My @Quora answer to What are some theories on why we haven’t been visited by aliens yet?
Answer by Thaddeus Howze:
The Fermi paradox: It’s complicated.
- Fortunately I have found a video that breaks down the Fermi Paradox into its component concepts in simple, four-color splendor. If you like it support the creators. It took them 200 hours to create it.
- When you are done with this video, you will understand the basic premise for why we suspect the Universe is quiet. Some of these ideas are positively terrifying to conceive of.
- The empty dead universe concept is even more terrifying to conceive of. An entire universe with no life in it but us. And we are poised on the edge of nuclear war, climate change, asteroid strike, plague, and run away capitalism. The universe may be more screwed than it knows if its depending on US to fill it with new life.
Associated with the Fermi Paradox is The Drake Equation
“What do we need to know about to discover life in space?”
How can we estimate the number of technological civilizations that might exist among the stars? — Frank Drake, 1961
- While working as a radio astronomer at the National Radio Astronomy Observatory in Green Bank, West Virginia, Dr. Frank Drake conceived an approach to bound the terms involved in estimating the number of technological civilizations that may exist in our galaxy.
- The Drake Equation, as it has become known, was first presented by Drake in 1961 and identifies specific factors thought to play a role in the development of such civilizations.
- Although there is no unique solution to this equation, it is a generally accepted tool used by the scientific community to examine these factors.
REFERENCES:
Wikipedia: Fermi paradox
SETI Institute: The Drake Equation
Kurzgesagt Information DesignVIDEOS:
Kurz Gesagt – In a Nutshell: The Fermi Paradox video
Drake Equation Video: Published on Aug 9, 2013 – Animation explaining famous Drake Equation with the voice of COSMOS editor Wilson da Silva.
What are some theories on why we haven’t been visited by aliens yet?
A Matter of Scale 
Awesome video… end positive unless of course we venture forth and that is the trigger for the super duper galactic bug exterminator to turn up… I still vote we go for it!
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