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Grabby aliens model

A team of scientists say that ‘grabby aliens’ are needed to explain why we humans have appeared so soon after the big bang, and that our descendants would encounter them in roughly a billion years’ time.

To calculate such numbers, four researchers, led by Professor Robin Hanson from George Mason University, USA, and including our PHD student Daniel Martin, have built a simple model to show alien civilisations. 

Understanding a ‘grabby alien’

The research team developed the model based on the parameters which are set by relevant cosmological data. In particular, the current age of the universe, the fact we humans have yet to see aliens in our sky, and the timing of key events in Earth’s history. 

The model shows many cones within a particular area of the universe. Each cone represents one civilisation, some of which will survive for a long period of time or choose to expand rapidly until it meets another civilisation.

Lead researcher Prof. Robin Hanson called the rapidly expanding civilisations ‘Grabby Aliens’ because they last a long time, expand fast, and change the spaces they enter to meet their needs.

Early existence of humanity

The team believes the existence of ‘grabby aliens’ provides an answer to the puzzle of why humans have appeared so soon after the big bang. 

If ‘grabby aliens’ will at some point, occupy all of the universe, it could be seen that human civilisation has been set a deadline to appear, if it’s not to arrive within a ‘grabby alien’ controlled environment. 

The team estimate that such aliens appear once per million galaxies, and they now occupy about half of the space in the universe. Furthermore they continue to state that our descendants, should we avoid extinction, can expect an alien encounter in roughly a billion years’ time. 

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