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I
ndia has more than a century old tradition of
creating and contributing to physics at the
highest level, with a very wide base today of
institutions, skills, knowledge and research
activity. In this brief overview, we try to convey asense of this experience. We then set the stage by
recalling the unique pre-Independence (1947)
contributions to physics. Some of the highlights of
physics research in India in the following half century
are then mentioned, in two parts; the period till
roughly about a decade ago, and the last ten years.
The emphasis of India's comprehensive
intellectual culture was broadly linguistic,
philosophical and literary. However, thinking about
the physical world, inventing mathematical ideasand languages, and experimentation and technology,
all have ancient roots. One example of each of the
above may be mentioned because, consciously or
not, this is one of the formative influences of
contemporary Indian activity in physics. The atomic
theory was hypothesized by Kanada (6th century
BC) who, along with Prasastapada, was the founder
of the philosophical school called Nyaya Vaiseshika
or Logical Atomism. Their argument for the
particulate nature of matter was the manifest
inequality of different bits of it; if matter were
infinitely divisible, how could a mustard seed be
unequal to the Meru Mountain ? The philosophers
of this school went on to describe diatomic and
triatomic molecules formed of elementary atoms,
thermal dissociation of molecules, and shape and
size of atoms. The Kerala School of mathematicians,
starting with Madhava in the 14th century,
discovered and used differential and integral
calculus in the course of expressing trignometric
functions as an infinite power series, obtaining the
famous series of Gregory, Newton and Leibniz and
thence a value of accurate to 11 decimals, all thistwo to three centuries before calculus was invented
in the West, in a different context, by Newton and
Leibniz. The fertile coming together of these three
kinds of activity, a hallmark of contemporary science,
did not happen and it was with the British conquest
of India that science as we know it today entered the
country. Western higher education began to be
officially sponsored and supported from the early
19th century. Towards the end of the 19th century
and the beginning of the 20th, three factors, namelythe results of this policy, resurgent national as well
as cultural consciousness, and the revolution in
physics came together to create the most remarkable
period in modern Indian science. The best known
figures of this period are icons in the contemporary
national imagination; together they gave India a
special position in the physics world. Their work
and influence are briefly mentioned here, both for
their own interest and because this is the immediate
background for physics in India.
The first, and in many ways the most unusual
was Jagadis Chandra Bose (1858-1937), a pioneer in
experimental studies of ultra-short (millimetre
wavelength) electromagnetic waves, and in the
physical response of plants to stimuli. He went to
study medicine in London in 1880, shifted to science
at Cambridge and returned to teach at Presidency
College, Kolkata. Here, in the 1890's he started
PHYSICS
C H A P T E R I X
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experiments on microwaves, generating and
detecting them over distances of the order of a mile,
a year or more before Marconi's experiments on
longer wavelength radio waves. He established
their identity as transverse electromagnetic waves
with ingenious but materially simple table top
experiments, taking advantage of their millimetre
wavelength. The horn antennae, waveguides, and
the semiconductor rectifiers he developed for
detection prefigured the detailed exploration of
microwaves and the knowing use of pn junction
(silicon) rectifiers by half a century. In
the early years of the 20th century, J.C.
Bose began studying electrical and
mechanical response of plants to stress,
by devising techniques for amplifying
extremely minute movements andchanges. Clearly it was far too early to
make scientific sense of the striking
results, and their often anthropomorphic
description in a literal minded scientific
age did not help. This scientific explorer
was also a great teacher, emphasizing
demonstration and experiment.
Somewhat later came C. V. Raman
(1888-1970), the greatest of Indianscientists. Precocious (his first scientific
paper was published when he was
about seventeen), indigenous and
entirely self taught, he was the natural
scientist of the world of light and sound
waves. The first half of his career (1907-
1933) was spent in Kolkata and the
remainder in Bangalore. He is best
known for his discovery (Raman effect,
1928) that photons interacting withmatter can change their frequency, the
shift being characteristic of its internal
excitations. Prior to this, photons were known to be
fully absorbed (e.g. photoelectric effect) or scattered
elastically (ordinary or Raleigh scattering of light,
or Compton effect); these are first order processes.
