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Are we alone?
aeon magazine ^ | 6/25/13 | Caleb Scharf

Posted on 06/26/2013 5:40:58 AM PDT by LibWhacker

The rites of spring are many and varied. As a child in rural England, I was once given the chore of finding and rearranging the bulbs of a long-unattended flowerbed. I’m not sure if spring was a wise time to do this from a horticultural point of view. It seemed to me that, having survived the rigours of winter, these hardy little tusks of plant matter probably wanted to wait undisturbed for the Sun’s warmth to penetrate the blanket of earth above them. But such was the issued command, and so I began to brush away last year’s dead leaves and timidly poke about in the rich alluvial soil. To my small self, this patch of ground seemed huge and vacant. That is, until I happened on a tiny unyielding clump, barely distinguishable from the grainy clods around it. I’d discovered my first precious bulb.

It produced a momentary surge of optimism, this bulb. I had searched only a short time and already here was one of my quarry. A somewhat grim afternoon activity was transformed into a promising expedition. There might be a great population of these slippery living forms hiding in the soil. I imagined my grubby little fingers feeling for them, finding them. I imagined how my small trowel would lever up proud handfuls. Great riches and accolades awaited me.

Except that is not what happened. There were no other bulbs, no other signs of life. As I dug, poked and prodded with increasingly sore hands, the already intimidating spread of dark earth transformed itself into a barren expanse of cosmic proportions. How could this be? If I had found one juicy bulb merely minutes into my search, surely this hinted at a wealth of others?

The incident with the bulbs stung my pride. Its puzzling aftertaste didn’t fade until long into summer, when all manner of new things took over my life. But I have had many occasions to remember it in adulthood because it speaks to one of the most fascinating, challenging and frustrating questions that astrobiologists such as myself confront every day in our quest to find life elsewhere in the universe.

There is a commonality between the puzzle of a lonesome bulb in a mass of soil and the puzzle of whether or not we’re alone in the cosmos. Until quite recently we knew of only one life-harbouring planet in a single planetary system — adrift within a universe of more than a billion trillion stars. Our home was that single speck, the lone bulb in a great cosmic garden, and it raised essentially the same question: is this all? Or are there more?

We might imagine that our very existence in this vast universe makes the existence of other life a foregone conclusion, or at least very likely. But that conceit is profoundly misleading; it’s a victim of one of the most challenging aspects of statistical inference and probability. It’s an example of post-hoc analysis or a posteriori probability — that is, the evaluation of the significance of events that have already happened. This is a treacherous terrain, a place where statisticians know to tread carefully, because rare and common events are indistinguishable once they’ve occurred. And this caution is especially important for those phenomena for which we have few or no precedents. Just because life did arise on earth says nothing, in itself, about how likely it is to arise elsewhere.

As I dug in the garden that spring, I knew that other bulbs existed elsewhere in the world. But, until recently, we did not know for sure that other planetary systems existed at all, or what their abundance was, or what the potential for ‘habitable’ planets was. We certainly had our suspicions, some scientific, and some not, but no firm evidence one way or the other. This impasse has now been broken, in a most dramatic fashion, and the implications are extraordinary, for reasons you might not expect.

Since the ancient Greek atomists and the upending of a solipsistic worldview by Copernicus, we’ve toyed with the notion of a plurality of worlds, the idea that the universe is brimming with planets and the stuff that might be on them. But, apart from a few false starts, astronomy was hard-pressed to detect other worlds around even the nearest stars to our Sun. The surrounding cosmos has, when it comes to planets, been a great mound of barren soil as unprepossessing as my childhood garden.

This began to change in the early 1990s. First came the confirmation of planet-sized objects orbiting a distant pulsar — the fast-spinning, ultra-dense remains of a stellar core, left behind from an ancient supernova. Pulsars tend to beam out their pulses of radiation into the universe with astonishing regularity, but this one’s pulses exhibited small variations, tiny, time-stamped changes that revealed the gravitational tugs of planetary bodies. These are likely the zombie remnants of matter left after the star’s explosive death millennia ago, now re-coalesced into entire worlds. Unexpected and strange, these were the first hints of what was to come. Just a few years later, in 1995, a giant planet was detected orbiting a regular Sun-like star known as 51 Pegasi. This measurement was a feat of spectroscopic detective work, which registered the fine Doppler shifts induced on the star by the gravity of an unseen world.

