Are we alone in the universe?

[MMC]

Some statues perhaps some have seen.

 

[MMC]

Thanks for the reminder. Some of the old religious paintings which contain images, which look like "ufo's" really do spark my interest and curiosity.

Heya Liz. Here are some the History Channel had up.

 

[American]

Some statues perhaps some have seen.

 

[Jack Hays]

I believe he's from France.eace

 

[Buck Ewer]

Are we alone in the universe?

All the hard evidence points to the fact that we indeed are.
There is nothing to contradict the notion that we are unique in the universe.

 

[the_recruit]

Given how absurdly vast the universe is, it's almost a statistical certitude that there is other life. Intelligent life is rarer, but still practically guaranteed.

Unfortunately, even if we were to be lucky enough to stumble upon other intelligent life it's possible, I'd even say likely, that we will be so vastly different that any meaningful communication may be impossible. Neil Degrasse Tyson explains it well. Consider our closest relative, the chimpanzee. We share 98% of our DNA with chimps. We're nearly identical. Yet those very small genetic differences are extremely important. We can barely even communicate with chimpanzees. Imagine trying to communicate with a species that shares 0% of our DNA, maybe doesn't even have DNA, a species that will probably have completely different sensory organs*, an organism that is completely different biologically in every way, an organism that evolved in completely different conditions, for a completely different period of time. It would probably be like, I don't know, a kangaroo trying to communicate with an ant. Multiply that by 1000 and that you might give you some idea of the difficulty we will probably have.

And there's also the technological issue to consider. The odds of us stumbling across a species that's comparable to us in terms of technology (within, say, a 2000 year band of technological development) is extremely slim. More than likely, any species we find will be tens of thousands, more likely hundreds of thousands, even millions or billions of years ahead or behind us. Given the exponential rate of our technological development and how much advancement can occur in hundreds of years, not to mention tens or hundreds of thousands of years, that means if we find an intelligent alien species they will probably still be living in caves or they will be mind-boggling advanced to the point that we might not even recognize them as life.

So I think other life is out there. But I don't think the typical sci-fi view of more-or-less equivalent humans and aliens mingling together at the bar on the Starship Enterprise is the way it's going to be, i'm sad to say.


*except eyes - aliens will definitely have some kind of light sensing organ - that's a well-documented convergent evolutionary trait.

 

[Sarcogito]

Given the size of the galaxy, let alone the universe, I find it HIGHLY improbable, though not impossible, that we are alone. I would bet every penny I own that there is other life out there. I would also bet every penny I own that that life has never visited Earth.

 

[RabidAlpaca]

Are we alone in the universe?

All the hard evidence points to the fact that we indeed are.
There is nothing to contradict the notion that we are unique in the universe.

There's also absolutely nothing to suggest we're alone in the universe. It's rather egocentric to declare us alone when we've explored .000000000000000000001% (if that) of our galaxy, while there are hundreds of billions of galaxies.

Statistical probabilities greatly favor life. Even if the conditions for life are one in a trillion, our galaxy would be teaming with life.

 

[RabidAlpaca]

It depends on whether you believe in the Rare Earth hypothesis or the Copernican principle.

The rare earth principle relies on the assumption that life can only grow under the EXACT same conditions we have, which is rather short-sighted. We have no idea how many different ways life could adapt or form.

Even still, with the chances at 1 in a trillion. There'd be an unbelievably large number of alien societies in the universe.

 

[DDD]

Cloud behavior double's the chances of habitable planets on neighboring near red dwarf (most common) planets (Yang et al, 2013). I believe that there are life forms out there whom to us would be alien because they live elsewhere. Whether they resemble us or other life forms on Earth still remains to be seen for I do not think there was any contact till now.

Why should it be? Did they had the time and luck (i.e., not meteorites or lack of them) to evolve smarter than us in the same time?

They may be more advanced than us or they may not be. If they are I do not think that they are that advanced to visit planets at will and be invisible.

