are we alone in this universe?
364063
Chances are, yes.\n\n90% of all solar systems are not in a circle so they can not support life.  Of the 10% that are left what are the odds that another planet is moving around a sun where it's not to hot or too cold. Even in our own little solar system there is only one.\n\nSo, if there is life elsewhere, we will never meet them.
21383
I once read a theory that the universe is so big, that there's a chance that not only is there another earth somewhere, but there's probably so many that there's bound to be one exactly like ours.  The universe is huge beyond our present ability to comprehend, and it would be highly ignorant to think that with all the building blocks of life floating around out there that life doesn't exist somewhere else.  Whether we ever find it or not is another question.
385472
Our Universe is the only one that we know of.  Within our universe are at least a hundred billion galaxies.  Within our galaxy (assuming it is normal) there are a hundred billion stars.  That gives us (assuming the averages hold true) roughly 10,000,000,000,000,000,000,000 (ten sextillion) stars in the known universe.
429398
Well, think this, the universe is infinite. Wouldn't be kind of ridiculous to think we are the only smart ones around in such an endless space?
32731
That is unknown. There is no way to find out because we can't exit our universe.
211202
Now, in your main question, you use the generic term "ones," but in the details you use "human beings."  It is possible we are the only human beings, since that refers to a specific pattern of physical and mental processes.  But the only Ones, as in living, conscious, self-aware beings?  That would be statistically amazing, given how many stars there are, and how many planets revolve around our star.  Science fiction has long estimated the number of habitable planets, the number which are in fact inhabited, etc.  I can't say how many, but I'd be truly amazed if we are the only ones.
193508
There could possibly be. Isn't it a little ridiculous to think that in all the galaxies that we are the only humanoid lifeforms? whether or not you believe in God!
596996
Out of 10,000 Billion Galaxies out there. No Doubt there is something out there.\n\nEarth will contact something...but not in our lifetimes.\nI even believe there is another planet like ours out there somewhere.\n\nWe would be very naive to think we are the only intelligent planet in the entire Universe.
435187
Of course we're not. How truly arrogant of human race to think we are the only life in the universe. There are billions of star out there with billion of planets. There is no way we are the only ones.
171562
Thinking that in an "infinete universe" we are the only planet with life is selfish and stupid...\nImagine: We are in an insignificant planet, at the corner of an small galaxy...\nI think is very probable that exists other intelligent life form out there... \nThe question is: How far away? Can we ever met them? \nI think they are far enough, so we won't have some kind of encounter with them...
312883
Yes.\n\nThere is so much of this universe that we do not know.
956138
Yes, you are the creator of your universe. For you those aspects of the Universe do not exist unless your mind is fed with such data by your conscious and unconscious efforts. In a way, everyone of us is the creatore of his world.
586467
No I believe there is other life out there somewhere. The universe is huge so how could we be the only planet to have life?
477542
Dear episodes1979,\n\nI am neither fanatical nor ignorant, and, in fact, have done quite a bit of research on what we humans like to call "supernatural" or "miraculous".\nBased on what I know, I can make the certain conclusion that the universe is not merely limited to the existence of human beings.  We are important, but we are such a minute part of the creative force or energy that seems to surround us at all times.  The greatest of scientists and philosophers will tell you that there are far greater things, worlds, ideas, and concepts at work in our world than we can ever imagine.  Certainly, if there was such enormous energy that this whole galaxy evolved, why should it be limited just to animals, plants, and humans?  The main conclusion one can come to is that, yes, there are those beings, spiritual or physical or both, that are among us in different ways and realities.  And yet there are some completely natural phenomena that early uneducated man propagated as something supernatural and now we wonder what it may be.  Ultimately, everything can be explained scientifically or mathematically, even "ghosts" or "aliens". (As a matter of fact, we have come to call them "aliens", but all that it is is just other diverse life forms, some look like us, who have evolved in other galaxies, universes, etc.)  \nIt is not a fact of whether we believe or don't believe, but rather a fact of how open minded and adventurous we remain.  When we are born, nature provides us with a great openness of heart and mind and a great adventurousness for us to develop even more of it.  How sad it is that some would rather stick to the boring, simple concepts of Life as illustrated by the fact that we reason away our natural desire to be open and inquisitive.  I hope that people who read this will get encouraged on their search for truth.  Or for those who prefer otherwise, it is your choice after all and nobody should judge you for it, I hope you will one day truly investigate at least one of those things that seem to be "taboo" in our society to support (other life forms, us as spiritual beings existing in physical bodies, other mystical creatures).  After all, no matter what the truth is, the ultimate truth about our universe will always be there, and you will only get smarter and wiser if you dare to ask the hard questions and heartfully search for answers.
18963
This is a little hard to answer.\n\nFirst, we haven't found any.  So there's no positive evidence, so it's hard to be really sure. \n\nBut on the other hand, there are billions and billions of planets like ours, and it would be really weird if ours was the only one to have life on it.\n\nSo most astronomers think there's probably life out there somewhere.  I hope we find it.
282593
I do believe it. For one, the universe is absolutely massive and there are billions upon billions of solar systems that we have not discovered. Are we so conceited to believe that WE are the only intelligent species in a universe where there are billions of planets? The probabilities are extremely high that there are a number of other intelligent species. We just haven't found a means to detect them or communicate with them yet.
532226
We Would Be NAIVE To Even THINK That We Are The Only Civilization In This Vast Universe\n\nAnd It Would Be POMPOUS To Even THINK That We Puny Humans Are The Most Intelligent Life In The Universe\n\nwe Are A Primitive Species, And Just Because Were At The Top Of The Food Chain On This Planet\nDont Fool Yourself Into Thinking That We Are The Only Ones\nAnd That We Are The Best There Is\n\nYes I Do Believe That Extraterrestrials Are Here \nAnd I Believe They Are Among Us On This Planet