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Image:Meissner_Crop.jpg Superconductivity thumb|150px|right|A [[Superconductivity|Superconductor demonstrating the
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'''Physics''' (from the
Greek language Greek, φυσικός (''physikos''), "natural", and φÏ?σις (''physis''), "nature") is the
science of the
Nature natural world, which deals with the fundamental constituents of the
universe, the
fundamental interaction forces they exert on one another, and the results of these forces. Sometimes, in modern physics, a more sophisticated approach is taken that incorporates elements of the three areas listed above; it relates to the laws of
Symmetry in physics symmetry and
Conservation law conservation, such as those pertaining to
energy,
momentum,
charge, and
parity (physics) parity. [http://encarta.msn.com/encyclopedia_761553206/Physics.html]
Physicists study a wide range of physical phenomena spanning all
length scales: from the
subatomic particles of which all ordinary (i.e.,
baryon baryonic)
matter is made (
particle physics) to the behavior of the material
Universe as a whole (
Physical cosmology cosmology).
Physics discoveries find applications throughout the other
natural sciences as it studies the basic constituents of the natural world. Some of the phenomena studied in physics, such as the
conservation of energy, are common to ''all'' material systems. These are often referred to as
law of physics laws of physics. Others, such as
superconductivity, stem from these laws, but are not laws themselves, because they only appear in some systems. Physics is sometimes said to be the "fundamental science", because each of the other natural sciences (
biology,
chemistry,
geology, etc.) deals with particular types of material systems that obey the laws of physics. For example, chemistry is the science of
molecules and the
chemical compound chemicals that they form in the bulk. The properties of a chemical are determined by the properties of the underlying molecules, which can be described by areas of physics such as
quantum mechanics (called in this case
quantum chemistry),
thermodynamics, and
electromagnetism.
Physics is closely related to
mathematics, which provides the logical framework in which physical laws can be precisely formulated and their predictions quantified. Physical
theory theories are almost invariably expressed using mathematical relations. A key difference between physics and mathematics, aside from the difference in
Rigour rigor, is that physics is ultimately concerned with descriptions of the material world, whereas mathematics is concerned with abstract patterns that need not have any bearing on it. The distinction, however, is not always clear-cut. There is a large area of research intermediate between physics and mathematics, known as
mathematical physics, devoted to developing the mathematical structure of physical theories.
Physics attempts to describe the natural world by the application of the
scientific method.
Natural philosophy, its counterpart, is the study of the changing world by philosophy which has been also called "physics" since classical times to at least up to its separation from philosophy as a
positive science in the 19th century. Mixed questions, of which solutions can be attempted through the applications of both disciplines (e.g. the divisibility of the atom) can involve natural philosophy in physics the science and vice versa.
Overview of physics research
Central theories
While physics deals with a wide variety of systems, there are certain theories that are used by all physicists. Each of these theories is believed to be basically correct, within a certain domain of validity. For instance, the theory of
classical mechanics accurately describes the motion of objects, provided they are much larger than
atoms and moving at much less than the
speed of light. These theories continue to be areas of active research; for instance, a remarkable aspect of classical mechanics known as
chaos theory chaos was discovered in the 20th century, three cen can i get a what what turies after the original formulation of classical mechanics by
Isaac Newton (
1642—
1727). These "central theories" are important tools for research into more specialized topics, and any physicist, regardless of his or her specialization, is expected to be well-versed in them.