The Raman effect, second order in the photon field,
is a new phenomenon probing the internal states of
molecules and of condensed matter. Some of the
other major discoveries of Raman are the origin of
the musical nature of the drums tabla and
mridangam, diffraction of light from stationary
wavefronts created by ultrasound in liquids, light
scattering from polymers and from short-lived shear
fluctuations in fluids, and the soft mode associated
with structural phase transitions in solids. Raman's
style was imaginative and incisive, doing relatively
simple but often ingenious experiments to probe
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A typical flower texture exhibited by a columnar
liquid crystal. This mesophase was discovered in
compounds made of disc-shaped molecules in the
Raman Research Institute in 1977.
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phenomena. He was primarily a research scientist
with a large number of research students over a long
(~ 40 years long) and productive scientific career;
these students helped shape physics in India for a
generation or more.
Satyendranath Bose (1894-1974) was the firstto realize the statistical mechanical consequences of
identity in quantum particles (Bose-Einstein
statistics) and applied it to light or photons, thus
inventing quantum statistical mechanics. Meghnad
Saha (1893-1956) showed that the origin of unusual
stellar line spectra is the presence of different ionic
species in stellar matter due to thermal removal of
different numbers of electrons from radiating atoms,
thus clarifying a great mystery in astrophysics andproviding a way of estimating temperatures of stars.
Saha was also active in public life, e.g., science and
economic planning, calendar reform, a stint as
nominated Member of Parliament, and founding
and nurturing an Institute of Nuclear Physics in
Kolkata. K.S.Krishnan (1898-1961) collaborated in
the discovery of the Raman effect, did very precise
measurements of magnetic anisotropy in crystals
and understood the results in terms of crystal fields,
and also proposed a theory for the resistivity ofliquid metals based on the scattering of free
electrons by a dense highly correlated collection of
atoms. The theoretical astrophysicist S.
Chandrasekhar (1910-1995; Nobel Prize, 1963)
started his epic career from India where he had
begun to think at the age of twenty or so about the
maximum mass a stable star can have, the
Chandrasekhar limit; he went on to develop this
and other areas of astrophysics and cosmology on
a monumental basis in England and then USA
where he settled. These physicists worked mostly
at universities, those being the only places for higher
education and research in the pre-Independence
period except for two primarily research
institutions, namely the Indian Association for the
Cultivation of Science, Kolkata, and the Indian
Institute of Science, Bangalore.
In the 1950s, the picture changed in several
ways. The charismatic Prime Minister of inde-
pendent India, Jawaharlal Nehru, believed
strongly in nation building through centralized
planning and government institutions, and in the
essentiality of science both basic and applied for
this. As a result, a large number of state supportedresearch and development laboratories were set
up, for example the cluster associated with the
Council of Scientific and Industrial Research. This
was also the period when big science physics
began to become prominent all over the world
following the release of nuclear energy, and the
atom bomb. The field found a visionary leader in
Homi Bhabha, (1909-1966) an outstanding
theoretical physicist who was also very close toNehru, well known for his work on 'showers' of
electrons and positrons accompanying high
energy cosmic rays as they pass through the
atmosphere. Bhabha conceived and helped set up
a collection of institutions such as the Tata
Institute of Fundamental Research (TIFR, 1945)
and the DAE (incorporated as Atomic Energy
Commission in 1948) which itself had a wide
spectrum of activities ranging from power
reactors to metallurgy of nuclear fuel materials.He inculcated the spirit of self-sufficiency in
instrumentation and technology development.
He also built up people and groups, by choosing
well, giving them the freedom and support
needed, and generating and sustaining a spirit of
great things to be done.
