A question or proposition as to why we are not alone

[jjjnettie (Jeanette)]

Originally Posted by bojan

, but that's how science works...

yep, yep, yep, we need evidence before we can say for certain that there is life elsewhere in the Universe.
Even though in our hearts we know there is.

[bojan]

Originally Posted by jjjnettie

Even though in our hearts we know there is.

Quite so

[The_bluester (Paul)]

My own perspective is, given the current estimates of what proportion of stars are likely to have planets, and what proportion of panets are likely to provide conditions suitable for live as we can conceive of it (I think it would be a mistake to only consider "earthlike" planets as candidates for life) and given how many galaxies have been observed by the likes of the Hubble scope. I think it is almost inconceivable that this is the only place in the universe where life has come about. Will we ever have undeniable proof that Earth is the only place where ther is life? I doubt it. Will we ever prove that there is no other life in the universe? No, that is a position that could only ever be disproved, not proven!

[Rob_K]

I acknowledge your points Bojan, but it is not speculation. Speculation would be talking about some theoretically-modelled occurrence for which there was no empirical data. In this case, we have empirical data (Earth) as well as a rough (though evolving) model of how life formed. It is extrapolation of course.

We started off billions of years ago with a rich cloud of dust and gas, applied the universal laws of physics, and ended up with abundant life. Indisputable, nothing else, no magic. Because life beyond the Solar System may prove difficult (or even impossible) to detect at least in the short term, in considering the possibility of life elsewhere in the Universe we look to other systems. That is, looking for things that might make our Solar System unique. Not so many years ago the existence of extrasolar planets was speculation. Then improving technology found big ones. More improvements in resolution - smaller and smaller ones. We're still working on resolution, but are down to super-Earths now. Planetary systems are abundant. And that's just close to us in the Milky Way. Talk to planetary scientists and tell them that Earth-sized bodies are pure speculation until proven by hard empirical data!

If you want hard proof before considering the possibility of life elsewhere in the Universe, you may have a long wait. Mars would be great, but really we know already that conditions were right in our Solar System for the emergence of life. I disagree with your view of the way science works - if it was just the interpretation of empirical data, it would not advance.

Cheers -

[CraigS]

Originally Posted by Rob_K

The universal laws of physics applied to planet formation produce life.
..
And we have empirical evidence of the building blocks of life in far flung objects such as comets.

When we spectroscopically detect an exotic new compound in a distant star system, do we say, well that is the only place in the Universe that this compound exists, until we get indisputable empirical data to say otherwise?

To the best of my knowledge, no one has ever reproduced life from its fundamental constituents.
This suggests that there are some missing elements in our understanding of how it gets started
What are those elements ? Where do they exist ? Under what physical conditions do they come together to form life ? Where in the universe might they be found ? How many of these places exist ?

The gaps in our understanding of life are huge .. perhaps commensurate in size and number, as the dimensions of the universe. If this is not so, then why is it not so ?

The laws of Physics govern what happens when a brick on a rubber band is pulled up an inclined plane of carborundum paper. No matter how many times you run the experiment every outcome is different. It is called a complex system. (Credit to: Bert).

Does life happen this way ? If not, why not ? Are the number of attempts related to chance duplicate outcome ? If so, how many attempts are needed? If not, then is it reasonable to agree with an empirical, observationally demonstrable model, that every outcome is different, no matter how many times you run the experiment ?

Originally Posted by Rob_K

The burden of proof is on the naysayers to find evidence that life is magical after all, or that the Solar System (or Earth) is somehow unique in all the Universe, or that the universal laws that produce life apply to only our small corner of the Universe. The proof required would be extraordinary because we already have the empirical evidence. Fence-sitters... well they're in denial both ways.

Why is it so important to be right about such a nonsense issue ?
There's something else afoot here, methinks !

Originally Posted by Rob_K

In practical terms we may never detect life outside our own Solar System (or detect it to the satisfaction of everyone!), but we can be pretty certain it exists. We are the proof.

Last time I looked, we live inside the Solar System.

Cheers

[bojan]

Originally Posted by Rob_K

... It is extrapolation of course.

Exactly as you said... extrapolation.

Please don't get me wrong, I do want this extrapolation to be proven correct one day.. but at this stage, it is only extrapolation, based on only one single data point. That is my point.

Originally Posted by Rob_K

We started off billions of years ago with a rich cloud of dust and gas, applied the universal laws of physics, and ended up with abundant life. Indisputable, nothing else, no magic.

I fully agree with this.

Originally Posted by Rob_K

Planetary systems are abundant. And that's just close to us in the Milky Way.

That has been proven on 150+ examples so far, so with this statement I have no problems.

Originally Posted by Rob_K

If you want hard proof before considering the possibility of life elsewhere in the Universe, you may have a long wait. Mars would be great...