{| class="wikitable"
!Theory || Major subtopics || Concepts
|-
|
Classical mechanics
|
Newton's laws of motion,
Lagrangian mechanics,
Hamiltonian mechanics,
Kinematics,
Statics,
Dynamics (mechanics) Dynamics,
Chaos theory,
Acoustics,
Fluid dynamics,
Continuum mechanics
|
Density,
Dimension,
Law of universal gravitation Gravity,
Space,
Time,
Motion,
Length,
Position,
Velocity,
Acceleration,
Mass,
Momentum,
Force (physics) Force,
Energy,
Angular momentum,
Torque,
Conservation law,
Harmonic oscillator,
Wave,
Mechanical work Work,
Power (physics) Power
|-
|
Electromagnetism
|
Electrostatics,
Electrodynamics,
Electricity,
Magnetism,
Maxwell's equations,
Optics
|
Capacitance,
Electric charge,
Current (electricity) Current,
Electrical conductivity,
Electric field,
Permittivity Electric permittivity,
Electrical resistance,
Electromagnetic field,
Electromagnetic induction,
Electromagnetic radiation,
Gaussian surface,
Magnetic field,
Magnetic flux,
Magnetic monopole,
Magnetic permeability
|-
|
Thermodynamics and
Statistical mechanics
|
Heat engine,
Kinetic theory
|
Boltzmann's constant,
Conjugate variables (thermodynamics) Conjugate variables,
Enthalpy,
Entropy,
Equation of state,
Equipartition theorem,
First Law of Thermodynamics,
Free energy,
Heat,
Ideal gas law,
Internal energy,
Non-equilibrium thermodynamics Irreversible process,
Partition function (statistical mechanics) Partition function,
Pressure,
Reversible process (thermodynamics) Reversible process,
Second Law of Thermodynamics,
Spontaneous process,
State function,
Statistical ensemble (mathematical physics) Statistical ensemble,
Temperature,
Thermodynamic equilibrium,
Thermodynamic potential,
Thermodynamic processes,
Thermodynamic state,
System (thermodynamics) Thermodynamic system,
Third Law of Thermodynamics,
Viscosity,
Zeroth Law of Thermodynamics
|-
|
Quantum mechanics
|
Path integral formulation,
Scattering theory,
Schrödinger equation,
Quantum field theory,
Quantum statistical mechanics
|
Born-Oppenheimer Approximation Adiabatic approximation,
Correspondence principle,
Free particle,
Hamiltonian (quantum mechanics) Hamiltonian,
Hilbert space,
Identical particles,
Matrix Mechanics,
Planck's constant,
Operators,
Quantum Quanta,
Quantization (physics) Quantization,
Quantum entanglement,
Quantum harmonic oscillator,
Quantum number,
Quantum tunneling,
Schrödinger's cat,
Spin (physics) Spin,
Wavefunction,
Wave mechanics,
Wave-particle duality,
Zero-point energy,
Pauli Exclusion Principle,
Heisenberg Uncertainty Principle
|-
|
Theory of relativity
|
Special relativity,
General relativity,
Einstein field equations
|
Covariant Covariance,
Einstein manifold,
Equivalence principle,
Four-momentum,
Four-vector,
General principle of relativity,
Geodesic (general relativity) Geodesic motion,
Gravity,
Gravitoelectromagnetism,
Inertial frame of reference,
Invariant (physics) Invariance,
Length contraction,
Pseudo-Riemannian manifold Lorentzian manifold,
Lorentz transformation,
Metric (mathematics) Metric,
Minkowski diagram,
Minkowski space,
Principle of Relativity,
Proper length,
Proper time,
Reference frame,
Rest energy,
Rest mass,
Relativity of simultaneity,
Spacetime,
Special principle of relativity,
Speed of light,
Stress-energy tensor,
Time dilation,
Twin paradox,
World line
|}
Major fields of physics
Image:Physics_Venn_diagram.PNG thumb|Classification of physics fields by the types of effects that need to be accounted for
Contemporary research in physics is divided into several distinct fields that study different aspects of the material world.
Condensed matter physics, by most estimates the largest single field of physics, is concerned with how the properties of bulk matter, such as the ordinary
solids and
liquids we encounter in everyday life, arise from the properties and mutual interactions of the constituent
atoms. The field of
atomic, molecular, and optical physics deals with the behavior of individual atoms and molecules, and in particular the ways in which they absorb and emit
light. The field of
particle physics, also known as "high-energy physics", is concerned with the properties of submicroscopic particles much smaller than atoms, including the
elementary particles from which all other units of matter are constructed. Finally, the field of
astrophysics applies the laws of physics to explain
astronomy astronomical phenomena, ranging from the
Sun and the other objects in the
solar system to the universe as a whole.
Since the
20th century, the individual fields of physics have become increasingly
specialization specialized, and nowadays it is not uncommon for physicists to work in a single field for their entire careers. "Universalists" like
Albert Einstein (
1879—
1955) and
Lev Landau (
1908—
1968), who were comfortable working in multiple fields of physics, are now very rare.
{| class="wikitable"
!Field ||Subfields || Major theories || Concepts
|-
|
Astrophysics
|
Physical cosmology Cosmology,
Planetary science,
Plasma (physics) plasma physics
|
Big Bang,
Lambda-CDM model,
Cosmic inflation,
General relativity,
Law of universal gravitation
|
Black hole,
Cosmic background radiation,
Galaxy,
Gravity,
Gravitational radiation,
Planet,
Solar system,
Star
|-
|
Atomic, molecular, and optical physics
|
Atomic physics,
Molecular physics,
Chemical physics,
Optics,
Photonics
|
Quantum optics,
Quantum chemistry
|
Atom,
Molecule,
Diffraction,
Electromagnetic radiation,
Laser,
Polarization,
Spectral line
|-
|
Particle physics
|
Accelerator physics,
Nuclear physics,
Particle physics phenomenology
|
Standard Model,
Supersymmetry,
Grand unification theory,
M-theory
|
Fundamental force (
gravity gravitational,
electromagnetism electromagnetic,
weak interaction weak,
strong interaction strong),
Elementary particle,
Antimatter,
Spin (physics) Spin,
Spontaneous symmetry breaking,
Theory of everything,
Vacuum energy
|-
|
Condensed matter physics
|
Solid state physics,
Materials physics,
Polymer physics
|
BCS theory,
Bloch wave,
Fermi gas,
Fermi liquid,
Many-body theory
|
Phase (matter) Phases (
gas,
liquid,
solid,
Bose-Einstein condensate,
superconductivity superconductor,
superfluid),
Electrical conduction,
Magnetism,
Self-organization,
Spin (physics) Spin,
Spontaneous symmetry breaking
|}
Related fields
There are many areas of research that mix physics with other disciplines. For example, the wide-ranging field of
biophysics is devoted to the role that physical principles play in biological systems and the field of
quantum chemistry studies how the theory of quantum mechanics gives rise to the chemical behavior of atoms and molecules. Some of these fields are listed below.