References:

Yang, J., Cowan, N. B., & Abbot, D. S. (2013). Stabilizing cloud feedback doubles frequency of red dwarf habitable planets. Astrophysical Journal Letters, 771(2), DOI: 10.1088/2041-8205/771/2/L45

Cloud behavior expands habitable zone of alien planets

 

[Buck Ewer]

There's also absolutely nothing to suggest we're alone in the universe. It's rather egocentric to declare us alone when we've explored .000000000000000000001% (if that) of our galaxy, while there are hundreds of billions of galaxies.

Statistical probabilities greatly favor life. Even if the conditions for life are one in a trillion, our galaxy would be teaming with life.

The mathematical model promoted by Sagan and others is flawed and completely erroneous. Sagan was a dreamer not a mathematician. His dreams are absolutely based on ego and emotion. Not science nor math.
One could extrapolate mathematical odds of "other " life in the universe IF there were at least one other example of a planet with life on it. No matter how many trillion, trillion possible life bearing planets you site in your model, only one example can be shown that has produced life. Without at least one other example the contention of our uniqueness cannot be refuted or calculated with mathematical odds.

Statistical probabilities greatly favor life.

No. Not enough information to even begin a statistical probability analysis.

 

[Buck Ewer]

Even still, with the chances at 1 in a trillion.

That is pure wishful speculation. No such equation can be calculated with our given data.

 

[RabidAlpaca]

The mathematical model promoted by Sagan and others is flawed and completely erroneous. Sagan was a dreamer not a mathematician. His dreams are absolutely based on ego and emotion. Not science nor math.
One could extrapolate mathematical odds of "other " life in the universe IF there were at least one other example of a planet with life on it. No matter how many trillion, trillion possible life bearing planets you site in your model, only one example can be shown that has produced life. Without at least one other example the contention of our uniqueness cannot be refuted or calculated with mathematical odds.

No. Not enough information to even begin a statistical probability analysis.

I will completely agree that the Drake equation is non-sense. It's an equation where 90% of the variables are based on completely fabricated data. However, the only reason I could see someone asserting that we're likely the only game in town, is if that person has an egocentric view of humanity and earth. I don't see us as all that special in the universe. We are just a blip in time, and all the conditions that created earth exist everywhere else in the universe.

It's also the fact that your assertion only covers one scenario. For you to be right there can't be a single living organism anywhere other than earth. I'm right if there's a single bacteria on a distant planet or floating through space. It's kind of like we're playing roulette, and you bet on a single space, while I'm the house. There are 35 other possibilities for me to win, and only one for you.

 

[marduc]

Once upon a time Carl Sagan used some simple math to indicate that it is likely there are other sentient beings in the universe. Problem is that same math shows how possible it is in a universe "teeming" with sentient life for the different beings never to meet. The universe is unimaginably vast.

Speaking of math we have the Drake equation. There are a lot of variables that are completely unknown and unknowable at this point, but we are starting to get reasonable estimations for the first few variables at least, and those numbers are huge.

N = R * Fp * Ne * Fl * Fi * Fc * F

N = the number of civilizations in our galaxy with which communication might be possible (i.e. which are on our current past light cone);
and

R* = the average number of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fl = the fraction of planets that could support life that actually develop life at some point
fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time for which such civilizations release detectable signals into space

(lifted shamelessly from wikipedia: Drake equation - Wikipedia, the free encyclopedia)

Looking at these variables, we are starting to get reasonable approximations for R, and in just the last decade or so (with a huge boost from Kepler) a decent approximation of fp and a rougher estimate of ne (based on tallying exoplanets in the habitable zone, but even here not ALL of these would count, and there may be potential for life outside of the Goldilocks zone as well ie: a moon such as Europa).

fl we are clueless of, since our sample size is limited to one (and ironically to get an approximation for this variable we would first have to discover life outside our planet to begin with).
fi and fc are both dependent on the variable above (fl) so we are in the same boat still.
L we can fudge somewhat based on how long it took for us to go from early civilization to releasing signals, but our sample size is still one.