Yes, I do want hard proof.. I bet you do as well
I agree, waiting is hard, though

[GrampianStars (Rob)]

Originally Posted by Rob_K

Interesting read. To me it seems simple........
In practical terms we may never detect life outside our own Solar System (or detect it to the satisfaction of everyone!), but we can be pretty certain it exists. We are the proof....

Mmmmmm.............. doesn't wash
What you are also assuming that by association the universe is awash with Ipods, WMD's, Internet, WAR, fuel guzzling machines, etc......
as We Have the proof

[Rob_K]

Originally Posted by CraigS

To the best of my knowledge, no one has ever reproduced life from its fundamental constituents.
This suggests that there are some missing elements in our understanding of how it gets started
What are those elements ? Where do they exist ? Under what physical conditions do they come together to form life ? Where in the universe might they be found ? How many of these places exist ?

Yes, very valid questions although pretty obvious ones Craig. But the fact is it did get started. Dust & gas + universal laws of physics = life, in this solar system. That is the simple statement of input and output.

Originally Posted by CraigS

The gaps in our understanding of life are huge .. perhaps commensurate in size and number, as the dimensions of the universe.

Pure speculation. If they are gaps, how can they be measured?

Originally Posted by CraigS

The laws of Physics govern what happens when a brick on a rubber band is pulled up an inclined plane of carborundum paper. No matter how many times you run the experiment every outcome is different. It is called a complex system. (Credit to: Bert).

Does life happen this way ? If not, why not ? Are the number of attempts related to chance duplicate outcome ? If so, how many attempts are needed? If not, then is it reasonable to agree with an empirical, observationally demonstrable model, that every outcome is different, no matter how many times you run the experiment ?

Dear oh dear, so many ifs and if nots. Are you trying to say it's all too difficult, so don't bother? If we don't know what started life, how can you speculate on what sort of system it is? I could posit that the actual beginnings of life are a simple system that must occur, with equal validity. But of course I wouldn't.

Originally Posted by CraigS

Why is it so important to be right about such a nonsense issue ?
There's something else afoot here, methinks !

LOL, it's called paranoia!

Originally Posted by CraigS

Last time I looked, we live inside the Solar System.

Cheers

No, we live in a solar system.

Cheers -

[supernova1965 (Warren)]

Originally Posted by CraigS

To the best of my knowledge, no one has ever reproduced life from its fundamental constituents.
This suggests that there are some missing elements in our understanding of how it gets started
What are those elements ? Where do they exist ? Under what physical conditions do they come together to form life ? Where in the universe might they be found ? How many of these places exist ?

The gaps in our understanding of life are huge .. perhaps commensurate in size and number, as the dimensions of the universe. If this is not so, then why is it not so ?

The laws of Physics govern what happens when a brick on a rubber band is pulled up an inclined plane of carborundum paper. No matter how many times you run the experiment every outcome is different. It is called a complex system. (Credit to: Bert).

Does life happen this way ? If not, why not ? Are the number of attempts related to chance duplicate outcome ? If so, how many attempts are needed? If not, then is it reasonable to agree with an empirical, observationally demonstrable model, that every outcome is different, no matter how many times you run the experiment ?



Why is it so important to be right about such a nonsense issue ?
There's something else afoot here, methinks !


Last time I looked, we live inside the Solar System.

Cheers

Actually some one did just that and found organic compounds and amino acids in the flask. Link Here

[joe_smith]

We started off billions of years ago with a rich cloud of dust and gas, applied the universal laws of physics, and ended up with abundant life. Indisputable, nothing else, no magic.

Hi Rob but if life is that simple where is the evidence for it being this simple? We have a theory on how life evolves but not the actual cause of that life here. We have no idea how life started here or even how our consciousness fully works for Intelligent life. As far as I can tell there is not one laws of physics that deals with how life started. How dose a cloud of lifeless dust and gas turn into a fully conscious Intelligent life-form? For me the odds for life starting here on earth and to have the life forms we have here to day all working in harmony in nature happening again on another planet is unreal to me. Its like throwing a million playing cards out of a plane and watching them hit the ground and then doing it again and all the cards line up on one another. For me life was formed with he univese or life was the goal and not just a by-product, because so far all the evidence on earth shows life can only come from life. Why hasn't a Stanley Miller's famous spark type of experiments formed a living cell? if life was that simple, a simple cell is anything but simple.

[CraigS]

Originally Posted by supernova1965

Actually some one did just that and found organic compounds and amino acids in the flask. Link Here

No life .. keep trying Warren ..
… you are underestimating and oversimplifying, the steps beyond the simple synthesis of complex organic molecules from simpler chemicals, and the emergence of complex molecules capable of life functions.

Cheers

[supernova1965 (Warren)]

Originally Posted by CraigS

No life .. keep trying Warren ..
… you are underestimating and oversimplifying, the steps beyond the simple synthesis of complex organic molecules from simpler chemicals, and the emergence of complex molecules capable of life functions.

