What is this huge symbol on the door in the Truth realm and in the Neon Genesis Evangelion opening? In Fullmetal Alchemist the door in the Truth realm has a huge symbol with all kinds of things on it:



I've seen the opening of Neon Genesis Evangelion today and noticed that the same symbol is shown in the beginning of the opening around 0:10 - 0:13.

I first thought that it was just a random symbol in FMA, but now that I've seen it in the opening of NGE, I believe that it must come from something else since there is no connection between those anime. 

What is this symbol, where does it come from and what does it describe?

Here is a more detailed picture of the symbol:
It's a slightly modified version of the Sephirothic Tree of Life as defined by Robert Fludd, who was a physician with interests in Kabbalah and other religious mysticisms. The globes (called Sephiroths) are thought of as being ways in which the universe shows its truths to humanity. They're also printed with the words God used in creating the universe in Genesis.



You can read up on it more here, but the basic idea behind it is that it is a mystic symbol representing universal truth -- and the Truth is on the other side of the door in FMA.

In NGE, however, the symbol appears after the Mass Production units form an inverted tree of life, symbolizing the opposite of creation -- destruction, death -- after crucifying Eva 01. This is part of the Third Impact, in which nearly all of humanity is reduced to LCL. You'll find that there's a lot of mystic symbolism in NGE.