|
|
|||||||
| View Poll Results: Raise or check | |||
| Check |
   
|
7 | 63.64% |
| Raise 200 |
  
|
4 | 36.36% |
| Voters: 11. You may not vote on this poll | |||
 |
|
|
Thread Tools | Display Modes |
|
|
|
#2
12-13-2005, 05:42 PM
|
|||
|
|||
Re: Have aliens visited earth?
id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely.
|
|
#3
12-13-2005, 05:49 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely. [/ QUOTE ] Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. Microbes quite likely exist in abundance but complex life not. This argument was first set forth in the book Rare Earth: Why Complex Life is Uncommon in the Universe by Peter Ward, Donald Brownlee.
|
|
#4
12-13-2005, 05:50 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
[ QUOTE ] id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely. [/ QUOTE ] Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. Microbes quite likely exist in abundance but complex life not. This argument was first set forth in the book Rare Earth: Why Complex Life is Uncommon in the Universe by Peter Ward, Donald Brownlee. [/ QUOTE ] even if its uncommon tho, the incredibly vast number of other stars/planets in the universe means its pretty likely its happened elsewhere.
|
|
#5
12-13-2005, 06:12 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
[ QUOTE ] [ QUOTE ] id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely. [/ QUOTE ] Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. Microbes quite likely exist in abundance but complex life not. This argument was first set forth in the book Rare Earth: Why Complex Life is Uncommon in the Universe by Peter Ward, Donald Brownlee. [/ QUOTE ] even if its uncommon tho, the incredibly vast number of other stars/planets in the universe means its pretty likely its happened elsewhere. [/ QUOTE ] This doesn't make sense. If it's uncommon it's not likely to have happened. Moreover the probability of a planet supporting life can be so small that even given the vast number of planets in the universe the expected number of planets supporting life can still be small. Say for example there the probability that planet supports life is 10^-15 and there are 10^9 planets in the universe. It doesn't matter how close these numbers are to the actual numbers the point is this: the expected number of planets supporting life is 10^-15 * 10^9 = 10^-6 = 1/1000000.
|
|
#7
12-13-2005, 10:22 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
[ QUOTE ] [ QUOTE ] [ QUOTE ] id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely. [/ QUOTE ] Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. Microbes quite likely exist in abundance but complex life not. This argument was first set forth in the book Rare Earth: Why Complex Life is Uncommon in the Universe by Peter Ward, Donald Brownlee. [/ QUOTE ] even if its uncommon tho, the incredibly vast number of other stars/planets in the universe means its pretty likely its happened elsewhere. [/ QUOTE ] This doesn't make sense. If it's uncommon it's not likely to have happened. Moreover the probability of a planet supporting life can be so small that even given the vast number of planets in the universe the expected number of planets supporting life can still be small. Say for example there the probability that planet supports life is 10^-15 and there are 10^9 planets in the universe. It doesn't matter how close these numbers are to the actual numbers the point is this: the expected number of planets supporting life is 10^-15 * 10^9 = 10^-6 = 1/1000000. [/ QUOTE ] I met an alien once, his name was Pablo. Therefore you must be wrong. TT [img]/images/graemlins/club.gif[/img]
|
|
#8
12-13-2005, 11:08 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
Moreover the probability of a planet supporting life can be so small that even given the vast number of planets in the universe the expected number of planets supporting life can still be small. Say for example there the probability that planet supports life is 10^-15 and there are 10^9 planets in the universe. It doesn't matter how close these numbers are to the actual numbers the point is this: the expected number of planets supporting life is 10^-15 * 10^9 = 10^-6 = 1/1000000. [/ QUOTE ] actually I don't think this is right. it's 1 - [probability of life not existing on all 10^9 planets] which is 1 - (99999999999999/100000000000000)^9 and my calculator can't seem to handle that business. I think it's smaller than your estimate though.
|
|
#9
12-13-2005, 05:53 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. [/ QUOTE ] while this may be true, the universe is extremely large and we really dont know that much about it relativley speaking.
|
|
#10
12-13-2005, 06:02 PM
|
|||
|
|||
|
Re: Have aliens visited earth?
[ QUOTE ]
[ QUOTE ] id say its probable for other intelligent life to exist somewhere. getting here is highly unlikely. [/ QUOTE ] Actually, the conditions for life to exist are extremely rare. Life as we know it is extremely fragile and it appears, based on probabilistic arguments, that the conditions for life to exist are not that common in the universe. Microbes quite likely exist in abundance but complex life not. This argument was first set forth in the book Rare Earth: Why Complex Life is Uncommon in the Universe by Peter Ward, Donald Brownlee. [/ QUOTE ] As the previous poster said, the number are just too big not for it to have happened elsewhere. 100 billion (10^11) stars in the Milky Way alone, probably 100 biliion galaxys. There are four worlds where life may originiate in our system alone (Earth, Mars, Europa, Titan). Say 25% of all systems have planets, so you've got 100 billion planets in the Milky Way where it has been/will be possible, 10^22 in the universe. One could be vast orders of magitude off on probablity estimates and still have almost uncountable intelligent civilizations in the universe, let alone planets where there is mere life.
|
|
|
|
Hybrid Mode
