ScienceWeek

SCIENCEWEEK

New Books & Miscellany in the Sciences

August 22, 2003

Vol. 7 - Number 34C

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Contents:

1. Neuropsychiatry: The Development of Chlorpromazine
2. Neuroscience: A Tour of the Brain
3. Molecular Biology: Reductionism and the Molecules of Life
4. Mathematics and Computer Science: On Cybernetics
5. History of Physics: On the Certainties of Classical Physicists
6. History of Astronomy: On the Discovery of the Planet Uranus
7. New Books and Books Noted

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1. NEUROPSYCHIATRY: THE DEVELOPMENT OF CHLORPROMAZINE

The existence of drugs that can effectively relieve persistent
and disabling forms of mental distress can be traced back to a
series of surprising discoveries that began around 1950. Until
then, psychiatrists had very little interest in drugs. The only
drugs that they regularly prescribed were sedatives, mainly
barbiturates.

Of these the most widely used was phenobarbital (Luminal).
Introduced in 1912 by Bayer, the company that had made its name
by creating aspirin, it was especially popular with doctors in
general practice, who prescribed it in small doses as an all-
purpose psychiatric drug -- an aspirin for the mind. It was also
used extensively by psychiatrists in mental hospitals, who gave
large doses to agitated or unruly patients to put them to sleep,
sometimes for several days.

But despite the extensive use of phenobarbital, there was keen
awareness of its limitations. At best it provides only transient
relief of mental distress, which often returns in full force when
the drug wears off. Furthermore, repeated use gradually produces
adaptive changes in the brain, so that progressively higher doses
are needed to get the beneficial effect. To make matters worse,
some people who are treated with phenobarbital become addicted to
it and begin to use it compulsively. Little wonder, then, that
psychiatrists were not enthusiastic about phenobarbital or the
other sedative drugs of that period, all of which had similar
shortcomings.

Their attitude changed in the i950s with the discovery of a
completely different type of medication. Unlike phenobarbital,
this new drug improves the mental functioning of certain
patients, rather than simply sedating them. Unlike phenobarbital,
the gradual changes in the brain that follow from its repeated
use makes it progressively more effective rather than less
effective. Unlike phenobarbital, it is not addictive. As
psychiatrists became convinced of the great value of this new
drug, and the other drugs that soon followed, they started
dusting off their prescription pads. The discovery of this
remarkable medication depended on a series of lucky breaks. They
were set in motion in the late 1940s by Henri Laborit, a surgeon
in the French navy, when he became interested in the sleep-
inducing properties of an antihistamine called promethazine
(Phenergan). Although sedation is not a desirable property of a
remedy for colds or allergies -- which accounts for the current
popularity of nonsedating antihistamines such as Claritin --
Laborit decided to turn it to his advantage by utilizing
promethazine as an aid in anesthesia. In 1949 he reported this
off-label use of promethazine in a Belgian surgical journal.

Aware of Laborit's research, Pierre Koetschet, assistant
scientific director at Rhone-Poulenc, the French pharmaceutical
company responsible for promethazine, initiated a hunt for
derivatives with stronger sedative effects. On October 3, 1950,
he circulated a memo in which he recommended "chemical work...
that will provide substances with maximal activity... [in]
prolonging the action of general anesthetics." Koetschet's goal
was to find a better promethazine that would be widely used by
surgeons and anesthesiologists.

Based on Koetschet's suggestion, Paul Charpentier, the chemist
who had created promethazine a decade earlier from a smelly tar
derived from coal, began tinkering with its structure. In
December 1950 he made a novel compound, 4650RP, which he
submitted for testing in rats. Having had no reason to believe
that there would be anything special about 4650RP, Charpentier
was excited to learn that the animal tests showed that it is
indeed more sedating than promethazine -- just what Koetschet had
hoped for. Furthermore, the drug seemed sufficiently safe to
justify its use in humans. In April 1951 Rhone-Poulenc made it
available to doctors for testing under its new name,
chlorpromazine.

Rhone-Poulenc's luck did not end with the discovery of the
sedating properties of chlorpromazine. The company also had the
good fortune to give test samples to psychiatrists. In retrospect
this seems like an obvious thing to have done. But in 1951 most
psychiatrists were mainly concerned with the psychological
aspects of mental illness and turned to medications only as a
last resort. It was Laborit's enthusiasm about the many potential
uses of the calming effects of chlorpromazine that encouraged a
few psychiatrists to try it. It was they who made the astonishing
finding that chlorpromazine is much more than a strongly sedating
antihistamine.

Adapted from: Samuel H. Barondes: Better than Prozac: Creating
the Next Generationk of Psychiatric Drugs. Oxford University
Press 2003, p.17. More information at:
http://www.amazon.com/exec/obidos/ASIN/0195151305/scienceweek

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ON THE ETIOLOGY AND TREATMENT OF SCHIZOPHRENIA

The diagnoses of various behavioral disorders are for the most
part made in the absence of defined etiology, and because of this
there is a necessary focus on symptoms rather than causes, and
the diagnostic categories are consequently often ambiguous and
labile. Schizophrenia is a serious mental disease (or complex of
mental diseases) that occurs worldwide with a prevalence ranging
from 0.2% to 1%. Its chief characteristic is a chronic impairment
of function involving disturbances of thought, perception,
feelings, and behavior, particularly the appearance of the
classical psychotic symptoms of delusions, hallucinations, and
logic dysfunction. A major worldwide mental health problem,
schizophrenia has been the focus of an enormous number of
research studies during the past century, and nearly every
possible etiology has been proposed to explain its pathogenesis,
including genetic mutations and viruses.

