10 ms·

Stephen Hawking on time travel, M-theory, and extra terrestrial life

121 points by zoowar 14y ago

vibrunazo 14y ago
I love Hawking. But unfortunately, this interview is too short, simple and obvious to be interesting. Reminds me of: http://xkcd.com/799/ http://xkcd.com/799/
cletus 14y ago
The odd thing about the universe seems to be that the distances are so vast that it almost doesn't matter if there's other sentient life here or not because it's far too distant to be of any relevance. Travelling between stars is incredibly expensive (in terms of pure Joules) and time-consuming. I can see the logic in the theory that the most likely outcome for any species reaching sentience is to destroy themselves. either through direct means (eg nuclear or biological war) or indirectly (simply running out of resources)
- Fizzer 14y ago
  Calling it irrelevant just because you can't travel there is short-sighted. We could still learn a lot just by watching the broadcasts of another civilization, even if they're already long gone.
  - rewind 14y ago
    And just knowing they exist would be incredibly exciting, even if there was zero chance that we could directly contact them in the span of our entire existence.
  - snowwrestler 14y ago
    The distances are so great that the broadcasts of another civilization would attenuate to undetectable levels before they could reach us.
  - vibrunazo 14y ago
    Out of all infinite amount of different methods to communicate and broadcast themselves they could possibly be using. Including the ones we didn't even discover yet. Assuming they're using the same ones humans just found out in recent history. The ones SETI is measuring. Even then, assuming it's formatted in a way we would decipher and be able to understand its structure (as in Carl Sagan's movie). That just sounds so improbable. Even if they are broadcasting it, we're probably listening to it with the wrong technology. Even if we happen to be lucky of listening with the "right" technology. We probably wouldn't be able to tell it from random noise. I find it extremely unlikely humans will ever be able to watch alien broadcasts during our existence in the universe.
    - dexter313 14y ago
      "Even if they are broadcasting it, we're probably listening to it with the wrong technology. Even if we happen to be lucky of listening with the "right" technology. We probably wouldn't be able to tell it from random noise." That's why you start by blasting prime numbers on all em frequencies for 5 years.
    - lusr 14y ago
      I don't think there are many different ways to encode meaningful information. We all live in the same universe and I see no reason to believe that intelligent alien life won't be intellectually quite similar to us. While tricky without context, decoding extraterrestrial signals will inevitably produce something of interest (images, audio) even if understanding e.g. the audio itself will be tricky. That being said, while I suspect that meaningful, structured information will be, by definition, structured and therefore obvious to spot in a broadcast, the real problem is that these transmissions are likely to be (a) compressed and/or (b) encrypted. While compression formats may reveal a few hints that there is some structured information present, encrypted data will be all but impossible to distinguish from random transmissions. We may be picking up transmissions from alien life but be unaware simply because the data is encrypted. I have no idea what proportion of our broadcast signals are encrypted today, but I suspect it's a fairly significant and growing proportion (privacy and intellectual property concerns being the primary reasons).
  - ygmelnikova 14y ago
    What lessons are to be learned from the alien version of "I Love Lucy"?
- tlogan 14y ago
  The super intelligent life will live forever so distance/time might not be relavant to them as it is to us. Also, it seems like at this stage of our intelligence we can communicate and find only intelligent life which is at similar stage (which is maybe span of 100K +/- 10K years). That is nothing.
- bane 14y ago
  It's kind of like an old joke from Penny Arcade, once something gets too expensive to be practical it may as well cost infinity. http://www.penny-arcade.com/2008/12/1/ http://www.penny-arcade.com/2008/12/1/ Mathematically inaccurate but can be a short and simple way of summarizing costs and complexity.
- anonymous 14y ago
  Could we travel by moving the entire solar system with us? Build a dyson sphere around the sun and harness part of the energy to ever so slowly move our planet and sun towards a nearby suitable star system. Then settle our planet in orbit around the other star. This way we should have at least some way of sustaining human life past the end of our sun.
- caf 14y ago
  The distances are indeed vast, but the time periods involved are yet more vast. A Von Neumann probe travelling at quite modest speeds should be able to spread over our entire galaxy in mere millions of years; the universe is billions of years old. So while direct visitation by aliens seems highly improbable, such a probe making contact seems at least a theoretically plausible possibility.
Xcelerate 14y ago
I've been watching his "Into the Universe" series, and honestly I have been a bit disappointed. I was hoping for more science -- details about subatomic particles, a discussion of the various interpretations of quantum mechanics, an introduction to M-theory (that doesn't involve violins and floating colors). Instead, one whole episode was devoted to ragging on religion -- a bunch of speculation that doesn't teach any of the interesting science to the show's viewers. How about an introduction to Hawking radiation, the holographic principle, superpartners? At least an overview of the standard model? Nope. Just reasons "God isn't necessary". I'm not sure why he takes this route for the show. Maybe it gets more viewers and more controversy. It's sadly reminiscient of the history channel. It used to be full of a lot of interesting, objective content about -- believe it or not -- history, but now it's just full of alien speculation and religious prophecies.
- rewind 14y ago