Acoustics -
Astronomy -
Agrophysics -
Biophysics -
Chemical physics -
Computational physics -
Econophysics -
Electronics -
Engineering -
Geophysics -
Materials science -
Mathematical physics -
Medical physics -
Physical chemistry -
Physics of computation -
Quantum chemistry -
Quantum information science -
Vehicle dynamics
Theoretical and experimental physics
The culture of physics research differs from the other sciences in the separation of
theory and
experiment. Since the
20th century, most individual physicists have specialized in either
theoretical physics or
experimental physics. The great
Italy Italian physicist
Enrico Fermi (
1901—
1954), who made fundamental contributions to both theory and experiments in
nuclear physics, was a notable exception. In contrast, almost all the successful theorists in
biology and
chemistry have also been experimentalists. However, in the last decades,
quantum chemistry quantum and
computational chemistry became autonomous disciplines straddling the border between
theoretical chemistry and theoretical physics. Many quantum chemists or theoretical molecular physicists are therefore often considered as pure theorists.
Roughly speaking, theorists seek to develop theories that can describe and interpret existing experimental results and successfully predict future results through
Model (abstract) abstractions and
mathematical models, while experimentalists devise and perform experiments to explore new phenomena and test theoretical predictions. Although theory and experiment are developed separately, they are strongly dependent on each other. Progress in physics frequently comes about when experimentalists make a discovery that existing theories cannot account for, necessitating the formulation of new theories. Likewise, ideas arising from theory often inspire new experiments. In the absence of experiment, theoretical research can go in the wrong direction; this is one of the criticisms that has been leveled against
M-theory, a popular theory in high-energy physics for which no practical experimental test has ever been devised.
Fringe theories
*
Cold fusion
*
Dynamic theory of gravity
*
Luminiferous aether
*
Steady state theory
History
{{main|History of physics}}
{{further|
Famous physicists,
Nobel Prize in physics}}
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Since antiquity, people have tried to understand the behavior of
matter: why unsupported objects drop to the ground, why different
materials science materials have different properties, and so forth. Also a mystery was the character of the
universe, such as the form of the
Earth and the behavior of celestial objects such as the
Sun and the
Moon. Several theories were proposed, most of which were wrong. These theories were largely couched in
philosophy philosophical terms, and never verified by systematic experimental testing as is popular today. The works of
Ptolemy and
Physics (Aristotle) Aristotle however, were also found to not always match everyday observations. There were exceptions and there are
anachronisms: for example,
Indian philosophy Indian philosophers and
:Category:Indian astronomers astronomers gave many correct descriptions in
atomism and
astronomy, and the
Ancient Greece Greek thinker
Archimedes derived many correct quantitative descriptions of
mechanics and
hydrostatics.
The willingness to question previously held truths and search for new answers eventually resulted in a period of major scientific advancements, now known as the
Scientific Revolution of the late
17th century. The precursors to the scientific revolution can be traced back to the important developments made in
India and
Persia, including the
ellipse elliptical model of the planets based on the
heliocentrism heliocentric solar system of
gravitation developed by
Indian mathematics Indian mathematician-astronomer
Aryabhata; the basic ideas of
atomic theory developed by
Hindu and
Jaina philosophers; the theory of light being equivalent to energy particles developed by the Indian
Buddhist scholars
DignÄ?ga and
Dharmakirti; the optical theory of
light developed by
Persian people Persian Islamic science scientist Alhazen; the
Astrolabe invented by the Persian
Mohammad al-Fazari; and the significant flaws in the
Ptolemaic system pointed out by Persian scientist
Nasir al-Din al-Tusi.
As the influence of the
Islamic
Caliphate expanded to Europe, the works of Aristotle preserved by the
Arabs, and the works of the Indians and Persians, became known in Europe by the
12th century 12th and
13th century 13th centuries. This eventually lead to the scientific revolution which culminated with the publication of the ''
Philosophiae Naturalis Principia Mathematica'' in
1687 by
Isaac Newton (
1643-
1727).