The following points are made by A. Sawa and S.H. Snyder (Science
2002 296:692):

1) Most psychiatric disorders are classified as complex in origin
-- i.e., they cannot be easily explained by a single genetic or
environmental component. One of the most debilitating of these
disorders is schizophrenia, which affects approximately 1% of the
population. Once the symptoms of schizophrenia occur (usually in
young adulthood), they persist for the entire lifetime of the
patient and are almost totally disabling.

2) How do we define schizophrenia? In the absence of a known
molecular abnormality, the diagnosis is based on the simultaneous
presentation of two types of symptoms that reflect a psychotic
disturbance: "positive" symptoms that include delusions,
hallucinations, and bizarre thoughts, and negative symptoms that
include social withdrawal with affective flattening, poor
motivation, and apathy. Patients with affective disorders such as
bipolar disorder may exhibit a subset of the psychotic symptoms
associated with schizophrenia, such as hallucinations, but these
disorders generally have a distinct constellation of symptoms and
familial incidence (1).

3) Efforts to identify the underlying disturbances in
schizophrenia are currently focused on three general lines of
inquiry: (i) examination of the mechanism of action of the drugs
that alleviate the symptoms of schizophrenia, (ii) examination of
neuroanatomical abnormalities in the brains of schizophrenia
patients, and (iii) examination of candidate genes that confer
susceptibility to schizophrenia.

4) There was no truly efficacious treatment for schizophrenia
until the early 1950s, when the beneficial effects of
chlorpromazine were discovered. This drug revolutionized patient
treatment: Besides calming down hyperactive patients, it
ameliorated the positive symptoms of the disorder, enabling
patients to leave mental hospitals and function moderately well
in society at large. Chlorpromazine and its successor drugs were
designated "neuroleptics," from the Greek term meaning "to clasp
the neuron." This designation was based on the pioneering work of
Jean Delay and Pierre Deniker, who observed that the effective
dose of chlorpromazine varied widely among patients. Beneficial
responses generally occurred at doses that elicited neurologic
side effects resembling Parkinson's disease. Parkinson's disease
is associated with degeneration of dopamine neurons that project
to the caudate putamen of the brain. Through studies of dopamine
turnover and direct measurements of dopamine receptors, it was
established that neuroleptics block the D2 subtype of dopamine
receptor (2, 3). Blockade of receptors in the caudate putamen was
found to cause the neurologic side effects of the neuroleptics,
and blockade of receptors in limbic areas such as the nucleus
accumbens and prefrontal cerebral cortex of the brain -- which
regulate emotional behavior -- was found to account for the
antipsychotic effects of the drugs. Administration of
amphetamines, which act by releasing dopamine, was found to
exacerbate schizophrenia symptoms. These drug effects led to a
"dopamine hypothesis" for the modulation of schizophrenia
symptoms, with excess dopamine accentuating and decreased
dopamine alleviating the symptoms (2-4). Although the great
majority of neuroleptics relieve only the positive symptoms of
schizophrenia, clozapine also relieves the negative symptoms and
can cause substantial improvement in patients who fail to respond
to other neuroleptics (5). The great success of clozapine led to
the development of several "atypical" neuroleptics whose
pharmacologic profile resembled that of clozapine.

References (abridged):

1. N. C. Andreasen, Neuron 6, 697 (1996)

2. I. Creese, D. R. Burt, S. H. Snyder, Science 192, 481 (1976)

3. P. Seeman, T. Lee, M. Chau-Wong, K. Wong, Nature 261, 717
(1976)

4. A. Carlson, Neuropsychopharmacology 1, 179 (1988)

5. H. Y. Meltzer, in Psychopharmacology: The Fourth Generation of
Progress, F. E. Bloom, D. J. Kupfer, Eds. (Raven, New York,
1995), pp. 1277-1286

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2. NEUROSCIENCE: A TOUR OF THE BRAIN

The easiest way to make sense of the structure and organization
of the human brain is to look at the way the brain develops in
the embryo, and at its evolutionary history. In vertebrates,
including ourselves, the nervous system starts as a midline
groove in the surface layer of cells on the back of the embryo.
This groove becomes deeper, and soon forms a thick-walled tube
which separates from the surface, and is destined to form the
brain and spinal cord. As the embryo develops, the front end of
the tube, which is closed, swells into three connected vesicles
which will form the forebrain, the midbrain and the hindbrain,
respectively. Later the forebrain divides into an expanded
endbrain, and a between-brain that lies between the endbrain and
the midbrain. The way these different regions develop, and the
functions they have is different in the different classes of
vertebrate but there is a common overall pattern.

You can get some idea of the evolution of the brain -- from fish,
through amphibia and reptiles, to mammals -- by comparing the
brains of animals living today. The striking thing in this
evolutionary series is the progressive enlargement of the
endbrain. In all four classes it develops to form two cerebral
hemispheres, but these are small and fused in the fish, larger in
amphibia and reptiles, and very large in mammals, particularly in
primates. In humans, the cerebral hemispheres are so large that
they fill most of the space in the skull. This great increase in
size is accompanied by the takeover of roles that in lower
vertebrates are performed by other parts of the brain, and by the
appearance of behaviour of a complexity not seen in lower
vertebrates.

The surface of the cerebral hemispheres is a crumpled sheet of
neurons and supporting cells from 2 to 5 mm thick. This sheet is
the cerebral cortex, and the many folds and fissures increase the
effective area nearly threefold. Underlying the cortex are masses
of axons, which, being mainly myelinated, look white in contrast
to the "grey matter" of the cortex. A very large bundle of axons
-- the corpus callosum -- crosses from one hemisphere to the
other, and provides the main pathway for the transfer of
information between the two hemispheres.

