Planck unit
In physics, Planck units are physical units of measurement defined exclusively in terms of five universal physical constants listed below, in such a manner that these five physical constants take on the numerical value of 1 when expressed in terms of these units. Planck units have profound significance for theoretical physics since they elegantly simplify several recurring algebraic expressions of physical law by nondimensionalization. They are particularly relevant in research on unified theories such as quantum gravity.
Originally proposed in 1899 by German physicist Max Planck, these units are also known as natural units because the origin of their definition comes only from properties of the fundamental physical theories and not from interchangeable experimental parameters. Planck units are only one system of natural units among other systems, but are considered unique in that these units are not based on properties of any prototype object or particle (that would be arbitrarily chosen), but rather on properties of free space alone.
The universal constants that Planck units, by definition, normalize to 1 are
- the gravitational constant, G,
- the reduced Planck constant, ħ,
- the speed of light in a vacuum, c,
- the Coulomb constant, (4πε0)−1 (sometimes ke or k), and
- the Boltzmann constant, kB (sometimes k).
Each of these constants can be associated with at least one fundamental physical theory: c with electromagnetism and special relativity, G with general relativity and Newtonian gravity, ħ with quantum mechanics, ε0 with electrostatics, and kB with statistical mechanics and thermodynamics.
Planck units are sometimes called "God's units", since Planck units are free of anthropocentric arbitrariness. Some physicists argue that communication with extraterrestrial intelligence would have to employ such a system of units in order to be understood. Unlike the meter and second, which exist as fundamental units in the SI system for historical reasons, the Planck length and Planck time are conceptually linked at a fundamental physical level.
Natural units help physicists to reframe questions. Frank Wilczek puts it succinctly:
It is true that the electrostatic repulsive force between two protons (alone in free space) greatly exceeds the gravitational attractive force between the same two protons. From the point of view of Planck units, however, this is not a statement about the relative strengths of the two forces; rather, it is a manifestation of the fact that the charge on the protons is approximately the Planck charge but the mass of the protons is far less than the Planck mass.

This is an excerpt from the article Planck unit from the Wikipedia free encyclopedia. A list of authors is available at Wikipedia.
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Planck units - Wikipedia, the free encyclopedia
In physics, Planck units are physical units of measurement defined exclusively in terms of five universal physical constants listed below, in such a manner that ...
en.wikipedia.org/wiki/Planck_units
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Planck time - Wikipedia, the free encyclopedia
In physics, the Planck time (tP) is the unit of time in the system of natural units known as Planck units. It is the time required for light to travel, in a vacuum, ...
en.wikipedia.org/wiki/Planck_time
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FUNDAMENTAL PLANCK UNITS
An essay on the extraction, uses and interpretation od the Planck fundamental units.
graham.main.nc.us/~bhammel/PHYS/planckunits.html
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Planck length - Wikipedia, the free encyclopedia
In physics, the Planck length, denoted ℓP, is a unit of length, equal to 1.616199( 97)×10−35 metres. It is a base unit in the system of Planck units, developed by ...
en.wikipedia.org/wiki/Planck_length
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Planck energy - Wikipedia, the free encyclopedia
In physics, Planck energy, denoted by EP, is the unit of energy in the system of natural units known as Planck units. E_\text{P} = \sqrt{\frac{\hbar c 1.956 × 109 J \  ...
en.wikipedia.org/wiki/Planck_energy
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Q: What is the Planck length? What is its relevance? | Ask a ...
May 25, 2013 ... So, why not choose units so that G=1, and then ignore it? The Planck units are set up so that G (the gravitational constant), c (the speed of light), ...
www.askamathematician.com/2013/05/q-what-is-the-planck-length-what-is-its-relevance/
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Planck Units | COSMOS
Note that we have expressed these constants in SI units: metres (m), kilograms ... These units are known as the Planck units (after Max Planck, the physicist who ...
astronomy.swin.edu.au/cosmos/P/Planck+Units
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The Planck scale: relativity meets quantum mechanics meets gravity ...
The Planck length LP is defined by taking the constants of nature and combining them in such a way that their units combine to give a length. Planck's constant ...
www.phys.unsw.edu.au/einsteinlight/jw/module6_Planck.htm
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Planck's constant - RationalWiki
The system of Planck units was designed to make the lives of quantum physicists easier still. In the Planck unit system, five basic ...
rationalwiki.org/wiki/Planck's_constant
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The Planck Length
Planck noted that apart from numerical factors there is a unique way to use these constants to define units of length, time, and mass. For example, we can define ...
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Planck unit in science
Max Planck Research Department for Structural Dynamics
Max Planck Research Department for Structural Dynamics at the University of Hamburg. The Max Planck Research Department for Structural Dynamics at the ...
Contact - Max Planck Research Department for Structural Dynamics
Contact. Max Planck unit for Structural Dynamics at the University of Hamburg Dr . Monika Kaempfe, Research Coordinator c/o DESY, Bldg. 99, Room 01.077
Planck time - Wikipedia, the free encyclopedia
In physics, the Planck time (tP) is the unit of time in the system of natural units known as Planck units. It is the time ... Georgia State University. 19 June 2005.
