What We Still Don't Know?

Ratings: 7.70/10 from 23 users.


What We Still Don't KnowThe Universe is still a place of mystery and wonder. As a cosmologist, I am exhilarated that we can make some progress towards tackling what seem very fundamental questions.

These programs focus on: Was there a beginning? Whether we are alone? What's the future of the cosmos?

What is the nature of reality? With each advance, new questions come into sharper focus. The key issue is what we still don't know.

Sir Martin explores the possibility that life exists on planets beyond our own. He unveils an unsettling scientific debate that has startling consequences for us Earthlings. Do you believe in aliens? If not, a quick glance through these pages might change your mind!

Everything you thought you knew about the universe is wrong. It’s made of atoms, right? Wrong. Atoms only account for a measly 15% of everything that exists. The mass of the universe consists of something so mysterious and elusive that it has been dubbed ‘dark matter’.

There is a fundamental chasm in our understanding of ourselves, the universe, and everything. To solve this, Sir Martin takes us on a mind-boggling journey through multiple universes to post-biological life. On the way we learn of the disturbing possibility that we could be the product of someone else’s experiment.

Episodes: Are We Alone?, Why Are We Here? and Are We Real?

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43 Comments / User Reviews

  1. Randall Klopping

    In the spirit of the paradox, I laughed when scientists speak of aliens coming to Earth and bringing us world peace. Even if it is a benevolent race, willing to share all their knowledge, would the human race suddenly behave different from the nature we have so demonstrated throughout history? Its like when people talk about time travel I often laugh because they all want it so bad that they don't think about the fact that we can't even handle the present with any real efficiency, thus likely meddling with the past would be a mega-disaster! In one of my artworks, Meddling with Space-time, I represent that it would be wiser to stand in the middle of a field during a massive thunderstorm while holding a 20 ft steel pipe in the air, than to interfere with the past if it is even possible to do so.

  2. @ randall

    there is no such thing as human nature, enviroment creates the way peeps act. if there is enhoug for everyone of the basic things such as food an there is no media system saying you suck if so dont drink this beer or buy these clotes then peeps will focus on having a good time a natural way, spending time togheter and having fun (proof is travel broke country's and visit pour family's) . you dont need anything besides these basic things and if you want the earth to be a better place. the old bad past is only bad because peeps are suppres, give their power away to greedy men and scarcity is perpuiated in the best interest of that little group of power hungry freeks.

    if aliens come here and intent to save us from all the bad things that are done to us and we are forced to do to eachother by the richt they will most sertenly kill all the super rich weapon making peeps and the energy monopoly holders. those peeps are responsible for every bad thing in the world today and we could unite for peace and a better planet if we all agree it is in all our best interests to use the geotermal and tidalwave and sun and wind power and stop producing weapons and educate peeps on how to be creative and productive and responsible human beeing.

    i could go on and on but is really very easy.

    1 you must know there is enhoug on the planet for every body to have a perfect live, have enhoug food, have smart kind and beeing able to travil.

    Very important be aware of the choices you make and there effect on the world. supporting greenpeace may save a whale but supporting the war with your taxes may put death upon 1000 of peeps in other country's. Wat do your choices leed to and what choices do you have

    2: be responsible for your own enviroment en choice making in life, the end of politicians today, mobilise free energy en the 500 time better solar cell (google 12 year old boy 500x better solar cell) stop producing weapons, if there is enhoug energy why fight wars about recources? oke i know about satanist and other rich peeps like that but they can only get away with it becouse we let them every day instead of stopping support of the system.

    (rich peeps sacrivice cillians in the past for their monitairy gain and fun i cannot think of a reason why today this is different since i still see the same things going on with the same kind of choice makers behind it)

    3: use al the above alternatives wisely and live with wisdom to never harm your own way of living or that of someone else than we can all exploure space, inner and outer for ever and ever (quote from bill hicks comedian)

    its all your choice do you support the system we live in today or do you really want to make the system fair and balanced en energy to be free, we all make the choice every minute to do the one or the other, dont protest wat you dont like! MANIFEST WAT YOU REALLY WANT IN LIFE BY CHOOSING JUST THAT EVERY MINUTE OF THE DAY. The only protest you should do is stopping your own money supply to those who are corrupt to the welbeeing of the earth and its inhabitants.

    Think about this :)

    thanks for reading sorry bout the sucky grammer and repeating of points.