In physics, a number of groups quickly attained
international prominence (in the 1950s and early
1960s) in relatively new fields, e.g., cosmic ray
research, neutron scattering and radio astronomy. In
the field of cosmic rays, D.M. Bose and others from
Kolkata had observed very early (in 1941) cosmic ray
particle tracks in photographic plates exposed in the
Himalaya, and had identified new particles with a
mean mass 200 times that of the electron. This was
six years before Powells systematic development of
the photographic emulsion method, and discovery
of pi mesons in cosmic rays. In TIFR, the cosmic ray
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group used balloon flights carrying nuclear emulsion
stacks to obtain important results on masses and
decay modes of heavy unstable particles (produced
by cosmic rays). This group established itself overthe years as a major group in the study of primary
cosmic radiation, particularly the heavy primary and
high energy electron components. The extensive air
shower array at Ooty was one of the leading facilities
for the exploration of extremely high energy cosmic
rays. The various depths available in the Kolar Gold
Fields (KGF), up to almost 2 miles below the surface
offered one of the few world class places for the study
of extremely energetic cosmic ray mu mesons and
neutrinos. Experiments at KGF were carried out on
an international basis with groups from England and
Japan; the collaborative effort with the Japanese
group lasting over three decades must surely be one
of the longest collaborative scientific efforts in the
world. The KGF work resulted in the most
comprehensive depth-intensity data for muons up
to the greatest depth of 9,600 ft. below the ground.
The first natural (atmospheric) neutrino interactions
were detected in KGF in 1965. The first dedicated
experiment to search for nucleon decay to a life time
of up to 1,031 years was carried out at KGF; this was
the first such detector operational in the 100 ton
category. In neutron scattering, the group at BARC
was one of the early leaders (in the 1960s) in using
inelastic scattering to probe elementary excitationsin condensed matter. The occultation radio telescope
at Ooty, set up in 1970, provided important results
relating to the apparent angular size of galaxies with
their energy flux. The development of optical
telescope facilities also dates to this period; a number
of interesting results such as the discovery of rings
surrounding Uranus, and the measurement of star
clusters in the Large Magellanic Cloud and their
kinematics are from this period.
Somewhat later, a number of small or
laboratory-scale activities, mainly in condensed
matter physics, centered around individuals, began
to bear fruit. Perhaps the best known is the sustained
work on liquid crystals done at Raman Research
Institute in Bangalore; the discovery of a new
arrangement in liquid crystals, the discotic phase with
a stacking of disc like molecules, (in 1978) is perhaps
a high point in the contributions by this group, which
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Balloon flights for study of cosmic rays.
(Inset): Bhabha releasing a balloon.
Photos:M.G.K
.Menon
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continues to be one of the leaders in the world in this
field rich in new science and technology. A group in
TIFR has, for more than a generation, made often
pioneering discoveries in the still lively and
fascinating field of rare earth intermetallic
compounds. Their forte is synthesis and experimentalanalysis of anomalous systems in which the generally
completely atomic f electrons (of the rare earth
elements) hybridize with the s andpband electrons, to
produce heavy electron metals and insulators (the
nearly localized electron moves slowly from site to
site), or give rise to novel superconductors with
unlikely ingredients (the rare earth borocarbides). In
the field of quasicrystals, significant early
contributions on different families, on structure, andon systematics of approximants are due largely to the
Indian community of physical metallurgists. This was
in a sense an offshoot of a major programme on
rapidly quenched metals. Interesting studies on
critical phenomena, e.g. breakdown of the rectilinear
diameter law near Tc, and precise measurements of
unusual exponents and critical light scattering near
special critical points in carefully chosen fluid
mixtures, date from this period, and are continuing.
Following the Raman tradition, a number of softmodes in ferroelectrics were studied by optical as well
as neutron scattering methods. High pressure studies
of phases and phase transitions in metals and alloys
have yielded insight into electron phases.
The tradition of atmospheric studies goes to
back to S.K. Mitra at Kolkata in the thirties, and
continued with important work on low frequency
propagation in the ionosphere, aeronomy and the
ozone problem.
