Trillions of Earths

[CraigS]

Originally Posted by bojan

Among a lot of creationists crap, I found this:
http://www.youtube.com/watch?v=I14KTshLUkg

I remember couple of articles that discuss this issue.. when I find them again, I will post them here...

Don't bother Bojan … forget about it …

Perhaps poorly considered and articulated thoughts on my part … one of the downsides of taking the position of 'exo-life may, or may not exist', is trying to see it from both sides at the same time .. I'm no creationist, also … so I'm not even going to bother trying to support this line.

I'm outta here … going to concentrate on entanglement instead (ie: the other concurrent thread).


Cheers

[Robh (Rob)]

We deduce that life requires certain conditions e.g. life supporting chemicals and a habitable zone. However, the existence of those chemicals and a habitable zone do not necessarily imply life will originate there.
In reality, we know nothing about the probability of life forming anywhere else in the Universe. We have no confirmed life data from any exo-planet.

Sure there may be 100 billion galaxies, each with 100 billion stars. That's 10^22 stars. So you think that's big!
The smallest known DNA viruses have 32000 base pairs. A single chain of DNA is composed of a sequence of 4 nitrogenous bases. Assuming they all occur in equal amounts i.e. 8000 of each, then the number of possible ordered sequences of a single chain of DNA are 32000!/(8000!)^4. Don't try using your calculator, the value is too large.
32000! ~ 1.07 x 10^130270 and 8000! ~ 5.2 x 10^27752.
32000!/(8000!)^4 ~ 1.5 x 10^19259
That pretty much dwarfs the 10^22 stars in the Universe!!

Before the biologists come looking for blood, I haven't said anything about the probability of the organism forming. However, the chances of life forming may be significantly lower than any estimate we have in mind.

On the other hand, if by fluke an alien neighbour exists and communicates with us, we can at least say we are not unique.

Regards, Rob.

[CraigS]

Thanks for making that statement Rob. (I failed spectacularly !).

But it really is fascinating just comparing the two number scales.

Of this number of possible ordered sequences of a single chain of DNA (ie: huge), one, or some of these, evolved to result in DNA chain(s) we recognise today - here on Earth.
Lots of things must have influenced these chemicals, to result in the arrangements we now see. We still don't really know the magnitudes of the numbers of these influences yet, either.

The probabilities of these influences occurring, (perhaps even in specific time sequences), anywhere, also seems to be mind-blowing.

Fantastic stuff !

I don't know what this means in the context of the current discussion, though.

Somehow the scales must be linked .. and discovering these linkages would be/is awesome. (Some have been discovered but these discoveries seem infinitesimal, compared with what remains to be discovered).

We skim over these thoughts when we read information about the scale of the universe, but the scale of what's going on in our own backyard, is even more mind-blowing !!

Cheers

[bojan]

Originally Posted by CraigS

I don't know what this means in the context of the current discussion, though.

The link is obvious (to me): Fermi paradox is N x bigger than previously thought (because there are N x more stars.. especially dwarfs).

As far as comparing the number of possible permutations within DNA and number of stars.. In my opinion this is like comparing apples and pears.
Current DNA on Earth is result of evolution (it started with much, much simpler molecules, and has grown by adding information by means of mutations and Darwinian selection, and I feel this growth was not linear with time). The number of stars has grown, but under different rules....

However, I should have started separate thread to discuss this.. but I didn't.. because I don't have much time recently so I tried to sneak in.
My apologies for this intrusion
Later when I have more time, I will certainly start again .

[CraigS]

I would love a discussion on/around this topic, Bojan.

Go for it !! You can start it off.

I agree that we're comparing apples and pears but as far as number scales generated by nature, and somehow linked by nature, the numbers themselves can be laid side by side.

The trick is to talk about the right links. Requires a lot of clear thinking, knowledge and discipline.

Great topic.

Good onya .. I'll look forward to that one.

Cheers

[mswhin63 (Malcolm)]

I was thinking this needs another thread too

[avandonk]

Originally Posted by Robh

We deduce that life requires certain conditions e.g. life supporting chemicals and a habitable zone. However, the existence of those chemicals and a habitable zone do not necessarily imply life will originate there.
In reality, we know nothing about the probability of life forming anywhere else in the Universe. We have no confirmed life data from any exo-planet.

