# Portal:Physics

*https://en.wikipedia.org/wiki/Portal:Physics*

Physics Portal Main Page |
Physics Textbook |
Wikiprojects and things to do |

*The Physics Portal*

**
Physics** (from
Ancient Greek: φυσική (ἐπιστήμη),
romanized: *physikḗ (epistḗmē)*,
lit. 'knowledge of nature', from φύσις *phýsis* 'nature') is the
natural science that studies
matter, its
motion and behavior through
space and time, and the related entities of
energy and
force. Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the
universe behaves.

Physics is one of the oldest
academic disciplines and, through its inclusion of
astronomy, perhaps *the* oldest. Over much of the past two millennia, physics,
chemistry,
biology, and certain branches of
mathematics were a part of
natural philosophy, but during the
Scientific Revolution in the 17th century these natural sciences emerged as unique research endeavors in their own right. Physics intersects with many
interdisciplinary areas of research, such as
biophysics and
quantum chemistry, and the boundaries of physics are not
rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in academic disciplines such as mathematics and
philosophy.

Advances in physics often enable advances in new
technologies. For example, advances in the understanding of
electromagnetism,
solid-state physics, and
nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as
television,
computers,
domestic appliances, and
nuclear weapons; advances in
thermodynamics led to the development of
industrialization; and advances in
mechanics inspired the development of
calculus. (**
Full article...**)

**
Leonhard Euler** (
/ˈɔɪlər/
*OY-lər*; German:
[ˈɔʏlɐ] (
listen); 15 April 1707 – 18 September 1783) was a Swiss
mathematician,
physicist,
astronomer,
geographer,
logician and
engineer who made important and influential discoveries in many branches of
mathematics, such as
infinitesimal calculus and
graph theory, while also making pioneering contributions to several branches such as
topology and
analytic number theory. He also introduced much of the modern mathematical terminology and
notation, particularly for
mathematical analysis, such as the notion of a
mathematical function. He is also known for his work in
mechanics,
fluid dynamics,
optics,
astronomy and
music theory.

**Full article...**)

## Did you know -

- ...that while
**Albert Einstein**is most famous for his Theory of Relativity, he was awarded the Nobel Prize for his explanation of the photoelectric effect?

- ...that
gravitational tidal accelerations are the result of the curvature of
**spacetime**?

- ...that the blue glow of the
Cherenkov effect is due to electrons moving faster than the
**speed of light**in water?

## Selected image -

### Difference between classical and modern physics

While physics aims to discover universal laws, its theories lie in explicit domains of applicability. Loosely speaking, the laws of classical physics accurately describe systems whose important length scales are greater than the atomic scale and whose motions are much slower than the speed of light. Outside of this domain, observations do not match their predictions. Albert Einstein contributed the framework of special relativity, which replaced notions of absolute time and space with spacetime and allowed an accurate description of systems whose components have speeds approaching the speed of light. Max Planck, Erwin Schrödinger, and others introduced quantum mechanics, a probabilistic notion of particles and interactions that allowed an accurate description of atomic and subatomic scales. Later, quantum field theory unified quantum mechanics and special relativity. General relativity allowed for a dynamical, curved spacetime, with which highly massive systems and the large-scale structure of the universe can be well-described. General relativity has not yet been unified with the other fundamental descriptions; several candidate theories of quantum gravity are being developed.

## Related portals

In
mathematics, the **
Dirac delta function** (**δ function**) is a
generalized function or
distribution introduced by physicist
Paul Dirac. It is called a function, although it is not a function on the level you would expect, that is, it is not a function **R** → **C**, but a function on the space of
test functions. It is used to model the density of an idealized
point mass or
point charge as a
function equal to zero everywhere except for zero and whose
integral over the entire real line is equal to one. As there is no function that has these properties, the computations made by theoretical physicists appeared to mathematicians as nonsense until the introduction of distributions by
Laurent Schwartz to formalize and validate the computations. As a distribution, the Dirac delta function is a
linear functional that maps every function to its value at zero. The
Kronecker delta function, which is usually defined on a discrete domain and takes values 0 and 1, is a discrete analog of the Dirac delta function.