  It's not a show about science; it's a show about ratings. Popular science gets ratings, which are still less than non-popular-related shows, and which are far higher than any hard-science-related shows could ever get. You'll have to scratch that itch somewhere else... though I totally agree with you!!!
- tdfx 14y ago
  I used to watch the History Channel all the time. I'd keep it on throughout the day while I worked, always enjoying war documentaries or historical pieces. Now it's all reality TV and "Who would win in a fight: Navy SEAL vs. Samurai" nonsense. I guess the "watching television to be informed" target audience is dwindling faster than I thought.
hobin 14y ago
I don't really see how this is news. Don't get me wrong, I think Stephen Hawking is a very smart man, and he has definitely done his fair share of work to help people understand science - not to mention that his scientific accomplishments aren't bad, either. That being said, there's just nothing new in this Q&A that he hasn't already said or wasn't already widely known to anyone who bothered to do a quick search on Google (except perhaps the part about his quality of life, but let's face it, that's not important).
- pvarangot 14y ago
  I don't think the part about his quality of life is not important. Lots of people have disabilities, only accounting for spina bifida which is physically less disabling that ALS, or muscle atrophy which leaves cognitive capacity intact, already puts them in the thousands. Someone needs to show them they can achieve many of what they dream about, because most of society only gives them pity and consent. We have Olympic Games for disabled people whose dreams are of being athletes, and we need people like Stephen Hawking to show disabled wannabe scientists and hackers (many of whom I believe read HN and ars) that they can also triumph in their geeky endeavours.
  - hobin 14y ago
    You raise a valid point. If that were the case, though, then I would argue the article should've been posted under a different title. The current title suggests that I'm going to see mr. Hawking say something profoud about time travel, M-theory and extraterrestials.
- BlackNapoleon 14y ago
  Thats just it though. There are many who WONT go back and re-read what he has said. Some people think that by virtue of him having something to say that he's presenting something new. You have to remember that in knowing and being familiar with the content being presented that you're in the minority of people who will EVER grasp this knowledge, even on a basic level. Its important for more people to learn about the frontier in as many ways as possible, as often as they can.
jpeg_hero 14y ago
Pithy.
Variance 14y ago
I'd say that the chances of us ever coming into contact with intelligent life are worryingly low until well (as in, billions of years) into the future. If we say that "ultimate maturity" of a civilization is to have a technological singularity of some sort, resources wouldn't really be an issue. SETI hasn't picked up anything. Assuming that the universe is infinite in extent, as it currently is hypothesized to be, the only real solution is that life is so spread out as to be almost irrelevantly far away.
- rimantas 14y ago
  We don't have billions of years. We maybe have one billion.
ChrisNorstrom 14y ago
We will NEVER be visited by extra terrestrial life. The amount of luck required is too great. It's extremely unrealistic and foolish. 1) We need to come to the realization that it is and always will be impossible to travel at the speed of light or anywhere near the speed of light. Doing so would cause radiation particles, micro particles, space dust, and other little things floating around to hit the the crew and ship at extreme speeds and rip the ship apart. A bullet fired from a high powered rifle is only going 1,200 mph and can rip through metal. So imaging your space ship getting pummeled by particles at 670,616,629 mph and the faster you go the more particles you got bombarded with. There are no metals or materials that can sustain this type of damage because these radiation particles are SMALLER than x-ray particles so they'll pass through absolutely everything. And nothing can filter out or block this astronomical amount of radiation that will pummel the crew. We can wish and hope but it's a problem that is out of our control. 2) We need to stop falsely and foolishing assuming that there are aliens far out in the universe that can see us (2012) through a telescope. If you look at the earth right now (2012) from 65 million light years away, to the extra terrestrial, they are just now seeing light from 65 million years ago reach them. So to them there is no intelligent life on earth yet. It won't be another 65 million years until they are finally able to see us humans. By that time WE or THEY will be extinct. Because WE have the same problems THEY have. The vast majority of planets or uninhabitable and we can't travel fast enough to reach a planet, nor evolve or adapt to the bacteria on that planet fast enough to actually live on it. 3) We will most certainly never be able to "move homes" to another planet because the bacteria and organisms on it would be hostile to the point where we can't even safely evolve around it. We can live on Earth because for millions of years our ancesters have built up immunities to all the nasty viruses and plagues and flus that have come and gone. If an extra terrestrial landed here on earth they would not be able to interact with us in ANY way without wearing a bio-suit. They can't breathe our air or drink our water. And you think they're going to travel millions of years to get to a planet they can't even vacation on or enjoy or interact with in any way. 4) Extra terrestrial life that is more advanced than us has no reason to go on a suicide mission to come see us (a bunch of war-mongering primitive hairless baboons) To any potential aliens who are living millions of years away, we haven't even evolved yet. By the time they see us, we will be gone. By the time they travel millions of light years to finally reach us, both of our species will be dead. Us from extinction and them from getting blasted by radiation. Also, if they are more advanced than us why the hell would they want to come all this way to see us?! That would be like us traveling millions of years on a suicide mission to go see a planet of lemurs.