These new planets, and the ones to immediately follow, were utterly alien. The half Jupiter-sized companion to 51 Pegasi orbits once every 4.2 Earth-days, well within the orbit of Mercury in our own system. The next two planets discovered around other stars, 70 Virginis b and 16 Cygni Bb, further disturbed any tidy theory about the structure of solar systems. They have highly elliptical orbits that swing them to and from their parent stars with wild abandon. It was too soon to construct statistics about the abundance of these ‘exo’ planets, but the writing was on the wall: the cosmos makes worlds with an extraordinary diversity.

Since that time, the number of planets known to us has swelled beyond the dozens, the hundreds, and now teeters above a couple of thousand — maybe more, depending on how confident we are in our (largely indirect) methods of detection. These are the subtle Doppler changes in the spectral hues we see as a star tangos about its system’s fulcrum point, or the miniscule dip of light that occurs when a planet transits the unresolved face of its star, dimming the light we see by perhaps as little as 0.003 per cent. Or even the hour-by-hour changes of a distantly glowing stellar backdrop, as the gravitational distortion of a foreground star and its planets focuses and brightens the surrounding field of view. These ridiculously difficult measurements have become state-of-the-art components in the ultra-sophisticated technological machinery of planet hunting.

Indeed, the greatest barriers to expanding our catalogue of other worlds have less to do with our devices and more to do with the fact that stellar astrophysics is a messy business. The upwelling and down-welling of plasma on a star’s visible surface produces measurement errors and statistical noise that can obscure the delicate effects of surrounding planets. Especially those like Earth, whose own presence induces a mere 9cm per second motion on our Sun. Finding planets can be like looking for the gentle swaying of a wheatfield brought on by the beating of a bird’s wings, while all around a hurricane blows.

Despite these limitations, we now know that the diversity of planet sizes and orbital configurations is enormous. For example, the most numerous types of planet seem to be those somewhere between the size of Earth and a few times larger. Since we’ve yet to peer very far into the pool of much smaller objects, this statistic holds true for now. There is a kind of Copernican surprise lurking at the heart of this statistic: it means that the most numerous type of planet is not represented in our own solar system.

There could be about 23 billion stars in our Milky Way galaxy, each harbouring Earth-sized planets with life-friendly temperatures

Many exoplanets also follow orbits that are far more elliptical than any followed by the major planets around our Sun. More puzzling still, the most frequent type of configuration, the one that has earned the moniker of ‘the default mode of planetary formation’, is that of closely packed worlds, on orbits that take mere days or weeks to loop around their stars. These compressed versions of our own system seem, for now, to be far more normal than our own. But if we’re not normal, what are we? That’s a question we can’t answer yet, because our census of stars and planets is still woefully incomplete.

Nonetheless, there is something we can do with this wealth of data. We can make a statistical extrapolation from the worlds we’ve found to those we’ve yet to see. Although these different techniques of planet detection come with different biases and systematic effects, we’re sorting through the issues, and a consistent picture is starting to emerge, a picture of extraordinary cosmic wealth.

Just how many planets are there? This is such an active field of research that it can be hard to know which study to quote, so I’ll simply take one of the more recent and representative examples, whose results are pegged to NASA’s Kepler mission, a telescope that has patiently monitored some 140,000 stars in a distant patch of the Milky Way, looking for those tiny dips of light as mosquito-like planets nip across the face of their parent stars.

In this study, by the astronomers Courtney Dressing and David Charbonneau at Harvard, published in The Astrophysical Journal in February 2013, the focus is on stars smaller than our Sun. Not only is it easier to spot transiting planets around little stars, little stars are far more numerous than big stars. These ones, called M-dwarfs and K-dwarfs, are anywhere from half to one-10th the mass of the Sun, and there are 12 times more of them than of Sun-sized stars in our galactic neighbourhood. In other words, they represent 75 per cent of all stars in our galaxy, an excellent group upon which to work up population statistics. From the data we have now, it looks like planets ranging from half of Earth’s width to four times larger appear to be circulating around 90 per cent of these small suns, with orbits of 50 Earth-days or fewer. Bigger planets, and planets on larger orbits — well, there are going to be plenty of those, too. The estimated number of Earth-sized planets orbiting around these stars at a distance that allows for the possibility of a temperate surface (capable of holding that biological elixir — liquid water) varies from study to study, but it’s coming in at about one per seven systems. Given the concentration of these small stars locally, there is a 95 per cent probability that one of these potentially temperate worlds sits within a mere 16 light years of Earth. There could be about 23 billion stars in our Milky Way galaxy, each harbouring Earth-sized planets with life-friendly temperatures on their surfaces.

