John Gribbin has just had a new book reviewed in the New Scientist journal.
Full title : Alone in the universe : Why our planet is unique.

I have not yet been able to get hold of this book, though I would like to.
According to the review, it argues that Earth is essentially unique - the result of a series of lucky 'accidents' or coincidences, that makes it suitable for life, while the odds against intelligence developing elsewhere is slim.

Some of these 'coincidences' are :

The Solar system formed at the right time, and in the right place to have the full set of metals and elements required for life.
Further from galactic centre, and those elements would not be available. Closer in, and life would likely be wiped out by a gamma ray burster or nova. Or even get too close to our galaxy's supermassive black hole.
Our solar system is unusual in having stable orbits.
Earth is exactly the right distance for liquid water
Asteroids which might bombard the planet are safely tucked away in the asteroid belt or Kuiper Belt.
Yet Earth received exactly the right type and number of collisions early in its history to provide water.

And lots more similar arguments.

What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

Lance wrote:John Gribbin has just had a new book reviewed in the New Scientist journal.
Full title : Alone in the universe : Why our planet is unique.

I have not yet been able to get hold of this book, though I would like to.
According to the review, it argues that Earth is essentially unique - the result of a series of lucky 'accidents' or coincidences, that makes it suitable for life, while the odds against intelligence developing elsewhere is slim.

Some of these 'coincidences' are :

The Solar system formed at the right time, and in the right place to have the full set of metals and elements required for life.

+/- a few billion years.

Further from galactic centre, and those elements would not be available.

Simply false. There's plenty of metals in the outer spiral arms.

Closer in, and life would likely be wiped out by a gamma ray burster or nova. Or even get too close to our galaxy's supermassive black hole.

Being right in the core might be an issue but the core is not a great proportion of the volume of the galaxy.

Our solar system is unusual in having stable orbits.

False.

Earth is exactly the right distance for liquid water

Give or take a few million miles. The zone of liquid surface water gradually moves outwards as the Sun ages but much depends on the planetary atmosphere.

Asteroids which might bombard the planet are safely tucked away in the asteroid belt or Kuiper Belt.

That is simply because the ones that weren't "tucked away" already collided with the planets and other bodies. cf late heavy bombardment. Ie such stuff is rapidly cleared.

Yet Earth received exactly the right type and number of collisions early in its history to provide water.

Mars also had lots of water but lost most of it due to lack of mass and magnetic field. Accumulation of water is more the rule than the exception.

And lots more similar arguments.

What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

A load of bunk if the above arguments are all he's got.

Lance wrote:
According to the review, it argues that Earth is essentially unique - the result of a series of lucky 'accidents' or coincidences, that makes it suitable for life, while the odds against intelligence developing elsewhere is slim.

I'm always skeptical of such claims, just like I'm always skeptical whenever I hear someone claim that the universe is teeming with life. I think we just don't know enough about the universe yet to make a good argument either way.

Lance wrote:
Some of these 'coincidences' are :

The Solar system formed at the right time, and in the right place to have the full set of metals and elements required for life.
Further from galactic centre, and those elements would not be available.
Closer in, and life would likely be wiped out by a gamma ray burster or nova. Or even get too close to our galaxy's supermassive black hole.

Interesting. I wouldn't have thought there'd be that significant a difference. Is there really that much of a difference in metals the further you go out in the Milky way? I would think that it would be a pretty small fraction of the galaxy where you have to worry about gamma rays or nearby novas. I'm certainly no expert, though.

Lance wrote:
Our solar system is unusual in having stable orbits.

Is that really so unusual? How does he know?

Lance wrote:
Earth is exactly the right distance for liquid water

And, if I remember correctly, the Kepler mission has already detected a few extrasolar planets that are the right distance for liquid water.

Lance wrote:
Asteroids which might bombard the planet are safely tucked away in the asteroid belt or Kuiper Belt.

I would think that, after a solar system reaches a certain age, asteroid impacts on its planets become far less common. I wonder why this guy thinks our own system is unique in this way.

Lance wrote:
Yet Earth received exactly the right type and number of collisions early in its history to provide water.

"Exactly the right type and number," eh? Again, I'm dubious. Is water really that uncommon? Hydrogen is the most common element in the universe, and I think oxygen is the third most common.

Lance wrote:
And lots more similar arguments.

What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

This guy doesn't happen to be a creationist, does he?

Without having read the book, I suspect it's hogwash. Who knows -- if I ever read it, maybe he'd actually convince me otherwise.

A couple of points.

Obviously, not having read the book, I cannot elaborate too much. I am just second guessing the author. However, I have a couple of his books, and he is generally pretty solid and sound with his science.

On stable orbits. The word 'stable' was used in the New Scientist review. I am aware from other reading that the planetary orbits in our solar system are unusual for being circular. Orbits of extra-solar planets are normally elliptical, which would be bad for life, due to massive temperature changes.

On asteroids. I read elsewhere that the presense of Jupiter, well out from the sun, is unusual - giant planets close to a star being found to be very common. Jupiter is the 'vacuum cleaner' of our system, swallowing up cometary debris and asteroids and other lumps of rock or ice in strongly elliptical orbits. Thus Jupiter protects Earth.

Lance wrote:A couple of points.

Obviously, not having read the book, I cannot elaborate too much. I am just second guessing the author. However, I have a couple of his books, and he is generally pretty solid and sound with his science.

On stable orbits. The word 'stable' was used in the New Scientist review. I am aware from other reading that the planetary orbits in our solar system are unusual for being circular. Orbits of extra-solar planets are normally elliptical, which would be bad for life, due to massive temperature changes.