Deep within the white matter of each hemisphere are three further
collections of neurons and supporting cells, the basal ganglia,
the hippocampus (from a fanciful resemblance of its shape, in
cross-section, to a "sea horse" -- hippokampos in Greek) and the
almond-shaped amygdala (from the Greek word for almond). The
basal ganglia are largely involved in the control of movement --
it is their malfunctioning that causes the rigidity and tremor in
Parkinson's disease. The hippocampus and amygdala, together with
other structures play a vital part in memory and emotion.

The total surface area of the cortex is about a quarter of a
square metre -- a little larger than a large pocket handkerchief
-- and it contains something like 100 billion neurons. It is
almost certainly to this extraordinary structure, more than to
any other part of the brain, that we as a species, owe our
remarkable intellectual abilities.

The between-brain shows nothing like the same expansion in the
course of evolution. In all vertebrates, during the embryological
development of the between-brain, an outgrowth on each side
develops into the retina of the eye and the optic nerve. A
conspicuous feature of the mammalian between-brain is the
presence, in each side wall, of a large mass of neurons called
the thalamus -- the Latin form of a Greek word meaning "inner
room".

A consequence of the takeover of functions by the cerebral cortex
is that, in mammals, information about all sensations has to be
carried to the cortex. Some information about smell passes
directly from the olfactory organs to a part of the cortex, but
information from all the other sense organs (and also information
from other parts of the brain) reaches the cortex almost
exclusively via one or other thalamus. Each thalamus therefore
acts as a great relay station, but this cannot be its sole
function as there are even more nerve fibres carrying information
from the cortex to the thalamus than there are carrying
information from the thalamus to the cortex. The role of these
back connections is not known, but a fashionable hypothesis is
that they make it possible for the cortex to use representations
of information it has just received, to select signals from the
thalamus that are most likely to be useful for subsequent
cortical processing.

In the floor of the between-brain are several collections of
neurons that together forms the hypothalamus -- hypo being Greek
for below. The hypothalamus is tiny, but by controlling the
pituitary gland, which secretes hormones that influence other
hormone-secreting glands, it dominates the entire hormonal system
in the body, and has important effects on metabolism, growth and
various processes involved in reproduction. It also acts through
the autonomic nervous system -- a discrete part of the nervous
system that, as its name suggests, controls events in the body
that occur more or less automatically, though not necessarily
unconsciously. Of this part of the nervous system, one division
(the para-sympathetic nervous system) is concerned with
"housekeeping" functions such as appetite, thirst, salt and water
balance, body temperature, the movements of the gut and the
emptying of the bladder. The other division (the sympathetic
nervous system) is continuously concerned with the control of
blood pressure, but it is particularly active when the body has
to be prepared for vigorous action. As generations of medical
students have been taught, it is the system for "fright, flight
and fight". Yet another role of the hypothalamus is to act with
other parts of the brain in controlling sleep and wakefulness,
and in producing some of the physical changes in the body that
are normally associated with emotions such as fear, anger or
pleasure.

Adapted from: Ian Glynn: An Anatomy of Thought: The Origin and
Machinery of the Mind. Oxford University Press 1999, p.164. More
information at:
http://www.amazon.com/exec/obidos/ASIN/0195158032/scienceweek

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ON BRAIN SIZE

The following points are made by R.M. Sayfarth and D.L. Cheney
(Proc. Nat. Acad. Sci. 2002 99:4141):

1) An intriguing question in neurobiology is: "Why do primates
have such big brains?" Across the animal kingdom, brain size
increases with increasing body size. Despite this common scaling
principle, however, brain size to body weight ratios differ from
one taxonomic group to another (2). In primates, for example, the
brains of apes are generally larger relative to body weight than
the brains of monkeys, whereas the brains of monkeys are larger
than those of prosimians (2). Structural differences are also
apparent. In chimpanzees, a larger proportion of the brain is
devoted to neocortex than in monkeys, who in turn have
proportionately more neocortex than prosimians (3, 4). Within the
neocortex, ape (and especially human) brains have a particularly
enlarged prefrontal cortex, an area known to be involved in many
forms of abstract thought and rule learning (5, 6).

2) Increases in the size of primate brains have come despite the
fact that brain tissue is metabolically very costly. What
selective pressures have overcome these costs? When the question
is applied to humans, answers typically refer to the adaptive
advantages of technology (initially, stone tools) and language.
But monkeys and apes use only rudimentary tools and lack language
entirely, yet their brains are significantly larger than those of
similar-sized mammals. Some other selective pressures must be at
work.

3) Among primates, relative brain size (corrected for body
weight) is greater in species with larger home ranges and greater
in species that are fruit-eating or omnivorous than in species
that eat leaves. Species that feed on fruit may face special
problems in learning and memory because they depend on widely
spaced food that is ephemeral in both space and time. In contrast
to this "ecological" explanation of brain evolution, others
suggest that primate brains have evolved primarily to deal with
social problems. Primates, they argue, live in relatively large
groups where an individual's survival and reproductive success
depends on its ability to manipulate others within a complex web
of kinship and dominance relations. In recent years this "social
intelligence" hypothesis has received some of empirical support.
The purported link between brain size and ecological or social
intelligence is, however, entirely conjectural. We may assume
that memorizing the location of ripe fruit or remembering the kin
relations of ones' opponents demand considerable brainpower, but
this assumption is neither supported nor refuted by any widely
accepted evidence. Perhaps more important, the "intelligence" of
different species is notoriously difficult to compare. Different
species manifest their intelligence in different ways, making it
almost impossible to find an objective measure of intelligent
performance that can be used across many taxa.