The Scientific Revolution is held by most historians (e.g., Howard Margolis) to have begun in
1543, when the first printed copy of his book ''
De Revolutionibus Orbium Coelestium De Revolutionibus'' was brought from
Nuremberg to the astronomer
Nicolaus Copernicus, who had written most parts of it years earlier but hesitated to publish.
Further significant advances were made over the following century by
Galileo Galilei,
Christiaan Huygens,
Johannes Kepler, and
Blaise Pascal. During the early
17th century,
Galileo Galilei Galileo pioneered the use of experimentation to validate physical theories, which is the key idea in modern
scientific method. Galileo formulated and successfully tested several results in
dynamics (mechanics) dynamics, in particular the Law of
Inertia. In
1687,
Isaac Newton Newton published the ''
Philosophiae Naturalis Principia Mathematica Principia'', detailing two comprehensive and successful physical theories:
Newton's laws of motion, from which arise
classical mechanics; and
gravity Newton's Law of Gravitation, which describes the
fundamental force of
gravity. Both theories agreed well with experiment. The Principia also included several theories in
fluid dynamics. Classical mechanics was re-formulated and extended by
Leonhard Euler,
Joseph-Louis de Lagrange,
William Rowan Hamilton, and others, who produced new results in mathematical physics. The law of universal gravitation initiated the field of
astrophysics, which describes
astronomy astronomical phenomena using physical theories.
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After Newton defined
classical mechanics, the next great field of inquiry within physics was the nature of
electricity. Observations in the
17th century 17th and
18th century by scientists such as
Robert Boyle,
Stephen Gray (scientist) Stephen Gray, and
Benjamin Franklin created a foundation for later work. These observations also established our basic understanding of electrical charge and
electric current current.
In
1821,
Michael Faraday integrated the study of
magnetism with the study of electricity. This was done by demonstrating that a moving
magnet induced an
electric current in a
conductor (material) conductor. Faraday also formulated a physical conception of
electromagnetic fields.
James Clerk Maxwell built upon this conception, in
1864, with an interlinked set of 20 equations that explained the interactions between
electric field electric and
magnetic field. These 20 equations were later reduced, using
vector calculus, to a set of
Maxwell's equations four equations by
Oliver Heaviside.
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1905.html" title="Meaning of left|150px|[[Albert Einstein">thumb|left|150px|[[Albert Einstein in
1905">left|150px|[[Albert Einstein">thumb|left|150px|[[Albert Einstein in
1905
In addition to other electromagnetic phenomena, Maxwell's equations also can be used to describe
light. Confirmation of this observation was made with the
1888 discovery of
radio by
Heinrich Hertz and in
1895 when
Wilhelm Roentgen detected
X rays. The ability to describe light in electromagnetic terms helped serve as a springboard for
Albert Einstein's publication of the theory of
special relativity. This theory combined classical mechanics with Maxwell's equations.
The theory of
special relativity unifies space and time into a single entity,
spacetime. Relativity prescribes a different transformation between
inertial frame of reference reference frames than classical mechanics; this necessitated the development of relativistic mechanics as a replacement for classical mechanics. In the regime of low (relative) velocities, the two theories agree. Einstein built further on the special theory by including gravity into his calculations, and published his theory of
general relativity in
1915.
One part of the theory of general relativity is
Einstein's field equation. This describes how the ''stress-energy tensor'' creates curvature of
spacetime and forms the basis of general relativity. Further work on Einstein's field equation produced results which predicted the
Big Bang,
black holes, and the
expanding universe. Einstein believed in a static universe and tried (and failed) to fix his equation to allow for this. However, by
1929 Edwin Hubble's astronomical observations suggested that the universe is expanding.
From the late
17th century onwards,
thermodynamics was developed by
Robert Boyle Boyle,
Thomas Young (scientist) Young, and many others. In
1733,
Daniel Bernoulli Bernoulli used statistical arguments with classical mechanics to derive thermodynamic results, initiating the field of
statistical mechanics. In
1798,
Benjamin Thompson Thompson demonstrated the conversion of mechanical work into heat, and in
1847 James Joule Joule stated the law of conservation of
energy, in the form of heat as well as mechanical energy.
Ludwig Boltzmann, in the 19th century, is responsible for the modern form of statistical mechanics.
In
1895,
Wilhelm Röntgen Röntgen discovered
X-rays, which turned out to be high-frequency electromagnetic radiation.
Radioactivity was discovered in
1896 by
Henri Becquerel, and further studied by
Maria Sklodowska-Curie Marie Curie,
Pierre Curie, and others. This initiated the field of
nuclear physics.