fferen 14y ago
Here's an idea that's been kicking around in my mind for a while: what if it's not that it takes such a tremendous amount of time to travel anywhere interesting in the universe, but that our perception of time is just too fast? Perhaps to an alien race a thousand (or million) years seems like a second. Wikipedia suggests that our perception of time does get (slightly) slower as we age [1], so maybe living significantly longer could do this to us as well. Finally, it seems that our perception of time is largely shaped by the Circadian rhythm; if life evolved somewhere with a much slower "cosmic clock" could that also cause a much slower time perception? [1]: http://en.wikipedia.org/wiki/Time_perception#Long-term http://en.wikipedia.org/wiki/Time_perception#Long-term
- dr42 14y ago
  While our perception of time night be subjective, as you suggest, the distances involved are not. Even if it only feels like a few moments, the universe doesn't much care how we feel, or what we perceive.
  - fferen 14y ago
    Well, yes, obviously, but it would certainly affect how we (read: aliens) approach space travel psychologically, and thus to a certain extent its feasibility - a trip across the solar system could seem like a trip across the street.
nothacker 14y ago
I've come to believe that the reason Hawking says what he does is because he knows being controversial and having an intelligent argument for your view, whether it is right or wrong, sells books, T.V. shows, interviews, and gets you money. I also think that he thinks he's all that. Einstein was not such a dick.
verroq 14y ago
Is it possible that in another universe, time travel is possible and Steven Hawking had the most awesome party imaginable?
mbenjaminsmith 14y ago
I'm surprised to hear someone of his intellectual caliber resort to ridicule when someone brings up UFOs. UFOs "appearing" to "cranks and weirdos" doesn't really describe the phenomena, as anyone who spent more than 30 minutes on the subject would know. I'd would have loved to have heard him debate the late John Mack (Harvard Medical School, won a Pulitzer) on the subject. It's incredibly arrogant for him to think that he can ignore the research of other academics (or remain in ignorance of it) and still speak authoritatively on the subject. I don't expect him to champion the field but since he's asked so frequently about extraterrestrial life and/or UFOs it would be nice if his canned response was a bit more intelligent. It's incredible to dismiss so much theoretical/speculative physics in the interview and at the same time say that maybe M-Theory will tie up the loose ends in the Standard Model, but then again, maybe it won't and we'll be back to the drawing board. Even though we admittedly don't understand the universe with any degrees of completeness, obviously these popular ideas are false based on our understanding of the universe?
- rimantas 14y ago
  > doesn't really describe the phenomena, as anyone who > spent more than 30 minutes on the subject would know. It actually does.
  - philhippus 14y ago
    There are plenty of credible witnesses to UFO sightings. The problem is people getting their knickers in a twist over the acronym 'UFO' - a product of societal conditioning.
huhtenberg 14y ago
> I have experimental evidence that time travel is not possible. I gave a party for time-travelers, but I didn't send out the invitations until after the party. I sat there a long time, but no one came. Why would one need to send invitations if the outcome is already known once the party is over? It seems that merely giving a party for time-travelers is a plenty sufficient evidence. > Another frightening possibility is intelligent life is not only common, but that it destroys itself when it reaches a stage of advanced technology. Or that it transcends beyond physical 3D realm (as corny as it sounds) and so it's no longer detectable from within it.
- CJefferson 14y ago
  > Why would one need to send invitations if the outcome is already known once the party is over? Well, if you didn't invite anyone, maybe the reason no time-travellers came is that they weren't invited?
DrewChambersDC 14y ago
Lets be honest, there's obviously other intelligent life in the universe. There's probably tons of it, I don't think it's ever visited earth before, and we'll likely never shake its hand, but its out there. One day we can hopefully communicate with one, it would have to be done with radio signals over generations, but it would be amazing to see it happen. I've always thought it more likely than the fact that intelligent civilizations destroy themselves is the fact that intelligent civilizations are out there and the really smart ones actually know the Earth exists. Interstellar distance is likely a problem that no one has truly solved but I like to think there's civilization out there that knows the Earth exists and is ripe for life, just they're too far away to do anything about it.
- rimantas 14y ago
  Obviously? Like I go outside and there it is— obvious non-terrestrial intelligent life? For me it obviously does not exist. It may exist somewhere in the galaxy far away. It might not. We don't know. We will never (by never I mean ~1 billion years) know. I am amazed to see so much wishful thinking and ignorance regarding physics and astrophysics.
elorant 14y ago
Everyone interested in the possibility of alien intelligence should read about the Fermi Paradox: http://en.wikipedia.org/wiki/Fermi_paradox http://en.wikipedia.org/wiki/Fermi_paradox It is a collection of theories that try to explain why we haven't been contacted yet by aliens. There is also a very good book on the subject that elaborates further on the theories of the Fermi paradox. In total there are 50 different theories, from life been too young on the universe and thus we're rather alone, to not be able to communicate because they're using superior technology. http://www.amazon.com/Universe-Aliens-Everybody-Solutions-Extraterrestrial/dp/0387955011 http://www.amazon.com/Universe-Aliens-Everybody-Solutions-Ex...
olalonde 14y ago
This comment seriously made me laugh out loud: Maybe they like a higher CO2 level and warmer temperatures, and are masquerading as energy company executives. Alienforming a planet is easy if you can get the natives to do it for you.

