-
KHURSHID AHMAD
Metaphors in the Languages of Science1?
(Appeared in New Trends in Specialized Discourse Analysis. (2006) Eds. Maurizio Gotti &Vijay
Bhatia. Bern:Peter Lang, pp 197-220)
1. Introduction
Scholars in LSP studies have the gift of prescience – the discussions
about the conceptual organization of the terminology of a domain,
started nearly a century ago by Eugene Wüster, have a clear resonance
with the discussions related to ontology in the current literature in distributed computing, especially in the literature on semantic web.
The ever burgeoning web, with texts, images, music and movies, is
searched predominantly using ‘keywords’; search engines have large collections of these words used to index texts (and images) such that a
user can retrieve the indexed texts using the self-same or similar
keywords. The literature on search engine technology has contributions on ontology – literally what there is, a notion that is not
alien to the Wüster tradition: any attempts at the organization of
concepts requires thought about what there is or is perceived to be.
The work in ontology is about creating the conceptual
organization for building term collections and about validating terms
of a specialist domain. LSP researchers have moved on and are now focusing on how texts are organized by the use of terms and
examining the social context of specialist writing. This chapter is
about this move and here I would like to examine the use of metaphor in scientific writing. Linguistic metaphors are used extensively in
science in particular and specialist writing in general. There are two
strands in this chapter: first, a review of work in metaphor studies that
1 This paper is based on three presentations: first, an invited key note speech at
the 11th European Symposium on LSP (Ahmad 1997); second, a selected
presentation at the European Science Foundation Workshop on Metaphors
(Granada 2004); and third a contribution to the 15th European Symposium on
LSP (Bergamo 2005).
-
Khurshid Ahmad 2
focus on the transference between domains through the use of
metaphors, in conjunction with mathematical symbolism and images.
The source domain, to use a term in cognitive linguistics, may be
everyday language or it can be a specialism, and the target domain usually is (another) specialist domain. Second, I will describe how
corpus linguistics methods and techniques can be used in the study of
metaphor in science and technology. My purpose is to draw attention to the edifice of science: there
is no denying that science has improved the quality of life through its
application of principles and practices. There is equally not much
evidence to deny the critics of science that science, or its uses, has de-
humanized human society at large and has created seemingly
unsolvable problems for generations of humans to come. The utility
and horror notwithstanding, scientists show us how language can be used to build a constellation of theories and experimentations, mostly
to satisfy curiosity amongst some human beings. The curiosity then
sometimes leads on to transistor chips, which when incorporated in my computer helped me write this paper; the computer was powered
by energy generated through hydro-electric power or nuclear fuels.
Scientists literally and metaphorically (!) create a world of make-believe through a web of words – some borrowed, some
invented, endorsing self-belief here and suppressing the beliefs of
others there. Consider the tension involved in the use of metaphors in
biology: the positive use of metaphors is reflected in the use of
metaphorical language in molecular biology: the mechanistic
metaphor of information transaction between the macromolecules in animal beings, nucleic acid for instance, or the metaphor of signalling
within biological systems has led to the development of molecular and
evolutionary biology. Biological processes reportedly ‘edit’, ‘transcribe’ and ‘translate’ – these literary metaphors have helped
molecular biologists to communicate amongst their own discipline and
across related disciplines of medicine – pharmacology, for example. Literary metaphors “make extremely complicated molecular processes
intelligible by highlighting their functional components in a human, or
rather semiotic, reference frame. In this case, metaphors have helped
to drive science to new insights” (Chew / Laubichler 2003: 52). The
success of the message-passing metaphor in biology has impacted the
equally ambitious workers in particle physics: there are a number of
-
Metaphors in the Languages of Science 3
‘elementary’ particles that are exchanged between other particles and
thereby help the others to form a bond. These bonds are found in the
nuclei, where protons and neutrons are bound together through the
exchange of so-called mesons. Such exchanges take place through messenger particles “in deference to nomenclature for RNA” (Salam
1990: 39).
The negative, and nefarious, use of metaphors is perhaps best illustrated in the appropriation of scientific terms to describe people:
The extension of genetics to eugenics owed much of its popularity in the
United States and in Germany to its use of culturally resonant metaphors. Labeling people as a burden, a cancerous disease, or a foreign body
(Fremdkörper) conveyed the ‘threat’ to society in terms that people could
relate to in their respective historical and cultural settings. (Chew / Laubichler
2003: 52)
I am interested in the use of metaphors in specialist writing: writing
produced only for an intra-community audience – journal articles and
monographs aimed essentially at an audience that is within a specialism. The use of metaphors in learned writing appears to serve a
different purpose; perhaps, metaphorical language facilitates cohesion
and coherence within a community? Typically, studies of metaphor
are restricted to samples of texts usually published in popular science
magazines (de Beaugrande 1996).
2. Ways of wor(l)d-making
The philosopher Nelson Goodman has his own ways of word-making and for him “metaphor is no mere decorative rhetorical device but a
way we make our terms do multiple moonlighting service” (1978:
104). The multiple moonlighting of terms is evident, for example, in
the use of the term nucleus: in everyday language nucleus refers to a
kernel, in cell biology cells have a nucleus, and in nuclear physics, the
atom has a nucleus. In everyday language, we have nuclear family
and nuclear power, and the derivations of the metaphorical noun – the
-
Khurshid Ahmad 4
adjective nuclear and the verb to nucleate – moonlight in a number of
different subjects. The metaphor moonlighting service perhaps
summarises two or three decades of literature published in the
cognitive semantics on metaphor, where we see a number of terms moonlighting to describe the psycho-linguistic description of the
origins and uses of metaphors. Consider, for instance, the phrase the
great chain of being – which was used in 18th century biology – used in discussing why and how animal metaphors are used in the
description of human behaviour (Kövesces 2002).