In
1897,
J.J. Thomson Joseph J. Thomson discovered the
electron, the elementary particle which carries electrical current in
electrical circuit circuits. In
1904, he proposed the first model of the
atom, known as the
atom/plum pudding plum pudding model. (The existence of the atom had been proposed in
1808 by
John Dalton.)
These discoveries revealed that the assumption of many physicists that atoms were the basic unit of
matter was flawed, and prompted further study into the structure of
atoms.
Image:Ernest Rutherford.jpg Ernest_Rutherford.html" title="Meaning of thumb thumb|right|150px|[[Ernest Rutherford.html" title="Meaning of right|150px|[[Ernest Rutherford">thumb|right|150px|[[Ernest Rutherford">right|150px|[[Ernest Rutherford">thumb|right|150px|[[Ernest Rutherford
In
1911,
Ernest Rutherford deduced from
rutherford scattering scattering experiments the existence of a compact atomic nucleus, with positively charged constituents dubbed
protons.
neutron Neutrons, the neutral nuclear constituents, were discovered in
1932 by
James Chadwick Chadwick. The equivalence of mass and energy (Einstein, 1905) was spectacularly demonstrated during
World War II, as research was conducted by each side into
nuclear physics, for the purpose of creating a
nuclear weapon nuclear bomb. The German effort, led by Heisenberg, did not succeed, but the Allied
Manhattan Project reached its goal. In America, a team led by
Enrico Fermi Fermi achieved the first man-made
nuclear chain reaction in
1942, and in
1945 the world's first
nuclear weapon nuclear explosive was detonated at
Trinity site, near
Alamogordo,
New Mexico.
In
1900,
Max Planck published his explanation of
blackbody radiation. This equation assumed that radiators are
quantum quantized in nature, which proved to be the opening argument in the edifice that would become
quantum mechanics.
Beginning in
1900,
Max Planck Planck, Einstein,
Niels Bohr, and others developed
quantum theories to explain various anomalous experimental results by introducing discrete energy levels. In
1925,
Werner Heisenberg Heisenberg and
1926,
Erwin Schrödinger Schrödinger and
Paul Dirac formulated
quantum mechanics, which explained the preceding heuristic quantum theories. In quantum mechanics, the outcomes of physical measurements are inherently
probability probabilistic; the theory describes the calculation of these probabilities. It successfully describes the behavior of matter at small distance scales. During the
1920s Erwin Schrödinger,
Werner Heisenberg, and
Max Born were able to formulate a consistent picture of the chemical behavior of matter, a complete theory of the electronic structure of the atom, as a byproduct of the quantum theory.
Image:Richard feynman.jpg Richard_Feynman.html" title="Meaning of thumb thumb|left|150px|[[Richard Feynman.html" title="Meaning of left|150px|[[Richard Feynman">thumb|left|150px|[[Richard Feynman">left|150px|[[Richard Feynman">thumb|left|150px|[[Richard Feynman
Quantum field theory was formulated in order to extend quantum mechanics to be consistent with special relativity. It was devised in the late
1940s with work by
Richard Feynman,
Julian Schwinger,
Sin-Itiro Tomonaga, and
Freeman Dyson. They formulated the theory of
quantum electrodynamics, which describes the electromagnetic interaction, and successfully explained the
Lamb shift. Quantum field theory provided the framework for modern
particle physics, which studies
fundamental forces and elementary particles.
Chen Ning Yang and
Tsung-Dao Lee, in the
1950s, discovered an unexpected
asymmetry in the decay of a
subatomic particle. In
1954, Yang and
Robert Mills (physicist) Robert Mills then developed a class of
gauge theory gauge theories which provided the framework for understanding the nuclear forces. The theory for the
strong nuclear force was first proposed by
Murray Gell-Mann. The
electroweak force, the unification of the
weak nuclear force with electromagnetism, was proposed by
Sheldon Lee Glashow,
Abdus Salam and
Steven Weinberg and confirmed in
1964 by
James Watson Cronin and
Val Fitch. This led to the so-called
Standard Model of particle physics in the
1970s, which successfully describes all the elementary particles observed to date.
Quantum mechanics also provided the theoretical tools for
condensed matter physics, whose largest branch is
solid state physics. It studies the physical behavior of solids and liquids, including phenomena such as
crystal structures,
semiconductor semiconductivity, and
superconductor superconductivity. The pioneers of condensed matter physics include
Felix Bloch Bloch, who created a quantum mechanical description of the behavior of electrons in crystal structures in
1928. The transistor was developed by physicists
John Bardeen,
Walter Houser Brattain and
William Bradford Shockley in
1947 at
Bell Labs Bell Telephone Laboratories.