Twenty-three billion, give or take a few. This estimate tallies with others. Some studies produce numbers of Earth-sized planets closer to 17 billion, all in different orbital configurations. Others suggest a figure as low as 6 billion or so, but these are just the planets close to Earth in size. If we extend our reach to slightly larger worlds, the places now known as ‘super-Earths’, we’re back into the tens of billions. No matter how you slice the cosmic cake, you end up with a vast wedge of planets that we’d be happy to go and study, perhaps even land on and cautiously tiptoe about. These are mind-blowingly huge numbers. The cosmos makes temperate planets aplenty.

It’s quite striking to see how past thinkers seldom separated the existence of a planet from the existence of life on it

So what does this mean for us, and our puzzlement over our place in the universe? It certainly tells us that Earth is likely one of many other planets in the cosmos with at least some attributes in common. But it feels like it should mean more. Doesn’t it mean something for our questions about whether there’s other life out there somewhere? It does, but not in the way we might first assume.

From the time of the atomists of ancient Greece, the idea of a plentitude, even infinitude, of other places in nature, other worlds, has had considerable allure. More than 2,000 years ago, the philosopher Democritus is said to have written:
There are countless worlds of different sizes. In some of them, neither the sun nor the moon are present; in others, they are larger than ours, still others have more than one of them... some prosper, others are in decline... Some worlds have no animal or vegetable life, nor any water at all.

Here, the ‘worlds’ are really universes — conceptual, metaphorical constructs of other natural places. But ideas like these inspired the later atomists such as Epicurus and his followers to embrace more tangible models of plurality: notions of countless places more akin to real planets and Earth-like environments, all existing within an infinite space. Not everyone was on board, naturally. The idea that new Earths existed elsewhere was fiercely opposed by Aristotle, the great champion of geo-centrism.

But when Copernicus issued his bold cosmological vision of a de-centralised Earth in the mid-16th century, a new generation began to wonder if the universe might be filled with planets like ours. In Rome the priest, philosopher and scientist Giordano Bruno was burned at the stake for heresy in 1600. His heretical actions included his vigorous promotion of the idea that the stars were suns with their own planets. A bit later, in the influential book Entretiens sur la pluralité des mondes, or Conversations on the Plurality of Worlds (1686), the French polymath Bernard Le Bovier de Fontenelle mused on the possibility that all stars harboured worlds like those of our solar system. Piece by piece, these ideas made the universe bigger and bigger, and our place in it smaller and smaller.

Voltaire got in on the act, too. In his satirical work Micromégas (1752), giant beings from Sirius and Saturn puzzle over microscopic Earth and its tiny denizens, discovering to their surprise that humans actually have intelligence. But when these superior beings leave humanity a book that purports to explain the meaning of existence, it is found to contain only blank pages.

The idea that the universe is filled with planets drew supporters from a variety of intellectual disciplines. The natural philosopher Christiaan Huygens was an enthusiast, the astronomer William Herschel took to it, and so did the poet Alexander Pope, who wrote, in 1734:
He, who through vast immensity can pierce,
See worlds on worlds compose one universe,
Observe how system into system runs,
What other planets circle other suns,
What varied Being peoples every star,
May tell why Heaven has made us as we are.

There is a remarkable commonality among all these dreams of plurality. All of them share the unquestioned assumption that planets, or plantlike environments, equate to life, and vice versa. In fact, it’s quite striking to see how past thinkers seldom separated the existence of a planet from the existence of life on it.

Today though, astronomers constantly fret over whether or not a world is the right size, the right composition, or in the ‘habitable zone’ — the region around a star that allows for liquid water. We don’t assume that planets are necessarily occupied. Instead, astronomers and astrobiologists like myself spend our days trying to figure out if there are any planets with the right characteristics to harbour life.