The interest in the transition of metaphors from source- to
target-subject matter has been typically discussed in the context of
people’s use of this linguistic device. Recent work here dates back to
Lakoff’s (1987) anti-rationalist approach, which privileges bodily
experience in philosophical analysis. It is assumed that people’s or folk articulation of the possible worlds through language will allow a
deeper view into the workings of the human mind/brain. Indeed such a
position has been taken by pioneering biologists (Mendel) and psychologists (Freud and Jung) whose words have thrown much light
on how the human mind/brain works. A sympathetic interpretation of
the work of Lakoff and his colleagues can be found in Kövesces (2002), which describes three major classes of metaphor: structural,
ontological and orientational metaphors. Structural metaphors “enable
speakers to understand target A by means of the structure of source B”
(2002: 33) – for instance, the passing of time is understood in terms of
the motion of objects. Orientational metaphors “make a set of target
concepts coherent in our [sic] conceptual system” (2002: 35); for example, the concepts of ‘more’ and ‘less’ are explained through the
metaphorical use of ‘up’ and ‘down’ respectively, as in ‘speak up
please’, ‘keep your voice down’. Ontological metaphors are relevant to LSP studies in that such metaphors help us to conceive of our
“experiences in terms of objects, substances, and containers in
general, without specifying further the kind of object, substance or container” (2002: 251).
In the last century, metaphors have been used by scientists to
construct the edifice of both experimental and theoretical sciences.
This borrowing has been finessed by an erudite mathematical
framework. The synthesis of two semes or modes of expression
(linguistic and mathematical symbolism) have led to awe-inspiring
-
Metaphors in the Languages of Science 5
and awesome discoveries. This tradition of synthesising the two semes
– the linguistic seme relying on the use of metaphors to describe
human psychosocial behaviour, ranging from memorising to learning
and from emotions to consciousness, and mathematical symbolism, including logic and statistics – has had a similar consequence in terms
of awe-inspiring large-scale integration of semi-conducting devices
on a chip, nuclear power and remote-controlled devices for aggressive purposes and nuclear weapons. The development of the Internet is
suffused with metaphors that include the single term web and its
interesting, perhaps oxymoronic collocations like the semantic web
and the utilitarian term sets cluster around web services.
An example of metaphorical usage is the assignment of the
attributes of animate beings to inanimate beings. It is often argued that
the rational approach adopted by scientists has led to great discoveries and nowhere is this truer than in physics. The 20th century theories of
matter – the nuclear atom theory and the quantum theory of radiation
– borrow heavily from the terminology of astronomy and (classical, 19th century) physics. Newton’s abiding contribution was to introduce
a mathematical description of how planets moved around a star in the
‘celestial’ universe: the self-same equations could be used to describe the movements of objects on the earth – the proverbial apple falling to
the ground – or the terrestrial universe. The mathematical description
was extended to aquatic systems (a subject called hydrodynamics) and
produced the Newtonian grand unification, with the celestial,
terrestrial and aquatic universes described in one abstract framework
grounded in the notion of force. But the term force as used in modern science has had a difficult birth or rather difficult adaptation by the
community of scientists. The key term force originally referred to
armed men/violence or physical human coercion: a people-centred term requiring vitality and volition was transferred to the target
domain to mean ‘the agency that tends to change the momentum of a
massive body’. Note, the body in question refers to a neuter noun and has no reference to humans. The term energy related to human ‘vigour
of expression’ which, until the late 19th century, referred to vigour of
action or utterance, combines its original people-centred meaning with
the sense that energy is ‘a measure of the system’s ability to work’.
The transfer of animate attributes to inanimate beings and vice-
versa can be illustrated by the recent discussions in computing and
-
Khurshid Ahmad 6
neurobiology related to the twin notions of computers having
intelligence and the brain/mind being essentially a machine. A whole
branch of computing, artificial intelligence, is dedicated to finding
potential mappings between the mind/brain and ‘computer machinery’. Indeed, ‘Computing Machinery and Intelligence’ is the
title of a key paper on the subject by the pioneer Alan Turing in the
1950’s. Turing suggested that (intelligent) computers may play games and may be used in translating from one (human) language to another,
and his prophecy has come true in large measure. There is also a
contrary view: in ‘The Decline and Fall of the Mechanist Metaphor’
(Shanker 1987) the title of the paper comprises metaphorical
expressions in that its source is in history, referring to weaknesses in
the political and military establishments of imperial powers.
The motivation for using human metaphors for inanimate objects, and mechanistic metaphors for animate beings, is explained to
an extent by Feyerabend’s observations about the use of metaphors in
science: “the history of science […] does not just consist of facts and conclusions drawn from facts” but “contains ideas, interpretation of
facts” and “problems created by conflicting interpretations” (1993:
11). He goes on to suggest that scientific education is designed to discount the scientist’s “metaphysics, or his [/her] sense of humour”
such that scientific facts appear “independent of opinion, belief and
cultural background” (1993: 11). The case of the classical physicists
(Isaac Newton, Thomas Young) shows extensive focus on their
personal beliefs, sense of humour and how they borrowed words
established in pre-16th century English and metaphorically deployed
them to construct so-called natural philosophy (our physics).
The question is ‘how does the belief system of a group of
scientists assert itself in what would otherwise be regarded as a purely rational exercise where personal beliefs should play little or no role?’