References (abridged):

2. Jerison, H. (1973) The Evolution of the Brain and Intelligence
(Academic, New York).

3. Martin, R. D. (1990) Primate Origins and Evolution: A
Phylogenetic Reconstruction (Princeton Univ. Press, Princeton).

4. Passingham, R. E. (1982) The Human Primate (Freeman, Oxford).

5. Deacon, T. (1992) The Symbolic Species (Norton, New York).

6. Miller, E. (1999) Neuron 22, 15-17.

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3. MOLECULAR BIOLOGY: REDUCTIONISM AND THE MOLECULES OF LIFE

Is life mere molecules, acting together with awesome but in
principle explicable complexity? Or is something more involved?
We simply do not know. Scientists take a bottom-up approach,
assuming the minimum and invoking only testable hypotheses.
Whether this will eventually lead to a point beyond which science
is powerless to proceed, we cannot yet say. But no such point has
so far become apparent. It seems possible that life -- which we
might loosely define as an organism that can reproduce, and
respond to and extract sustenance from its environment -- may be
nothing but molecules and their relationships. Indeed, this seems
extremely likely. It need not be disappointing; quite the
contrary, it would be remarkable. That a conspiracy of molecules
might have created King Lear is a possibility that makes the
world seem an enchanted place.

I do not think it likely, however, that the human mind (let alone
the wonders it concocts) will ever be explained in molecular
terms, any more than Lear is explained by the alphabet. Most
scientists do not believe so either. Phenomena are hierarchical:
all things cannot be understood by considering only what
transpires on a single rung. No matter how well I understand the
way a transistor works, I will not be able to deduce from this
knowledge why my computer crashes. If I sow seeds that fail to
grow, I will do better to begin by thinking about the nutrient
content, humidity, and temperature of my soil than by performing
a generic analysis of the seeds. Much of the skill in doing
science resides in knowing where in the hierarchy you are looking
-- and, as a consequence, what is relevant and what is not.

It is worth spelling this out because a molecular view of biology
is often branded as reductionistic -- as an attempt to explain
every aspect of life at the molecular level of genes. This is
indeed sometimes the best way to proceed, for molecules are after
all the smallest functional units on which life is founded. But
if we accept, as most scientists do, that by descending the
ladder to the microworld we must forgo a whole range of questions
and answers about life (such as: what is consciousness?), then
there seems to be nothing obviously objectionable about the
descent.

Indeed, this path has led us to a clearer understanding of our
fundamental nature. Molecular biology has helped to fill the
major gap in Charles Darwin's evolutionary theory: the issue of
the mechanism of natural selection. It has given us at least some
inkling of how life came into being on a planet of gas, rock, and
water. It has saved lives and relieved much pain and suffering.
It has helped us to understand why medicines do not always work
as we might hope, why irresponsible use of antibiotics has bred
superbugs, how the AIDS virus does its terrible work. The study
of life's molecules became the major science of the twentieth
century's second half, and looks set to have an ever greater
impact on our lives in the future. It is perhaps the one area of
science in which some degree of knowledge is no longer a luxury.

Adapted from: Philip Ball: Stories of the Invisible: A Guided
Tour of Molecules. Oxford University Press 2001, p.41. More
information at:
http://www.amazon.com/exec/obidos/ASIN/0192803174/scienceweek

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PARTICLE PHYSICS: AN EXCHANGE CONCERNING RELEVANCE

In general, "reductionism" is the idea that macroscopic phenomena
can be explained in terms of microscopic entities and/or events,
but the specific meaning of the term depends upon context and the
conceptual identification within a particular science of levels
of understanding. In biology in general, for example,
"reductionism" is the term applied to attempts to explain
biological phenomena in the language of physics and chemistry. In
neurobiology, the term "reductionism" may be applied to attempts
to explain human cognitive behavior in terms of the behavior of
nerve cells and their connections. In evolutionary biology, the
term "reductionism" may be applied to attempts to explain the
dynamics of evolution in terms of molecular genetics. In physics
and chemistry, the term "reductionism" may be applied to attempts
to explain the macroscopic behavior of physical or chemical
systems in terms of events at the level of atomic phenomena. Also
in physics, the term "reductionism" may be applied to attempts to
explain both the macroscopic behavior of a physical system and/or
the microscopic atomic behavior of the entities of the system in
terms of events at the still more microscopic level of
fundamental particles and fundamental forces.

The various sciences are split by scientists (not by nature) into
various levels of explanation, with researchers working at the
various levels using various techniques and concepts. Ordinarily,
in the practice of science, the working scientist does not spend
much time cogitating about whether a general reductionist
approach is useful or not useful, philosophically valid or not
valid, or whatever. The attitude essentially is that here is a
house, I choose to study in detail the nature of the bricks, you
choose to study in detail the nature of the construction of the
house, I enjoy what I'm doing, you enjoy what you're doing, and
each of us is making some contribution to a general understanding
of the nature of the entity "house". This division of labor has
been quite fruitful in science, and there is never much of a
problem concerning the existence of various levels of
investigation until the person who studies bricks says that what
he or she is doing is more important than what the person who
studies the construction of the house does, or when the person
studying the construction of the house says it is the study of
the construction of the house that is more important than the
study of bricks. From the standpoint of "nature", from the
perspective of the giant star *Betelguese, for example, a
relatively nearby stupendous and violent supergiant star
apparently 400 to 500 times the diameter of our Sun, any serious
bickering on the planet Earth about the relative merits of
various levels of understanding in science begins to smack of
farce. But science is a human enterprise, and occasionally the
bickering about reductionism and levels of understanding does get
serious and does occupy attention.