We now describe Indian contributions to
theoretical physics from the 1950s till the 1980s. In
the 1950s a programme of selecting and training
physicists, chemists and engineers was started in
Mumbai under the leadership of Bhabha. This
provided the growing atomic energy programmme
with professionals; many research physicists also
started their career here. In addition, many scientists
who did their Ph.D. and subsequent research
abroad returned to India. A number of centres of
quality (universities and research institutes) had
been training professional physicists since the
twenties or so. Because of increased mobility and
ease of communication, international collaboration
as well as working abroad for some time becamecommon. All this, along with a rapid growth in the
number of physics based government supported
institutions after Independence, led to a major
expansion in physics; because of the relative
sparseness of experimental research and the slant
of the intellectual culture, there was (and is) a large
thrust in theoretical physics. We mention below
some contributions in areas such as particle and
nuclear physics, gravitation and cosmology,condensed matter physics and statistical mechanics.
Theoretical particle physics has over the past
half century gone through many stages. To all of
these, Indian physicists have made significant
contributions. Perhaps the best known departure
was the hypothesis in the late fifties (1957) that the
parity violating weak interaction and decay process
is maximally so, arising phenomenologically out of
a fermion current that is of the form (V-A), where V
is a vector and A an axial vector. This (V-A)hypothesis, proposed after analyzing all available
experiments (and inconsistent with a few of them,
which were subsequently shown to be in error), was
a breakthrough towards the present theory of
electro-weak interactions. An early area of
important activity was the formulation of
constraints and sum rules on various elementary
processes, using only general principles in the
absence of a dynamical theory, with important
results on scattering cross sections and amplitudes.
In the phase where algebraic properties of quantum
particle currents were analyzed, exact low energy
theorems were obtained. Gauge field theory,
quantum chromodynamics (QCD) and electro-weak
unification leading to the standard model of
fundamental particle interactions, have all seen
important original contributions, ranging from
results in relevant quantum field theories to
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predictions and analyses of experiments. For
example, it was shown quite early that the quanta
of a massless Yang-Mills (gauge) field are confined
(much before the advent of QCD). Very early, one
loop (higher order) corrections to muon decay were
obtained in gauge theory and shown to be finite. Alepton isolation criterion for the top quark was
proposed as a means of detection, and prediction of
its mass was made. Charged quantum solutions and
charged vortex solutions were shown to be present
in appropriate field theories. Various possible
experimental signatures for detecting the quark
gluon plasma in high energy collisions between
heavy ions have been analyzed, and their
uniqueness discussed. The consequences of the spincontent of nucleons in several nuclear reactions
were examined within the QCD. The detailed nature
and implications of the chiral phase transition in
lattice QCD were determined. Physics beyond the
standard model, namely in supersymmetric models
has been actively explored, both from a formal
viewpoint (e.g. the solution to the naturalness or
gauge hierarchy problem in supersymmetric field
theories, this being a strong theoretical argument
for such theories) and the approach of using highenergy collision events to set limits on say masses
of supersymmetric analogues of quarks, gluons, and
Higgs bosons. Another fruitful area is at the active
interface of cosmology and particle physics ; an
early example is a limit on masses of weakly
interacting particles such as neutrinos, from
cosmological considerations (this was perhaps the
first suggestion of the existence and relevance of
dark matter in the universe).
In theoretical nuclear physics, a great deal of
original work has been done on the microscopic
approach to nuclear structure, especially the shell
model. For example, relating the spectrum of a
particle - particle and a particle - hole configuration,
the magnetic moments of neighbouring nuclei could
be connected, and an estimate obtained for three
body nuclear forces. A method for reducing the
nuclear three body problem to two body problems
for separable potentials was used extensively for
understanding few nucleon systems, and also for
the three quark model for a nucleon. Some of the
conclusions from the latter presage a new degree of
freedom for quarks, now well known as 'colour'.
