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Are We Alone In the Universe? Not Likely, According To Math (cnet.com)
An anonymous reader writes: An equation, which calculates the probability of the evolution of other technological civilizations, has found that it's wildly unlikely we're the only time advanced society in the universe. Adam Frank from the University of Rochester and Woodruff Sullivan from the University of Washington base their new equation on the Drake equation, used for calculating the probability of extraterrestrial civilisation, written by astronomer and astrophysicist Frank Drake in 1961. The scientists also take into account Kepler, which suggests that one in five stars have planets in the habitable zone. Frank and Sullivan calculated that human civilisation is only unique if the odds of a civilisation developing on a habitable planet are less than one in 10 billion trillion. "One in 10 billion trillion is incredibly small. To me, this implies that other intelligent, technology producing species very likely have evolved before us," Frank said. Frank said: "Of course, we have no idea how likely it is that an intelligent technological species will evolve on a given habitable planet. But using our method we can tell exactly how low that probability would have to be for us to be the ONLY civilization the Universe has produced. We call that the pessimism line. If the actual probability is greater than the pessimism line, then a technological species and civilization has likely happened before."
it's almost as if someone intelligent designed us....
incoming shitstorm
Seriously, we're not that complex. A few billion years is an incredible amount of time.
Seven puppies were harmed during the making of this post.
“It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.”
as the relationship between the information processing rate (bit/s) of each individual processing unit (neuron), the weight/size of a single unit and the total number of processing units (expressed as mass).
At present, human scientists are attempting to communicate outside our species to primates and cetaceans, and in a limited way to a few other vertebrates. This is inordinately difficult, and yet it represents a gap of at most a few SQ points. The farthest we can reach in our "communication" with vegetation is when we plant, water, or fertilize it, but it is evident that messages transmitted across an SQ gap of 10 points or more cannot be very meaningful. What, then, could an SQ +50 Superbeing possibly have to say to us?
Who are WE to determine that life has to be like US.
Well, obviously that's silly, however...
Why assume life out there would be carbon based, breath, and require water?
Because we don't know any better. It's likely that carbon is important. There are several reasons for this. First, it forms stable, complex molecules over a wide range of temperatures. Silicon does to some extent, though the upper limit on the temperature is much lower. Boron also formes long complex molecules readily. There might be options with some metals too.
However abundance is also key. Boron is not formed in stellar nucleosynthesis un significant quantities unlike silicon and carbon, so it is very rare. This is a downside for life, since some non living process would have to concentrate it first.
The next problem is solvents. Likely solvents are hydrocarbons, ammonia, water, sulphuric acid and possibly liquid or supercritical gasses like nitrogen or hydrogen. We know those do exist out there in space. More exotic solvents may well depend on a large quantities of large molecules being formed (unlikely) or concentration of rare elements (also unlikely).
Those solvents will affect what chemistries are possible and what the base molecules are.
Now, the thing with carbon is that it comes in a variety of forms ready made. There's plenty of methane around the solar system, and the interaction with UV makes various other molecules too. However, silicon just doesn't seem to do that which puts it at a disadvantage. Likewise, CO2 is a nice gas which can spread itself around, unlike SiO2 which is rather more rooted to the ground.
So, while there might be non carbon forms of life, the other elements are at a severe disadvantage.
As for solvents, yeah I can see other ones could work. There's a few choices.
SJW n. One who posts facts.
Therefore, there must be a finite number of inhabited worlds. False, as you point out - supposing that the premises are true, the number of inhabited worlds may or may not be infinite.
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