Kepler's First Found Planet in Habitable Zone of Sun-like Star

[SiberianTiger]

As you've pointed out, there are far too many unknowns to be that specific. My only claim is that extra-terrestrial life existing or having existed significantly lowers our chances of long-term survival.

I see your point, but it still sounds like a fallacy. Probably, there is some missing denominator probability in the equation.

 

[T.Neo]

Assuming a Gaussian distribution, even discovering a bacterium would pretty much mean we're dead.

:facepalm:

I mean the whole theory is built on unproven assumptions.

I think it is built on nonsense methodology and assumptions, including the Fermi paradox, which basically amounts to: "we haven't yet seen aliens doing a bunch of stuff some people think they would do, therefore aliens don't exist".

 

[Jarvitä]

I see your point, but it still sounds like a fallacy. Probably, there is some missing denominator probability in the equation.

P(FF) ... the probability of the great filter being an event in the future
P(ET) ... the probability of extra-terrestrial life existing or having existed

Apply your best guess as you see fit.

[MATH]P(FF|ET)=\frac{P(ET|FF)\times{}P(FF)}{P(ET|FF)\times{}P(FF) + P(ET|\neg{}FF)\times{}P(\neg{}FF)}[/MATH]

---------- Post added at 06:07 PM ---------- Previous post was at 05:55 PM ----------

"we haven't yet seen aliens doing a bunch of stuff some people think they would do, therefore aliens don't exist".

The main alternative explanations of the non-visibility of ET life everywhere are:

1.)That we're the first intelligent species to arise in a galaxy of a 100 billion stars that's 10 billion years old.

2.)That every other intelligent species has decided not to settle the galaxy and stood by that decision for billions of years.

The first option might be valid if we discover our system to be somehow unique, or that the entire galaxy was unsuitable to life until about the time it started on Earth.

However, if this galaxy is anywhere near as planet-dense as the Kepler sample and one in a million planets holds life, the second hypothesis is entirely ridiculous. If it's that common, than the odds are ridiculously low for us having been the first.

 

[T.Neo]

However, if this galaxy is anywhere near as planet-dense as the Kepler sample and one in a million planets holds life, the second hypothesis is entirely ridiculous. If it's that common, than the odds are ridiculously low for us having been the first.

Wrong, on various levels:

1. You assume that sapient life arises on habitable planets readily. This need not be the case and there are a plethora of evolutionary paths that don't lead to sapient life (Earth is a good example). The probability of sapient life arising could be strikingly low.

2. You assume that every sapient species has the physical or eventual technical ability to 'settle the galaxy'. This isn't necessarily the case, as historical and zoological factors on Earth can attest.

3. You assume that 'settling the galaxy' is an amazingly attractive proposition. This is not necessarily the case, and the issue could differ for different species.

4. You assume a particular model for galactic settlement that does not necessarily mesh with what could occur in reality (near identical problem as with the Fermi paradox).

 

[SiberianTiger]

P(FF) ... the probability of the great filter being an event in the future
P(ET) ... the probability of extra-terrestrial life existing or having existed

Apply your best guess as you see fit.

[MATH]P(FF|ET)=\frac{P(ET|FF)\times{}P(FF)}{P(ET|FF)\times{}P(FF) + P(ET|\neg{}FF)\times{}P(\neg{}FF)}[/MATH]

We do have a MATH tag? Cool.

The main alternative explanations of the non-visibility of ET life everywhere are:

1.)That we're the first intelligent species to arise in a galaxy of a 100 billion stars that's 10 billion years old.

2.)That every other intelligent species has decided not to settle the galaxy and stood by that decision for billions of years.

How about the limit of speed of light and huge mean distance between planets suitable for life preventing all sensible ways of settling the galaxy? To the point that even highly developed alien civilizations are confined to their home systems' neighborhood?

 

[Jarvitä]

How about the limit of speed of light and huge mean distance between planets suitable for life preventing all sensible ways of settling the galaxy? To the point that even highly developed alien civilizations are confined to their home systems' neighborhood?

The galaxy is a hundred thousand light years across. The time scale in question is on the order of a few billion years. One ten-thousandth of a c isn't that unrealistic an expectation at all.

 

[T.Neo]

The galaxy is a hundred thousand light years across. The time scale in question is on the order of a few billion years. One ten-thousandth of a c isn't that unrealistic an expectation at all.

Velocity for an object to cross the galaxy in a certain period of time is one thing, performing actual settlement with it is another matter entirely.