In 1996, in a most prestigious physics journal (_Reviews of
Modern Physics_), the physicist Robert Cahn stated that particle
physics is essential to the understanding of our everyday world,
that "particle physicists construct accelerators kilometers in
circumference and detectors the size of basketball pavilions not
ultimately to find the *t-quark or the *Higgs boson, but because
that is the only way to learn why our everyday world is the way
it is... Given the masses of the quarks and *leptons, and nine
other closely related quantities, [the current theory of particle
interaction] can account in principle for all the phenomena in
our daily lives."

In July 1998, in the journal _Physics Today_, Pablo Jensen, a
condensed matter physicist, took issue with Cahn's views and
suggested that Cahn's "reductionist vision seems to be shared by
many other particle physicists." Stating that he wished to
"reopen a debate in the physics community," Jensen made the
following points: 1) The reductionist ideas of Cahn and other
reductionist particle physicists are wrong: even if we knew all
the "fundamental" laws, we could not say anything useful about
our everyday world. Our everyday world is irremediably
macroscopic, and macroscopic concepts are needed to understand
it. 2) Contrary to the pretensions of particle physicists,
science is organized in decoupled layers, each with its own
elementary entities or concepts, which generally are not simply
derived from those of the lower level but constructed in creative
efforts... Particle physics is practically irrelevant to
understanding our everyday world... "If we learned tomorrow that
previous results and analysis had overlooked certain systematic
errors, and that the t-quark mass is near 195 *GeV and not 175
GeV, it is particle physics that would have to adjust to remain
in agreement with the rest of physics, and not vice versa." 3)
Considering, for example, the property of *chirality of large
molecules (e.g., a sugar or any biological molecule), for all
practical purposes, such molecules do not show the symmetry
expected from the fundamental laws  -- in this case, quantum
mechanics. 4) In the study of phase transitions, there are
characteristics of such transitions that apparently depend on the
collective behavior of the system and are not determined by the
microscopic interactions. 5) Each level of complexity must be
studied with its own instruments, and requires the invention of
new concepts adapted to describe and understand its behavior...
Intermediate concepts such as *entropy, *dissipative structures,
cells, genes, etc., cannot be simply "deduced" from the
fundamental laws: such concepts are said to be "emergent" because
they arise at high levels of complexity and must be invented at
those levels to deal with specific situations... These emergent
concepts are as real and as fundamental as the concepts and
particles introduced by particle physicists. The author
concludes: "By all means let us each study our chosen "layer" of
reality, whether it involves quarks or convective cells. But let
us also remember that each layer is just one part of the greater
whole. Accounting for all the phenomena in our daily lives *in
principle* is entirely different from accounting for them in
actuality."

In the November 1998 issue of _Physics Today_, Robert Cahn
presents a rebuttal to the critique of Pablo Jensen, the author
making the following points: 1) The empirical parameters of the
*Standard Model of particle physics shape the most familiar
aspects of our physical surroundings... Given *these parameters,
the Standard Model, which subsumes the Maxwell and Schroedinger
equations, determines all the fundamental processes of
*electroweak and strong interactions. Changes in the basic
parameters would produce worlds quite different from our own. 2)
The stuff of daily life is made just of electrons and the
lightest quarks. However, we cannot understand these particles by
themselves, because they are intimately connected to others
accessible only in high energy collisions. 3) Concerning the
supposed irrelevance of particle physics, constructs that embody
the essential physical features of complex systems are
indispensable, but their success is not a reason for abandoning
the search for basic physical laws. 4) Nature is not neatly
partitioned into autonomous layers, as Jensen suggests. On the
contrary, the macroscopic makes manifest the microscopic... The
gross properties of the materials around us, their color,
conductivity, and strength, reflect the details of their quantum
mechanical states. Likewise the structure of atoms reflects
divisions in the subatomic world... "Only by willfully closing
our eyes can we miss the connection between the fundamental
interactions and their manifestations that surround us." The
author concludes: "We particle physicists share with all
physicists the goal of explaining the world. We differ by asking
ever more basic questions. Like young children who relentlessly
insist, Why?, particle physicists ask, Why is there light? Why
are electrons light and protons heavy? Why are there electrons or
protons, anyway? 'Just because' and 'Who cares?' will not satisfy
the curious child, nor should they satisfy us."

The same issue of the journal includes a number of letters on the
subject from other physicists, and in one of these letters Paul
Roman suggests that perhaps the motivation for the debate is that
the physics research "grant pie is shrinking while the number of
pie-hungry individuals is still increasing." Perhaps that is so,
and perhaps that is also the motivation behind debates concerning
the reductionist approach in other sciences. But perhaps such
motivations are also part of science as a human enterprise.
Meanwhile, the enormous furnace of Betelguese continues to roar.

R.N. Cahn (Lawrence Berkeley Natl. Lab., US) (Rev. Mod. Phys.
1996 68:951) QY: Robert N. Cahn, Lawrence Berkeley National
Laboratory, Berkeley, CA US

P. Jensen (Claude Bernard University, FR) Particle physics and
our everyday world. (Physics Today July 1998) QY: Pablo Jensen,
Claude Bernard University, Villeurbanne FR)

R.N. Cahn (Lawrence Berkeley Natl. Lab., US) "Particle physics
and our everyday world": A reply (Physics Today November 1998)
QY: Robert N. Cahn, Lawrence Berkeley National Laboratory,
Berkeley, CA US

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Notes:

Betelguese: Also known as Alpha Orionis. It is the 10th brightest
star in the sky, with a luminosity 5000 times that of the Sun,
with an estimated distance of 400 light years. Some astronomers
believe its distance is 1400 light years, which would make its
luminosity 50,000 times that of the Sun. The star is a variable,
its size swelling and contracting with a period of several years.

t-quark: (top-quark) A quark is a hypothetical fundamental
particle, having charges whose magnitudes are one-third or two-
thirds of the electron charge, and from which the elementary
particles may in theory be constructed. A t-quark is one of the
types of quarks and has an electrical charge of +2/3.

