When Claude Shannon used
the word 'entropy' to describe a unit of measurement that could compare
signal-to-noise ratios in different channels, by how much was he relying on the
previous thermodynamic understanding of the word? Either he knew he was
inverting the meaning or he considered the two meanings to be at some deeper
level one and the same (ignoring the non-starting possibility that he simply
didn't understand physics). To solve this problem, it is unfortunately
necessary to swim deeply into the history of entropy and its various
formulations, most notably by considering that the definition differs itself
when considered by statistical mechanics or by thermodynamics, which is as much
to say that the word was already a complex word by the time of the publication
of 'A Mathematical Theory of Communication' (Shannon, 1948).
Thermodynamics
concerns itself with the generalized energy potential of homogenous fields of
matter in any state. Though fields can be broken down into smaller and smaller
units, potentially to the sub-atomic level and beneath, it is not necessary to
account for the motions of each and every unit in the field; rather, the
potential energy can be indirectly inferred through Gibbs' formula utilizing
the Boltzmann constant 8.3144598(48) J*mol-1*K-1.
Frightening as this may appear, it is simply a mathematical pseudo-constant
that is always true regardless
neighbour-girls,
whose phone has lost its electricity, in the next room, calling the phone
company, will they let themselves out? so now
regardless of where in the universe you happen to be.
We
should speak more about Shannon, an interesting person in his own right, who is
known as the founder of information theory. Born in
During
the Second World War, Shannon applied his genius to cryptology and other
fields, most notably (and unpredictably) in fire-control, and it was in
fire-control that he engineered the breakthrough we are most interested in
here, namely, his formalization, using symbolic logic, of the problem of noise
in channels, intending on getting at a method of accurately predicting the
truth of any medium‑which led, as mentioned above, to the famous 1948
paper that he published in 1948. In his A Mathematical Theory of Cryptography
(1945), he wrote: "We suppose that the possible messages of length N can
be divided into two groups, one group of high and fairly uniform probability,
while the total probability in
a phone
company technician along with his apprentice, telling me none of the phones in nbrhd work, almost blaming me cuz
my line's the faulty one they think, down in the basement with sensors at
walls, neighbour-girls now in kitchen making coffee for all
in the second group is small. This is usually
possible in information theory if the messages have any reasonable length."
Now
consider: how did
Returning
to
one's yelling hey! and I
can't describe the noise, I dash into the basement past my coffee-drinking
neighbours who don't lift a finger, I hear water because the phone guys have
drilled into a pipe, they're pulling wall away and plugging saying, It's
nothing we'll have it all back together in no time, we'll call city, and a city
guy shows up to shake his head
is a message and another piece of information
is not? Recalling that almost anything can be a channel‑even a channel of
water or a water pipe‑and that it can carry information possibly even in
the form of small origami boats, we see that noise can be caused by, say, a
leak in the pipe that introduces interference (though in the electrical world
the interference can come from the channel in the form of heat-loss) and that
this is precisely what the notion of 'noise' implies.
And now there's dogs barking, many dogs outside and someone's
banging, banging, banging to the door and there's a woman walking seven dogs
who says there's smoke billowing out my basement window; and sure enough there
it is puffing out like some Victorian ocean-liner; I go in and she follows me
for no good reason, with the dogs barking; I pass my neighbours who are
laughing and down in the basement to say there's smoke out the window; they
laugh!
considered a twenty-seventh character, and the ensuing
half-century has proved his intuition true: the addition of 4% reduced
ambiguity (and noise) by 23% according to research (currently unavailable).
Nonetheless,
it is currently understood that Message through Channel is inhibited by
anything that can be called Noise, and that Noise in a Channel can be measured
in all kinds of ways which we will get to soon enough, maybe in Chapter Two or
Chapter Three. This introductory chapter is more interested in how water
escapes from pipes and how smoke emerges from windows, i.e. the creation of
noise that emerges from the signal itself, absenting the fact that damage to a
channel can be from an external source‑consider electromagnetic
interference to a pacemaker that's meant to rpevent
someone from suffering from sever heart
There's another knock at the door and the dogs go crazy in the
kitchen, I go to the door and I recognize who it is, it's my cousin Bernie and
his wife and their son and Bernie tells me their car broke down a block away
and What a Coincidence they have to call for car help (mentioning some smoke
they saw) so I explain crazily then get them into the living room and the dogs
and drills and laughter are all over the house, heavy boots on stairs, the city
guy says he's almost done and the electrical fire's out and I say, "Almost
two-thirds of the way through!"