Whether we’re one in a billion, or the product of a predictable life-generating apparatus, the outcome looks the same to the observer after the fact

Yet, for all of this scientific caution, we’re still wishful thinkers. We still want to be able to find life. Like many of my colleagues, I have, on several occasions, succumbed to that alluring view that planets equal life. But the crucial difference between us and past advocates of plurality is that we have information they never had. We actually know that planets are abundant, that they are an atomist’s dream no longer. And yet, the abundance of planets itself actually changes very little about the probability that life exists elsewhere in the universe.

Instead, what it does is fundamentally alter the nature of the question itself, and that in turn leads to an even deeper and rather surprising truth. To understand it, let’s return to my story of the lonesome bulb in a spring garden and bring it into the realm of the cosmos.

Imagine, for a moment, an alternative reality. Imagine we discovered that the Sun was the sole planet-harbouring star in the galaxy, or for that matter the universe. What would this actually tell us about the probability of abiogenesis, the spontaneous generation of life? It’s tempting to think that our existence would be proof positive that, so long as you have a planet, life is extremely probable. If it weren’t, the likelihood that the one planetary system in all existence would carry life would seem fantastical.

But this is post-hoc analysis, which can be misleading. The fact that life exists on this imaginary solitary Earth tells us next to nothing about whether life is probable or highly improbable because if we hadn’t already emerged on this planet then we wouldn’t be able to ask the question in the first place. Whether we’re one in a billion, or the product of a predictable life-generating apparatus, the outcome looks the same to the observer after the fact. It would be just like my childhood self getting his hopes up because he’d quickly come across a bulb in one spot of a great and untilled patch of soil.

Of course, this is not entirely fair. In the real universe, there is a teeny bit of information in the fact that microbial life appears to have emerged very early on Earth, just a few hundred million years after our planet assembled. This does seem to tell us a little about how life arises in the universe, but as a single data point it places few meaningful constraints on the range of rates for abiogenesis. Life could still crop up often, or very infrequently — we don’t know which, because in either case we’d be here to ask the question.

But what if we found a second planet in this imaginary universe, around another star that could potentially harbour life? Suppose too that we were able to test whether or not there was life on this other world. Whether the answer was positive or negative, we’d be able to significantly improve our knowledge about the frequency of abiogenesis. The more habitable planets we found in our pretend cosmos, the more we could test them, in order to build and refine a mathematical model for the likelihood of life.

We live in a universe that allows us to get some measure of our own significance

Now let’s bring ourselves back to this universe, and our galaxy, the one full of temperate planets — tens of billions of them. What do all these planets tell us? They don’t tell us how common life is, but they do give us a shot at finding out. If we lived in a cosmos with only a few planets, we could never deduce the true probability of abiogenesis with any precision, even if they all harboured life — as imagined by earlier advocates of plurality. We might never be lucky enough to find one of these worlds within examining range, and all would be lost among the stellar fields of the Milky Way. The existence of billions of planets gives us a chance to write the equation, a chance to pin down the relationship between habitability and actual habitation. And it could have larger implications still.

Over the past century, scientists have noticed that many of the root physical characteristics of our universe, from the strength of gravity to the values of fundamental constants that determine atomic structure, all seem precisely aligned with the conditions that appear necessary for life to exist. Change a few of these constants and there’d be no stars like the Sun, there’d be no heavy elements like the carbon that builds our complex molecules, and so on.

Of course, it’s pretty obvious that if things weren’t the way they are then we wouldn’t be here to notice it in the first place. In that sense, this apparent ‘fine-tuning’ of the universe for life is just a selection effect, an unavoidable bias of our existing in the first place. This ‘fine-tuning’ of nature is especially mysterious if you suppose that ours is the only universe, the only version of reality that has ever existed. Why should a one-off universe be tuned for the grubby little molecular pieces of our life? It’s a thorny problem that can lead to all kinds of interesting, and sometimes wild, interpretations. But fundamental physics and cosmology might hold the answer to this mystery.

Ever since the American philosopher and psychologist William James first coined the term ‘multiverse’ in 1895, there has been increasingly good reason to think that our universe is actually only one of many, part of a multiverse of other regions of space and time separated by distance and time, or dimension. Some theoretical frameworks suggest that there could be upwards of 10 to the power of 10 to the power of 16 distinct universes. Indeed, our investigations of the cosmos suggest that the same quantum physics of the vacuum that spawned our universe, and the awesome energy of inflating space that blows it up into the kind of place we occupy, is also well-suited to generating all of these other universes. We even have a shot at testing this through astrophysical measurements. If the theory holds, our fine-tuned universe will cease to be mysterious; it will simply be a part of a larger multiverse, a part that turned out suitable for life.