The two themes of the
20th century, general relativity and quantum mechanics, appear inconsistent with each other. General relativity describes the
universe on the scale of
planets and
solar systems while quantum mechanics operates on sub-atomic scales. This challenge is being attacked by
string theory, which treats
spacetime as composed, not of points, but of one-dimensional objects,
string theory strings. Strings have properties like a common string (e.g.,
Tension (mechanics) tension and
vibration). The theories yield promising, but not yet testable results. The search for experimental verification of string theory is in progress.
The United Nations have declared the year
2005, the centenary of Einstein's
annus mirabilis, as the
World Year of Physics.
Image:Witten.jpg thumb|right|Edward Witten
Future directions
{{main|Unsolved problems in physics}}
Research in physics is progressing constantly on a large number of fronts, and is likely to do so for the foreseeable future.
In condensed matter physics, the biggest unsolved theoretical problem is the explanation for
high-temperature superconductivity. Strong efforts, largely experimental, are being put into making workable
spintronics and
quantum computers.
In particle physics, the first pieces of experimental evidence for physics beyond the
Standard Model have begun to appear. Foremost amongst these are indications that
neutrinos have non-zero
mass. These experimental results appear to have solved the long-standing
solar neutrino problem in solar physics. The physics of massive neutrinos is currently an area of active theoretical and experimental research. In the next several years,
particle accelerators will begin probing energy scales in the
TeV range, in which experimentalists are hoping to find evidence for the
Higgs boson and
supersymmetry supersymmetric particles.
Theoretical attempts to unify
quantum mechanics and
general relativity into a single theory of
quantum gravity, a program ongoing for over half a century, have not yet borne fruit. The current leading candidates are
M-theory developed by
Edward Witten and
loop quantum gravity.
Many
astronomy astronomical and
cosmology cosmological phenomena have yet to be satisfactorily explained, including the existence of
GZK paradox ultra-high energy cosmic rays, the
baryon asymmetry, the
accelerating universe acceleration of the universe and the
galaxy rotation problem anomalous rotation rates of galaxies.
Although much progress has been made in high-energy, quantum, and astronomical physics, many everyday phenomena, involving
complex systems complexity,
chaos, or
turbulence are still poorly understood. Complex problems that seem like they could be solved by a clever application of dynamics and mechanics, such as the formation of sandpiles, nodes in trickling
water, the shape of water
droplets, mechanisms of
surface tension catastrophe theory catastrophes, or self-sorting in shaken heterogeneous collections are unsolved. These complex phenomena have received growing attention since the 1970s for several reasons, not least of which has been the availability of modern
mathematics mathematical methods and
computers which enabled
complex systems to be modeled in new ways. The
interdisciplinary relevance of complex physics has also increased, as exemplified by the study of
turbulence in
aerodynamics or the
observation of
pattern formation in
biology biological systems. In 1932,
Horace Lamb correctly prophesized:
''I am an old man now, and when I die and go to heaven there are two matters on which I hope for enlightenment. One is quantum electrodynamics, and the other is the turbulent motion of fluids. And about the former I am rather optimistic.''
Notes
#{{note|big bang}}Alpher, Herman, and Gamow. ''Nature'' '''162''',774 (1948). [http://nobelprize.org/physics/laureates/1978/wilson-lecture.pdf Wilson's
1978 Nobel lecture]
#{{note|parity}}See also: [http://cwp.library.ucla.edu/Phase2/Wu,_Chien_Shiung@841234567.html C.S. Wu's contribution to the overthrow of the conservation of parity]
#{{note|gauge theories}}Yang, Mills
1954 ''
Physical Review'' '''95''', 631; Yang, Mills 1954 ''Physical Review'' '''96''', 191.