Now that we are getting a better estimation for fp and ne we are starting to realize that these two numbers are astronomically high indeed (pun intended). This gives a lot of wiggle room in case any of the other variables are extremely low. It has not been all Kepler here discovering exoplanets, but it has had a fabulous run, and contributed a wealth of data. What would be fantastic IMO is to be able to increase our sample size for fl estimation purposes in my life time so we can narrow down another all-important variable. If we do this it would invariably be within our own solar system, and would lead to a safe assumption that this variable itself would be extremely large as well.

It really is exciting to see the recent developments in exoplanet hunting, and to see some of these variables in the Drake equation becoming much more firm. If we are able to fill in the next variable in the equation then intelligent life outside of our planet will become almost - but not quite - become a certainty.

edit to respond to what I just read from RabidAlpaca in the post above: The drake equation is nonsense in that there is no way of "solving" this equation without actually discovering intelligent life other than ours firsthand (and a large sample size at that). However learning that the first few variables are extremely large allows for much more leeway for the others to be extremely small. Knowing that exoplanets, and planets in the habitable zone are common significantly raises the probability that the answer to this equation is >1.

 

[RabidAlpaca]

Speaking of math we have the Drake equation. There are a lot of variables that are completely unknown and unknowable at this point, but we are starting to get reasonable estimations for the first few variables at least, and those numbers are huge.

N = R * Fp * Ne * Fl * Fi * Fc * F

N = the number of civilizations in our galaxy with which communication might be possible (i.e. which are on our current past light cone);
and

R* = the average number of star formation per year in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fl = the fraction of planets that could support life that actually develop life at some point
fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time for which such civilizations release detectable signals into space

The Drake equation is fanciful BS.

Let's take a look at the variables:

R = This is estimatible.
fp = We have no idea
ne = We have even less of an idea
fl = Completely pulled out of our asses
fi = Building on data completely pulled out of our asses
fc = Still making **** up?
L = based entirely on our development, which is illogical to apply to anything else.

I believe there certainly is life out there, but this equation is worthless. If it had maybe one or two flaky variables, that'd be fine, but 6 out of 7? Worthless.

 

[greyhat]

Can't see how we would be the only living organisms in the universe.

 

[MoSurveyor]

Plus we now know there are particles that are traveling faster than the Speed of light.

You do know that whole fiasco from Sep 11 in Italy turned out to be an error in time measurement, don't you?

 

[marduc]

The Drake equation is fanciful BS.

Let's take a look at the variables:

R = This is estimatible.
fp = We have no idea
ne = We have even less of an idea
fl = Completely pulled out of our asses
fi = Building on data completely pulled out of our asses
fc = Still making **** up?
L = based entirely on our development, which is illogical to apply to anything else.

I believe there certainly is life out there, but this equation is worthless. If it had maybe one or two flaky variables, that'd be fine, but 6 out of 7? Worthless.

See my edit in the post above. It is only useful for estimation purposes - and very rough estimations at that. Fp we have a much firmer grasp on than we did say 20 years ago and can make a somewhat reasonable estimate by extrapolating from what we have now learned, Ne as well (but this still only accounts for "Goldilocks" planets, and discounts possibility of life in other environments). If you look at the rest of my post above I do acknowledge that we have no clue on the others, and have no way of knowing at present, but learning that what few variables we are able to get a reasonable estimation of are very large allows us to at least realize that the completely unknown variables can be very very low and still be significant.

 

[MoSurveyor]

“The universe is a pretty big place. It’s bigger than anything anyone has ever dreamed of before. So if it’s just us…seems like an awful waste of space.”

-Eleanor Arroway, Contact (1997)

 

[Buck Ewer]

the only reason I could see someone asserting that we're likely the only game in town, is if that person has an egocentric view of humanity and earth. I don't see us as all that special in the universe. We are just a blip in time

I am an atheist and I harbor no supernatural delusions about any supernatural egocentric qualities of humans or of earth.
The only truly exceptional quality we seem to posses is that we have life here, and that has not been demonstrated to be anything but unique.
There are no winners or losers in this controversy ... only those who prefer to be be deluded by dreamed up mathematical odds to support wishful thinking and pragmatists who are willing to accept the limits of the reality that we know.