There is a long tradition of research in generaltheory of relativity and gravitation, earlier mainly
in departments of mathematics. Some of the early
major results are the exact solution of Einstein's
equations for the case of any electrostatic field, and
for a radiating star, as well as the equation which
turned out to be the key ingredient in the proof of
the black hole singularity theorems (Hawking and
Penrose). Other important contributions were made
to gravitation theory and cosmology, such as thedevelopment of steady state cosmology, various
aspects of black hole physics, and the seismology
of the sun based on its normal modes of oscillation.
In the area of condensed matter physics and
statistical mechanics, activity started in the 1960s.
An early result was the recognition that orbital
ordering in Jahn Teller distorted oxides is an order
- disorder transition, rather than displacive. It was
shown that the exact ground state of an
antiferromagnetically coupled spin system (for aparticular ratio between nearest and next nearest
neighbour couplings) is a dimerized superposition
of spin singlets, an important signpost in quantum
magnetism and a forerunner of spin singlet or
resonating valence bond ideas for
antiferromagnetism and high temperature super-
conductivity. A theory of unusual time dependent
specific heat and heat pulse propagation in glassy
dielectrics at low temperatures was developed.
Qualitative and quantitative consequences of
quantum spin fluctuation effects in itinerant electron
(fermion) systems with ferromagnetic transition
temperature T ~ 0 were spelt out ; the related,
presently active field of quantum critical
phenomena developed a generation later. The
theory of liquid to solid transition in (real) dense
classical systems was developed, in terms of a new
free energy functional of the density involving
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known strongly nonlocal fluid phase correlations.
This approach has proved of value in a number of
phenomena in which both the fluid and the solid,
as well as large deformations of the solid are
involved.
Optical nonlinear susceptibilities for semi-conductors and at metal surfaces were predicted
and calculated, as was also the prominent surface
enhanced Raman scattering. The nature of ground
state and excitations in coupled spin chains is a
theme of continued activity. It is a field that has
recently seen a very large amount of experimental
work because of synthesized spin ladder
compounds with unusual properties. Here, exact
solutions for ground states for chains, ladders andspecial two dimensional systems have been
obtained. Multimagnon bound states and solitonic
excitations have been explored. Conservation laws
for and exact integrability of one dimensional lattice
electron systems with interaction have been
discovered. A complete renormalization group
based analysis of the properties of a magnetic
impurity in a metal (Anderson model) as it evolves
from weak to strong coupling with its environment
on cooling was developed. An inverse orbitaldegeneracy expansion was proposed for Anderson
model magnetic impurity systems, in the context of
mixed valence and heavy fermions. The essentiality
of 'hedgehog ' like spin defect textures for the
ferromagnetic - paramagnetic transition in systems
was shown. The long time relaxation behaviour of
disordered ferromagnets was shown to be
dominated by exponentially improbable
ferromagnetic domains. The dependence of the area
of the hysterisis loop in magnets on the size
frequency of the reversing field was analyzed for
the first time and power law relations obtained, the
results being close to those known from the
experiments of Steinmetz more than a century ago.
The above account necessarily touches on a wide
range of phenomena and models, reflecting the
nature of condensed matter physics.
In other areas of theoretical physics, some of
the major contributions are the following. In the
1950s, Pancharatnam, while exploring the
description of the state of polarized light in terms
of a vector with the tip on the surface of a 'Poincare'
sphere, clearly understood and enunciated the idea
of a geometrical phase (Berry phase; now oftencalled the Berry-Pancharatnam phase) associated
with changes of polarizarion described by the tip
executing a closed curve on the Poincare sphere.
Subsequent work includes extension to non-closed
curves, kinematics and mathematical structure of
the theory. In a contribution of central value to
biochemistry and biophysics, Ramachandran and
colleagues showed that dihedral angles between
successive molecular groups in proteins aresterically constrained, and can lie only within
certain regions of values (Ramachandran diagram).