Further reading
Popular Reading
*{{cite book | author=
Stephen Hawking Hawking, Stephen | title=
A Brief History of Time | publisher=Bantam | year=1988 | id=ISBN 0553109537}}
*{{cite book | author=
Richard Feynman Feynman, Richard | title=Character of Physical Law | publisher=Random House | year=1994 | id=ISBN 0679601279}}
*{{cite book | author=
Roger Penrose Penrose, Roger | title=Road to Reality: A Complete Guide to the Laws of the Universe | publisher=Knopf | year=2004 | id=ISBN 0-679-45443-8}}
*{{cite book | author=
Brian Greene Greene, Brian | title=
The Elegant Universe The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory | publisher=Vintage | year=2000 | id=ISBN 0375708111}}
*{{cite book | author=
Michio Kaku Kaku, Michio | title=
Hyperspace (book) Hyperspace : A Scientific Odyssey Through Parallel Universes, Time Warps, and the 10th Dimension | publisher=Anchor | year=1995 | id=ISBN 0385477058}}
*{{cite book | author=Walker, Jearl | title=The Flying Circus of Physics | publisher=Wiley | year=1977 | id=ISBN 047102984X}}
*{{cite book | author=Leggett, Anthony | title=The Problems of Physics | publisher=Oxford University Press | year=1988 | id=ISBN 0192891863}}
*{{cite book | author=Rogers, Eric | title=Physics for the Inquiring Mind: The Methods, Nature, and Philosophy of Physical Science | publisher=Princeton University Press | year=1960| id=ISBN 069108016X}}
University Level Textbooks
= Introductory
=
*{{cite book | author=Feynman, Richard | title=
The Feynman Lectures on Physics Feynman Lectures on Physics | publisher=Addison-Wesley | year=1989 | id=ISBN 0201510030}}
*{{cite book | author=Hewitt, Paul | title=Conceptual Physics with Practicing Physics Workbook (9th ed.) | publisher=Addison Wesley | year=2001 | id=ISBN 0321052021}}
*{{cite book | author=Giancoli, Douglas | title=Physics: Principles with Applications (6th ed.) | publisher=Prentice Hall | year=2005 | id=ISBN 0130606200}}
*{{cite book | author=Serway, Raymond A.; Jewett, John W. | title=Physics for Scientists and Engineers (6th ed.) | publisher=Brooks/Cole | year=2004 | id=ISBN 0534408427}}
*{{cite book | author=Tipler, Paul | title=Physics for Scientists and Engineers: Mechanics, Oscillations and Waves, Thermodynamics (5th ed.) | publisher=W. H. Freeman | year=2004 | id=ISBN 0716708094}}
*{{cite book | author=Tipler, Paul | title=Physics for Scientists and Engineers: Electricity, Magnetism, Light, and Elementary Modern Physics (5th ed.) | publisher=W. H. Freeman | year=2004 | id=ISBN 0716708108}}
*{{cite book | author=Wilson, Jerry; Buffa, Anthony | title=College Physics (5th ed.) | publisher=Prentice Hall | year=2002 | id=ISBN 0130676446}}
*{{cite book |author=Resnick, Halliday, Walker| title=Fundamentals of Physics}}
= Undergraduate
=
*{{cite book | author=Thornton, Stephen T.; Marion, Jerry B. | title=Classical Dynamics of Particles and Systems (5th ed.) | publisher=Brooks Cole | year=2003 | id=ISBN 0534408966}}
*{{cite book | author=Hecht, Eugene | title=Optics (4th ed.) | publisher=Pearson Education | year=2001 | id=ISBN 0805385665}}
*{{cite book | author=Griffiths, David J.|title=Introduction to Electrodynamics (3rd ed.)| publisher=Prentice Hall |year=1998 |id=ISBN 013805326X}}
*{{cite book | author=Griffiths, David J. | title=Introduction to Elementary Particles | publisher=Wiley, John & Sons, Inc | year=1987 | id=ISBN 0471603864}}
*{{cite book | author=Griffiths, David J.|title=Introduction to Quantum Mechanics (2nd ed.) | publisher=Prentice Hall |year=2004 |id=ISBN 013805326X}}
*{{cite book | author=Kroemer, Herbert; Kittel, Charles | title=Thermal Physics (2nd ed.) | publisher=W. H. Freeman Company | year=1980 | id=ISBN 0716710889}}
*{{cite book | author=Liboff, Richard L. | title=Introductory Quantum Mechanics | publisher=Addison-Wesley | year=2002 | id=ISBN 0805387145}}
*{{cite book | author=Perkins, Donald H. | title=Introduction to High Energy Physics | publisher=Cambridge University Press | year=1999 | id=ISBN 0521621968}}
*{{cite book | author=Schutz, Bernard F. | title=A First Course in General Relativity | publisher=Cambridge University Press | year=1984 | id=ISBN 0521277035}}
*{{cite book | author=Taylor, Edwin F.;
John Archibald Wheeler Wheeler, John Archibald | title=Spacetime Physics: Introduction to Special Relativity (2nd ed.) | publisher=W.H. Freeman | year=1992 | id=ISBN 0716723271}}
*{{cite book | author=Taylor, Edwin F.; Wheeler, John Archibald | title=Exploring Black Holes: Introduction to General Relativity | publisher=Addison Wesley | year=2000 | id=ISBN 020138423X}}