121 points by zoowar 14y ago

I love Hawking. But unfortunately, this interview is too short, simple and obvious to be interesting. Reminds me of: http://xkcd.com/799/ http://xkcd.com/799/

cletus 14y ago

The odd thing about the universe seems to be that the distances are so vast that it almost doesn't matter if there's other sentient life here or not because it's far too distant to be of any relevance. Travelling between stars is incredibly expensive (in terms of pure Joules) and time-consuming. I can see the logic in the theory that the most likely outcome for any species reaching sentience is to destroy themselves. either through direct means (eg nuclear or biological war) or indirectly (simply running out of resources)

Fizzer 14y ago
Calling it irrelevant just because you can't travel there is short-sighted. We could still learn a lot just by watching the broadcasts of another civilization, even if they're already long gone.
- rewind 14y ago
  And just knowing they exist would be incredibly exciting, even if there was zero chance that we could directly contact them in the span of our entire existence.
- snowwrestler 14y ago
  The distances are so great that the broadcasts of another civilization would attenuate to undetectable levels before they could reach us.
- vibrunazo 14y ago
  Out of all infinite amount of different methods to communicate and broadcast themselves they could possibly be using. Including the ones we didn't even discover yet. Assuming they're using the same ones humans just found out in recent history. The ones SETI is measuring. Even then, assuming it's formatted in a way we would decipher and be able to understand its structure (as in Carl Sagan's movie). That just sounds so improbable. Even if they are broadcasting it, we're probably listening to it with the wrong technology. Even if we happen to be lucky of listening with the "right" technology. We probably wouldn't be able to tell it from random noise. I find it extremely unlikely humans will ever be able to watch alien broadcasts during our existence in the universe.
  - dexter313 14y ago
    "Even if they are broadcasting it, we're probably listening to it with the wrong technology. Even if we happen to be lucky of listening with the "right" technology. We probably wouldn't be able to tell it from random noise." That's why you start by blasting prime numbers on all em frequencies for 5 years.
  - lusr 14y ago
    I don't think there are many different ways to encode meaningful information. We all live in the same universe and I see no reason to believe that intelligent alien life won't be intellectually quite similar to us. While tricky without context, decoding extraterrestrial signals will inevitably produce something of interest (images, audio) even if understanding e.g. the audio itself will be tricky. That being said, while I suspect that meaningful, structured information will be, by definition, structured and therefore obvious to spot in a broadcast, the real problem is that these transmissions are likely to be (a) compressed and/or (b) encrypted. While compression formats may reveal a few hints that there is some structured information present, encrypted data will be all but impossible to distinguish from random transmissions. We may be picking up transmissions from alien life but be unaware simply because the data is encrypted. I have no idea what proportion of our broadcast signals are encrypted today, but I suspect it's a fairly significant and growing proportion (privacy and intellectual property concerns being the primary reasons).
- ygmelnikova 14y ago
  What lessons are to be learned from the alien version of "I Love Lucy"?
tlogan 14y ago
The super intelligent life will live forever so distance/time might not be relavant to them as it is to us. Also, it seems like at this stage of our intelligence we can communicate and find only intelligent life which is at similar stage (which is maybe span of 100K +/- 10K years). That is nothing.
bane 14y ago
It's kind of like an old joke from Penny Arcade, once something gets too expensive to be practical it may as well cost infinity. http://www.penny-arcade.com/2008/12/1/ http://www.penny-arcade.com/2008/12/1/ Mathematically inaccurate but can be a short and simple way of summarizing costs and complexity.
anonymous 14y ago