The special thing about our planet-rich universe is that it’s tuned both for life and for finding out about life. If we were back in our imaginary universe with only one planetary system, we would have no way of learning how frequently life arises. We live in a universe that allows us to get some measure of our own significance. There is nothing in our present understanding of the nature of life or the universe that says this was absolutely necessary, yet here it is.

It’s not clear that we’ll ever be able to solve this puzzle. To start with, we need to build that equation for abiogenesis, we have to dig deeper in the astrophysical dirt to find places in the universe that might harbour life, to follow nature’s breadcrumbs, as it were. The strategy is straightforward: seek out more worlds that might share some of Earth’s characteristics, and search their surfaces for the chemical signatures of life. It won’t be easy but, unlike 20 years ago, we now know we have a galaxy’s worth of planets to chase, and we know that if we persevere, the equation will eventually come into focus.

That this work is even possible has, in a very real sense, already changed our universe. Not because it’s told us anything quantitatively new about life elsewhere, but rather because it’s raised the stakes for evaluating our significance, our cosmic loneliness, to a whole new level. Not only are the fundamental properties of our universe aligned, and tuned to, the needs of life, they also promise success in our quest to discover life’s frequency, origins, and perhaps the very causes of this tuning itself. And it didn’t have to be like this at all. If you turn it over in your mind enough times, you realise that Albert Einstein was right when he said: ‘The most incomprehensible thing about the universe is that it is comprehensible.’

Published on 25 June 2013


TOPICS: Astronomy; Science
KEYWORDS: earth; exoplanets; life; universe
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1 posted on 06/26/2013 5:40:58 AM PDT by LibWhacker
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To: LibWhacker

I think within a few thousand light years, yes, we’re very alone. But God’s out there with the same chemistry and physics as here. So, maybe.


2 posted on 06/26/2013 5:47:05 AM PDT by onedoug
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To: LibWhacker
From a purely scientific perspective, it is not yet possible to say if we are alone or not. Statistically it is very likely that we are not, but there is not yet any evidence to support the statistics.

That said, alone is actually good. There is no guarantee that other intelligent beings would be friendly or benign. The could just as easily be lovers of conflict, implacable xenophobes or worse. The residue of civilization can be deadly. Intelligent supermachines like Saberhagen's Berserkers are not impossible, but unintelligent but prolific self-replicating machines would be just as problematic. But even the friendliest extraterrestrial neighbors would surely cause technological, cultural and religious shockwaves that would change human civilization forever.

I can live with alone.

3 posted on 06/26/2013 6:05:18 AM PDT by jboot (It can happen here because it IS happening here.)
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To: LibWhacker
I have had many occasions to remember it in adulthood because it speaks to one of the most fascinating, challenging and frustrating questions that astrobiologists such as myself confront every day in our quest to find life elsewhere in the universe. There is a commonality between the puzzle of a lonesome bulb in a mass of soil and the puzzle of whether or not we’re alone in the cosmos. Until quite recently we knew of only one life-harbouring planet in a single planetary system — adrift within a universe of more than a billion trillion stars. Our home was that single speck, the lone bulb in a great cosmic garden, and it raised essentially the same question: is this all? Or are there more?
Question: Why is Carl Sagan so lonely? (pick one)

    (a) Sagan is lonely because, as a true devotee of science, a noble and reliable method of attaining knowledge, he feels increasingly isolated in a world in which, as Bronowski has said, there is a failure of nerve and men seem willing to undertake anything other than the rigors of science and believe anything at all: in Velikovski, von Daniken, even in Mr. and Mrs. Barney Hill, who reported being captured and taken aboard a spaceship in Vermont.
     (b) Sagan is lonely because, after great expectations, he has not discovered ETIs in the Cosmos, because chimpanzees don't talk, dolphins don't talk, humpback whales sing only to other humpback whales, and he has heard nothing but random noise from the Cosmos, and because Vikings 1 and 2 failed to discover evidence of even the most rudimentary organic life in the soil of Mars.
     (c) Sagan is lonely because, once everything in the Cosmos, including man, is reduced to the sphere of immanence, matter in interaction, there is no one left to talk to except other transcending intelligences from other worlds.