Higgs boson: Higgs fields (named after Peter W. Higgs, University
of Edinburgh, UK) constitute a set of fundamental theoretical
fields that induce spontaneous symmetry breaking. In general,
spontaneous symmetry breaking occurs in systems whose underlying
symmetry state is unstable. A Higgs particle is associated with a
Higgs field in the same way that a photon is associated with the
electromagnetic field. Higgs bosons are massive mesons whose
existence is predicted by certain theories. Mesons are apparently
composed of quark and anti-quark pairs; they are produced by
various high-energy interactions and decay into stable particles.

leptons: Leptons are a class of point-like fundamental particles
showing no internal structure and no involvement with the strong
forces. There are 6 leptons: the electron, the muon, the massive
tau lepton, and a specific neutrino associated with each of the
former (3 neutrino "flavors").

GeV: (Gev) Also written as Bev, a billion electronvolts. An
electronvolt is defined as the energy acquired by an electron
falling freely through a potential difference of one volt, and is
equal to 1.6022 x 10^(-19) joule.

chirality: In chemistry, chirality is a property of certain
asymmetric molecules, the property being that the mirror images
of the molecules cannot be superimposed one on the other while
facing in the same direction.

entropy: A measure of disorder in a system. 

dissipative structures: In general, a dissipative system is a
system that loses energy by conversion of energy into heat.

Standard Model: In particle physics, the *Standard Model is a
theoretical framework whose basic idea is that all the visible
matter in the universe can be described in terms of the
elementary particles leptons and quarks and the forces acting
between them.

these parameters: The parameters referred to here are the masses
of the quarks, the masses of the charged leptons, the strength of
3 forces, 4 numbers that describe the weak transformations of one
quark type into another, the mass of the *W boson, and the mass
of the Higgs boson.

W boson: Very massive charged particles (+ or -) that convey part
of the weak force between leptons and *hadrons. Bose-Einstein
statistics is the statistical mechanics of a system of
indistinguishable particles for which there is no restriction on
the number of particles that may simultaneously exist in the same
quantum energy state. Bosons are particles that obey Bose-
Einstein statistics, and they include photons, *pi mesons, all
nuclei having an even number of particles, and all particles with
integer *spin.

pi mesons: (pions) Pi mesons are subatomic particles with masses
approximately 270 times the mass of the electron.

spin: In quantum mechanics, "spin" is the intrinsic angular
momentum of a subatomic particle. 

hadrons: Hadrons are particles with internal structure, e.g.,
neutrons and protons.

electroweak and strong interactions: The fundamental forces
comprise the gravitational force, the electromagnetic force, the
nuclear strong force, and the nuclear weak force. The electroweak
interactions comprise the electromagnetic and nuclear weak
interactions, the latter involved in radioactive decay processes.

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4. MATHEMATICS AND COMPUTER SCIENCE: ON CYBERNETICS

The word "cybernetics" is derived from the Greek word for
"steersman", and points out the essential properties of control
and communication.

In some respects cybernetics certainly represents a very old
point of view dressed in a new garb, since its philosophical
forbears are the materialists of early Greek thought, such as
Democritus, and the Mechanistic Materialists of the eighteenth
century. This ancestry is, however, no more than the bare
evolutionary thread of a materialistic outlook, and we are not
primarily concerned here with the philosophical aspects of its
development. It should, indeed, be quite possible for those who
are radically opposed to the Mechanistic Materialists and their
modern counterparts to accept some part of cybernetics for its
methodology and pragmatic value alone.

Cybernetics might be briefly described as the science of control
and communication systems, although it must be admitted that such
a general definition, while being correct, is not very helpful.

Cybernetics is concerned primarily with the construction of
theories and models in science, without making a hard and fast
distinction between the physical and the biological sciences. The
theories and models occur both in symbols and in hardware, and by
"hardware" we shall mean a machine or computer built in terms of
physical or chemical, or indeed any handleable parts. Most
usually we shall think of hardware as meaning electronic parts
such as valves and relays. Cybernetics insists, also, on a
further and rather special condition that distinguishes it from
ordinary scientific theorizing: it demands a certain standard of
effectiveness. In this respect it has acquired some of the same
motive power that has driven research on modern logic, and this
is especially true in the construction and application of
artificial languages and the use of operational definitions.
Always the search is for precision and effectiveness, and we must
now discuss the question of effectiveness in some detail. It
should be noted that when we talk in these terms we are giving
pride of place to the theory of automata at the expense, at least
to some extent, of feedback and information theory.

The concept of an effective procedure springs primarily from
mathematics, in which it is called an "algorithm". It has been an
important mathematical and mathematical-logical question to ask
whether parts, or even the whole, of mathematics is effectively
derivable. Is it possible to derive all theorems of classical
mathematics in a purely machine-like manner? The theorems of K.
Goedel (1906-1978) (1931) and A. Church (1936), and the work of
A. Turing (1912-1954) (1937) on the Turing machine, as it is
called, gave answers to these questions as far as mathematics was
concerned. It was possible to show that all of classical
mathematics could not be reproduced in this manner, although most
of it could. These results have actually led to misinterpretation
outside mathematics, in that they were thought to imply that
there were some mathematical operations that could not be
performed by a machine, whereas they could be performed by a
human being. This is a mistake, and certainly does not follow
from any work done on decision procedures.

What does follow is that, in order to deal with certain
mathematical operations (for example, those involving the choice
of new branches for development), a machine would need to be able
to compute probabilities, and to make inductions. It must
necessarily be agreed, however, that the machine may make some
mistakes in its computations, though we must not overlook the
fact that these are exactly the sort of conditions that would
apply to a human being performing the same operations.

