The universe is incredibly old, astoundingly vast and populated by trillions of planets — so where are all the aliens? Astronomer Stephen Webb has an explanation: we're alone in the universe. In a mind-expanding talk, he spells out the remarkable barriers a planet would need to clear in order to host an extraterrestrial civilization — and makes a case for the beauty of our potential cosmic loneliness. "The silence of the universe is shouting, 'We're the creatures who got lucky,'" Webb says.
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first comment , by the way nice ted talk
What if we are the aliens amongst ourselves… the people before humans might’ve owned this planet before us so they come back to make sure we aren’t destroying it which we kinda are with greenhouse gasses etc
Isaiah we couldn’t be the aliens because we coined the term for ourselves, created the entire idea of aliens outside of this world, and also “alien” is a relative term.
We are all aliens.
Proxima and trappist have flares
Humans are terran monkeys. You are no more aliens than chimps are.
There was a video from Issac Arthur about this idea, but the general gist is that it doesn’t affect anything and returns back to the paradox, where are the original aliens? Surely they had some escape methods.
If you want a much more comprehensive answer than this I would suggest you watch Isaac Arthur’s Great Filter series of videos here on YouTube.
He goes into great detail and has a much more developed answer to many of these questions.
THX
Looks like a good watch, cheers!
Sam Fanthorpe
Not just those specific videos, his entire channel would be incredibly interesting to anybody remotely intrigued by the idea of this TED talk.
+Pseudonymous Being Agreed. Its one of the better channels regarding these kind of subjects on youtube honestly.
Isaacs channel is great!
trumps space force will deliver intergalactic diplomacy with an iron fist!
Or…just more debt
Yup, more debt.
Yes, the chances of multi-cellular life capable of technology, self awareness, curiosity, creativity and exploration is pretty ludicrous.
Chris Stanford, yet here we are.
anEnigma So I assume you also spend money on the lottery?
Remember that big numbers are on both sides of that math 🙂
Fabian Leopold, well it seems I have pretty good luck, seeing how I defeated billions of other sperm to be alive on the “only” life sustaining planet in the universe.
Who knows?
Justin Y. You need to get a job or drop dead from cancer of the eyes
Blinky Pinky Inky and Clyde that’s fricken rude! I do know he is a bot or whatever, *BUT WHAT HAS HAPPENED TO HUMANITY?*
Oh gosh… not you
Bella Sherwin I am the well spring from whence you flow. Without me, you will have never been..
+Blinky Pinky Inky and Clyde did.. did you plagiarize Shakespeare? •~•
im so fuggen high
CedrikAberle IDIOT!
TenaciousC Hypocrite!
Alex Greist , your mom goes to college….
he made me realize and appreciate how lucky we are to be on this planet.
…given that we can be apart from our bodies.
I never understood this way of thinking. It is like… we were floating in space waiting for a planet and human bodies to form and then being able to occupy them. Well, sure THAT would be a tremendous amount of luck. Seeing how unlikely the series of events is.
BUT if we are a result of this planet that means these series of events can only be observed if they already happened, then the chances of this observation is a 100%. Otherwise you could say “The Martians are unlucky” totally ignoring the fact there are none. There is nobody to be unlucky in this regards. It seems strange to me. 🙂
But nothing wrong with appreciating the planet, and taking care about life. Would be a shame if it disappeared again.
morn1415. Well said. I was thinking something similar.
morn1415 I left my body I thought it was amazing that I managed to get back to it.
Even if there was a spacefaring civilization the way I like to imagine or describe the problem of contact with an alien species is to imagine every planet in the galaxy being a grain of sand on a beach, and one of those grains of sand is blue and that’s Earth, and then you take a few wooden planks each one represents a spacefaring civilization, you then drop those wooden planks on to the beach at random, now each wooden plank is going to be touching dozens if not hundreds of grains of sand, which represents touching hundreds of planets with their space travel, but the chances of those planks touching that one blue Speck of sand is still incredibly small.
It’s not just space, but also time. We could go extinct at any time. So you could have approx. 100 grains of sand turn blue at random times, but they’re only blue for 10 minutes. The odds of making contact are not just whether the stick touches two blue grains, but also whether an snail crawling along the stick encounters two grains that are blue at the exact moment he passes.
(I don’t know why there’s a snail on a sandy beach.)
Good analogy. Wouldn’t you say though, that as the blue spec we could still look out and see the wood if we tried hard enough? I mean we have a much better chance at see the wood then it does of see us
This guy:
> Sees strange UFO – 00:13
> Doesn’t believe they’re here – 11:53
This is the reason most people don’t bother researching this subject. This extreme level of disbelief of what one *has already seen* stems from the lack of persistent stimuli to the brain. Any psychologist or neurologist should know this.
For instance, if there is persistent stimuli to the brain, over time it causes neural structures to become strengthened as they are activated more often. These neurons are prioritised. It’s how we “learn”. [Extreme oversimplification, but you get the point.]
If neurons are stimulated by a one-off experience, these neural structures start to degrade over time and are considered low priority by the brain, as the brain decides to prioritise strengthened neural structures that have been activated more often by external stimuli.