-- from Walker Percy's Lost In The Cosmos: The Last Self-Help Book


4 posted on 06/26/2013 6:28:40 AM PDT by Alex Murphy
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To: onedoug
I think within a few thousand light years, yes, we’re very alone. But God’s out there with the same chemistry and physics as here. So, maybe.

Does that mean you might have to change your Freeper name to twodougs? ; )

Happy Landings!

5 posted on 06/26/2013 6:31:47 AM PDT by Northern Yankee (Where Liberty dwells, there is my Country. - Benjamin Franklin)
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To: LibWhacker

We were going to be the generation that went to the stars. We can’t even send people to the moon. I doubt if we will be able to keep sending people to the space station. We laugh at the story of The Tower Of Babel, yet, we live it every day. Some of us have hearts that long to explore the universe, but, while we can escape the earth’s gravity, we cannot escape the people on earth with all of their fears and needs and jealousies. The realities of earth destroy the dreams of space. And it isn’t overpopulation or pollution or war.....it’s our smallness that holds us back.


6 posted on 06/26/2013 6:43:41 AM PDT by blueunicorn6 ("A crack shot and a good dancer")
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To: jboot

The could just as easily be lovers of conflict, implacable xenophobes or worse.


...but they would have so much in common with earth.


7 posted on 06/26/2013 6:50:41 AM PDT by Idaho_Cowboy (Ride for the Brand. Joshua 24:15)
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To: jboot

If interstellar space travel is possible, I think in the end we may find that the biggest threat to us is other humans — or, rather, former humans. Over cosmic timescales, humanity will move out among the stars and isolated populations of humans may evolve into, or engineer themselves to be something different and, deliberately or not, utterly incompatible with the rest of us.

In fact, evolution and engineering needn’t even be brought into it; we don’t like the Russians, Germans don’t like the French, China doesn’t like Japan, and Arabs hate everyone. And we are all still human beings. The far-distant future could be very bleak, even if the only life in the universe right now is here on Earth.


8 posted on 06/26/2013 6:59:05 AM PDT by LibWhacker
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To: Idaho_Cowboy
but they would have so much in common with earth.

True, like us but with near-godlike technology. That's a bad mix...

9 posted on 06/26/2013 7:00:59 AM PDT by jboot (It can happen here because it IS happening here.)
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To: blueunicorn6

But that smallness is what we have to work with.

I think in the end, I think it will be much like the idea that Ian Banks forwards in his Culture novels: we end up designing vast artificial intelligences that are friendly and benign to humanity and get us to the stars. It is not clear to me that any committee or super-human-brain could do it. A system so smart it can navigate our regulatory structures like walking through a pasture is for us, and yet can comprehend the extreme physics required to get us out there safely and cheaply.

Yes, we can do small very focused missions out, but we really need to solve the energy problems of getting into space. Right now, we sit ourselves on piles of explosives and basically control explode ourselves into space. It will never make for a mass transit system. Even the access means of Virgin Galactic is not incredibly efficient, just leaps and bounds above how we do it commercially now.

Still very dangerous and very fuel intensive.

There has to be a better way...


10 posted on 06/26/2013 7:04:35 AM PDT by Aqua225 (Realist)
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To: LibWhacker

with all the radio telescopes and tech we have not heard or seen a single piece of communication or evidence of Aliens .not a peep. So we are alone. face it.


11 posted on 06/26/2013 7:04:39 AM PDT by Democrat_media (IRS rigged election for Obama and democrats by shutting down tea party)
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To: jboot

statistically you cannot prove a negative, though you can prove a low probability. To prove a negative you must look at all samples.

If you do not look at 100% of the group then there is always a potential that you just haven’t included the few positives that exist in your sample size.

So while observation of life one time proves the positive, we would need to look at every star and every planet to prove the negative and that requires an order of magnitude that is likely unachievable.


12 posted on 06/26/2013 7:15:02 AM PDT by reed13k (For evil to triumph it is only necessary for good men to do nothing.)
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To: LibWhacker
I tend to agree. Human nature does not change. We are as we always have been and always will be.

