the earth is a relatively young part of the planetary system, therefore, there might be more advanced than we aliens exist in the universe.This is a problem: all of the aliens in where?
just recently, professor of physics and astronomy at the university of Manchester, England tried to answer this is generally known as the problem of the Fermi paradox.
a study in the proceedings of the national academy of sciences argues that the universe all stars have earth-like planets around them, at least 1% means that there may be 1 trillion earth-like planets.
for those who doubt the aliens, let's make a conservative estimate, if after the existence of the 1 billion, only 1% developed these planets in the life.But even if only 1% developed and equal human wisdom, which means that the universe has one quadrillion intellectual civilization.
if you use the same estimated to reduce these Numbers, to predict how much wisdom civilization exists the Milky Way, so just in our galaxy, there will be 1 billion earth-like planets and 100000 intellectual civilization.
the astronomers are given the following reasons:
1, the theoretical physicist Brian Cox
the Fermi paradox of a solution is that one has the ability to destroy your world can't operation, but also need global cooperation to prevent it from happening.May be the growth of science and engineering, inevitably, more than the development of political expertise, lead to disaster.We may be close to the situation.
2, big filter theory
created by an associate professor at George mason university.Big filter theory holds that evolution is a very difficult life step, this step is prevention of civilization to achieve interstellar travel.The question is: compared with big filter, we are now and how far is it big at the end of the filter?
3, aliens are constantly visit our
we currently living in the 3 d world.As a collective, we are not in and out of the higher dimensions.If a higher wisdom of civilization in the fourth dimension, we can't see them as a 3 d creatures, let alone to communicate with them.
these theories which one do you believe that?