccinated against the Omigod Variant

here's a link to the Boston Globe article I mentioned:

http://www.bostonglobe.com/magazine/2014/05/02/alan-guth-what-made-big-bang-bang/RmI4s9yCI56jKF6ddMiF4L/igraphic.html


A Fine Tuned Universe?

Post 16

ITIWBS

One of my favorite illustrations of the fine tunning concept has to do with the decay characteristics of Americium and its microelectronic properties, its first decay being by means of emission of a beta particle, a high energy electron, making it suitable for printing directly into integrated microcircuits to provide electrical power, as it was used for example in the first generation of digital watches.

The first decay is followed by a second decay involving emission of an alpha particle, or helium nucleus, leaving one finally with a nonradioactive residue.

It couldn't have been much better designed as power media for microelectronics consonant with safety if had been done on purpose,
Arguing that fine-tuning


A Fine Tuned Universe?

Post 17

ITIWBS

has as its object eventual development of machine intelligence.


A Fine Tuned Universe?

Post 18

paulh, vaccinated against the Omigod Variant

Do they still use it for that purpose, or has something else superseded it?


A Fine Tuned Universe?

Post 19

ITIWBS

The price has gone up and digital watches are usually battery ops these days.


A Fine Tuned Universe?

Post 20

paulh, vaccinated against the Omigod Variant

I expected some such thing....


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