Consider the metaphor of the planetary system – a star surrounded by
planets executing fixed orbits around the star – which was used to construct the edifice of the nuclear atom: the ‘star’ here was the
nucleus and the (subsequently) discovered electrons were the
metaphorical planets. The electrons executed fixed orbits around the
nucleus and only when electrons ‘jumped’ from one orbit to another
was energy released or absorbed in fixed (Planck’s) quanta of
radiation latterly ennobled as the ‘universal quantum of radiation’ or
-
Metaphors in the Languages of Science 7
h. The population of each orbit was carefully controlled through
properties of matter that only manifest themselves at very small scales
or quantum scales. There is anecdotal evidence that some authors
speculated that since electrons were planets there must be hills, valleys, rivers and seas on individual electrons. The original planetary
system, in turn, is based on Greek mythology and the Judeo-Christian
hypothesis of a helio-centric universe; recall that Galileo had to apologise to the Church of Rome when he declared that the earth was
not really the ‘centre’/star of the universe, but rather belonged to a
planetary system, one of many perhaps in the universe, and again one
of many planets.
Once transferred to the micro-world of atoms and nuclei, the
metaphor of the planetary system was re-transferred to the sub-nuclear
world and this time led to the development of nuclear physics. The question nuclear physicists asked was ‘how is it that the principal
constituents of a nucleus – protons and neutrons – are packed so
tightly in a nucleus?’ The answer proposed by Heidi Yukawa was that there was a nuclear force that was far more attractive than any other
force hitherto known to human beings. Enrico Fermi proposed that
neutrons and protons – so-called nucleons – form orbits in a nucleus, much like the electrons going round a nucleus. So is there something
like a ‘nucleus’ within the nucleus? The ingenious answer was that the
collective effect of the presence of the nucleons creates a virtual
nucleus within the nucleus. Late 20th century physics argues that
protons and neutrons are in themselves composite particles comprising
so-called quarks. In the new physics, the quark metaphor was borrowed partly from Hinduism and Buddhism, and is partly based on
an elusive character in James Joyce’s Finnegan’s Wake – Muster
Mark (Gell-Mann 1994, 1997).
2.1. Lexical inversion and lexicogenesis
Studies in the philosophy of science suggest yet another
transformation of a metaphorical usage of language – a ‘massive
shift’, almost an inversion, in the meaning of a metaphor
(Verschuuren 1986). Take the example of the planetary system again:
Brahe argued that sunrise was caused by the rising sun only to be
-
Khurshid Ahmad 8
contradicted successfully by Kepler who argued that sunrise is due to
a turning earth. When atomic and nuclear physicists borrowed the
planetary metaphor in atomic (and subsequently nuclear) physics, the
meaning of the term atom was inverted from something which was the epitomy of indivisibility to something which was divisible into its
constituent parts. An earlier inversion that established physics as a
subject in its own right, closer to a sub-division of philosophy (natural philosophy to be precise), was the notion of motion. Aristotle thought
that objects move because they have an in-built tendency to do so –
this was contradicted by Galileo, who argued that motion was caused
only when force is exerted on an object.
Lexical inversion, or the denial of an extant concept and its
replacement by a new concept whilst keeping the original term in
place, is a feature of bio-medicine as well. Let us consider one of the central themes in biology and now in medicine – the evolution of
species and its progeny, evolutionary biology. It would appear that the
concept of species is itself a surrogate of a rational construct, but this is not as true as it appears. Some recent discussions in evolutionary
biology about ‘species’ and, in particular, the views of an eminent
evolutionary biologist, naturalist, explorer, ornithologist and historian of science, Ernst Mayr, suggest that the status of the term is under
debate:
The species, together with the gene, the cell, the individual, and the local
population, are the most important units in biology. Most research in
evolutionary biology, […] and almost any other branch of biology deals with
species. How can one reach meaningful conclusions in this research if one
does not know what a species is and, worse, when different authors talk about
different phenomena but use the same word – species? (Mayr 2004: 171)
The lexicogenesis of the term ‘species’ shows how a range of
metaphors were used by the great and the good of biology over the last 300 hundred years or so to revise, refine and sometimes contradict
the extant meaning of the term. For the French biologist Buffon
(1707-1788), to whom the metaphor ‘The Great Chain of Being’ is
sometimes attributed, the notion of species was critical for a
systematic study of a living organism: the biological whole is divided
into classes, classes into genera, and genera into species (c. 1749).
Buffon’s reflection on the biological systems led him in the next 25
-
Metaphors in the Languages of Science 9
years to conclude that species are “a whole independent of number,
independent of time; a whole always living, always the same” (c.
1765). Darwin’s metaphor was ‘The Tree of Life’: species were the
“product of divine creation, and it is this that constitutes their reality”; each species has a species-specific essence – a set of characters which
remain fixed and permanent throughout the duration of its existence,
and which allow it to be captured in a definition. And the Tree of Life had explanatory power because, according to Darwin, “species are
immutable in that they cannot change into other species – varieties are
the limits of species variability”. The debate about species continues
apace and now the metaphor of species is central to conservation and
the ‘species problem’ has to be solved (Stamos 2003: 356).