Could we travel by moving the entire solar system with us? Build a dyson sphere around the sun and harness part of the energy to ever so slowly move our planet and sun towards a nearby suitable star system. Then settle our planet in orbit around the other star. This way we should have at least some way of sustaining human life past the end of our sun.
caf 14y ago
The distances are indeed vast, but the time periods involved are yet more vast. A Von Neumann probe travelling at quite modest speeds should be able to spread over our entire galaxy in mere millions of years; the universe is billions of years old. So while direct visitation by aliens seems highly improbable, such a probe making contact seems at least a theoretically plausible possibility.

Xcelerate 14y ago

I've been watching his "Into the Universe" series, and honestly I have been a bit disappointed. I was hoping for more science -- details about subatomic particles, a discussion of the various interpretations of quantum mechanics, an introduction to M-theory (that doesn't involve violins and floating colors). Instead, one whole episode was devoted to ragging on religion -- a bunch of speculation that doesn't teach any of the interesting science to the show's viewers. How about an introduction to Hawking radiation, the holographic principle, superpartners? At least an overview of the standard model? Nope. Just reasons "God isn't necessary". I'm not sure why he takes this route for the show. Maybe it gets more viewers and more controversy. It's sadly reminiscient of the history channel. It used to be full of a lot of interesting, objective content about -- believe it or not -- history, but now it's just full of alien speculation and religious prophecies.

rewind 14y ago
It's not a show about science; it's a show about ratings. Popular science gets ratings, which are still less than non-popular-related shows, and which are far higher than any hard-science-related shows could ever get. You'll have to scratch that itch somewhere else... though I totally agree with you!!!
tdfx 14y ago
I used to watch the History Channel all the time. I'd keep it on throughout the day while I worked, always enjoying war documentaries or historical pieces. Now it's all reality TV and "Who would win in a fight: Navy SEAL vs. Samurai" nonsense. I guess the "watching television to be informed" target audience is dwindling faster than I thought.

hobin 14y ago

I don't really see how this is news. Don't get me wrong, I think Stephen Hawking is a very smart man, and he has definitely done his fair share of work to help people understand science - not to mention that his scientific accomplishments aren't bad, either. That being said, there's just nothing new in this Q&A that he hasn't already said or wasn't already widely known to anyone who bothered to do a quick search on Google (except perhaps the part about his quality of life, but let's face it, that's not important).

pvarangot 14y ago
I don't think the part about his quality of life is not important. Lots of people have disabilities, only accounting for spina bifida which is physically less disabling that ALS, or muscle atrophy which leaves cognitive capacity intact, already puts them in the thousands. Someone needs to show them they can achieve many of what they dream about, because most of society only gives them pity and consent. We have Olympic Games for disabled people whose dreams are of being athletes, and we need people like Stephen Hawking to show disabled wannabe scientists and hackers (many of whom I believe read HN and ars) that they can also triumph in their geeky endeavours.
- hobin 14y ago
  You raise a valid point. If that were the case, though, then I would argue the article should've been posted under a different title. The current title suggests that I'm going to see mr. Hawking say something profoud about time travel, M-theory and extraterrestials.
BlackNapoleon 14y ago
Thats just it though. There are many who WONT go back and re-read what he has said. Some people think that by virtue of him having something to say that he's presenting something new. You have to remember that in knowing and being familiar with the content being presented that you're in the minority of people who will EVER grasp this knowledge, even on a basic level. Its important for more people to learn about the frontier in as many ways as possible, as often as they can.

jpeg_hero 14y ago

Pithy.