    Make the right choice en we can all live in abundance for ever and ever. the end of greed and corruption is today if we collectively chose it

  3. Concon

    Just a tought, at the first clip. Between 26.55 and 27min
    why are there a women in the back riding a bicykle backwards?? :S

  4. shay

    Yes that’s the one, I love that stuff, answering the question with a question, or you kind of knew anyway.

  5. Dean Morrice

    A truly fascinating topic, I believe that the age of Aquarius will surely lead us to the answers we have been waiting for for thousands of years, Humans cannot be the pinnacle of evolutionary intelligence can they?

  6. sickuminatus

    the range of biologies on this planet may have to do with the creative devas that are at work here

    too bad that the negative influences seem to be gaining the upper hand through greed and powermongering

    but maybe that is the definition of necessary evil, although i think not

    necessary evil is more like having to live in your own feces not to speak of every other species' feces

  7. holly

    water isnt an element???

  8. FoxyMethoxy

    no water isn't an element. but it's made out of elements. two parts hydrogen, one part oxygen.

  9. Chris

    Sir Martin raises an excellent point: If the universe is filled with life, where is everybody? If intelligent life started on a planet a billion years older than the earth, they would have had many millions of years head start to develop FTL travel. Since they have not, we are forced to the conclusion that the distances are just too great. Even theoretically (let alone practically), the sources of energy available to cross those distances are just too small.

    It's like contemplating the practicality of time travel. If time travel were possible, we would already know it. The laws of physics are stacked against anyone ever visiting the earth. As Stephen Hawking said, "If the government we have was hiding a secret as big as earth being visited by aliens, it would be the sole thing they would be doing well."

    Just enjoy your Star Trek reruns.

  10. WTC7

    Hi Chris!

    Star Trek allow for a bit of imagination - imagination that builds upon the existing science and technology. They take current achievements somewhat further, but not too far as we witness an incredible pace of technological progress on a daily basis. In a hundred years, Star Trek technology may be long overrun. (It's true that I love ST & what they represent :-))

    I believe that being religiously entrenched in our existing scientific knowledge and not allow for the possibility that we actually may learn much more as we move on is unwise and shortsighted. We may well find out that we were wrong about much we believed were undeniable facts. (Repeating that we believed not so many centuries ago that Earth was flat or that it was the center of the Universe would be redundant, I guess.)

    Have we explored all the sources of energy to be able to say that moving between the stars is impossible? Are we aware of all the sources of energy that exist? The capabilities that some people possess, as much as we don't understand and can't explain them, like telekinesis for example, are worth considering. Our own minds are still a mystery to us, let alone other things outside the reach of our eyes and understanding.

    And what about the possibility that there exist more dimensions than the one we can perceive? If I remember well, Buddhism speaks of six or seven of them. Even in Christianity, angels and demons may be nothing else than entities from other dimensions that our ancestors had contact with. Traveling from one dimension to another is not something any of us could claim being an expert on.

    So, where is everybody else in this Universe? Is it possible that we simply can't perceive them? I think it is, in particular when we know that our perception is rather imperfect.

  11. Lee

    If the distances involved in space travel turn out to be insurmountable,we might end up trading signals with other life(if it exists) and having to leave it at that...how disappointing that would be.

    Who can deny though, that the future of our race depends on spreading our seed in as many worlds as possible.Short of a divine hand swatting away everything that threatens us.

    I invite you all to take a moment to thank Jupiter(in all its gassy splendor) for helping us make it this far :P

  12. Chris

    Hi WTC7,

    Well, I think that this is my point exactly. Have we explored all the energy/technological possibilities that could be used for FTL? Surely, the answer is that we have not. So does that mean that we should keep trying? Sure, why not? I'm sure we will discover all sorts of new and useful science and technology in the effort.

    However, my point was this: According to the numbers, there should be thousands of civilizations in our galaxy that are a million or even a billion years older than us. It follows that, if FTL were possible, if travel between star systems was possible, if various alien worlds visit one another in all the vastness of space, they would have surely visited us already and we would have evidence of it.

    As the preacher says, "There is nothing new under the sun." In other words, if it were possible, it would have been accomplished long ago.

  13. Allister Grey

    Ha ha - We are alone. They have convinced themselves that Billions and billions of year + nothing gives life. Therefore they think billions and billions of planets must have life. It is this type of arrogance that keeps them away from God and in their little world of Macro-evolution.I know this type of statement will have them frothing at the mouth but the arrogance of man knows no limit.

