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The idea of trees communicating, and all the threes on the planet forming a kind of collective 'brain' is interesting. But for organism like a tree, who are stationary, and not being able to move there is not much purpose in developing senses and a neural network. And all the animals having antennae is also weird. Why would the animals develop such an organ. In the later part of the film there also seems to be a lot telepathic communication going on between the 'trees' and the animals.

*Hersenschimmen*by J. Bernlef. Including DVD with the movie*Hersenschimmen*. ISBN:9789021453194. € 9.99.*Buiten is het maandag*by J. Bernlef. ISBN:9789021452784. € 5.99.*Maak mij blij*by Karin Giphart. Including DVD. ISBN:9789038827285. € 4.99.

Dusseldorf - Amsterdam 12/07 CZ 7786 18:25 19:20 Amsterdam - Beijing 12/07 CZ 346 20:55 12:40 Beijing - Urumqi 13/07 CZ 6908 15:45 19:45 Urumqi - Beijing 29/07 CZ 6911 08:10 11:45 Beijing - Amsterdam 29/07 CZ 345 14:20 18:35 Amsterdam - Dusseldorf 29/07 CZ 7781 21:40 22:30

The reason we are flying from Düsseldorf (Germany) is because this is about 200 euro (per person) cheaper than flying from Amsterdam. We will drive by car to Düsseldorf, which is less than two hours from where we live and park our car there (which will cost about 100 euro). Traveling by train from Enschede to Amsterdam would also cost more than 100 euro.

Not so long a go, it was proven (see *The Complexity of Flood Filling Games*) that the
Flood-It! game is
NP-hard, which means that it is at least NP-complete, but possibly
even more complex. Robert
Aubrey Hearn deals with the complexity of many games in his PhD
thesis *Games, Puzzles and Computation*.

The NP-complete problem that I have worked on the most is the Exact Cover problem. This made me think about answering the question whether there is an 'easy' algorithm for solving Exact Cover problems. I am very strongly inclined to believe that such an algorith does not exist and that the complexity classes NP and P are not equal. Many computer scientist and complexity expert share this opinion. The problem is that it is very difficult to proof, because you have to show that something does not exists, while there are an almost unlimited number of 'easy' algorithms. Many people already have tried to proof the equality or unequality of NP and P. For more information see The P-versus-NP page by Gerhard J. Woeginger. The paper Faster Solutions for Exact Hitting Set and Exact SAT by Limor Drori and David Peleg, seem to contain some interesting algoritms that shows that Exact Cover problems can be solved in a rather low exponent.

There are some more techniques which point to efficient algorithms for solving NP-complete problems. These are found in:

- Holographic Algorithms by Jin-Yi Cai
- Efficiency of structured adiabatic quantum computation
- Quantum Computation by Adiabatic Evolution

Today, yesterday's earthquake was reclassified as two earthquakes: one 1.0 earthquake at a depth of 7.1 km at 63.695, -19.149 and one 1.5 earthquake at a depth of 0.8 km at 63.668, -19.141. This very interesting because the later earthquake occured above the magna chamber.

**Update April 30:** Above the 'Katla' tremor page it now says: "Katla is **not** erupting
and there are **no** indications that Katla is about to erupt.
Information on this page is for the Eyjafjallajökull eruption."

- 8: Holographic Algorithms by Jin-Yi Cai
- 9: Efficiency of structured adiabatic quantum computation
- 9: Quantum Computation by Adiabatic Evolution
- 20: James Robert Mylne
- 20: The Complexity of Flood Filling Games
- 20: Games, Puzzles and Computation
- 23: Cryptococcus gattii VGIIc

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