In the area of quantum optics, in addition to the
basic coherent state representation of electro-
magnetic fields, pioneering work has been done in
areas such as cooperative resonance fluorescence,
pair coherent states and squeezing etc.. Plasma
physics is another area with significant Indian
contributions, e.g. the theory of parametric
instabilities and stabilization of tokamakballooning modes.
The survey is concluded by mentioning some
physics research facilities and achievements pertaining
to the last decade or so. The attempted description will
be grossly incomplete and patchy, since the physics
community is rather large, with perhaps 5,000 or more
Ph.D. physicists. Most major areas of physics are
pursued, so that there is a large and widespread
knowledge and research base. This base is formed by
the sustained efforts of a large number of dedicated
practitioners working under difficult conditions, and
a relatively small number of prominent figures or
leaders, some of whom have made contributions of
major significance to physics. Afew individuals have
successfully built and/or nurtured major institutions
and facilities, especially in government departments
connected with atomic energy, space, defence etc. A
culture of self-reliance of developing the tools needed,
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and of applied science at a high level of competence
in diverse areas, has been developed. In experimental
physics research, a few fields stand out in terms of the
investments made, and facilities created. These are
overwhelmingly in the area of 'big' science. In the field
of astronomy and astrophysics (as described in theChapter on this area) a number of major facilities have
been set up that are of world class and available widely
to scientists within India as well as from abroad. A
number of medium energy particle accelerators have
been functioning in the country, e.g. a heavy ion
accelerator in the Nuclear Science Centre, Delhi, used
as a common facility in Nuclear Physics and Materials
Science for all Indian universities for about a decade.
A major tokamak facility using a solid statesuperconducting magnet is coming up at the Institute
of Plasma Research, Ahmedabad. An ultraviolet
synchrotron is operational at the Centre for Advanced
Technology, Indore, and an X-ray synchrotron is
expected to come on line soon.
There have been many interesting
developments in experimental condensed
matter/materials physics. The energy dependence
of the electronic excitation spectrum near the T=0
metal insulator transition, with the possibledevelopment of a pseudogap, has been explored.
While subsequent to the discovery of
superconductivity in the cuprates, considerable
amount of materials related work was done, the
absence of quality single crystal growth and
cryogenic facilities has proved a serious handicap in
this as well as other areas. However, novel
phenomena associated with flux lattice melting,
plastic flow of the flux lattice etc. have been
discovered (TIFR) using cuprate and other
superconductor crystals grown elsewhere. The
nature of atom (or molecule) light interaction in
intense laser fields has been actively probed. Aspects
of electronic and optical processes in quantum well
semiconductor structures have been studied by
several groups. An interesting new development in
a field of basic interest as well as current activity is
the detection and quantitative analysis of electrical
noise near the metal insulator transition in silicon
(universal conductance fluctuation), its suppression
by electric fields and thermal dephasing. Very careful
structural work on quantum and mixed
ferroelectrics has greatly clarified the nature of
phases in these; the phenomena and materials are ofimportance both scientifically and technologically.
In the growing field of colossal magnetoresistance
oxides (manganites) a large amount of well known
work exploring the bewildering variety of electron
driven phases and phase transitions has been done
(mainly at IISc). Two notable features of this body of
work are the fruitful collaboration between solid
state chemists and physicists, and the systematic
study of phenomena using several probes, e.g.transport, tunnelling, heat capacity, light scattering
and EPR. Fullerenes (C60, C70....) and carbon
nanotubes are another aspect of this kind of work.
For example, in Y junctions of carbon nanotubes,
rectification has been shown to occur; many unusual
properties of single and multiwalled nanotubes are
coming to light. We have here entered the completely
quantum world of nanoscience where there are no
boundaries between different areas of science, and
between science and technology. However, facilitiesfor sustained frontier work in this area are very poor.