Sure there may be 100 billion galaxies, each with 100 billion stars. That's 10^22 stars. So you think that's big!
The smallest known DNA viruses have 32000 base pairs. A single chain of DNA is composed of a sequence of 4 nitrogenous bases. Assuming they all occur in equal amounts i.e. 8000 of each, then the number of possible ordered sequences of a single chain of DNA are 32000!/(8000!)^4. Don't try using your calculator, the value is too large.
32000! ~ 1.07 x 10^130270 and 8000! ~ 5.2 x 10^27752.
32000!/(8000!)^4 ~ 1.5 x 10^19259
That pretty much dwarfs the 10^22 stars in the Universe!!

Before the biologists come looking for blood, I haven't said anything about the probability of the organism forming. However, the chances of life forming may be significantly lower than any estimate we have in mind.

On the other hand, if by fluke an alien neighbour exists and communicates with us, we can at least say we are not unique.

Regards, Rob.

The odds of winning tattslotto are about eight million to one yet it is won every week or most weeks!

Statistics like this are meaningless as most people do not understand statistics.

A glib calculation of the possible arangment of DNA does not add to anything. To then even compare this to the ' known' number of stars is futile.

I am not saying that all speculation should be suppressed. All I am asking is that a reasonable attempt is made to understand the current science.

Every particle that exists in the Universe follows the laws of Physics. The fact we do not totally understand ALL these laws makes no difference to how the Universe behaves.

To just partition the unexplanable to 'gods' is a total cop out. It is just proof of feeble minds looking for simple answers.

It is OUR job to work out how things tick.

Less than a hundred years ago the scientific view was that there was only ONE Galaxy. Quantum Mechanics had just been made mainstream only amongst top scientists.

Yes by all means have a discussion about biology as I happen to know a bit about it. We call it Molecular Biology.

I happen to think that life is inevitable as everywhere we look it is there.

Bert

[CraigS]

Hi Bert;

I was wondering when you'd comment on all this ..

I welcome your expertise on these topics !

What do you mean by your last comment ?...

"I happen to think that life is inevitable as everywhere we look it is there."

This would seem to only refer to Earth.

The main discussion is about life elsewhere.

Cheers

[avandonk]

For quite a while life could only exist with sunlight and plants and animals. Look up terrarium.

Then we found ecosystems living at six or more km deep with only H2S as an energy source. These communities of bacteria and valve worms etc are living at the edges of volcanic vents.

This was my tipping point. I realized we knew nothing of what constituted life.

This latest discovery of bacteria with Arsenic rather than Phosphorus was another fact that nailed it further.

We are just groping our way into the Universe with limited knowledge. If there are self contained ecosystems near volcanic vents then life is everywhere there is liquid water.

I just get angry when people try to prove that life is a god given right by setting up a sham probabilty of how impossible it all is.

It is standard fundie claptrap.

Bert

[CraigS]

Ok .. I accept the bit about fundie stuff. I agree. Lets park that one.

You make the statement: "I realized we knew nothing of what constituted life" and then "Phosphorus was another fact that nailed it further."

This would seem to be at odds with the following statement:

"then life is everywhere there is liquid water".

If we don't understand what constitutes life, then how can we say that it will be everywhere where there is liquid water ? Please note that this question is in the context of the topic at hand … ie:

Does this mean that wherever there is liquid water elsewhere in the Universe, we will find life ?

I'm not having a go at you, I'm just intrigued with where you're coming from on the increased possibility of life existing elsewhere (with extra stars/planets and Phosphorous).

Cheers & Rgds.

[avandonk]

Yes craig all life as we know it needs liquid water. I have no proof life is anywhere else but my argument is far more logical than twits calculating impossible odds for life to exist without a creator. They are trying to prove their uniqueness because of a mythical all knowing all present being. This is total nonsense!
In my humble opinion the Universe is teeming with life. Fortunately they are too far away to hurt us.
The latest bacteria that use arsenic rather than phosphorus shows how ubiquitous life is.
One could contemplate a silicon and germanium rich planet with solid state computer like life. But how do they replicate without a fab?

Bert

[CraigS]

fab ?

[avandonk]

A fab in the trade is the multi billion dollar factory that makes computer chips.

Bert

[CraigS]

Ok .. thanks for that.

Thanks for your views, also. The perspective that were are all composed of molecules obeying the laws of nature, resulting in fractal patterned beings, (and organs), would tend to hint that life now, at least, has some kind of descriptive language.

I've been thinking along these lines lately (since you implanted the idea).

Be interesting to kick that idea around for a while, also.

Unfortunately, I have to run … other things to do.

Catch up with you later .. maybe we need to start our own thread and not wait for Bojan.



