# Probability and Life on earth

1. Dec 22, 2005

### VonWeber

2. Dec 22, 2005

### SGT

They use bogus arguments. From the second link you proposed:
Astronomer Victor Stenger has ran a simulation where the main physical constants were varied ten orders of magnitude (not one part in $$10^{40}$$) and found that almost all combinations gave rise to universes and for 50% of the possible universes the lifetime of stars would be greater than a billion years.
This is not true! Of course first generation stars lack the heavy elements necessary to life, but second and third generation ones can have those elements from the supernova explosions of the first generation. Since very massive stars, the ones that go supernova, are very short lived, one billion years after the Big Bang there were enough heavy elements in the Universe that allowed the formation of planets and possibly life.

3. Dec 22, 2005

### Phobos

Staff Emeritus
It is not known what "the required range for physical life" is. What the heck is he basing those probabilities on?

The "strong antropic principle" says that (the universe is made to fit humans). The "weak anthropic principle" says the opposite (humans fit into the universe).

4. Dec 22, 2005

### Staff: Mentor

You can play around with the Drake equation all you want, but the Anthropic Principle provides an easy escape: even if the odds are 1 in a billion, that all-but guarantees that someone, somewhere will be able to ask that question (since there are something like 100 billion stars in this galaxy). We just happen to be here. But we could just as easily have been on a planet around any one of a billion other stars.

The odds of getting any particular starting hand in Texas Hold 'em (2 cards) are 1 in 2600 - but that doesn't mean you should feel lucky to get a 7-2 off-suit.

To use probability as an argument for ID is a misuse of probability.

5. Dec 23, 2005

### G01

I don't see why ID gets as much plubicity as it does. Sure you can say a universe that does support life is very improbable. THAT DOES NOT MEAN GOD CREATED IT. ALL IT MEANS IS THAT ITS IMPROBABLE. This is why ID is not a real SCIENTIFIC theory. No matter how improbable something is, it does not necessarily proove that God is behind it. A scientific theory needs a testable hypothesis and you can not test for God, no experiment you can think of will ever give you a yes/no, proven/disproven answer as to whether god exists. Hence you can't test for god, so ID CANNOT be a scientific theory by definition. This also applies to any other Intellignt Designer; Budda,Allah, The Force, etc.

Don't get me wrong I believe in God and I believe in Science. I also believe that Intelligent Design is destroying both of them.

6. Dec 23, 2005

### SGT

Actually, the probability of a Universe that supports life is 1. The probability of any event that has happened is always 1.
The a priori probability of a life supporting universe is debatable. In the article of Victor Stenger for which I provided a link in my previous post, he shows that there is a high probability that a random universe, with different values of physical constants, could support life, even if this life would be very weird, compared to earthly life.

7. Dec 23, 2005

### Phobos

Staff Emeritus
Because it is a well funded & organized political movement that appeals to any casual observer/layperson that has any religious belief whatsoever.

8. Dec 23, 2005

### G01

Good point. I like science when politics stays out of it. I think my research interests are going to have to be in something that lay people and governments don't care about. Too bad I'll have no place to get funding from lol

9. Dec 24, 2005

### VonWeber

Well, I'm really wondering how good the numbers are. Maybe I should have posted in one of the math forums. He has stuff listed like "local abundance and distribution of dark matter." Then he gives a probability. It makes me wonder if there aren't some errors in the methods the probability is calculated? Do we even know enough to justify making these sorts of calculations? Is everything to exist in the way it does here so incredibly contingent as he's attempting to make it seem? Things like that.

10. Dec 24, 2005

### SGT

He tosses all those numbers without explaining how they influence life. What would happen if the abundance of dark matter was 10 times greater or lesser? Probably nothing.

11. Dec 24, 2005

### Bystander

When they count density a dozen or more times under different names, it's a pretty dead giveaway that it's all codswallop.

12. May 4, 2009

### zvz

It is true in a case of a god, but is not in the case of the God (biblical). Existence of biblical God may be simply falsified by observing an extraterrestrial intelligent life (since it is not implied by Bible). So, according to Popper`s criterion (you meant it, seemingly, stating ID to be "not a real SCIENTIFIC theory") the ID may be considered as "SCIENTIFIC theory", nevertheless.

P.S. Sorry for my English, I understand it is not blameless.
P.P.S. Sorry for raining so old but still interesting topic.