A growing concern in modern physical science is the
study of soft systems, such as colloids, membranes,
foams, and gels, in which the energies associated
with the relevant degrees of freedom are of low
energy (~ kB T). Here, in addition to liquid crystals
mentioned above, aggregates of colloids forming a
glassy phase have been studied structurally (and
kinetically), diffusion of photons in this medium has
been analyzed, and surfactant based self-organized
assemblies have been probed using light scattering.
In theoretical physics, the last decade has seen
a wide range of contributions. In string theory, an
area of great intellectual ferment, the Indian
presence is quite prominent. While many of the
developments over the decade had active Indian
participation, at least two stand out because of the
critical Indian contributions namely the idea of
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duality between strongly and weakly interacting
string field theory, a major breakthrough in the field
with wide implications and an absolute value for
black hole entropy from a quantum model for it.
Contributions to theoretical astrophysics range
from an analysis of shock wave induced triggeringof starburst collections in interacting galaxies and
a calculation of the selfconsistent (gravitational)
potential at the core of elliptical galaxies to early
discussions of gravitational lensing as well as
nonlinear mechanisms for large scale structure
formation in the early universe.
Indian theorists have contributed notably to
ideas connected with high temperature super-
conductivity, e.g. the resonating valence bond modelfor antiferromagnetically coupled electron spins on
a lattice and the associated gauge degree of freedom
which are believed by many to be crucial ingredients
in any theory. A long range one dimensional
antiferromagnetic interaction model with exactly
known ground state, and with spinons was
discovered a little more than a decade ago. The
nature of interlayer tunnelling and consequences for
the puzzling anisotropy of resistivity in the cuprates
has been discussed. Avery interesting proposal fora mirrorless laser in a disordered one-dimensional
medium using (Anderson) localization properties
has been made. Anumber of interesting contributions
to mesoscopic physics, e.g. conductance fluctuations
and persistent currents in mesoscopic structures,
have been made. In the area of strongly correlated
electron systems, the dynamical mean field theory
has been extended in several significant ways, in
particular going beyond the single site
approximation to describe clusters. In what has now
become a standard method in the field, it has been
shown how photoemission data can be used to
derive reliable and precise information about electron
spectral density in cuprate superconductors.
In statistical mechanics, a unique exactly
soluble model for self-organized criticality, the
Abelian sandpile model, was formulated and the
results analyzed. A number of interesting soluble
models in low dimensions for interfacial dynamics
were proposed and solved in the broad area of
nonequilibrium statistical mechanics. Multiscaling
behaviour in turbulence has been numerically
explored. Chaotic control of cardiac arrhythmia is
one of the many fascinating contributions toemerge from the increased attention given to
nonlinear dynamics and chaos. Some others are
chaotic computing, yielding of solids and
premonitory phenomena in earthquakes. The
nature of glassy free energy minima and their
landscape, and a formal approach to freezing in
disordered systems, are some efforts at
understanding one of the major unsolved problems
in condensed matter physics, namely the glasstransition. In the area of equilibrium statistical
mechanics, phase transitions in polymeric systems,
the nature of the DNA denaturation / unzipping
transition, and flux lattice melting are some of the
notable efforts. Original work on autocatalytic
networks as involved in prebiotic evolution has
been carried out. Work on spin ice, namely dipolar
interacting spin models with residual entropy
(measured in some pyrochlores) as in some models
of ice, has attracted attention.The above incomplete survey suggests that
physics activity in India continues at a high
international level and over a widening range. While
this is broadly true, there are a number of clear signs
suggesting that immediate corrective action is
necessary for the continued vitality, growth and
usefulness of not only physics but science in general.
These signs are briefly: (a) the generally poor state of
experimental science (at least physical science) in India,
due to continued lack of support for laboratory-scale
physical science (by a factor of five or more), (b)
relative paucity of physics related (high) technology,
(c) the concentration of research in a small number of
non-teaching institutions with few students, and the
blighting of universities with many students, an
inherently unstable arrangement not found in
scientifically vigorous societies, and (d) a sharp decline
in the number of students taking up physics.
120 P U R S U I T A N D P R O M O T I O N O F S C I E N C E