Ernst Mayr’s 50 years in biology and its related branches shows
an evolution in his understanding of what a species is. In the 1940’s, Mayr (2004) notes that “species are groups of actually or potentially
interbreeding populations which are reproductively isolated”. In the
next 30 years or so he is more comfortable with his definition and drops the hedges ‘actually or potentially’: “Species are groups of
interbreeding populations that are reproductively isolated”. There is
then a shift in his position when 18 years later he observes that “modern biologists are almost agreed that there are real discontinuities
in organic nature, which delimit natural entities that are designated as
species”. Note the use of metaphors of space (discontinuities and
delimitation). In the next three years, Mayr was to re-define species as
“a reproductively isolated aggregate of populations which can
interbreed with one another because they share the same isolating mechanism”. The name of the abstract object – species – remains the
same, some of the basis of the definition is perhaps intact, especially
procreation, but the modern biologist neither invokes a deity nor merely uses the concept of species as a place-holder. Species were
once immutable but now there is a degree of mutation allowed.
2.2. What are metaphors for?
Hoffman (1985) lists 12 functions of metaphors which will help us to
close this section. According to him, metaphors can be divided into
three major categories: (i) metaphors for describing novelty at
-
Khurshid Ahmad 10
different levels of scientific description including hypothesising,
theorizing, conceptualizing; (ii) metaphors used for interpreting extant
theories; and (iii) metaphors for explaining and predicting the
consequences of theoretical concepts and experimental measurements (Table 1).
(a) Novelty
To suggest
new hypotheses, hypothetical concepts, entities, relations,
events, or observations;
new laws or principles; new models or refinements of old ones;
new theories/theoretical systems, or world views; new research methods or ideas for experiments or hypothesis
testing;
new methods for analyzing data;
To give meaning
to new theoretical concepts for unobservable or unobserved events;
To predict new phenomena or cause-effect relations;
(b) Interpretation
To suggest
choices between alternative hypotheses or theories,
(often) choice between more and less fruitful metaphors;
alterations or refinements in a theory;
To contrast theories or theoretical approaches;
(c) Explanation
To provide Scientific explanations in the form of metaphoric redescriptions;
To describe new phenomena or cause-effect relations;
Table 1. The three major categories of metaphor used in science and technology.
We now look at the different uses of metaphor in particle physics and
nuclear physics, two major areas of rational, objective and scientific investigation.
3. Quarks and leptons, parody and subversion: metaphors
and lexicogenesis in particle physics
Twenty-first century physics is concerned with three inter-related
notions: matter, force and energy. This trinity has some resonance
-
Metaphors in the Languages of Science 11
with the ancient Greek’s concern with a quartet of fundamental
entities: air, water, earth, and fire. The ancient Hindus had an octet of
fundamentals: five ‘gross elements’: earth, water, fire, wind and ether
and three ‘manas’: mind, conscience and ego (Prabhavananda / Isherwood 1947: 171-85).
The consolidation of a body of knowledge, now called physics,
relies critically on the metaphor of force. One ‘force’ that surrounds us is gravitational force. This force can be used to explain and to predict
(a) the ordered motion of planets, (b) the ebb and flow in aquatic
systems, and (c) the motion of physical objects on the earth. The term
is metaphorical in that its source is in terms of 17th century concepts
like anima, vis or kraft. It has been argued that the notion of force
actually shows a preoccupation with “the theme of potent, active
principles” (Holton 1973: 58). Einstein has argued that the curvature of space and time in effect determines gravity – the cause of
gravitational force.
The development of quantum theory and nuclear physics took place under the rubric of modern physics in 1887-1946 (cf. Jeans
1950). In this period, two radically new types of forces were
postulated: first, a strong nuclear force, exerted through the agency of mesons; which helps to explain some of the workings of atomic nuclei
– how a nucleus is bound together, for example, and why nuclei
disintegrate. Second, weak nuclear force, which manifests itself when
the atomic nuclei decay/transmute by emitting electrons from within
the nucleus: β-radioactivity, where a nucleus decays by emitting an
electron and a neutrino, shows that the left-right symmetry found to exist in all physical systems is violated during β-radioactivity. The
notion of force in post-modern physics is at considerable variance
with that in Newtonian physics. The strong nuclear force changes its attractive character to a repulsive one at very small distances; in
Newtonian mechanics forces do not change their nature, no matter the
distance. And forces do not ‘conspire’ to violate the fundamental principles of such systems, like for instance preferring the left to the
right. Nevertheless, the term force remains and the metaphor used
initially is preserved in the meaning, in a vague historical sense.
In the 1936-1970 period, physicists could study particles by (i)
examining cosmic ray tracks in photographic emulsions – a shower of
particles leaving tracks in emulsions sent up in balloons or on top of
-
Khurshid Ahmad 12
mountains; and (ii) by building accelerators or atom smashers to study
interaction amongst particles in laboratory conditions – particles were
accelerated to speeds close to that of light and bombarded on a variety
of targets. The reaction products were rich repositories of information. Cosmic rays have helped in the detection of an anti-particle – the
positron, which is an anti of the well-known electron, is a positively
charged electron. Then followed the discovery of the anti-proton, and anti-neutron. When a particle and its anti-particle collided then both
were annihilated and turned into energy. Nature appeared to be
symmetric – for every particle there was an anti-particle; in a few
cases when there were no anti-particles detected or predicted by
theory, the particle was declared its own anti. Very few particles are
stable – protons, electrons and photons are amongst the few; most
other particles decay in less than a billionth of a second! Cosmic rays and accelerators provided a wealth of particles:
mesons, for example, were an intermediate (meso) particle,
intermediate in mass between the ‘heavier’ nucleons and the lighter electrons. There were three kinds of mesons (positive, negative and
neutral pi-mesons) and mesons were fundamentally different from
nucleons and electrons and their antis. Pi-mesons were called bosons – they had an intrinsic property called spin, like all other particles, and
the value of spin was 1. Nucleons and electrons have spin value of ½
and are called fermions. Bosons ‘obey’ Bose-Einstein statistics and
fermions Fermi-Dirac statistics. Pi-mesons were initially called
Japanese electrons and the prefix pi was to distinguish these mesons
from another group of particles (accidentally) named mesons, which were subsequently called mu-mesons; the mu-mesons are fermions,
and are much lighter in mass than the pi-variety.