  14. ez2b12

    @ Allister Grey

    What is arrogant, in my opinion, is to look out on this universe of unimaginable size, variety, and complexity and think- Man is the only intelligent life possible. Thats right I do not just believe thier is life out thier but that it is probably intelligent in a few rare cases. 100 billion- billion galaxies each containing 100 billion-billion stars, a universe full of carbon and water, the fact that life is tuogh and persistant as hell- and you believe this is it? And you say we live in a small world. The world of reason and scientific method is absolutedly facinating and exhilarating- It creates a beautiful world of truth and beauty. I am sure your life as a religiouse person is great for you but, do not presume to tell us that our world is "little". I used to spend my time as an atheist trying to attack theism and preach the wonders of science. I no longer do this as I see now that it makes you look small when you make generalized predjudicial statements like yours above. Why do you come to a site dedicated to scientific education and discussion and start making juvenile insulting comments toward those that are here to learn. I do not go to religiouse sites and condescend or insult people for being religiouse. secularism is on the rise, second largest group in America- largest of course being the Christians. Soon we will be a recognized voting block and will start to exert control over governmant just like the Christians have done for so long. Things are changing, for the better in my opinion. When I talk with anyone under say twenty-five online they are not religiouse at all. It is not even a issue to them. They think nothing of having no faith in any god period. To my generation even if you are atheist you think about religion and the fact that you do not buy it. These kids never even think about it, just like it should be. They seem to have descent morals for the most part and successfull lifes, all without any religion of any kind. Soon all the old folks like me (maybe you too I dont know your age) will die off and this world will the better for it. The predjudice and ignorance of my generation and those that came before is inexcusable.

  15. Richie

    Right wingers want us to believe in the whole "human nature is war and greed" because they are raised to be greedy and blood thirsty animals.

    Us civilised folk know better.

  16. J doe

    @ ez2b12

    Even though i agree with Allister, you had a reasonable point until the end. SOME people have no faith. your making a huge generalization that people under 25 have no faith in religion. You say they dont even think about it. I agree with you on that because our education system teaches us not to question the "Facts" of science or the Government. These are kids that dont think for themselves and probably don't care about science either. I for one disagree with organized religion because of the potential corruption of any authoritative organization. One can have faith in God and creation without associating with a Church. You closed by saying ignorance is inexcusable by saying the most ignorant concept a person can argue. That point being- the world would be a better place without all those that disagree with you. If you believe that, then take your place in the Hitler Youth.

    As a filmmaker and someone who watches lots of documentaries, I'll tell you to consider the fact that this documentary does not give alternate opinions, it gives one specific message to server their purpose which is just as "preachy" as any church service i've ever sat through. A message which is entirely based on the foundation of how the unknown spark of life came to be. The rest of the message is simply a tool to disprove creationism. Albert Einstein said "Science without Religion is lame, and Religion without Science is blind." Religious people dismiss science, and science dismisses religion. But we need both. We dont hear about the Astronomers that believe in God, because their peers discredit them and call them ignorant.

    Imagine this documentary crediting God for creating the spark of life and setting the wheels of the Universe in motion! Their belief is that chemistry can create life Then why cant we create life from basic elements on earth? They believe in the Big Bang. How does that mass get there to cause such an explosion in the first place? These theories are no more convincing or complete and to me, less believable than Intelligent Design.

    Try exploring all possibilities and have an open mind to other peoples views. Have tolerance for those that disagree with your beliefs because weather you believe in God or you believe in science We Are All One.

  17. toddy

    why we haven't discovered life beyond our planet, may i offer a possible analogy that might explain it. Let say when you walk into a forest and turn over 10 rocks and see no insects or worms or such does that mean there aren't any? It just means that you didn't look in the right place or better yet if you looked under those same rocks with a microscope you might find a place teeming with life. As it is well known that some form of life can exist in areas previously thought of being to hostile to support life(look at the extremophiles in the hot vents around the world). So why not elsewhere in the universe? I was brought up in a very religous household and even though i don't share the dogma of my parents, I was taught that God was a God of creation and to me he wouldn't be satisfied with creation of life on one planet otherwise it might end up being a very lonely place.

  18. John

    I have watched a lot of documentaries pertaining to cosmology, and I must say this one goes into more detail. With each question that it tries to explain, it goes on to another question that derives from the first. This makes it fascinating to watch, and makes it easier to understand things like evolution, atoms, and dark matter. I highly recommend watching this doc in order..."Are We Alone?", "Why Are We Here?", and "Are We Real?"