This is how we decide what is “real” and “not real”. It’s a shame most people haven’t learned to overcome this bias yet.
alex seioo
I’ve seen things to know there are objects flying in the sky that defy belief. I’m an amateur astronomer – I have spent a lot of time outside with the telescope.
It all depends on the individual too. There was a UFO reported to be in close proximity to Jodrell Bank radio telescope a few miles from where I live. Someone called them and told them it was there. They didn’t believe him even though he asked them to look outside. They stayed inside, thinking it must’ve been prank call.
People’s attitudes towards the phenomenon differ due to either experience or lack of experience with it. The cognitive bias I mentioned above also skews experiencer’s minds into giving their experience a low priority, so they stop thinking about it. After all, the human brain is tuned for survival, not critical thought.
+Jim Griffiths what are you talking about?
he didn’t become biased, he just was reasonable ;
He’s biased due to the way the neurons work in his brain. I went into it in the first comment.
Basically, transient stimuli is classified by the brain as being “not real”; persistent stimuli is classified as being “real. This is a form of cognitive bias.
The state of something being true or false is separate from the process by which the brain stores information.
So, when the brain perceives transient stimuli as being “not real”, it is more likely that the brain is falsely classifying a real experience as being not real due to the way in which it operates at the physical level. Because the stimuli was only experienced once and has never occurred again, the brain is deluded into thinking “it must not be real.”
The obverse is also true, where the brain falsely classifies something as being “real” simply because someone or something has repeated the same message over and over. Mainstream media exploits this and literally hacks people’s brains. They repeat things from different news sources verbatim which programs neural structures in people’s brains to have priority over other neural structures. They then have the false perception that something is “real” when it may not be.
This speaker is biased and it’s obvious. Compare: 00:13 and 11:53.
He is suffering from cognitive dissonance and resolving it through ignorance of his experience, because he’s falling into the bias of: Falsely putting a low priority on a transient experience while prioritising persistent experiences. Don’t know how else to put it.
Where are they? Certainly, they are here among other places, presumably. Very credible witnesses including US astronauts, pilots, et al., attest to viewing UFOs and other intelligent extraterrestrial phenomena.
http://www.disclosureproject.org/
What you believe to be real is not a standard of evidence transferable to others – no matter how tangible it is to you. Your evidence has to be transferable and remove all reasonable doubt. Your statement opens the door to vast subjectivity and hearsay as the standard of evidence for reality.
Yes lets keep believing we are the center of the universe. Of course aliens would want to associate with beings that are not capable of space craft. I regularly go to the zoo to watch monkeys I try talking to them, but they just don’t seem to understand me. I guess they simply can’t talk my language yet. Why would i not go ahead and jump into the cage with the apes. Oh earth is so special that any aliens would want to live here and be around us. I am getting sick of this blind arrogance. As for physics I think it is more about what they don’t know then what they are actually are certain about. Not to mention the vast area of space that we still can’t even truly conceive of traveling from one habitable planet then to another.
First of all, aliens are not humans (Modern humans at the very least), they may very well be like us, but they are a completely (I assume) different species, who can say that they would want to interact with lower beings? Let’s say they were like us. Humans don’t interact with ants, we may play with them, study them, and then what? Ignore them. (Zoos too, but that’s a whole ‘nother topic)
I could go on, but I’m tired, so go watch Issac Arthur’s series on the Fermi Paradox if you want to know more/idk.
If u are well educated like scientists , you would have your awareness at maximum sort to speak. If you are aware of ants in front of you, you will not step on them. If you are educated as soldier, you crush everything until you achieve your goal of stupidity. We would be already dead.
You cannot talk like that about us yet, because we are still savages.
its not a question of whether they would be inclined to communicate with us… if they are out there, we should be seeing signs of it. We should be finding anomalies, stars behaving weirdly with no natural explanation, bizarre signals in the infrared – but we see nothing, at all, anywhere
When we look, we look in the past. And we cannot see far enough. The way we look doesn’t make any sense.
Right now humans are clueless. It could be that advanced species use physics way beyond general relativity and quantum mechanics and live in other dimensions. Maybe advanced species become immortal, stop reproducing and live humbly on their planet. Maybe we are a experiment of the rulers of the milky way. Maybe we are a simulation like the TED guy said. Maybe there is a god who created the universe and laws of physics and designed it in a way so that we were alone.
I hope we figure it out by the end of my life. Even if it means an evil alien civilization will enslave us. I will be old so I wont care. I will be happy that the mystery is solved.
Oh wow…. beautifully presented. The ending argument was poetic!
What if aliens already have been here the whole time, just in disguise as humans and they’re so advanced that we couldn’t even tell
The real Neil deGrasse Tyson died 15 to 20 years ago
Why would they stay hided? Instead of taking advantage of their superiority? I think it has no sense. They are not in earth at the moment in my opinion. Maybe in one of the trillion planets, but not here, we’re the unique aliens in earth.
Hans DG I don’t know so maybe they could study us or even control us just anything
Hans DG
Why wouldn’t they stay hidden?