3.1. Strangeness and flavour in the (particle) zoo
In most of the observations it was found that some particles are
created in pairs; for example, a K-meson or kaon is always produced
together with its anti, and these particles took much longer to decay:
they were called strange particles and a fundamental property of
matter was thought up by physicists – that of strangeness. The number
of particles grew and grew and there was a need to categorise the
-
Metaphors in the Languages of Science 13
growing zoo (an affectionate term actually used in the particle physics
literature) – comprising at one time over 500 particles. Particles were
classified in families: protons and neutrons were classified as
nucleons, then they were subsumed into baryons, which included a number of unstable fermions including sigma, ki, omega, lambda and
delta particles, together with the strange particle hyperon. The other
major class was that of mesons. In addition, there were leptons, of course. Many of the elementary particles were energy peaks found in
various reactions involving other particles – called resonances. These
families in many ways had a Wittgensteinian resemblance: no obvious
unifying factor, except for spins, but they appeared to share nebulous
properties. The family metaphor led to the elementary particle zoo in
the 1960’s: the zoo metaphor was complete with the announcement of
particles births and deaths. ‘Birth’ announcements, still published occasionally in learned physics journals, accompanied the detection of
a fundamental particle in laboratory conditions. The obituaries were
essentially errata sheets announcing errors in the experimental procedure/technique that led to a wrongful report of birth – so that the
particle-that-after-all-was-not-a-particle was declared dead.
Twentieth century physics introduced the notion of fundamental or elementary particles of matter. All matter is supposed to be made
of atoms, a 15th century concept, and we are now told to believe that
all matter is made up of quarks and leptons. During the 1960’s,
Murray Gell-Mann, partially inspired by the eight-fold way of the
Hindus and partly James Joyce, was responsible for the introduction
of the term quark. The post-modern (post 1950’s) physicist does not use sonorous terms like fundamental particle or building blocks of the
universe, but simply refers to ‘elementary units’: quarks and leptons.
And then there are gluons, particles exchanged during interactions between quarks and leptons which ‘glue’ matter. This has led to a new
term, quagma, a composite of quarks and gluon matter; there is a
resonance between the terms magma (in geology) and quagma in particle physics. To sum up, physicists now claim that there are six
different types (or flavours) of quarks and six different leptons. The
six quarks are in turn divided into three generations.
The terminology used by the new physicists (c. 1970 onwards)
had an element of parody and subversion. Gell-Mann, the inventor of
the abiding concept of quark, has suggested that the precedents for
-
Khurshid Ahmad 14
naming conventions, rooted in a ‘pretentious Greek word’ are not very
encouraging. For example, one particle was named after a
hypothesised property which it was deemed to possess but “turned out
later not to be an important property, or even, in some cases, a correct one […] so one might as well invent a zany, relatively meaningless
name, and have fun” (1997: 164). Quarks started life as a purely
mathematical concept (Gell-Mann 1964) used to elaborate certain theoretical constructs in elementary particle physics. Even today there
is a touch of abstractness about this elementary unit, as we are told by
one US government laboratory “While an atom is tiny, the nucleus is
ten thousand times smaller than the atom and the quarks and electrons
are at least ten thousand times smaller than that. We don't know
exactly how small quarks and electrons are; they are definitely smaller
than 10-18
meters, and they might literally be points, but we do not know” (Lawrence Berkley Labs 2006).
3.2. Enter James Joyce in the zoo
These elusive particles appear like characters in a literary fiction text. Gell-Mann unravels this mystery for us:
In 1963, when I assigned the name ‘quark’ to the fundamental constituents of
the nucleon [protons and neutrons], I had the sound first, without the spelling,
which could have been ‘kwork’. Then in one of my occasional perusals of
Finnegans Wake, by James Joyce, I came across the word ‘quark’ in the
phrase “three quarks for Muster Mark”. Since ‘quark’ (meaning for one thing,
the cry of a gull) was clearly intended to rhyme with ‘Mark’ as well as ‘bark’, I had to find an excuse to pronounce it as ‘kwork’ […] [The] phrases [that]
occur in the book are partially determined by calls for drinks at the bar. I
argued, therefore, that perhaps one of the multiple sources of the cry “Three
quarks for Muster Mark” might be “Three quarts for Mister Mark”. […] In any
case the number three fitted perfectly the quarks [which] occur in nature. […]
The recipe for making a neutron or proton out of quarks is, roughly speaking, Take three quarks. (1994: 180-1)
Gell-Mann introduces the term by arguing that “a simpler and more
elegant scheme can be constructed [for classifying elementary
particles – baryons and mesons] if we allow non-integral values for
the charges. […] We then refer to the members u[p], d[own] and
-
Metaphors in the Languages of Science 15
s[trange] of the triplet as ‘quarks’ […] q and the members of the anti-
triplet as anti-quarks q” (1964: 214). He concludes his landmark paper
by noting that “it is fun to speculate about the ways quarks would
behave as if they were physical particles of finite mass (instead of pure mathematical entities as they would be in the limit of infinite
mass)” (1964: 215). Fritzsch further elaborates on Gell-Mann’s choice
of term and suggests that “Joyce’s novel is full of plays on words that are difficult to understand. […] Mr Finn in the novel appears as Mr
Mark, and the three quarks denote the three children of Mr Finn, by
whom he himself is represented from time to time” (1983: 64). And,
in a remarkable leap of the imagination from the novelist Joyce to the
scientist Gell-Mann, Fritzsch concludes: “Thus the association with
particle physics becomes clear. The proton is associated with Mr Finn;
under certain circumstances the proton acts as if it had three quarks’ (1983: 64).
