Thursday, August 26, 2010

Where is Everybody?

"New Ideas" - That's what make our life interesting. Here is one... I copied exactly from the source

A new model shows how the spread of ET civilisations can undergo phase changes, providing a deeper insights into the Fermi Paradox.

In 1950, the Italian physicist Enrico Fermi raised the question that now bears his name. If there are intelligent civilisations elsewhere in the Universe with technologies that far surpass our own, why do we see no sign of them?

Since then, the so-called Fermi Paradox has puzzled astronomers and science fiction writers alike. And although there are no shortage of ways to approach the problem (this blog has covered them here and here for example), nobody has come up with a convincing explanation. .

Now there is another take on the problem thanks to a new approach by Igor Bezsudnov and Andrey Snarskii at the National Technical University of Ukraine.

Their approach is to imagine that civilisations form at a certain rate, grow to fill a certain volume of space and then collapse and die. They even go as far as to suggest that civilisations have a characteristic life time, which limits how big they can become.

In certain circumstances, however, when civilisations are close enough together in time and space, they can come into contact and when this happens the cross-fertilisation of ideas and cultures allows them both to flourish in a way that increases their combined lifespan.

Bezsudnov and Snarskii point out that this process of spreading into space can be easily modelled using a cellular automaton. And they've gone ahead and created their own universe using a 10,000 x 10,000 cell automaton running over 320,000 steps.

The parameters that govern the evolution of this universe are simple: the probability of a civilisation forming, the usual lifespan of such a civilisation and the extra bonus time civilisations get when they meet.

The result gives a new insight into the Fermi Paradox. Bezsudnov and Snarskii say that for certain values of these parameters, the universe undergoes a phase change from one in which civilisations tend not to meet and spread into one in which the entire universe tends to become civilised as different groups meet and spread.

Bezsudnov and Snarskii even derive an inequality that a universe must satisfy to become civilised. This, they say, is analogous to the famous Drake equation which attempts to quantify the number of other contactable civilisations in the universe right now.

The question of course is what kind of universe do we live in: are the parameters here ripe for the evolution of a single cosmic civilisation or are we condemned to be forever alone?

Bezsudnov and Snarskii say there's only one way to find out: wait and see.

Thanks to the source

Ref:arxiv.org/abs/1007.2774

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