  19. lazer

    @ ez2b12 as

  20. lazer


  21. lazer

    @ ez2b12 as a 25 year old, i have to agree with you on your point that my generation, generally speaking hasn't much of an interest in religion. Its undeniable that we are lesss religious than our parents, and grandparents generations.i too look foward to a future where such teachings(religious) are no longer focused on the mainstream ciriculam. i do have to point out that your comment on, us "not even think about religion" is a little dismisive and misguided. i believe we do ponder and wonder about these things as much as your generation or any other, its just that we are more informed then your generation, and allowed more free thought and control, to educate ourselves regardless as to what is on offer. mediums such as the internet(like this forum right here) and even television and others have bred a whole new self-informed generation as is obviously our evoloutionary destiny.also id like to just add, these wonderfully complex questions that we so desperatly seek the answers too, that we strive to answer in our lifetime, not only almost always lead to a bigger question, but they drive us. answering these questions would ultimately lead to the destruction of man kind, by means of being over educated to the point where we know everything, the point to all this, what happens next after we die, not having or even having the answer we wanted would take the will to live away from this do or die mentality that got us this far.which of course could be the logical end to the circle of life, our evoloutionary destiny.we want the answers, but so desperately don't want the answer, or need the answer.. i guess its the journey that counts. peace. 1luv

  22. reppin' rez

    this video, even to the most amatuer, is clearly alien propergander. i dont want to scare anyone, but you might be interested in the backwards bike riding, as seen at 26min55seconds. this is obviously either a glitch in the alien programming or a sign to those who are down, to rep. its common knowledge among those rep on the reg, that our alien overlords expect us to rep,and rep hard. i take a risk in informing common folk of this phenomenon, as the aliens may not be impressesd, and i am expecting to be silenced by the powers that be very shortly.but informing the less intellegent of us humans has made it worth it. so in closing all i ask of you, my bretheren, is to rep, and rep it hard.

  23. Joe Johnson

    Absolutely there is life throughout the known universe without doubt - the one universe that we know of. There are probably many universes with a finite number of galaxies within each universe. Why would the earth be any more special than any other planet in any other solar system that has water and is a similar distance from it's own sun. There is probably a good chance that there is life right here in our own solar system on Europa for example. It probably has already been discovered but the powers that be have kept these discoveries from the public.

  24. Jack1952

    Microbes on Europa is a state secret. Yeauh.

  25. Anthony Pirtle

    I will never understand why ignorant religious people feel justified calling anyone else arrogant, since they are the only group who, without a shred of evidence, claim to know the answers to the most important questions in the universe, and who think their religious opinion trumps all the collected evidence of the past several centuries.

  26. alastair1

    For "Are We Alone": It is so interesting to think that life evolves with a somewhat rigid set of laws, possibly creating earth-like organisms on other planets. Although if there was life on a planet that had a billion year head-start, and a human like creature had evolved, surely there would be an abundance of inorganic intelligence on that planet. Inorganic intelligence will be the ultimate intelligence and if we don't die this century we will see this happen, as humans integrate themselves with computers and intelligent machines. So I believe truly intelligent alien life will be inorganic (or at least half half)
    Fantastic documentary!

  27. Alex Kilpatrick

    umm did anybody else notice the guy riding the bike backwards at 27.00...WTF?

  28. Christopher Fox

    the strangest about the guy riding the bike backwards at around 26:55 is that he seems to be coming out of nowhere! watch the next gap between the columns. he isn't there.

    Very funny guys cutting that video

  29. gsjikwblao

    Based on the assumption that vast amounts of dimensional space is purposed to contain vast amounts of physical bodies wherein consciousness is anchored, I would agree. But if the purpose of physical existence is to produce consciousness, then it would only be necessary for one example to arise. Consciousness must have something to be aware of. The universe provides that necessary something. Applying perceptions of scale that are common in our every day experience if life may be misleading.

  30. Greg_Mc

    HAHA!! Haven't watched this yet but was reading the comments and decided to check out what people were talking about in reference to some guy riding a bike backwards at around the 27 minute mark of the first vid. Lol he does just come out of nowhere and rides out of sight of the camera. I will have to watch the doc now and see if it may have something to do with anything that was previously talked about. Or as Christopher says "Very funny guys cutting that video". Maybe it is an inside joke that only certain people involved in the doc will get, and when those people saw it they pi$$ed themselves laughing. Whatever it is (unless by some unlikely chance someone comes on TDF watches the doc and happens to know someone involved in it) I seriously doubt we will ever know. No matter it is still pretty damned funny.