So we now have two basic types of quarks: up-type and down-
type quarks. There are three generations of quarks, each having an up-type and a down-type: up-type quark flavours are up, charm and top;
down-type quark flavours are down, strange, and bottom. Again,
flavour is a fundamental property of ‘matter’ but has nothing to do with the perception of flavour. The lightest flavour is the up quark and
the heaviest is the bottom quark. Most quarks, despite their permanent
‘confinement’ inside baryons or mesons, have been detected
indirectly. Particle physicists have therefore been creating neologisms.
The evolution of species in biology is paralleled in particle
physics by the decoupling of erstwhile elementary particles. The evolution of our universe, according to physicists, from its origin in
time (nearly 10-44 seconds after the Creation) to the formation of
galaxies (about 1013 seconds after the Creation) has led to the
proliferation of building blocks in a universe which itself evolved in
stages. Each stage in the evolution of the universe comprises the
‘decoupling’ of an elementary(?) particle into two particles costing less and less energy; each evolutionary stage is characterised by the
breaking of historical symmetry. The last of the decouplings took
place about 102 seconds after the creation of the universe. Before that
(10-6 seconds after the Creation) there was a quark-nuclear transition
and so on. The fact that all particles were ‘one’ at some distance in
time, about 10-44 seconds after ‘creation’, has led to the notion of
-
Khurshid Ahmad 16
super-symmetry (SUSY), i.e. that bosons and fermions are symmetric:
each boson has a fermion equivalent and vice versa. Each particle has
a super-symmetric partner – the sparticle. The fermions, particles with
spin half, have a postulated bosonic-partner, whose name is built prefixing an s-. The quark has a squark; the lepton a slepton; and the
neutrino a sneutrino. The boson, with spin 1, has a fermionic-partner
with an -ino suffix: the photon has a photino; the gluon has a gluino; the w-boson has a wino; and the z-boson a zino. The boson with spin
zero (known as Higgs-boson) has a shiggs.
3.3. From religion, poetry and heraldry to nuclear physics
Physicists talk about the stability of a nucleus in terms of the number of neutrons and protons within it. In very stable nuclei like helium (2
protons and 2 neutrons), carbon (6 protons and 6 neutrons) and
oxygen (8 neutrons and 8 protons), the ratio is one to one. But there are other, heavier, highly stable nuclei with far greater numbers of
neutrons than protons – 92 protons and 128 neutrons in the lead
nucleus. There appears to be a linear relation between the number of neutrons and protons for ensuring stability. Almost all nuclei have
isotopes – more neutrons than in the more frequently occurring variety
but the same number of protons. Thus carbon-13 (7 neutrons and 6
protons) is unstable and decays spontaneously; the element uranium
only occurs in an unstable form U-238 (92 protons and 146 neutrons)
but its isotopes are even more unstable. More recently, nuclear physicists have developed methods and techniques for producing
neutron-rich, short-lived isotopes of a number of nuclei: reported
isotopes include a helium isotope with up to 8 neutrons – 6 more than the 2 neutrons in the stable variety, carbon isotope with up to 16
neutrons (13 more than the stable variety) and so on. A number of
isotopes have been produced for different elements and their radius measured. In some cases it was found that the radius of one unstable
isotope was unusually large: the additional neutrons were too distant
from the stable core. These were called halo nuclei. I will discuss the
use of this metaphor, transferred from poetry, religion, and astronomy
to nuclear physics.
-
Metaphors in the Languages of Science 17
The study of unstable isotopes helps nuclear physicists to study
nuclei at the ‘edge of stability’ and to infer something about nuclear
forces. We already have two spatial metaphors: first, the idealized
(one-dimensional) line standing in for the concept of a directly proportional relationship between the number of neutrons and protons;
direct proportionality is plotted as a graph and the graph is a straight
line.. And, second, the metaphor of a (two-dimensional) edge. The line of ‘stability’ is an idealization: for Helium 6, the two extra-
neutrons are distant enough not be subjected to nuclear forces within
the otherwise stable core of the Helium nucleus (2 protons and 2
neutrons) but they still are sufficiently attached to the core to form a
‘nucleus’. The extra neutrons appear to ‘drip’ out of the Helium-6
nucleus, thus forming a halo – a kind of neutron ‘dust’ around the
stable core, much like the dust particles that surround our Moon and, under certain conditions, give the semblance of a halo.
Let us now look at some evidence of the incorporation of the
various metaphors associated with the so-called halo nuclei, which are neutrons dripping towards the dripline. A further specialisation of this
sub-branch of nuclear physics illustrates how a metaphor has been
borrowed even from heraldry – namely from an inscription in the seal of the Princes of Borromeo (a 15th century kingdom in what is now
Italy). The evidence is from a 1.32 million words corpus created from
279 documents – journal articles, books, theses, conference
announcements – written by nuclear physicists between 1970 and
2005 – a kind of post-modern nuclear physics corpus.
The dripline (also written drip line) acts as a line in space: so things may happen at, above, along, below, near, or far from the
metaphorical line. Below is a concordance of the use of spatial
colligates of the dripline drawn from our corpus of post-modern nuclear physics. This includes nuclear pairing correlations,
wavefunctions, exotic nuclei, and nuclear halos at the dripline. As if
to reassert the metaphor, it also talks of nuclei ‘well past the literal dripline’.
