Those are the people who have artificial lifeforms in their computers. I agree only "eat", expel waste, and multiply are required for living.
Is there life out there? Yes. 100% definitley. Is there intelligent life? Very, very likely. Is there life out there trying to communicate? Extremely likely. Is there life out there older and more advanced than we are? Probably.
In 1961 Frank Drake formulated an equation designed to factor all the variables regarding the communicative extra terrestrial lifeforms. The Drake equation is as follows: N = N* fp ne fl fi fc fL
N* represents the number of stars in the Milky Way Galaxy
estimates are 100 billion.
fp is the fraction of stars that have planets around them
estimates range from 20% to 50%. (so we will go with 35%)
ne is the number of planets per star that are capable of sustaining life
estimates range from 1 to 5. (I dont think every star has one, so I will say .3, or one out of three)
fl is the fraction of planets in ne where life evolves
estimates range from 100% (where life can evolve it will) down to close to 0%. (We will use 75%)
fi is the fraction of fl where intelligent life evolves
stimates range from 100% down to near 0%. (We'll go with 50% to be fair)
fc is the fraction of fi that communicate
10% to 20% (Again, we will take the average and go with 15%)
fL is fraction of the planet's life during which the communicating civilizations live
If we use earth as an example, and we survive for 1,000,000 years the answer will be 1/10,000th.
So now the equation,
N = Number of communicating civilizations
N=100,000,000,000*35%*.33*75%*50%*15%*0.0001
N=35,000,000,000*.33*75%*50%*15%*0.0001
N=11,550,000,000*75%*50%*15%*0.0001
N=8,662,500,000*50%*15%*0.0001
N=4,331,250,000*15%*0.0001
N=649,687,500*0.0001
N=64968.75
Remember I chose to be more conservative than than others in my equation, but if you want to be even more conservative, and say that the civilization will only last for 100,000 years, then N=6496.88.
