the Hodge Podge machine

[Elmer Fudd]

howdi net,
a few CA questions:

1 - does anyone have an implementation of a hodge-podge machine
(any machine, any language) that they wouldn't mind sharing
2 - in the game of life, are there any 2 "creatures" that combine
to produce anihilation of one and unadulterated survival of
the other?

thanks
-gil

[Allan C. Wechsler]

Date: Mon, 4 May 1992 16:40 EDT
From: g...@cse.ucsc.edu (Elmer Fudd)

howdi net,
a few CA questions:

1 - does anyone have an implementation of a hodge-podge machine
(any machine, any language) that they wouldn't mind sharing

I have one in Lisp for the Symbolics. I don't vouch for its quality.

2 - in the game of life, are there any 2 "creatures" that combine
to produce anihilation of one and unadulterated survival of
the other?

You have to say what you mean by "combine", and you obviously have some
unspoken conditions. Consider the case where creature A is a single bit
and creature B is a (standard, 2x2) block. Put them far enough apart
and the bit dies but the block lives. This is clearly not what you
meant. What _did_ you mean?

[Danny Boulet]

I've seen a glider gun and target in which the gliders are emitted by
the gun and consumed by the target. The target is unaffected by the
glider. The target and a glider would seem to satisfy your request.
I don't have an exact description of the objects but I'm fairly sure
that it is a 'standard' configuration provided as a common example.
-Danny
>
>thanks
>-gil

[Holocaust-->Travesty]

>>2 - in the game of life, are there any 2 "creatures" that combine
>> to produce anihilation of one and unadulterated survival of
>> the other?
>I've seen a glider gun and target in which the gliders are emitted by
>the gun and consumed by the target. The target is unaffected by the
>glider. The target and a glider would seem to satisfy your request.
>I don't have an exact description of the objects but I'm fairly sure
>that it is a 'standard' configuration provided as a common example.
>-Danny

>>-gil

I think you're talking about a configuration known as "eater,"
a still life in 6-8 cells. If the glider hits the right spot,
the eater will form a bridge and destroy the glider while
undergoing little change before reverting.
I think it looks like this:

Contact\
**
*
***
*

But that's just a guess.

[Mark A Biggar]

In article <1992050422...@PALLANDO.SCRC.Symbolics.COM> A...@RIVERSIDE.SCRC.Symbolics.COM (Allan C. Wechsler) writes:
> 2 - in the game of life, are there any 2 "creatures" that combine
> to produce anihilation of one and unadulterated survival of
> the other?
>You have to say what you mean by "combine", and you obviously have some
>unspoken conditions. Consider the case where creature A is a single bit
>and creature B is a (standard, 2x2) block. Put them far enough apart
>and the bit dies but the block lives. This is clearly not what you
>meant. What _did_ you mean?

There are colisions between gliders and blocks that leave just the block,
but offset a little. A sutiblly constructed flotilla of gliders can be
used to move blocks around on the field. For more info see Volume 2:
"Winning Ways for Your Mathetical Plays", Berlekamp, Conway & Guy.

There is also a configuration called an "eater" which will eat a stream
of glider and remain unchanged.

--
Mark Biggar
m...@wdl1.wdl.loral.com