Re: Communication between cells...

[Howard Pattee <***>]

At 04:47 PM 1/20/05 -0500, Judith asks:
> I don't know why you refer to
> temporal aspects as "one dimensional", though. Could you
> elaborate on that?

Time can be represented (modeled) by numbers on a one-dimensional line.
One particular time can be represented by one number. That means it is a
one-dimensional or a scalar quantity. Rosen's Chronicles are such a time
line or time series. As you know, your position in space requires 3
numbers, so it is three-dimensional. If I want to meet you for lunch, I
have to specify 4 dimensions, 3 for where and one for when.

> Judith: In any case, there are
> aspects of this which fascinate me. Like; just because the
> "information capacity" of electrical signals is small, why
> would that be any reflection on how important this aspect is in the
> overall organization?

HP: We have good measures of syntactic information capacity (e.g.
Shannon's logN bits). There is no good way to measure the importance of
semantic information. Importance is mostly a subjective value judgement.
In the cell one bad bit can be lethal, irrelevant, or anywhere in
between. 

>  Judith: What if there's
> far more information being transmitted than what we define as
> information? Or perhaps the role of electrical communication is more
> along the lines of "a synergist"? Something doesn't need to be
> big to be potent.

HP: I think what you mean is, What if our model does not represent what's
really going on? That is always a possibility, but then we expect that
eventually the model won't work. The Hertz condition will not be met.

> Another aspect I find intriguing
> is you said "electrical signals are important for rate-dependent
> coordinations" and for activity regarding time in the
> brain... Molecular/chemical activity is dependent on sequencing, isn't
> it? Rate, sequence, duration... all of these are time-related aspects. So
> these two modes are both dealing with different aspects of
> time.

HP: It is true that everything happens in real time, but nevertheless
some things depend crucially on rates of change and other things do not.
For example, all the basic laws of nature depend on (and are 
expressed as) rates of change (time derivatives). By contrast, all formal
mathematics and logic are rate-independent. That is, it makes no
difference in its validity how fast you can prove a theorem. Computers
will compute the same function no matter at what rate the CPU works.
Similarly, the sequence of amino acids in protein synthesized under
genetic control does not depend on the rate of synthesis (within wide
limits). The meaning of the text you are now reading does not depend
strongly on the rate you read it (again within limits). The left side of
the modeling diagram is rate-dependent (Nature's causal entailments). The
right side is rate-independent (formal inferential entailments). That is
why the observer's choice of encoding that must connect the two sides can
not be entailed by either side.

> Judith: Electrical charge is one
> of the known aspects of atomic organization/behavior as well (is it an
> ingredient or an effect?)... Hmmmmm....... 

HP: There are intrinsic and extrinsic observables. Mass, charge, and spin
are universal intrinsic properties of fundamental particles. You might
call the intrinsic properties the permanent "ingredients" that
define the type of particle. Their position and kinetic energy are
extrinsic properties that define the state that will change over time
depending on the "effects" of external forces.

End of physics lesson. I hope that helps.

Howard