Variance 14y ago

I'd say that the chances of us ever coming into contact with intelligent life are worryingly low until well (as in, billions of years) into the future. If we say that "ultimate maturity" of a civilization is to have a technological singularity of some sort, resources wouldn't really be an issue. SETI hasn't picked up anything. Assuming that the universe is infinite in extent, as it currently is hypothesized to be, the only real solution is that life is so spread out as to be almost irrelevantly far away.

rimantas 14y ago
We don't have billions of years. We maybe have one billion.

ChrisNorstrom 14y ago

We will NEVER be visited by extra terrestrial life. The amount of luck required is too great. It's extremely unrealistic and foolish. 1) We need to come to the realization that it is and always will be impossible to travel at the speed of light or anywhere near the speed of light. Doing so would cause radiation particles, micro particles, space dust, and other little things floating around to hit the the crew and ship at extreme speeds and rip the ship apart. A bullet fired from a high powered rifle is only going 1,200 mph and can rip through metal. So imaging your space ship getting pummeled by particles at 670,616,629 mph and the faster you go the more particles you got bombarded with. There are no metals or materials that can sustain this type of damage because these radiation particles are SMALLER than x-ray particles so they'll pass through absolutely everything. And nothing can filter out or block this astronomical amount of radiation that will pummel the crew. We can wish and hope but it's a problem that is out of our control. 2) We need to stop falsely and foolishing assuming that there are aliens far out in the universe that can see us (2012) through a telescope. If you look at the earth right now (2012) from 65 million light years away, to the extra terrestrial, they are just now seeing light from 65 million years ago reach them. So to them there is no intelligent life on earth yet. It won't be another 65 million years until they are finally able to see us humans. By that time WE or THEY will be extinct. Because WE have the same problems THEY have. The vast majority of planets or uninhabitable and we can't travel fast enough to reach a planet, nor evolve or adapt to the bacteria on that planet fast enough to actually live on it. 3) We will most certainly never be able to "move homes" to another planet because the bacteria and organisms on it would be hostile to the point where we can't even safely evolve around it. We can live on Earth because for millions of years our ancesters have built up immunities to all the nasty viruses and plagues and flus that have come and gone. If an extra terrestrial landed here on earth they would not be able to interact with us in ANY way without wearing a bio-suit. They can't breathe our air or drink our water. And you think they're going to travel millions of years to get to a planet they can't even vacation on or enjoy or interact with in any way. 4) Extra terrestrial life that is more advanced than us has no reason to go on a suicide mission to come see us (a bunch of war-mongering primitive hairless baboons) To any potential aliens who are living millions of years away, we haven't even evolved yet. By the time they see us, we will be gone. By the time they travel millions of light years to finally reach us, both of our species will be dead. Us from extinction and them from getting blasted by radiation. Also, if they are more advanced than us why the hell would they want to come all this way to see us?! That would be like us traveling millions of years on a suicide mission to go see a planet of lemurs.

fferen 14y ago

Here's an idea that's been kicking around in my mind for a while: what if it's not that it takes such a tremendous amount of time to travel anywhere interesting in the universe, but that our perception of time is just too fast? Perhaps to an alien race a thousand (or million) years seems like a second. Wikipedia suggests that our perception of time does get (slightly) slower as we age [1], so maybe living significantly longer could do this to us as well. Finally, it seems that our perception of time is largely shaped by the Circadian rhythm; if life evolved somewhere with a much slower "cosmic clock" could that also cause a much slower time perception? [1]: http://en.wikipedia.org/wiki/Time_perception#Long-term http://en.wikipedia.org/wiki/Time_perception#Long-term

dr42 14y ago
While our perception of time night be subjective, as you suggest, the distances involved are not. Even if it only feels like a few moments, the universe doesn't much care how we feel, or what we perceive.
- fferen 14y ago
  Well, yes, obviously, but it would certainly affect how we (read: aliens) approach space travel psychologically, and thus to a certain extent its feasibility - a trip across the solar system could seem like a trip across the street.