Adapted from: F.H. George: The Brain as a Computer. Pergamon
1962, p.2. More information at:
http://www.amazon.com/exec/obidos/ASIN/0080170226/scienceweek

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5. HISTORY OF PHYSICS: ON THE CERTAINTIES OF CLASSICAL PHYSICISTS

The certainty with which many physical scientists of the 1880s
thought they had the fundamental questions nailed down is today a
source of puzzlement to scholars. At Harvard University, for
instance, the then-head of the physics department, John
Trowbridge, felt compelled to warn bright graduate students away
from physics. The essential business of the science is finished,
he told them. All that remains is to dot a few i's and cross a
few t's, a task best left to the second-rate. In 1894, Albert
Michelson (1852-1931) of the University of Chicago, one of the
most prominent experimenters of the day and the future recipient
of a Nobel Prize, told an audience that "it seems probable that
most of the grand underlying principles have been firmly
established and that further advances are to be sought chiefly in
the rigorous application of these principles to all phenomena
which come under our notice... The future truths of physics are
to be looked for in the sixth place of decimals."

Michelson's timing was comically bad, as it happened. Before the
conference proceedings were printed, the first evidence of the
previously unknown phenomenon of radioactivity was discovered by
one Antoine-Henri Becquerel (1852-1908), the third Becquerel in a
row to occupy the chair of physics at the Musee d'Histoire
Naturelle in Paris. A balding, irascible man with a fierce little
Vandyke beard, Becquerel had spent his twenties and thirties
performing undistinguished experiments on phosphorescent
crystals. He got his doctorate at the age of thirty-five and
almost immediately gave up research, settling into the
comfortable respectability of his professorship. Becquerel was,
to say the least, an unlikely candidate for celebrity; everything
about him suggested that he was destined to be a footnote to
future histories of science.

There are few scientific discoveries whose circumstances are
known as minutely as those around the almost accidental finding
of radioactivity. On January 7, 1896, the great French
mathematician Henri Poincare (1854-1912) received a letter
containing several astonishing photographs of the bones in
someone's hand. The bones belonged to Wilhelm Conrad Boentgen
(1845-1923), a scientist Poincare had never visited. The letter
explained that the pictures had been taken with the aid of a new
discovery, x-rays, that Bontgen had turned up the previous month,
and that he was publicizing his findings by mailing off prints
all over Europe. Publicized they were: The photographs created a
sensation across the globe. Within three weeks, little Eddie
McCarthy of Dartmouth, New Hampshire, became a local cause
celebre when his broken arm was set by physicians armed with x-
ray images of the fracture. It is easy to imagine Poincare's
amazement -- photographs of the inside of a human being! -- and
he quickly asked two local doctors if they could duplicate
Boentgen's work. On January 20, they showed their own x-ray
photographs to the assembled members of the French Academic des
Sciences. The reaction was immediate and extreme. In the next
fortnight, five members of the Academic presented papers on the
new phenomenon.

Becquerel, too, was sitting in the audience when the x-ray photo-
graphs were shown. He was fascinated by the strange ghostly
images and the mysterious emanations that produced them. Both he
and his father had studied the phenomenon of phosphorescence --
the museum laboratory was filled with lumps of stone and wood
that shone in the dark. The glow of x-ray emission put Becquerel
in mind of the light in his study; although he had not done much
active research in the last few years, he thought immediately of
putting some phosphorescent rock on photographic paper to see if
it would darken it in the same way as one of Roentgen's x-ray
sources. It would not be all that much work.

What happened next has been recounted many times: how over the
next month Becquerel tried a variety of phosphorescent stones,
and found nothing; how one day he happened to pick up a chunk of
potassium uranyl sulfate, a messy crystalline mix of uranium,
potassium, sulfur, and other elements, which he knew from
experience glowed under ultraviolet light; how he set the rock
out on his balcony to be charged up by the ultraviolet rays in
the winter sunlight; how he took a photographic plate, wrapped it
up in thick black paper to shield it from the sun, and put it
beneath the uranyl sulfate; and how, to his pleasure, in the
darkroom he saw that the radiation -- he called it "penetrating
rays" -- from the rock had glided through the paper and produced
gray smudges on the plate.

Adapted from: R.P. Crease and C.C. Mann: The Second Creation:
Makers of the Revolution in 20th Century Physics. MacMillan 1986,
p.10. More information at:
http://www.amazon.com/exec/obidos/ASIN/0813521777/scienceweek

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6. HISTORY OF ASTRONOMY: ON THE DISCOVERY OF THE PLANET URANUS

Of the planets visible to the naked eye, Uranus is unique: it had
to be discovered. No ancient people recorded the wanderings of
this dim green world, and the few astronomers who glimpsed it
prior to its discovery thought it was just a faint and
insignificant star.

Ironically, the keen-eyed man who would fish this distant world
out of the celestial sea had little interest in planets. German-
born English astronomer William Herschel (1738-1822) had set for
himself what he saw as a far greater goal, understanding the
stars and the structure of the Milky Way. In contrast, most
astronomers of his time concentrated on the Solar System.
Herschel's training also lay outside the mainstream of astronomy,
for he was a musician who did not delve into science until his
thirties. He taught himself astronomy and built large telescopes
that he deployed to probe the heavens.

Herschel discovered Uranus as he was searching the sky for double
stars, which were one step in his grand scheme to fathom the
Galaxy. On March 13, 1781, between 10 and 11 pm, he noticed a
peculiar object in Taurus the Bull, near its border with Gemini
the Twins. Because both constellations belong to the zodiac, they
periodically give refuge to the Sun's planets. The one that
caught Herschel's attention lay just beyond the tips of the
Bull's horns. Herschel could see that the object was extended
rather than sharp and starlike.