**unit impulse**symbol, may be regarded through its Laplace transform, as coming from the boundary values of a complex analytic function of a complex variable. The formal rules obeyed by this function are part of the operational calculus, a standard tool kit of physics and engineering. In many applications, the Dirac delta is regarded as a kind of limit (a weak limit) of a sequence of functions having a tall spike at the origin (in theory of distributions, this is a true limit). The approximating functions of the sequence are thus "approximate" or "nascent" delta functions. (

**Full article...**)

## May anniversaries

- May 1, 1960 - U-2 spy plane shot down
- May 6, 1937 - Hindenburg fire
- May 9, 1012 BC – Solar Eclipse seen at Ugarit, 6:09–6:39 PM.
- May 9, 1904 – City of Truro, a steam locomotive exceeds 100 mph (160 km/h).
- May 10, 1946 – V-2 rocket's first successful launch at White Sands Proving Ground
- May 10, 1960 – The nuclear submarine
USS
*Triton*completes Operation Sandblast, the first underwater circumnavigation of the earth. - May 11, 1862 –
American Civil War: The ironclad
CSS
*Virginia*is scuttled in Virginia. - May 11, 1995 – In New York City, over 170 countries extend Nuclear Nonproliferation Treaty indefinitely, without conditions.
- May 11, 1998 – India conducts three underground nuclear tests, including a thermonuclear device.
- May 14, 2018 - Ennackal Chandy George Sudarshan died.
- May 16, 1960 - Theodore Maiman operates the first optical laser, at Hughes Research Laboratories in Malibu, California.
- May 16, 1969 – Venera 5, a Soviet spaceprobe, lands on Venus.
- May 17, 1865 – The International Telegraph Union is established.
- May 18, 1998 - Microsoft sued by US Government
- May 19, 1943 - RAF uses bouncing bombs in combat
- May 20, 1932 - Amelia Earhart crosses Atlantic Ocean
- May 26, 1972 - President Nixon and Leonid Brezhnev sign nuclear weapon non-proliferation pact.
- May 24, 1844 - First official telegraph message is sent by Samuel Morse.
- May 27, 1937 - Grand opening, Golden Gate Bridge
- May 28, 1998 – Pakistan conducts five underground nuclear tests, named Chagai-I.

### Births

- May 6, 1872 - Willem de Sitter, physicist, mathematician, and astronomer
- May 9, 1931 – Vance Brand, astronaut
- May 10, 1746 – Gaspard Monge, mathematician
- May 10, 1788 – Augustin-Jean Fresnel physicist
- May 10, 1963 – Lisa Nowak, astronaut
- May 11, 1918 – Richard Feynman, physicist
- May 14, 1686 - Gabriel Fahrenheit, physicist and engineer
- May 21, 1921 - Andrei Sakharov, nuclear physicist
- May 7,1861 - Rabindranath Tagore, poet, patriotist, and philosopher

### Deaths

- May 10, 1482 – Paolo dal Pozzo Toscanelli, mathematician and astronomer
- May 16, 1830 – Joseph Fourier, French scientist
- May 17, 1916 – Boris Borisovich Galitzine, Russian physicist

## Categories

**Fundamentals**:
Concepts in physics |
Constants |
Physical quantities |
Units of measure |
Mass |
Length |
Time |
Space |
Energy |
Matter |
Force |
Gravity |
Electricity |
Magnetism |
Waves

**Basic physics**:
Mechanics |
Electromagnetism |
Statistical mechanics |
Thermodynamics |
Quantum mechanics |
Theory of relativity |
Optics |
Acoustics

**Specific fields**:
Acoustics |
Astrophysics |
Atomic physics |
Molecular physics |
Optical physics |
Computational physics |
Condensed matter physics |
Nuclear physics |
Particle physics |
Plasma physics

**Tools**:
Detectors |
Interferometry |
Measurement |
Radiometry |
Spectroscopy |
Transducers

**Background**:
Physicists |
History of physics |
Philosophy of physics |
Physics education |
Physics journals |
Physics organizations

**Other**:
Physics in fiction |
Pseudophysics |
Physics lists |
Physics software |
Physics stubs

## General images

**The following are images from various physics-related articles on Wikipedia.**

## More recognized content

This is a list of recognized content, updated weekly by
JL-Bot (
talk ·
contribs). There is no need to edit the list yourself. If an article is missing from the list, make sure it is
tagged (e.g. {{
WikiProject Physics}}) or
categorized correctly. See
WP:RECOG for configuration options. |

