deletions | additions       diff --git a/Now_we_have_some_constraints__.tex b/Now_we_have_some_constraints__.tex  index 67ef4fe..34958c1 100644  --- a/Now_we_have_some_constraints__.tex  +++ b/Now_we_have_some_constraints__.tex 
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Ok I know I know, there is \href{http://en.wikipedia.org/wiki/Roswell_UFO_incident}{Roswell}... the \href{http://en.wikipedia.org/wiki/Wow!_signal}{WOW signal}... \href{http://en.wikipedia.org/wiki/List_of_reported_UFO_sightings}{UFO} sightings... Well, I am not going into that. I will just state that the most economical explanations for all the aforementioned cases have nothing to do with E.T. and that at this time there is no clear evidence that prove we had contact with alien life. People let's use the \href{http://bit.ly/KDLFp6}{Occam's razor} and throw away the conspiracy spoon.  Back to us. The Fermi Paradox implies that $N$ is probably a small number\footnote{There are alternative solutions to the Fermi Paradox, Paradox and  some can do not require $N$ to  be found in small, for a nice review have  a look at this  \href{http://waitbutwhy.com/2014/05/fermi-paradox.html}{great post} from Tim Urban's}. Our revised version of the Drake Equation then leaves two interesting alternatives: \begin{enumerate} \item $f_i$ is a small number. That is\textbf{ life is common in the Universe, but intelligent life is not}.  \item $L$ is a small number. Intelligent \textbf{life do not spend much time in the communicative phase}.  \end{enumerate}