A complicating factor is the creation of non-human intelligent entities by humans. These counld take virtually any form from useful servitors to berserk destroyers. This behavior is already taking place and can only become more sophisticated. There is a real danger that humans will "foul the nest" with destructive artificial entities before we can "escape" into space. The grey goo scenario isn't really that far-fetched.

13 posted on 06/26/2013 7:34:32 AM PDT by jboot (It can happen here because it IS happening here.)
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To: LibWhacker

“...,Imagine, for a moment, an alternative reality....”

That’s what it comes down to. For crying out loud...the lengths people go to in order to escape the concept of our creator. To escape the idea of being held accountable.

I was raised religious, then became too smart (for my own good) to believe in a God, and considered those that did as weak.

Then I learned about quantum physics, and realized that wave/particle duality and the uncertainty principle was God’s way of saying “you may know this much, but NEVER more than that.”

Sealed it for me. There’s just no getting around it.
Now, with the grace of God, I know better, and my hubris has been humbled.

Can I get an Amen?

:)


14 posted on 06/26/2013 7:48:41 AM PDT by ImaGraftedBranch (...By reading this, you've collapsed my wave function. Thanks.)
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To: LibWhacker

We are the seed of life, one of the first tasks our Creator has given us is to “Go forth and multiply”. Unfortunately the dark one has lead us astray and we have wasted much time and effort in silly games of ambition instead of doing our work.


15 posted on 06/26/2013 7:53:14 AM PDT by fella ("As it was before Noah, so shall it be again,")
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To: ImaGraftedBranch

Unlike many, I see no conflict between the existance of God and the possible existance of non-human intelligent life. Why some find the two mutually exclusive is beyond me.


16 posted on 06/26/2013 8:34:29 AM PDT by jboot (It can happen here because it IS happening here.)
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To: LibWhacker

Here is what we know so far. Life is possible in the universe. Intelligent life is possible in the universe. Processes are universal and certain, outcomes of those processes are not. Natural law operates the same throughout the universe as far as we know. Other natural phenomenon such as comets, planets, galaxies, black holes, gas clouds and stars are universally present. We know that simple organic compounds exist in vast quantities in space. Scientist have proven that these compounds can spontaneously form more complex molecules such as amino acids and even some precursors to DNA. Science has more recently shown that self replicating molecules can form spontaneously from these simpler building blocks including self replicating RNA. Science has also shown that lipid compounds can form spontaneous in hot springs and spontaneously form miscelles, or microscopic spheres. It is reasonable to assume that these miscelles would trap some of these self replicating molecules and the catalyst molecules they require inside. So now you have a simple cell membrane with self replicating RNA inside which utilizes molecules around it to make more of the self replicating molecules. Interestingly, the scientists found that these self replicating molecules were subject to evolution, with the ones that most readily self replicate predominating over time and that these molecules were subject to copying errors producing variation. So We don’t have any evidence that life exists elsewhere in the universe but we can see now some of the ways in which it could arise given the right conditions.


17 posted on 06/26/2013 8:40:52 AM PDT by albionin ( ,)
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To: Aqua225
There has to be a better way

Clarke's Space Elevator from "The Fountains of Paradise" is an elegant solution to the problem of getting into orbit. The advent of nanomaterials has made Clarke's vision seem far less preposterous. But the biggest hurdle to creating a space elevator is not materials science but ecomnomics and politics. Such a machine would be astronomically expensive to build and maintain, and the issue of who controls it would be non-trivial. It is not as if you could move it once constructed, and it is unlikely that we could ever afford to build more than one of them. The world will need a more powerful economic system and a more stable political climate before any space elevators can be built.

18 posted on 06/26/2013 8:42:53 AM PDT by jboot (It can happen here because it IS happening here.)
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To: jboot

With mastery of electro-gravitics the elevator concept is obsolete.


19 posted on 06/26/2013 8:54:57 AM PDT by MHGinTN (Being deceived can be cured.)
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To: MHGinTN
With mastery of electro-gravitics the elevator concept is obsolete.

Perhaps, if electro-gravitics turns out to be more than Art Bell twaddle. But the elevator is built on known physics and materials and is attainable in a timeframe of several decades or at most a century. Electrogravitics-even if real-are a long, long way from being understood or put to practical application.

20 posted on 06/26/2013 9:18:59 AM PDT by jboot (It can happen here because it IS happening here.)
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