### Good articles

- 2019 redefinition of the SI base units
- Harold Agnew
- Samuel King Allison
- Luis Walter Alvarez
- Ames Project
- Elda Emma Anderson
- Antimetric electrical network
- Aristotle
- Astronomy
- Atmosphere of Uranus
- Atomic theory
- Avogadro constant
- Robert Bacher
- Kenneth Bainbridge
- Violin acoustics
- Hans Bethe
- Bicycle and motorcycle dynamics
- Francis Birch (geophysicist)
- Black hole
- Aage Bohr
- Max Born
- Bouncing ball
- Norris Bradbury
- Hugh Bradner
- Celestial spheres
- Robert F. Christy
- Clapotis
- John Cockcroft
- Arthur Compton
- CT scan
- Condensed matter physics
- Edward Condon
- Corbett's electrostatic machine
- Edward Creutz
- Charles Critchfield
- Marie Curie
- Joan Curran
- Cyclone
- DU spectrophotometer
- Harry Daghlian
- Deep Impact (spacecraft)
- Beryl May Dent
- Diffusion damping
- Dirac delta function
- Discovery of the neutron
- Dynamics of the celestial spheres
- Earth's magnetic field
- Ecliptic
- Albert Einstein
- Einstein–Szilárd letter
- Elastance
- Electricity
- Experiments and Observations on Electricity
- Ronald Fedkiw
- Val Logsdon Fitch
- Fizeau–Foucault apparatus
- Fizeau experiment
- Flerovium
- Floating Clouds (artwork)
- Force
- Foster's reactance theorem
- James Franck
- Franklin's electrostatic machine
- Augustin-Jean Fresnel
- Frisch–Peierls memorandum
- Frog battery
- Klaus Fuchs
- Galileo Galilei
- Joseph Gelders
- Geostationary orbit
- Geothermal energy
- Gleason's theorem
- Maria Goeppert Mayer
- Alvin C. Graves
- Gravity bong
- Otto Hahn
- John T. Hayward
- Hilbert space
- History of the metric system
- A History of the Theories of Aether and Electricity
- Mujaddid Ahmed Ijaz
- Interferometry
- International System of Units
- Mary Jackson (engineer)
- Brian Josephson
- Donald William Kerst
- Kilogram
- Laser Inertial Fusion Energy
- Ernest Lawrence
- Hilde Levi
- Joel S. Levine
- Liquid crystal
- Magnetic resonance imaging
- Malaysia Airlines Flight 370 satellite communications
- John Marburger
- Leslie H. Martin
- Harrie Massey
- Maximum sustained wind
- James Clerk Maxwell
- Boyce McDaniel
- Lise Meitner
- Metric system
- Mobility analogy
- Molniya orbit
- Philip Morrison
- Nature
- Seth Neddermeyer
- Negative resistance
- John von Neumann
- Neutron magnetic moment
- Isaac Newton
- Newton's theorem of revolving orbits
- Nobel Prize in Physics
- Noctilucent cloud
- Nuclear power
- Adriana Ocampo
- Optical properties of carbon nanotubes
- PSR B1937+21
- Rudolf Peierls
- Bruno Pontecorvo
- Chanda Prescod-Weinstein
- Pythagoras
- Quantum mechanics
- Quantum Reality
- Quantum electrodynamics
- RaLa Experiment
- James Rainwater
- Norman Foster Ramsey Jr.
- Frederick Reines
- Representation theory of the Lorentz group
- George T. Reynolds
- Bruno Rossi
- Joseph Rotblat
- S-1 Executive Committee
- Safety of high-energy particle collision experiments
- Saffir–Simpson scale
- Matthew Sands
- Schiehallion experiment
- Glenn T. Seaborg
- Emilio Segrè
- Henry DeWolf Smyth
- Steam devil
- Storm surge
- Carl Størmer
- Subtle is the Lord
- Leo Szilard
- Nikola Tesla
- Thin Man (nuclear bomb)
- Charles Allen Thomas
- Ernest Titterton
- Tropical cyclone scales
- Type II supernova
- Type Ia supernova
- Type Ib and Ic supernovae
- Stanislaw Ulam
- Universe
- John Clive Ward
- Waterspout
- Katharine Way
- Weak interaction
- Alvin M. Weinberg
- Wetting
- John Archibald Wheeler
- Schuyler Wheeler
- E. T. Whittaker
- Eugene Wigner
- Robert R. Wilson
- Wind shear
- Wind power
- Leona Woods
- Wow! signal
- Wright brothers
- Chien-Shiung Wu
- Wu Zhonghua
- Wu experiment
- X-ray crystallography
- Walter Zinn

## Physics topics

Classical physics traditionally includes the fields of mechanics, optics, electricity, magnetism, acoustics and thermodynamics. The term Modern physics is normally used for fields which rely heavily on quantum theory, including quantum mechanics, atomic physics, nuclear physics, particle physics and condensed matter physics. General and special relativity are usually considered to be part of modern physics as well.

## Associated Wikimedia

## Sources

## Portals on Wikipedia