Cheers & Rgds

[Robh (Rob)]

Originally Posted by avandonk

A glib calculation of the possible arangment of DNA does not add to anything. To then even compare this to the ' known' number of stars is futile.

I am not saying that all speculation should be suppressed. All I am asking is that a reasonable attempt is made to understand the current science.
....

Yes by all means have a discussion about biology as I happen to know a bit about it. We call it Molecular Biology.

I happen to think that life is inevitable as everywhere we look it is there.

Bert

Hi Bert,

Good to have your input. The calculation of the number of possible base sequences in the DNA actually did have a purpose. The number is extraordinarily large and some would conclude (incorrectly) that the chance the virus exists at all is close to zero. In fact, arguments along this line have been used before by some creationists. However, as Craig correctly remarked, in itself the number tells us nothing about the probability that the virus came into existence. It was meant to counter the argument that the sheer number of stars by themselves imply life is inevitable and widespread. Whether there is a billion stars or 10^22 stars, it tells us no nothing about the frequency of life in the Universe. We can calculate figures for planets in habitable zones but you don't have any statistical evidence for the existence of life forms. As I stated earlier, the existence of suitable chemicals and conditions don't necessarily imply that life exists there.

I don't take the view that life is inevitable or not inevitable in the Universe at large. There is just no statistical evidence to support either view. The Earth may be a unique sample of one.

Regards, Rob

[CraigS]

Originally Posted by Robh

Hi Bert,

Good to have your input. The calculation of the number of possible base sequences in the DNA actually did have a purpose. The number is extraordinarily large and some would conclude (incorrectly) that the chance the virus exists at all is close to zero. In fact, arguments along this line have been used before by some creationists. However, as Craig correctly remarked, in itself the number tells us nothing about the probability that the virus came into existence. It was meant to counter the argument that the sheer number of stars by themselves imply life is inevitable and widespread. Whether there is a billion stars or 10^22 stars, it tells us no nothing about the frequency of life in the Universe. We can calculate figures for planets in habitable zones but you don't have any statistical evidence for the existence of life forms. As I stated earlier, the existence of suitable chemicals and conditions don't necessarily imply that life exists there.

Thanks Rob.

Originally Posted by Robh

I don't take the view that life is inevitable or not inevitable in the Universe at large. There is just no statistical evidence to support either view. The Earth may be a unique sample of one.

The problem here is that whatever processes which brought DNA/RNA, viruses and cells into existence on Earth (from chemical 'soups'), should also operate somewhere else, within the vast sample space.

This thinking then leads to the opinion that the Universe is teeming with life.

But the permutations and combinations of environmental conditions, necessary to support the processes leading to a viable candidate outcome, may actually turn out to be of more significance and impact on a single successful outcome, than the mere presence of the right compounds (eg: water), and processes, which have operated here on Earth.

We presently pay very little attention to these aspects. Once again, we have little/no empirical evidence underpinning these considerations, outside of the terrarium called Earth.

How big does our observation window on the fractal have to be before we can perceive, (and empirically, verify), self-similarity ?

Cheers

[CraigS]

The thinking in my last post reminds me of the analogy used to describe extra dimensions in M-theory.

The ant on the telephone wire. No problem for the ant to see the spiral pattern of the wire … big problem for a human 50 metres away to see it, though.

The recognition of the pattern of life existing elsewhere also depends on our own perception of the pattern. The ant at 50 metres, would have great difficulty in recognising humans, as life forms.

The point about this perspective is that our perception of what may constitute life has just changed to include phosphorous [EDIT: oops .. should read Arsenic] based DNA/RNA. Just what level of significance does this really have, (empirically), in the scale of permutations of possible DNA/RNA bases ? Does it really have an impact on the frequency of viable outcomes ?

Cheers

[bojan]

Originally Posted by CraigS

The point about this perspective is that our perception of what may constitute life has just changed to include phosphorous based DNA/RNA.

You meant arsenic ,of course

[CraigS]

Originally Posted by bojan

You meant arsenic ,of course

oops .. Edits made to original post ..
… but what are your comments on the line of thinking, Bojan ?

Cheers

[bojan]

Originally Posted by CraigS

oops .. Edits made to original post ..
… but what are your comments on the line of thinking, Bojan ?

Cheers

Your line of thinking (and Bert's) is more or less the same as mine
However, to satisfy the scientific processes and procedures (excuse me for this "managerial talk") we have to go on searching for evidence, direct and indirect., of course.