-
Khurshid Ahmad 18
nuclear pairing
correlations
at the dripline
particle decay modes at the dripline
single particle states and
wavefunctions
at the dripline
structure in light nuclei at the neutron dripline has given new
impetus
stability and exotic nuclei at the neutron dripline
nuclear halos are
expected
along
the
drip-
lines
where nucleon
single-particle
can be pursued to
measure
the
entire
dripline for heavy nuclei
within a few nucleons of where
the
dripline is presently
anticipated
The dripline is also used in the abstract, with references to the study, investigation and access to nuclei:
studying nuclei along the proton dripline
preliminary investigations of
nuclei
at the dripline
offer access to nuclei right at the dripline
The term halo is also used in a descriptive sense, as in: a halo of diffuse neutron
neutron halo of 11Li(thium) nucleus
or halo of valence particles
the halo of Li(thium)
Typical for specialist writing, halo appears as an adjectival-noun, as in
different kinds of halo nuclei and with reference to the properties of a
halo nucleus – as for density distribution within a halo nucleus:
known halo nucleus 6He(lium)
neutron halo nucleus 15C(arbon)
neutron halo nucleus 11Be(rrylium)
neutron halo nucleus 6He(lium)
proton halo nucleus 8B(oron)
halo nucleus elastic scattering
halo nucleus density distributions
two-neutron halo nucleus
-
Metaphors in the Languages of Science 19
However, there are many more examples of the use of the term as a
component of a compound:
halo bound state halo orbit
neutron halo breakup
reactions
halo orbitals
neutron halo candidate halo particle
wavefunction
halo characteristic halo particle mass
halo charge halo phenomena
halo clusterization halo physics
halo configuration halo picture
halo constituents halo projectile
borromean halo continuum halo properties
halo core halo proton
the halo degrees of
freedom
halo radii
the halo densities proton halo reactions
transverse halo density halo region
neutron halo distribution halo sizes
the halo distribution resonance halo sources
borromean halo excitation
structure
halo spectrum
low halo excitation
energies
halo state
halo excitation
functions
proton halo structure
halo excitation
spectrum
pronounced halo system
halo fragments and
target
halo type of
systems
halo model halo wave functions
One of the contemporary terms used instead of halo was skin. The
extra neutrons in neutron-rich nuclei act like a skin around the stable core:
-
Khurshid Ahmad 20
a significant neutron skin appears
best examples of neutron skin behaviour
whether [..] a neutron skin does exist with a
have neutron halo or skin structures
possibility of halo and skin systems in heavier nuclei
the rapidly increasing neutron skin thickness as a function of a
for the 6He(lium) neutron skin thickness was about
The term skin is used far less frequently now than in the early days of
artificially created neutron-rich nuclei: halo is used about 12 times
more often than skin – the plural halos is used 10 times more often
than skins. If we compare the use of the two terms in our specialist
corpus and in the British National Corpus, it turns out that there is a
pronounced and noticeable propensity for using the term halo – which
is 596 times more frequent in the specialist corpus than in the BNC,
calculated by comparing the relative frequency of the term in the
specialist corpus and in the BNC; the plural is used 765 times more often. The term skin is used with about the same relative frequency in
both corpora (Table 2).
Term f f/N Weirdness Term f f/N Weirdness
halo 1284 0.097% 596 skin 101 0.008% 0.95
halos 81 0.006% 765 skins 8 0.001% 1.1
Table 2. A contrastive distribution of keywords in our nuclear physics corpus (N=1.32 Million tokens; 279 documents, published between 1970-2005,
mainly American English).
Discussion of halo nuclei includes a reference to a coat of arms: a
transfer of meaning from heraldry into nuclear physics. The neutron-
rich Helium isotope that has a skin or halo of 2 extra neutrons presents
a special problem for physicists, as the system He-
4+neutron1+neutron2 appears to be much longer lived than any of its binary constituents: He-4+neutron, and di-neutron (neutron1+
neutron2). It was suggested that there are three sub-systems in Helium-
6: He-4+neutron1, He-4+neutron2, and the di-neutron. These can be
-
Metaphors in the Languages of Science 21
visualized as forming three intersecting rings but if one ring is taken
out all three fall apart. For this reason they are usually known as
Borromean Rings, after the heraldic symbol used by the Princes of
Borromeo, in northern Italy:
‘Borromean’ is also used as an adjective to describe a different type of halo nuclei. The full term borromean halo nucleus/nuclei is used to
describe its creation, properties, and break-up as shown in the
concordances below:
excitations of 2-neutron borromean halo nuclei
continuum spatial correlations in borromean halo nuclei
correlations in borromean halo nuclei
breakup of borromean halo nuclei diffractive breakup of borromean halo nuclei
relativistic fragmentation of borromean halo nuclei
ground state properties of borromean halo nuclei as 6He, 11Li
series of borromean halo nuclei such as 11Li ,
explorations of spectra of borromean halo nuclei
continuum spectra of the borromean halo nuclei
And, sometimes the ‘halo’ is ellipsed in the compound:
bound hyper-radial wavefunctions for borromean nuclei
continuum spectra for borromean nuclei Halo phenomena in light borromean nuclei
nuclear reactions of borromean nuclei bound states of borromean nuclei
internal structure of borromean nuclei neutron-rich double borromean 8He nucleus
-
Khurshid Ahmad 22
4. Afterword and thanks to Goodman
I would like to end with Nelson Goodman’s observation about the
creativity in the use of language shown by scientists:
The artist’s resources – modes of reference, literal and non-literal, linguistic
and non-linguistic, denotational and non-denotational, in many media – seem
more varied and impressive than the scientist’s. But to suppose that science is
flatfootedly linguistic, literal, and denotational would be to overlook, for
instance, the analog instrument often used, the metaphor used, the metaphor
involved in measurement when a numerical scheme is applied in a new realm,
and the talk in current physics and astronomy of charm and strangeness and
black holes. Even if the ultimate product of science, unlike that of art, is a
literal, verbal or mathematical, denotational theory, science and art proceed in
much the same way with their searching and building. (Goodman 1978: 106-7)
It is the use of metaphor that underpins creativity both in the arts and
the sciences. The study of metaphor can enrich work in LSP.