*{{cite book | author=Bergmann, Peter G.| title=Introduction to the Theory of Relativity| publisher=Dover Publications | year=1976 | id=ISBN 0486632822}}
*{{cite book | author=
David Bohm Bohm, David | title=Quantum Theory | publisher=Dover Publications | year=1989 | id=ISBN 0486659690}}
*{{cite book | author=Eisberg, Robert; Resnick, Robert | title=Quantum Physics of Atoms, Molecules, Solids, Nuclei, and Particles (2nd ed.) | publisher=Wiley | year=1985 | id=ISBN 047187373X}}
*{{cite book | author=Tipler, Paul; Llewellyn, Ralph | title=Modern Physics (4th ed.) | publisher=W. H. Freeman | year=2002 | id=ISBN 0716743450}}
= Graduate
=
*{{cite book | author=Goldstein, Herbert | title=Classical Mechanics | publisher=Addison Wesley | year=2002 | id=ISBN 0201657023}}
*{{cite book | author=Huang, Kerson | title=Statistical Mechanics | publisher=Wiley, John & Sons, Inc | year=1990 | id=ISBN 0471815187}}
*{{cite book | author=Jackson, John D. | title=Classical Electrodynamics (3rd ed.) | publisher=Wiley | year=1998 | id=ISBN 047130932X}}
*{{cite book | author=
Lev Landau Landau, L. D.; Lifshitz, E. M. | title=Mechanics and Electrodynamics, Vol. 1 | publisher=Franklin Book Company, Inc | year=1972 | id=ISBN 008016739X}}
*{{cite book | author=Landau, L. D.; Lifshitz, E. M. | title=Course of Theoretical Physics | publisher=Butterworth-Heinemann | year=1976 | id=ISBN 0750628960}}
*{{cite book | author=Joos, Georg; Freeman, Ira M. | title=Theoretical Physics | publisher=Dover Publications | year=1987 | id=ISBN 0486652270}}
*{{cite book | author=Arfken, George B.; Weber, Hans J. | title=Mathematical Methods for Physicists (5th ed.) | publisher=Academic Press | year=2000 | id=ISBN 0120598256}}
*{{cite book | author=Merzbacher, Eugen | title=Quantum Mechanics | publisher=Wiley, John & Sons, Inc | year=1998 | id=ISBN 0471887021}}
*{{cite book | author=Peskin, Michael E.; Schroeder, Daniel V. | title=Introduction to Quantum Field Theory | publisher=Perseus Publishing | year=1994 | id=ISBN 0201503972}}
*{{cite book | author=Wald, Robert M. | title=General Relativity | publisher=University of Chicago Press | year=1984 | id=ISBN 0226870332}}
*{{cite book | author=
Kip Thorne Thorne, Kip S.; Misner, Charles W.; Wheeler, John Archibald | title=Gravitation | publisher=W.H. Freeman | year=1973 | id=ISBN 0716703440}}
*{{cite book | author=
Steven Weinberg Weinberg, Stephen | title=Gravitation and Cosmology: Principles and Applications of the General Theory of Relativity | publisher=Wiley, John & Sons, Incorporated | year=1972 | id=ISBN 0471925675}}
= History
=
*{{cite book | author=Cropper, William H. | title=Great Physicists : The Life and Times of Leading Physicists from Galileo to Hawking | publisher=Oxford University Press | year=2004 | id=ISBN 0195173244}}
*{{cite book | author=
George Gamow Gamow, George | title=The Great Physicists from Galileo to Einstein | publisher=Dover Publications | year=1988 | id=ISBN 0486257673}}
*{{cite book | author=Heilbron, John L. | title=The Oxford Guide to the History of Physics and Astronomy | publisher=Oxford University Press | year=2005 | id=ISBN 0195171985}}
See also
*
Glossary of classical physics
*
List of basic physics topics
*
List of physics topics
*
Unsolved problems in physics
*
Philosophy of physics
*
Physics symbols
External links
{{Wikibooks}}
{{Wikibookspar|Wikiversity|School of Physics}}
{{Wiktionary}}
{{Commonscat}}
General
-
Physics and Math Textbooks Numerous online textbooks on Physics and Mathematics
-
Usenet Physics FAQ. A
FAQ compiled by sci.physics and other physics newsgroups.
-
Physics.org - Web portal run by the [http://www.iop.org/ Institute of Physics].
-
World of Physics. An online encyclopedic dictionary of physics.
-
Website of the Nobel Prize in Physics.
-
Physics Today - Your daily physics news and research source
-
The Skeptic's Guide to Physics
-
PlanetPhysics Online Physics
-
Physics 2005: Website of the
World Year of Physics 2005
Organizations
-
AIP.org Website of the
American Institute of Physics
-
APS.org Website of the
American Physical Society
-
SPS National Website of the
Society of Physics Students
Forums
-
Advanced Physics Forums Physics Forum for Physics Majors
-
Physics Forums Physics Forum
* [news://sci.physics sci.physics] The
Usenet general physics
newsgroup.
-
Physics Math Forums Physics, Math, and Philosophy Forums
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Image:Galileo2.png Galileo_Galilei left|thumb|130px|[[Galileo Galilei|Galileo,
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'''Physics''' (from the
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science of
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