He did not think it was a planet. For millennia, the Solar
System's planetary boundary had been firmly fixed at Saturn, and
the idea that other planets circled the Sun beyond Saturn's orbit
was as alien a thought as a second moon orbiting the Earth.
Herschel therefore believed the peculiar object was either a new
comet or a nebulous star. Four nights later, he reobserved the
object. "It is a comet," he wrote, "for it has changed its
place."

No comet like Herschel's had ever been seen. Wrote French comet
hunter Charles Messier, "I am constantly astonished at this
comet, which has none of the distinctive characters of comets."
The comet had no tail, and it refused to follow the orbit
computed for it. Unlike planets, most comets have extremely
elliptical orbits around the Sun, so astronomers assumed that
Herschel's did, too. Just days after calculating an orbit,
however, astronomers found the comet darting from the predicted
path. Eventually, they realized the reason: this was no comet
pursuing an elliptical orbit but rather a new planet lumbering
along a circular orbit in the outermost reaches of the solar
system. The new planet lay twice as far from the Sun as Saturn;
Herschel's discovery had doubled the size of the known Solar
System.

Strangely, most astronomers recognized this long before Herschel
himself, and months passed until he grew convinced that his comet
was really a planet. Nevertheless, the discovery showered
Herschel with fame, and he named the new planet after the king of
England, George III, who had lost the American colonies, but
thanks to Herschel had gained a whole new world. Unfortunately
for the king, the name did not stick, and the planet is now
called Uranus, the god of the sky, father of Saturn, and
grandfather of Jupiter.

Herschel's discovery had been serendipitous, because he found the
planet while looking for something else. The feat of this amateur
astronomer became all the more remarkable when professional
astronomers realized that their peers had seen Uranus over twenty
times before the discovery but mistook the planet in every
instance for a mere star. The first was John Flamsteed, the
astronomer royal in Greenwich. In 1690, over ninety years before
Herschel's discovery, Flamsteed observed Uranus in Taurus. He
even named the "star" 34 Tauri.

Adapted from: Ken Croswell: Planet Quest: The Epic Discovery of
Alien Solar Systems. Harcourt Brace 1997, p.34. More information
at: http://www.amazon.com/exec/obidos/ASIN/015600612X/scienceweek

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7. NEW BOOKS AND BOOKS NOTED

Travels in Four Dimensions: The Enigmas of Space and Time. Robin
Le Poidevin. Oxford University Press 2003, 275pp. A guide through
some of the most intriguing questions of the Universe -- from
time travel to parallel worlds. The author is professor of
metaphysics at the University of Leeds (UK). More information at:
http://www.amazon.com/exec/obidos/ASIN/0198752547/scienceweek

Cell Biology. T. Pollard and W. Earnshaw. Saunders 2002, 834pp.
The text has a molecular emphasis rather than an emphasis on cell
biology. Based in bioinformatics and protein structure.
Appropriate as an advanced undergraduate or graduate textbook.
More information at:
http://www.amazon.com/exec/obidos/ASIN/0721639976/scienceweek

The Way and the Word: Science and Medicine in Early China and
Greece. G. Lloyd and N. Sivin. Yale University Press 2002, 368pp.
A scholarly study of the investigation of the natural environment
in China and Greece from 400 BC to 200 AD. The authors are noted
historians. More information at:
http://www.amazon.com/exec/obidos/ASIN/0300092970/scienceweek

Remembering Trauma. Richard J. McNally. Harvard University Press
2003, 430pp. An analysis of the evidence for each side in the
debate concerning how trauma is linked to memory. A synthesis of
research from clinical psychology, cognitive neuroscience, and
developmental psychology. The author is a psychologist at Harvard
University. More information at:
http://www.amazon.com/exec/obidos/ASIN/0674010825/scienceweek

Edwin J. Cohn and the Development of Protein Chemistry. Douglas
M. Surgenor. Harvard University Press 2002, 434pp. The story of a
man and a research group that saved countless lives in war and
peace, how the dynamic Edwin J. Cohn transformed from a
laboratory chemist to the manager of a vast wartime effort that
became a small Manhattan Project. More information at:
http://www.amazon.com/exec/obidos/ASIN/0674009622/scienceweek

Skeletal Muscle: Pathology, Diagnosis, and Management of Disease.
V. Preedy and T. Peters (eds). Greenwich Medical Media 2002,
716pp. An attempt to present an integrated approach, but the book
is neither an introductory textbook nor detailed enough to be of
interest to basic scientists. More information at:
http://www.amazon.com/exec/obidos/ASIN/0841100293/scienceweek

Form and Function in the Honeybee. Lesley Goodman. International
Bee Research Association 2003, 220pp. A synthesis of honeybee
sensory physiology and functional morphology. Both visual treat
and at the same time a rigorous scientific monograph. The author
was a noted researcher. More Information at:
http://www.ibra.org.uk

Echo of the Big Bang. Michael Lemonick. Princeton University
Press 2003, 232pp. A journalist's view of the people and results
of the NASA Wilkinson Microwave Anisotropy Probe (WMAP). The
human element in science well illuminated. More information at:
http://www.amazon.com/exec/obidos/ASIN/0691102783/scienceweek

Decisions, Uncertainty, and the Brain: The Science of
Neuroeconomics. Paul W. Glimcher. MIT Press 2003, 375pp. The
author is a neuroscientist at New York University (US). This is
the first full-length book in the new field of neuroeconomics. A
provocative attempt to present a neurobiologically based model of
economic behavior. More information at:
http://www.amazon.com/exec/obidos/ASIN/0262072440/scienceweek


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