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But the Gemini pattern keeps itself going by continuously reconstructing itself, in *spite* of the way the universe normally works.

how so?

I was hoping someone would ask that. Let me start out with a comparison to other cellular automata. Conway's Life is B3/S23 -- "born if 3 neighbors, survives if 2 or 3 neighbors". There are other rules, such as HighLife (B36/S23, very close to Conway's Life) in which a 12-cell pattern can replicate itself -- after 12 generations there are 2 copies, after 36 ticks there are 4 copies, and so on. This pattern regularly evolves from random starting states.

There's even a rule, Fredkin's parity rule (B1357/S1257) where every possible pattern is a replicator -- an extreme example of replication being "just the way the universe works". But these replicators are, in some sense, too simple to be very interesting! They replicate the way crystals grow, and it's hard to harness that kind of low-level behavior. If you wanted a HighLife replicator with 13 cells, or one that would replicate in 13 ticks, instead of 12, you'd be out of luck. By comparison, the Gemini spaceship is extraordinarily adjustable.

will this pattern repair itself if anything happens to it? will it protect itself from outside influences? like a cell wall protects the inside of a cell?

No to all of the above. Conway's Life is not amenable to error-correction of this kind, because small changes have such huge consequences. Kind of like building machinery out of chunks of sub-critical enriched uranium: you can design it so that during normal operation the various pieces never come close enough together to start a chain reaction, but if any little thing goes wrong, you end up with high-energy particles flying all over the place, spreading the reaction to other nearby machinery, which then contributes to the explosion.

so how is it reconstructing itself in spite of the things around it?

Well, I didn't say "in spite of the things around it" -- it was "in spite of the way the universe normally works." The Life universe, for random patterns anyway, normally settles into a scattering of stable or P2-oscillating ash after a few hundred or a few thousand generations. There are any number of "lucky" self-perpetuating stationary and moving patterns that are exceptions to this general rule, but they're all very delicately balanced on the edge of chaos.

how is this anything but a different kind of glider?

The Gemini spaceship contains a large amount of data in its glider channels that is recognizably information about its own structure. Change that data, and the replicator unit will (usually) build something different. Most other gliders and spaceships in Conway's Life don't have anything like this -- all the other hundreds of patterns in Golly's Spaceships folder, or the tens of thousands in Koenig's Life Object database, are "naturally" self-perpetuating, because a future generation of the pattern happens to be identical to the original.

The Gemini spaceship has a significantly higher degree of control over its environment: with the right change to its program, a Gemini replicator unit could construct anything that can be built by colliding gliders, in any empty space in the Life universe. The Gemini contains most or all of the construction tools that a Conway's Life self-replicator will need; it's just a few short steps away from being a true replicator. Mostly it just doesn't have the right program -- yet.

There are a few other large patterns, especially Gabriel Nivasch's Caterpillar, that blur this line to some extent. However, the pi-climber "data" in the Caterpillar is much more difficult to reprogram than the gliders in the Gemini. Several new variants of the Gemini with different speeds and angles of travel have already been built -- with a lot of help from the Python scripts that Andrew Wade made available along with the pattern..

Reporters in Palestinian areas have been threatened that their lives may be in danger if they publicize pictures of palestinians celebrating the WTC and Pentagon disasters. This is similar to threats which Italian reporters received when they documented the lyniching of Israelis in ramalla by a palestinian mob a few months ago.

Here's a report about it from AP (you can find more on this at The Jerusalem Post.

You can see a picture of this at my page

Arafat horrified; Palestinians celebrating
By Mohammed Daraghmeh, The Associated Press

NABLUS, West Bank (AP) - Thousands of Palestinians celebrated toiday's terror attacks in the United States, chanting "God is Great" and distributing candy to passers-by, even as their leader, Yasser Arafat, said he was horrified.

The US government has become increasingly unpopular in the West Bank and Gaza Strip in the past year of Israeli-Palestinian fighting, with many Palestinians accusing Washington of siding with Israel.

In the West Bank town of Nablus, about 3,000 people poured into the street shortly after the attacks on the World Trade Center in New York and government targets in Washington.

Demonstrators distributed candy in a traditional gesture of celebration. Several Palestinian gunmen shot in the air, while other marchers carried Palestinian flags.

Nawal Abdel Fatah, 48, wearing a long black dress, threw sweets in the air, saying she was happy because "America is the head of the snake, America always stands by Israel in its war against us."

Her daughter Maysoon, 22, said she hoped the next attack would be launched against Tel Aviv.

In traditionally Arab eastern Jerusalem, there was a smaller gathering of about two dozen people, many of them young children led in chants by adults. Some drivers passing the scene honked their horns and flashed victory signs from their windows.

This script will encrypt a song title in a person-readable yet machine-meaningless form. You could use something like this in a "pirate" napster client. Better yet, someone should write a napster client which renames all of your files with a real encryption, and then the client is needed to decrypt them.

Download DeCSS.

This link goes to a CGI which redirects to a random link pulled from 2600's plain text list of links. This means that my site does not contain any DeCSS code, nor does it contain links to DeCSS code. If 2600's page is now legit, then my script links to a legal page. Yet, if you click on the above link, you get code. Hmmm...

Source code here (warning - I wrote it in about 3 minutes).

Download DeCSS.

This link goes to a CGI which redirects to a random link pulled from 2600's plain text list of links. This means that my site does not contain any DeCSS code, nor does it contain links to DeCSS code. If 2600's page is now legit, then my script links to a legal page. Yet, if you click on the above link, you get code. Hmmm...

Source code here (warning - I wrote it in about 3 minutes).

I agree that fun 404s have become a nice amusement on the web. At least they avoid the two biggest problems with standard ones: telling people to contact the sysadmin, especially on a many-user machine, and telling people they must've typed something wrong, when people almost never type URLs.

A method of tracking a web browser across distinct domains of a network of computers includes the step of identifying, at a first server computer with a first domain name, a first request from the web browser. The web browser is then assigned a unique identification code. The unique identification code is then conveyed to a second server with a second domain name that is distinct from the first domain name. A request by the web browser to the second server computer is associated with the web browser via the unique identification code. In this way, the web browser is tracked across distinct domains of the World Wide Web. As a result, the web browser can be passively tracked to identify content preferences and interests associated with the individual using the web browser.