nothacker 14y ago

I've come to believe that the reason Hawking says what he does is because he knows being controversial and having an intelligent argument for your view, whether it is right or wrong, sells books, T.V. shows, interviews, and gets you money. I also think that he thinks he's all that. Einstein was not such a dick.

verroq 14y ago

Is it possible that in another universe, time travel is possible and Steven Hawking had the most awesome party imaginable?

mbenjaminsmith 14y ago

I'm surprised to hear someone of his intellectual caliber resort to ridicule when someone brings up UFOs. UFOs "appearing" to "cranks and weirdos" doesn't really describe the phenomena, as anyone who spent more than 30 minutes on the subject would know. I'd would have loved to have heard him debate the late John Mack (Harvard Medical School, won a Pulitzer) on the subject. It's incredibly arrogant for him to think that he can ignore the research of other academics (or remain in ignorance of it) and still speak authoritatively on the subject. I don't expect him to champion the field but since he's asked so frequently about extraterrestrial life and/or UFOs it would be nice if his canned response was a bit more intelligent. It's incredible to dismiss so much theoretical/speculative physics in the interview and at the same time say that maybe M-Theory will tie up the loose ends in the Standard Model, but then again, maybe it won't and we'll be back to the drawing board. Even though we admittedly don't understand the universe with any degrees of completeness, obviously these popular ideas are false based on our understanding of the universe?

rimantas 14y ago
> doesn't really describe the phenomena, as anyone who > spent more than 30 minutes on the subject would know. It actually does.
- philhippus 14y ago
  There are plenty of credible witnesses to UFO sightings. The problem is people getting their knickers in a twist over the acronym 'UFO' - a product of societal conditioning.

huhtenberg 14y ago

> I have experimental evidence that time travel is not possible. I gave a party for time-travelers, but I didn't send out the invitations until after the party. I sat there a long time, but no one came. Why would one need to send invitations if the outcome is already known once the party is over? It seems that merely giving a party for time-travelers is a plenty sufficient evidence. > Another frightening possibility is intelligent life is not only common, but that it destroys itself when it reaches a stage of advanced technology. Or that it transcends beyond physical 3D realm (as corny as it sounds) and so it's no longer detectable from within it.

CJefferson 14y ago
> Why would one need to send invitations if the outcome is already known once the party is over? Well, if you didn't invite anyone, maybe the reason no time-travellers came is that they weren't invited?

DrewChambersDC 14y ago

Lets be honest, there's obviously other intelligent life in the universe. There's probably tons of it, I don't think it's ever visited earth before, and we'll likely never shake its hand, but its out there. One day we can hopefully communicate with one, it would have to be done with radio signals over generations, but it would be amazing to see it happen. I've always thought it more likely than the fact that intelligent civilizations destroy themselves is the fact that intelligent civilizations are out there and the really smart ones actually know the Earth exists. Interstellar distance is likely a problem that no one has truly solved but I like to think there's civilization out there that knows the Earth exists and is ripe for life, just they're too far away to do anything about it.

rimantas 14y ago
Obviously? Like I go outside and there it is— obvious non-terrestrial intelligent life? For me it obviously does not exist. It may exist somewhere in the galaxy far away. It might not. We don't know. We will never (by never I mean ~1 billion years) know. I am amazed to see so much wishful thinking and ignorance regarding physics and astrophysics.

elorant 14y ago

Everyone interested in the possibility of alien intelligence should read about the Fermi Paradox: http://en.wikipedia.org/wiki/Fermi_paradox http://en.wikipedia.org/wiki/Fermi_paradox It is a collection of theories that try to explain why we haven't been contacted yet by aliens. There is also a very good book on the subject that elaborates further on the theories of the Fermi paradox. In total there are 50 different theories, from life been too young on the universe and thus we're rather alone, to not be able to communicate because they're using superior technology. http://www.amazon.com/Universe-Aliens-Everybody-Solutions-Extraterrestrial/dp/0387955011 http://www.amazon.com/Universe-Aliens-Everybody-Solutions-Ex...

olalonde 14y ago

This comment seriously made me laugh out loud: Maybe they like a higher CO2 level and warmer temperatures, and are masquerading as energy company executives. Alienforming a planet is easy if you can get the natives to do it for you.