 

[Buck Ewer]

See my edit in the post above. It is only useful for estimation purposes - and very rough estimations at that. Fp we have a much firmer grasp on than we did say 20 years ago and can make a somewhat reasonable estimate by extrapolating from what we have now learned, Ne as well (but this still only accounts for "Goldilocks" planets, and discounts possibility of life in other environments). If you look at the rest of my post above I do acknowledge that we have no clue on the others, and have no way of knowing at present, but learning that what few variables we are able to get a reasonable estimation of are very large allows us to at least realize that the completely unknown variables can be very very low and still be significant.

This is not science.
This is not even math.
This is pure conjecture and wishful imagination masquerading as math by taking on the appearance of an equation without any tangible content.
Sorry but the Drake equation is not even an equation.
If you make up an equation where all of the elements are guesses then the answer can only be valued as a pure guess. The conclusion can not have any value beyond that.
In the end although you have gone through all the appearance having done scientific math ... all you have really done is project a conjectural guess. Mind you not an estimate, but a pure guess where the vast likelihood is that your answer is completely wrong.

 

[marduc]

The Drake equation is fanciful BS ...

my internet crapped out on me, but I was trying to add the following in response:

What I am saying is essentially the same thing you said in your first post in this thread Alpaca.

We've been finding boatloads of habitable planets in our backyard with the Kepler telescope, suggesting that there is an astronomically high number of habitable planets in our galaxy, and even more in the universe. I would think it extremely statistically unlikely that we're the only living beings.

To rephrase what you said here: "We are learning that Ne is most likely astronomically high and I would think it extremely statistically unlikely that Fl (fraction of planets with life)= 1/x (where x is number of planets, and 1 is earth)."

Since these variables are dependent on one another this also extrapolates to N (the solution of the equation) to - an admittedly - lesser degree. Knowing that one variable is extremely high makes it much more statistically likely that the others are >1 (to be more precise, for those that are fractions such as the fraction of planets that have life [Fl]: >earth/x).

 

[MMC]

You do know that whole fiasco from Sep 11 in Italy turned out to be an error in time measurement, don't you?

Heya MOS. :2wave: Were you talking about CERN?

Do you think all those that were Military and reported sightings of UFO's and USO's do not know what they are talking about.....when encountering craft that does things that Military and Civilian pilots confirm that we cannot do?

 

[Sarcogito]

This is not science.
This is not even math.
This is pure conjecture and wishful imagination masquerading as math by taking on the appearance of an equation without any tangible content.
Sorry but the Drake equation is not even an equation.
If you make up an equation where all of the elements are guesses then the answer can only be valued as a pure guess. The conclusion can not have any value beyond that.
In the end although you have gone through all the appearance having done scientific math ... all you have really done is project a conjectural guess. Mind you not an estimate, but a pure guess where the vast likelihood is that your answer is completely wrong.

I agree that any math or calculations used to attempt an estimation at the likelihood of extraterrestrial life is BS. We have a sample set of one to work with. However, based on what we do know about the possible ways in which life could have evolved on earth and given the vast number of potential planets out there, it is not BS to believe that it is more likely than not that life has evolved elsewhere. And one can say that without attempting to assign a probability to it.

 

[marduc]

This is not science.
This is not even math.
This is pure conjecture and wishful imagination masquerading as math by taking on the appearance of an equation without any tangible content.
Sorry but the Drake equation is not even an equation.
If you make up an equation where all of the elements are guesses then the answer can only be valued as a pure guess. The conclusion can not have any value beyond that.
In the end although you have gone through all the appearance having done scientific math ... all you have really done is project a conjectural guess. Mind you not an estimate, but a pure guess where the vast likelihood is that your answer is completely wrong.

Did I claim it was anything but a guess or an estimation? no

even though we cannot plug and play with known variables, if - and that is a big if - these variables were known then it would be a lot more useful.. I do not think anyone would think that it is anything but a guide for guesstimation purposes.

Everyone is coming down on me here (well if everyone is 2 people), look all that I am saying as that recent discoveries that suggest planets are plentiful substantially increases the probability that we are not alone.