On asteroids. I read elsewhere that the presense of Jupiter, well out from the sun, is unusual - giant planets close to a star being found to be very common. Jupiter is the 'vacuum cleaner' of our system, swallowing up cometary debris and asteroids and other lumps of rock or ice in strongly elliptical orbits. Thus Jupiter protects Earth.

I might be wrong about this. But my understanding is that planets with highly elliptical orbits are easier to detect, because they cause more "wobble" of their parent star. Also, giant planets close to their star are easier to detect for the same reason, and also because they obscure more of a star's light, if you're using the transit method of detection. So, just because we've detected more planets like this, does not necessarily mean they are more common than planets with near circular orbits, like our own solar system.

Lance wrote:What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

It looks like yet another incarnation of the "fine-tuning" argument.

Lance wrote:
What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

I think it's puddle-thinking. There are so many presuppositions in his claims it's not even worth addressing them all. They can pretty much universally be relegated to non-arguments by the anthropic principle.

"alone in the universe", thats enof for me not to take it seriously.

Shagz wrote:

Lance wrote:
And lots more similar arguments.

What do you guys think? Is Gribbin right? Is Earth alone? Is ET a myth? Or is it all a load of hogwash?

This guy doesn't happen to be a creationist, does he?

Without having read the book, I suspect it's hogwash. Who knows -- if I ever read it, maybe he'd actually convince me otherwise.

No, John Gribbin is not a creationist. I have read a couple of his books, and he always presents the science. He writes popular science books, but quite interesting and good ones.

I suspect that Gribbin might be saying something else entirely, like for example that it may be difficult for the same "coincidences" to happen for intelligent life. Without having read the book, I cannot say much. However, I can say that Gribbin would definitely check the facts and observations and present his case with solid science, not hogwash.

Gribbon is a great science populariser. I read his one on chaos theory. I'll give this a look.

The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

Lance wrote:The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

On the other hand, the Fermi paradox only is a problem if you think intelligent alien life is very frequent.

Lance wrote:The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

I tend to ponder this from time to time, the Drake equation is almost worthless, and I say it is what the wiki article calls "They tend to experience a technological singularity", but it doesn't list the obvious, any who become so intelligent realize the absurdity and pointlessnes of it all and wish themselves into the cornfield, or I should say they just cease.

crank wrote:

Lance wrote:The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

I tend to ponder this from time to time, the Drake equation is almost worthless, and I say it is what the wiki article calls "They tend to experience a technological singularity", but it doesn't list the obvious, any who become so intelligent realize the absurdity and pointlessnes of it all and wish themselves into the cornfield, or I should say they just cease.

either that or go on to try and make everyone other intelligent being cease too or better realize that there really isnt any point in life and hence design a simulation in which they live their lives trying to evolve again

cavarka9 wrote:

crank wrote:

Lance wrote:The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

I tend to ponder this from time to time, the Drake equation is almost worthless, and I say it is what the wiki article calls "They tend to experience a technological singularity", but it doesn't list the obvious, any who become so intelligent realize the absurdity and pointlessnes of it all and wish themselves into the cornfield, or I should say they just cease.

either that or go on to try and make everyone other intelligent being cease too or better realize that there really isnt any point in life and hence design a simulation in which they live their lives trying to evolve again

There is a related possibility, since space-time is most likely quantized and finite [in a practical sense], there are only so many possible states, and there will be vastly fewer with significant differences, and vastly fewer with significant interest, maybe the really smart guys figure the game out completely, like checkers or tic-tac-toe, What's left after that? The set of interesting sets might be a lot smaller than we think. They might not care to be a member of a set that would have them as a subset.

Lance wrote:The other great puzzle in relation to this topic is the Fermi Paradox.
http://en.wikipedia.org/wiki/Fermi_paradox

John Gribbin may be presenting a good explanation for this.

I don't understand how this is a paradox. The way I see it:

Given the size of the universe, the chance of there being other intelligent life in the universe is basically 100%; at the same time, given the size of the universe, the chance of us ever coming into contact with it is basically 0%.

What am I missing?

The rational default position according to some people...

"If an entity X is postulated to exist, and no substantive evidence capable of withstanding intense critical scrutiny is present to support the postulated existence of entity X, then the default position is to regard entity X as not existing until said substantive supporting evidence becomes present."

Naturally, I disagree. I think there is 100% likelihood that extra-terrestrial life exists in this universe/multiverse.
Higher intelligence as well.

Lion
I tend to agree.
However, there is no certainty that other civilisations exist in our own galaxy. In the wider universe, then probably. In our cosmic back yard - the probability might be very low.

If no extra-terrestrials are flying space craft anywhere in the Milky Way, then we are seriously, and I mean very very seriously, unlikely ever to meet any.

Lance wrote:John Gribbin has just had a new book reviewed in the New Scientist journal.
Full title : Alone in the universe : Why our planet is unique.

I have not yet been able to get hold of this book, though I would like to.
According to the review, it argues that Earth is essentially unique - the result of a series of lucky 'accidents' or coincidences, that makes it suitable for life, while the odds against intelligence developing elsewhere is slim.

Slim to very slim, but the numbers are so very huge that even slim could be quite a lot, or even and awful lot, relatively speaking of course.

Anyway I think I'll pop this on my Birthday Book list.

Hi Lance,
I dont know if theres a rule about how many civilizations are allowed to exist in any one galaxy at any one time.
Theres a few civilizations here in this galaxy already.
The question about meeting higher advanced life forms might be just a question of time. We might be surprised as to the manner in which we meet them - especially if they exist in a form we understand less than that which we understand quantum weirdness, death, black holes, singularities.
Best regards - Lion (IRC)
PS - I remember you from The Skeptics Society Forum. I got disillusioned with that place after they (Pyrrho) banned karyn and numan for *cough* trolling