Cheers

I didn't once in my post claim he created life but I did show that he created the building blocks of life.

[bojan]

Originally Posted by supernova1965

I didn't once in my post claim he created life but I did show that he created the building blocks of life.

And then you extrapolate...
But this is not proof yet.

Guys, we are talking here about how science works -
Personally, I strongly believe the extraterrestrial life is abundant and just by-product, not a goal.. (Whose goal, BTW ???).
But, this is only MY, personal belief.. and I don't have any proof for it yet.

On the other hand, if/when we find a bacteria in Mars' soil, THAT will be enough proof for me that this can happen on other planets.
With two data points, extrapolation is much more accurate process...

[supernova1965 (Warren)]

Originally Posted by bojan

And then you extrapolate...

Isn't that how we learn stuff to take evidence and then to extrapolate and form a theory and then prove that theory to be fact. If scientists didn't extrapolate we would learn nothing.

[CraigS]

Rob (& Warren);

There is much to learn from keeping an open mind.

You'll find that complex systems biology is a field of mainstream science which investigates the structure and function in biological organisms with emphasis on the emergence of, and subsequent evolution of organisms and species.

It is based on the complex interactions within biological systems. Its key focus is on the mathematical modelling of fundamental relations and patterns, leading to the emergence of life. There is a partial overlap with with complex systems theory and it covers the range of abstract theoretical complex systems within applied mathematics, with or without relevance to biology, chemistry or physics.

It is not speculation that complexity theory is used to model aspects leading to the emergence of life. It is used because the observed characteristics we refer to as the 'template' definitions of life, match the theory. (Eg: Emergence, self-organisation, replication, reproduction, complex symbiotic interactions with local an external environments, etc).

I assure you, there is much more to where I'm coming from, than my irrelevent opinions.

The simple mathematical/statistical models cited in this thread, (and many others on this same topic), are basically irrelevant when compared with where modern theory and modelling has taken us.

We should adapt before making wild statements which are not supportable in the face of such developments, and make statements which are supportable.

I may look like a simple fence-sitter but I assure you, there are many good reasons for not making wild inaccurate statements. At least I am aware of what I don't know .. even if I am not an expert in it.

Cheers

[bojan]

Originally Posted by supernova1965

Isn't that how we learn stuff to take evidence and then to extrapolate and form a theory and then prove that theory to be fact. If scientists didn't extrapolate we would learn nothing.

Extrapolation is fine as a starting point, as a working hypothesis.. driving force ... like "This could be, lets see if it's true.." but is nowhere near proving something to be true.

[supernova1965 (Warren)]

I believe it is a wildly inaccurate statement to say that there isn't more evidence for life than for none. There is a lot more evidence for life than evidence to say that none exists I still haven't seen any evidence showing it doesn't exist. If we were not here discussing this I would agree that the chances are that there was none but then I wouldn't be able to say that would I as I wouldn't be here.

[supernova1965 (Warren)]

Originally Posted by bojan

Extrapolation is fine as a starting point, as a working hypothesis.. driving force ... like "This could be, lets see if it's true.." but is nowhere near proving something to be true.

That is my point but if we took the opposite position we would get nowhere I never said it was proof. But it is a lot closer to saying it does exist than saying it doesn't. I don't think that anyone can honestly say that there isn't more circumstantial evidence for life than circumstantial evidence for it not existing at some stage we have to say the balance is in favour of it being there somewhere while this is not proof it makes it more likely than not. That is my point it is a driving force while the view that it may not exist is a regressive force. Also there is evidence that life didn't start only once on earth but twice. http://richarddawkins.net/discussion...once-but-twice

[joe_smith]

Personally, I strongly believe the extraterrestrial life is abundant and just by-product, not a goal.. (Whose goal, BTW ???).
But, this is only MY, personal belief.. and I don't have any proof for it yet.

This is the whole thing with a chat about the possibility of life on other planets there is no proof at all. All views about the facts we have so for are being interrupted by our own world views (me included) and has been stated here, what we believe in our hearts. As to whose goal, who knows or even if there is a something watching. But until we find the golden nugget of evidence can you rule it out? you can with your current world view of what you believe to be fact, but can you rule it out scientificily using science. To me no, until one is proven and the other is disproven I will keep a open mind. Dont forget the notion of small bugs causing disease was laughed at as being so stupid until Louis Pasteur Proved Germs Cause Disease and started the whole new world of micro biology for me we have only opened the box on the origin and meaning of life and are on a wonderful journey, just dont get stuck on a oneway path its going to be a multiple path maze for the truth. I would like to hear why people hold the view they have, and what facts they use to get to that view.

[TrevorW]

One thing for sure that is certain science fiction has often become science fact regardless of the all the sceptics lets not forget that