I imagine it would be like Star Trek
Prime Directive or something…
I mean, if such ^a thing(^s…?¿?) were true, they’d most likely be able to dominate the entire planet, but maybe have no interest in it.
Perhaps intelligent life is precious enough to be interesting…
Maybe we taste better if we’re not scared.
We have the universe all to ourselves? I got dibs on Alpha Centauri!!
kash krupa lol
You have a be a braindead christcuck to think this entire universe was made just for us.
lol christcuck
The universe wasn’t created for us, we came into being because there’s a whole uninhabited universe for the taking.
Or it’s like in the Star Trek movie that they are not allowed to interfere with us until we are more developed. Not to mention all the ufo sightings so maybe they are already here and they have a deal with the government.
That’s possible, but unlikely.
Why?
This planet will be UNLIVABLE in about 15 years because of Climate Change.
Unless aliens *want this to happen* , I believe that they would intervene to stop it.
Atheist7
Its a test is what theyll say. What if this what if that. Its all baseless wishful thinking, no better than religion this speculation is. And in any case highly ignorant of scientific fact and posted by youngsters enamoured by HALO or fantasy.
Pseudonymous Being well scientific fact is that there are hundreds of billions of stars in our galaxy and hundreds of billions of galaxies in our universe. To say none of them have no form of life is just ignorant. Especially the fact that they just found liquid water on mars which is just in our solar system. So out of 8 planets in our solar system at least 2 have liquid water which increases the chance of life ten fold. These are some pretty good odds of life elsewhere in the universe
For a fermi paradox (the contradiction of the size of the universe, and the lack of aliens) explanation, it needs to be applicable to all potential civilisations. If a non interference policy was the explanation, all of the individuals that could contact us in all the different alien civilisations, would need to agree and adhere to that policy. How likely is that? that all civilisations and all of their members decide to not contact us? Extrapolating from human behaviour, how well does that go? Does poaching stop in national parks, do national parks receive no visitors? No, we interact with the fauna and flora of national parks, wether governments want it or not, why should it be different for extraterrestrials?
As for your second idea that the government has a deal with extraterrestrials to hush it up, what incentive would the extra terrestrials have to hush up the governments, of pathetically weak civilisation? Plus how difficult is it to hush this kind of thing up in modern democracies?
No, the solution that fits the paradox is that alien civilisations are incredibly rare, or get destroyed before becoming detectable.
To say that we have not been contacted by aliens is fine. But to say that because we have not been contacted by aliens means there are no aliens is just stupid. And I was kind of going overboard with my original comment but to entertain the thought. Who knows what sort of deal aliens could make with the government? Say if there were aliens that ate humans would they kill us all at once or let us be herded like animals able to reproduce freely and populate the planet giving them a never ending food source. Same reason we herd cattle rather then exterminate them. Another sci-fi like idea would be the question on what would the best option be for colonizing the galaxy. I think it would be much easier for aliens to slowly work from inside human society slowly getting humans ready for alien contact rather then a full scale alien invasion like the movie. This is why we have unlimited conspiracies about the government hiding aliens ect. And don’t think that I believe everything I am saying these are just ideas…
I hope we aren’t completely alone, it’d be such a disappointment if we’re the best the universe is capable of making seeing what a cancer we are to the only planet that would be capable of life.
What makes you think they’re not worse?
And I work at a charity and resent being called a cancer.
Charles Dickens I mean they could be worse if they exist. There’s plenty if scenarios were that’s possible. But going off what we know currently we are undoubtedly the worst species to exist as a whole. We as a species might have tipped climate change to an irreversible level and screwed the entire planet. Of course some people are trying to help but that small percentage is not enough. As long as we cut down forests, use cars, use harmful energy sources and pollute our oceans we are a cancer this planet would be better off without.
You’re way way overestimating the destructive capabilities of humans. We are absolutely nothing to the planet, we could nuke the entire thing in a suicide attack and within a few hundred years it would be back to its natural state.
Random Gentleman Not quite.
Aliens: “oh, there is life on that blue planet” … “oh, it’s underdeveloped” … “boooring!” … “let’s drive by” 🙂
I’m an alien.
One thing I find interesting is the big emphasis on Goldilocks zones and planets and the building blocks of life. While that’s how our specific known life forms function we have to remember it’s just that, life as WE know it. There is a huge possibility that there are many other substantial forms of life are created with different building blocks (maybe even elements we haven’t discovered or don’t exist on our planet or even our galaxy) or lifeforms who can survive in different environments than us with opposing “Goldilocks” conditions for their species. We tend to write-off the ideas of other complex life as impossible solely based on our knowledge of how our current known life works with our observed personalised scientific data of this planet’s organisms and physics. But without being in contact with other life forms from different planets/solar systems/galaxies we really don’t know how their biology or planetary systems work and I don’t think we can compare it to our own to try and find out.
But then again that’s just my own thoughts and opinions on the matter.
Well pretty much the whole point of science is writing off stuff you don’t have evidence for. If you don’t assume that what you ‘know’ is correct then you might as well not believe in anything since everything we ‘know’ is based on evidence.