Wouter Verhelst: It's life, Jim, but not as we know it.
...or so Spock said. Apparrently.
Yesterday, for some reason, I was reading something on Wikipedia. Don't ask me what I
started with, I don't remember; however, my journey through Wikipedia
eventually got me to the Rare Earth
hypothesis, the Principle of
Mediocrity, and other related things.
Both are subjects relating to whether or not there would be life on
other planets. The latter claims that this is, in fact, quite likely;
the Principle of Mediocrity basically says that "Earth is a relatively
ordinary planet orbiting a relatively ordinary star in a relatively
ordinary galaxy which is one of countless others in a giant universe,
possibly within an infinite multiverse". This is supported by a number
of astronomical findings.
The contrast to that, the Rare Earth hypothesis, claims that Earth
is, in fact, not a very ordinary planet. That to be able to
reach a point where complex multicellular can have evolved—such as
on Earth—such a high number of variables have to have the
exact right value, with in many cases such low margins
for errors, that while possible, the likelihood that life would exist on
other planets is very low.
They were both interesting reads. However, there is one thing to
which I did not find an answer: Why does it have to be
Earth-like life?
As I understand the theory of our origins, life began on the Planet
Earth in a relatively stable body of unclean water—known as the
"Oersoep" in Dutch, though I couldn't find the English term for
that—on which the sun shone; that sunshine made the elements of
the "oersoep" react with eachother so that it eventually formed
single-cell life, which then evolved into multi-cellular life, and so
on. Even today, the sun still shines on Earth, and almost all energy in
use on Earth can in some way or another be attributed to something that
once received sunlight; I suspect the only exception to that is nuclear
energy.
As I understand the Rare Earth hypothesis and the Principle of
Mediocrity, both seem to assume the basic premise that the only way in
which life could evolve is the way in which it evolved on Earth; that
is, you need direct sunlight so that you can have some chemical
reactions. You cannot have too much ultraviolet, gamma, or x-ray
radiation, because that would kill life. You cannot have too many
impacts of extraplanetarian bodies, such as comets or asteroids, because
these impacts and the resulting fallout would destroy life.
I did not find any argument for that assertion, however; and what I
don't see is why it would be necessary. We could define the "oersoep" as
some sort of a "stable chaos": a bunch of chemical elements and a
varying external influence (sunlight) means that you have a brewing and
reacting bunch of matter, where the composition of the matter is
constantly changing; however, at the same time, when viewed over a large
amount of time, not much did in fact change. The varying external
influences have a regular and stable rhythm; the sun appears in the
morning and disappears in the evening. The sun shines longer in summer
than it does in winter. While it is not the same all the time, there is
predictability. If a number of chemical elements react with eachother in
a certain way on one day, then they will react the same way again the
next day. If this happens for years on end, you may have a series of
reactions that is more or less reproducible, where the final result of
all the chemical reactions turns out to be the original starting point
again. At least almost so. Such a series of chemical reactions could be
called "life", especially if it occurs within a small group of chemicals
that sticks together, like a cell.
While a body of unclean water with regular sunshine certainly is one
way to get to a series of repetitive chemical reactions, I fail to see
why it would have to be the only possible way. If there were a planet
composed mainly of Helium (rather than Hydrogen and Carbon, as on Earth)
but also containing a bunch of other elements (so that they can react
with eachother) with a star that sends out lots of gamma radiation and
an atmosphere which blocks sunlight (I don't know whether Helium can do
that, but let's assume it can), then I do not see why it would not be
possible for life to evolve on such a planet which would be based on
Helium rather than Carbon and Water, and which would require gamma
radiation to survive but would die when brought into prolonged contact
with light, just like we will die when brought into prolonged contact
with gamma radiation.
Another example could be a planet where every year a comet of
approximately the same composition impacts on the same place on the
planet's surface. Such an impact would regularly stir up the chemical
elements on this planet, and could provide the needed energy to produce
the chemical reactions required to sustain life. If any life were to
evolve on this planet, not only would it be able to survive such
constant extraplanetary impacts, it would also require these
impacts to continue in order to survive.
I haven't been able to find any information on that. It would seem
that either I'm missing something very basic, or that nobody has thought
of this before—and I would find that highly unlikely. So, anyone
who's been thinking longer than me about this subject (that is to say,
just a few hours) who could enlighten me?
Of course, one answer could be to say that God created all life, and
that the evolution theory is only a theory, which is not grounded in any
reality. But make a comment to that effect on my blog, and I will
moderate it away. After having a good-hearted laugh at it.
They represent exactly the same thing, yet someone who knows music
needs a split second to decode the below but a few seconds for the above
(if they understand lilypond's syntaxis). In fact, at first I thought
that I had done something wrong in invoking lilypond-book to
produce that snippet, because I had misparsed the code above (which,
incidentally, is one bar of some actual music that I have in my
~/data/audio/lilypond directory)
The plain text interface certainly does have some
advantages, but IMO the downsides by far outweigh the benefits. In
general, lilypond is not well suited as a way to actually write
music, as opposed to simply typesetting already existing music. I did
actually follow a course on harmonics (although I never finished it due
to lack of time); when writing some new piece, I find that it often far
easier to do the actual writing on a piece of paper and then enter that
in lilypond syntaxis, rather than getting distracted over the lilypond
syntaxis while trying to concentrate on what chords I can and/or want to
use. It is unnatural, and would look like a Japanese person being forced
to read and write texts like 'gaka ga e o kaita' which then get
postprocesssed into something like ' ' (look ma,
Unicode!). Or, in other words: why isn't there just an input method to
write music? There are unicode characters for musical notes,
you know...
When comparing lilypond to finale, it is not hard to understand that
entering music in a graphical environment is just so much easier. When I
last used it, Finale had four input methods: one with keyboard and mouse
(use the numeric keys on the keyboard to enter the desired note length
and the mouse to enter the pitch); one with keyboard only (use abcdefg
etc. to choose the pitch, and the same numeric keys to enter the desired
length); one with keyboard and MIDI keyboard (use the numeric keys to
enter a desired note length, and just press a note on the MIDI keyboard
to choose it); and finally, it can also quantisise music as you play it
(which is the fastest, but least accurate, method to enter music).
Lilypond only allows entering music with the keyboard directly, and then
only displays notes after 'compiling' them, so that you cannot see your
mistakes and typos until much later. I'm disregarding midi2ly, which
converts MIDI files to lilypond input files in a reasonably good way;
but Finale has MIDI import functionality as well, I do not consider that
to be an 'Input Method' as such.
After having entered the music, a musician will want to do something
with it. Have the computer play it, for instance, or print it out so
that he or she can rehearse it and eventually play it themselves.
Lilypond will do neither by itself; however, it can produce postscript,
PDF, and DVI files which one can use to print, and/or MIDI files which
one can have the computer play. The printouts are great, as I've said
before; but playing the MIDI files is another matter entirely.
As I've explained earlier, playing MIDI used to be done through
hardware. When I still had a working SB16-compatible card, I could play
MIDI files on my computer perfectly fine by just using the driver for
that sound card. Since I currently depend mostly on ESS1371-compatible
cards, that do not havve any hardware MIDI synthesizer, however, that
doesn't work. So I have to use software sequencing instead. On Windows,
software sequencing is done by the sound card's driver. On Linux, there
is no software sequencing being done by any driver, so it all has to be
done in userland. In theory, that's just fine. Unfortunately, the
implementation sucks.
The only software MIDI synthesizer available on Debian is