heart
attack‑thus we have the channel attacked from two sides at once, which
it's no matter which or which it's all the same, noises that interfere with the
signal, and Shannon chose the word noise for just that reason. In the
fourteenth century the loudest noise an ordinary person could ever hope to hear
was the noise of dogs barking. I don't think it was even called noise back
then. Look it up. So anyway, noise, noise:
Claude
Shannon was born in 1916 in Medford, Massachusetts, which was a quiet town. He
was a sensitive child who absolutely hated noise and he became obsessed with it
to such an extent
There seems to be a knocking at the door and I say seems because
the dogs sound to be fighting and what can one expect with seven dogs in a
kitchen?; Bernie yells, "Door!" and I droppitall
and go to the door and it's a woman with a wooden box over her shoulder dressed
nice with a blue pillbox hat and she says Did someone here phone for some Botox injections and I of course say No, come in; and I
wonder where to put her, in the livingroom, kitchen,
even basement, but as we're passing the livingroom my
cousin's wife screams DAPHNE!!! and then they're laughing like it's been a
century; gets the dogs louder yet coincidentally the basement drilling stops
and the three men down there cheer from some success;
extent
that the measurement and reduction of it, (being noisy), was to become his
great heroic goal, to make the rest of us, his people of the future,
unwittingly (for he wasn't some circus freak) into the people of the
Information Age, which is what the present right-now really is, you know? So
the object-lesson here is that you can be doing stuff for one reason and the
result could be something else entirely, something completely unexpected.
Signal-to-noise
ratios, channel-wise, can be expected to remain determinate to a
I get to understand that there's more knocking at the door, as
heard through dog-fights and re-unions and drillings and sandings,
so I go to the door and there I find a young man and a young woman. He is
dressed in a white shirt and black pants and he's wearing a tie; She's in a white blouse and a blue skirt and she's also
wearing a tie. I say, "You're Mormons, right?" and they say,
"Why yes, how did you know?" I say, "Come on in." He starts
forward but she holds him back. He says, "That wouldn't be proper." I
say, "There's plenty of people here. I'm sure
they'd like to meet you." Finally I get them to come inside and I
introduce them to the people in the living-room, the kitchen, and the basement;
I leave them in the living-room. As it turns out, the young man is fond of
dogs.
a
high degree, and a measurable one, you can understand this, I an getting
through despite the noise that comes with the channel of language, I am talking
about it as I am doing it, showing you how an encoding works; in any case, this
channel is carrying thought or sound, one or the other depending on how you
look at it, either what I am
There is a knock at the door and I wonder if the floors of my
house will survive, I wonder if this will go on forever, I wonder how to set
stop to this structure; at the door is a delivery-woman armed with clipboard.
She says she's come from Amazon and that she has six pizzas and a case of
scotch, prepaid; I say I didn't know Amazon sold scotch and she says they don't
and winks. I lead her fleetingly through the
living-room and greetingly into the kitchen where I
point out where the glasses and plates rest expectantly; wonderingly I drop to
the basement: the phone man and the city guys are talking baseball! I say,
"Come up, come up." I can feel the climax incipient, I am not
breathless. Wide with wonder I take me up-the-stairs, whence then I snap back
to the reality of deadline and blush and cough at myself; all my guests are
calamitous and two of the dogs are resting their paws and rabbit-dreaming; I
return to my desk;
am
is the channel or perhaps it is the NOISE or where is the NOISE coming from and
consider music because we don't know what it is or why animals don't care for
it; now how does the attitude of the receiver affact
whatever
I know it's to come and I am ready for it, like a joke's punchline to an audience of one. To the door, to the door;
and I find no less than four. Two men and two women, one of
each carrying black violin cases. I say, "Hello." The man with
the case says, "We are travelling minstrels who have seen many entering
your home. We are here to play for them. This (indicating the woman without a
case) is my girlfriend Annie; and this (the man sans case) is my musical
partner's boyfriend Arnie. May we come in?" "And how!" I reply. I lead them into the
living-room where folks are not surprised by their appearance, as if their
noise called into existence a harmony of the spheres. The workers downstairs
have come up and they are drinking wee drams of scotch; my neighbour-girls
appear like conspirators who orchestrated everything (though I know they did
not); the Mormons are greater than their stereotypes; my cousin and his wife
are chatting up the delivery-woman and the dog-walker. Arnie
and Annie want me to join in the entertainments; I tell them I have to finish
up my Chapter One.
whatever the subject believes they are hearing, how
real is the signal, or is the noise good? Now read my Chapter Two.
Hee-haw, haw-hee, haw-hee, hee-haw squalked
the fiddles in the living-room as tables and chairs moved into kitchen and
stairs.
I go out into the living-room and I see they'd almost all set
themselves out, fiddlers in the corner, one of the neighbour-girls with Arnie, the other neighbour-girl (Daphne) with the boy
Mormon, the phone-man with the delivery-woman, the apprentice with the female
Mormon, the man from the water department with the Botox
applicator, cousin Bernie with his wife, their son with the dog-walker, and
Annie standing, holding out her hand, to make us all into pairs.
"Time for double quadrille," calls the fiddler, and we
make ourselves set
In rectangular formation in separate designations, preparing to
sweat,
An afternoon's festival of noise and the odd contusions
(For my living-room's small when we buck our illusions)
We dance and we dance like we've done it for years
This patterny process of
back-and-forth and up-and-down to the music of the spheres,
Or so we believe of the background radiations
That keep all
the planets upon their foundations,
And here in my house is an echo of that
While we dance in our circles like acrobats,
Whilst singing is heard from afar and away,
Where the signal is noise with a second's delay,
And thus we are dancing, two years and a day.
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