Particularly in the study of terminology, sometimes due to its commitment to clarity in human communication and sometimes due to
one-to-one correspondence between a term and a concept, LSP may
appear ‘flatfootedly linguistic, literal, and denotational’. However, the
emphasis in terminology on organising concepts with a degree of
clarity and consistency, may stem from a rightful distrust of non-
literal reference. Metaphor can be regarded as the study of how one
human or a group of human beings relate their often unusual insights
and speculations of what there is through the agency of language. In
the limited evidence presented in this chapter, we might be led to believe that language invariably involves the use of linguistic
metaphors in the writings of scientists, but language is partly innately
endowed and in part influenced by the culture and environment of its speakers. It is the cultural and environmental influences that may
motivate the use of metaphors, and not surprisingly metaphors take on
their own scientific or specialist life becoming the centre-piece of
scientific writing. Terminology and metaphor appear intertwined at
least at the beginning of a science; subsequently, perhaps, when the
metaphor dies, scientists have fun and indulge in parody.
-
Metaphors in the Languages of Science 23
References
Ahmad, Khurshid 1997. Deconstructing Knowledge and Scientific Writing: Acquisition and Representation of Knowledge. In
Lundquist, Lita / Picht, Heribert / Qvistgaard, Jacques (eds)
Proceedings of the 11th European Symposium on Language for
Special Purposes. Copenhagen, Denmark, 18-22 August 1997.
Copenhagen: Copenhagen Business School, 25-53.
de Beaugrande, Robert A. 1996. LSP and Terminology in a New
Science of Text and Discourse. In Galinski, Christian / Schmitz,
Klaus-Dirk (eds) Proceedings of TKE (Terminology and
Knowledge Engineering) 1996. Frankfurt: Indeks Verlag, 12-34. Chew, Matthew K. / Laubichler, Manfred D. 2003. Perceptions of
Science: Natural Enemies – Metaphor or Misconception?.
Science 301/5629, 52-3. Feyerabend, Paul 1993. Against Method. London: Verso.
Friztsch, Harald 1983. Quarks: The Stuff of Matter. London: Allan
Lane. Gell-Mann, Murray 1964. A Schematic Model of Baryons and
Mesons. Physics Letters 8/3, 214-5.
Gell-Mann, Murray 1994. The Quark and the Jaguar: Adventures in
the Simple and the Complex. London: Little Brown.
Gell-Mann, Murray 1997. Three Quarks for Muster Mark. Interview
transcript in Wolpert, Lewis / Richards, Alison (eds) Passionate
Minds: The Inner World of Scientists. Oxford: Oxford University Press, 159-65.
Goodman, Nelson 1978. Ways of Worldmaking. Indianapolis: Hackett.
Hoffman Robert R. 1985. Some Implications of Metaphor for
Philosophy and Psychology of Science. In Paprotté, Wolf /
Dirven, René (eds) The Ubiquity of Metaphor. Metaphor in
Language and Thought. Amsterdam: Benjamins, 327-80.
Holton, Gerald 1973. Thematic Origins of Scientific Thought: Kepler
to Einstein. Cambridge (Mass.): Harvard University Press.
-
Khurshid Ahmad 24
Jeans, James 1950. The Growth of Physical Sciences. London:
Readers Union / Cambridge: Cambridge University Press.
Kövecses, Zoltán 2002. Metaphor: A Practical Introduction. Oxford:
Oxford University Press. Lakoff, George 1987. Women, Fire And Dangerous Things: What
Categories Reveal About The Mind. Chicago: University of
Chicago Press. Lawrence Berkley Labs 2006. Scale of the Atom? http://
particleadventure.org/particleadventure/frameless/scale.html.
Mayr, Ernst 2004. What Makes Biology Unique: Considerations on
the Autonomy of a Scientific Discipline. Cambridge: Cambridge
University Press.
Prabhavananda, Swami / Isherwood, Christopher 1953. The Song of
God - Bhagvad Gita. London: Phoenix House. Salam, Abdus 1990. Unification of Fundamental Forces: The First of
1988 Dirac Memorial Lectures. Lecture notes compiled by
Johnathan Evans and Gerard Watts. Cambridge: Cambridge University Press.
Shanker, Stuart. G. 1987. The Decline and Fall of The Mechanist
Metaphor. In Born, Rainer (ed.) Artificial Intelligence: The Case Against. London: Croom Helm, 72-131.
Stamos, David M. 2003. The Species Problem: Biological Species,
Ontology, and the Metaphysics of Biology. Oxford: Lexington
Books.
Turing, Alan M. [1950] 1990. Computing Machinery and Intelligence.
In Boden, Margaret (ed.) The Philosophy of Artificial Intelligence. Oxford: Oxford University Press, 40-66.
Verschuuren, Gerard M.N. 1986. Investigating the Life Sciences: An
Introduction to the Philosophy of Science. Oxford: Pergamon Press.