  31. Søren Dahse

    they claim to know everything, but they dont. only a kid would fall for their overly simple explanations, or i guess its not just kids. how sad.

  32. Furqan Han

    After having watched this documentary, I understood, that these scientists have found absolutely nothing. I mean, all they do is assuming things and composing some fancy theories withough proving anything but beside that, they talk in such a sure manner as if they have found all answers. In every sentence they contradict themselves again and again. I'm no scientist, but if you would let me do the talking, I could speak about these things as well, looking like a scientist. But then again, it' would be just a man made story. One thing is for sure: it is entertaining!

  33. Achems_Razor

    I suppose then by your man-made expose that you would also include all the man-made gunk of all the religions right? Presume that is where you were leading to?

    By the way give back the man-made computer you are writing on, because it definitely is science, and you do not believe in that! Since it was assumed by the scientific method by fancy theories.

  34. Teddy Mcd

    @Greg_Mc , @Christopher Fox, @Alex Kilpatrick, et al...

    The bike going backwards at 26:55 of the first vid. My guess is that the background was edited in later (she's not sitting outside) and the editor inserted/spliced it in reversed or backwards. Just like running an old school 8mm film backwards.

    Great doc - thanks.

  35. Greg_Mc

    Hmm just tried to watch it again to show my son and at 26:55 they are talking about mulitple universes and showing something to do with space. I do not see the bike dude anymore, do I have the time wrong? It was 3 months ago when I last (first) saw it so I do not remember the exact time, I do remember it happened on a street and not in space lol or maybe it did happen in space but I was in another universe 3 months ago where the street was actually space and space was the street. Or just maybe I shouldn't have done so many drugs when I was younger lol.

  36. Teddy Mcd

    The bike going backwards at 26:55 of the first vid. My guess is that the background was edited in later (she's not sitting outside) and the editor inserted/spliced it in reversed or backwards. Just like running an old school 8mm film backwards.

  37. oQ

    I agree with you....one can only make an objective opinion of the series by watching the whole series. I watched them in the opposite order by curiosity.

  38. Michael

    eternal life amen

  39. Rampage

    3 years ago wow :)
    Also I disagree, I would assert that a belief in a God is arrogant and for many reasons. Here are just two -first, pretend for a moment there is a God(which wont be hard for you), which is based on one of the many religions. Well, who says your religion is right, chances are you are wrong. What if your right though in either case the other 95% are going to burn in hell, or lets say instead 2% burn in hell instead just to give you the benefit of the doubt for a moment. People are being tortured for eternity for something they did in a confusing chaotic senseless finite life? Including the disbelief in some ancient man-made contradicting book of fables.

    Another reason is the fact there is no testable proof, and the faulty untested personal experiences many of which can easily be disputed as wishful thinking or any various forms of hallucinations don't count. We live in a world where we can test things and interact with things. If not then we don't care about them period they as far as we should be concerned are non existent or at the most not influencing our universe; regardless if they are true. Now the moment this becomes false, and I have some convening proof which will justify any such claim I will start exercising what it may mean to have a creator, But I assure you there is no God according to any of the ancient faulty religions, God if there is one is the deist God, and he is probably the Pantheist God or the universe/ multiverse(I'm not sure if i am OK with this term..) itself. And you have no right to take that away from it by putting some ridiculous book of stories on it that should have been dropped when people started to think maybe around Newton's time? Now When I say "it" I mean the universe whether or not that means its conscious is not to be interpreted what is to be interpreted is I have zero clue and I take the logical positivists view to it all, and that is its a stupid debate as much as I love to participate in it, it is meaningless until there is evidence. Therefore you lose. I wont expect a reply but I would like to see one.

  40. Janeen Clark

    the name is what we still don't know, how is that assuming things and contradicting? there asking questions this series is the best out there sometimes you have to think outside the box to find a new solution to a problem that is the purpose of this series.

  41. Janeen Clark

    this series is the best there is! i first watched it in 2006 and have seen it probably 90 times all together luv it

  42. Glenn Daniels

    there are scenes throughout, that resemble something out of "Alice in Wonderland" with checkerboard patterns in interesting, almost optical illusion type landscapes ... does anyone know where that was filmed? seems like it would be some sort of "post modern art" park, or museum. thanks

  43. Glenn Daniels

    the locations with all the checkerboard back-rounds, anybody know where they are / where those sections were filmed?

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