Max Planck Society - Wikipedia, the free encyclopedia
In 2006, the Times Higher Education Supplement rankings of non-university .... Max Planck Research Unit for Enzymology of Protein Folding, Halle/Saale · Max  ...
Planck Units | COSMOS
Planck units ... These units are known as the Planck units (after Max Planck, the physicist who first ... Study Astronomy Online at Swinburne University
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The Max Planck Institute of Neurobiology in Martinsried, Germany and The Edmond and Lily Safra Center for Brain Sciences at the Hebrew University of ...
Planck's constant
Due to his insight, we call this unit Planck's constant (h). The word quantum derives from quantity and refers to a small packet of action or process, the smallest ...
Max Planck Institute of Economics
It is organized into two research units, the Evolutionary Economics Group ... The Max Planck Institute of Economics and the Friedrich Schiller University in Jena ...
Bert Sakmann - Max-Planck-Institut für Neurobiologie
1971-1973: Britisch Council Fellow, Department of Biophysics, University ... 1983 : Member of the Max Planck Society, Head of the Membrane Biology Unit.
Dr. Lars Redecke - Chemie - Universität Hamburg
Study of Chemistry at the University of Hamburg; Diploma Thesis (2000) and ... Research Assistant at the Max-Planck unit for Structural Moelcular Biology, ...
Books on the term Planck unit
String Theory For Dummies
String Theory For Dummies
Andrew Zimmerman Jones, 2009
Planck length: 10–35 meters (if a hydrogen atom were as big as our galaxy, the Planck length would be the size of a human ... Some of these units were first proposed in 1899 by Max Planck himself, before either relativity or quantum physics.
Our Mathematical Universe: My Quest for the Ultimate Nature of Reality
Our Mathematical Universe: My Quest for the Ultimate Nature of Reality
Max Tegmark, 2014
“Tegmark offers a fascinating exploration of multiverse theories, each one offering new ways to explain ‘quantum weirdness’ and other mysteries that have plagued physicists, culminating in the idea that our physical world is ‘a giant mathematical object’ shaped by geometry and symmetry. Tegmark’s writing is lucid, enthusiastic, and outright enterta...
Mathematics as Metaphor: Selected Essays of Yuri I. Manin
Mathematics as Metaphor: Selected Essays of Yuri I. Manin
I͡U. I. Manin, 2007
Planck units and the Problem of a Unified Physical Theory In Newtonian physics there are no other natural units besides G. The speed of light c can be declared a natural unit only within a new theory which postulates its particular role as the ...
Chemistry For Dummies
Chemistry For Dummies
John T. Moore, 2011
See how chemistry works in everything from soaps to medicines to petroleumWe're all natural born chemists. Every time we cook, clean, take a shower, drive a car, use a solvent (such as nail polish remover), or perform any of the countless everyday activities that involve complex chemical reactions we're doing chemistry! So why do so many ...
Encyclopedia of Physics
Encyclopedia of Physics
Joe Rosen, 2009
254 Planck scale and of [angle][ ANGULAR MOMENTUM]. The Planck constant determines the fundamental unit of angular momentum, including SPIN. All angular momenta are integer or half-integer multiples of h/(2π). The Planck constant ...
The Fabric of the Cosmos: Space, Time, and the Texture of Reality
The Fabric of the Cosmos: Space, Time, and the Texture of Reality
Brian Greene, 2005
As a boy, Brian Greene read Albert Camus' The Myth of Sisyphus and was transformed. Camus, in Greene's paraphrase, insisted that the hero triumphs "by relinquishing everything beyond immediate experience." After wrestling with this idea, however, Greene rejected Camus and realized that his true idols were physicists; scientists ...
Motion Mountain - old4
Motion Mountain - old4
Christoph Schiller
2 Name Definition Value the Planck temperature TPl = ħc5/Gk2 = 1.4171(91) ⋅ 1032 K Trivial units the Planck velocity Pl = c = 0.3Gm/s the Planck angular momentum LPl = ħ = 1.1⋅10−34Js the Planck action SaPl = ħ = 1.1⋅10−34Js the  ...
The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos
The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos
Brian Greene, 2011
Amazon Best Books of the Month, January 2011: Take any of physics' major theories of the fundamental nature of the universe, extrapolate its math to the logical extreme, and you get some version of a (so far unobservable) parallel universe. And who better to navigate these hypothetical versions of the "multiverse" than Brian Greene? ...
Mass and Motion in General Relativity
Mass and Motion in General Relativity
Luc Blanchet, Alessandro Spallicci, Bernard Whiting, 2011
2.3 Planck units, Natural Units, and Atomic Units The Planck units are perhaps the best known of the natural unit systems, and for this reason provide a useful contrast to the SI. In usual formulations, the Planck units correspond to the ...
Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the 10th Dimension
Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the 10th Dimension
Michio Kaku, 1995
How many dimensions do you live in? Three? Maybe that's all your commonsense sense perception perceives, but there is growing and compelling evidence to suggest that we actually live in a universe of ten real dimensions. Kaku has written an extraordinarily lucid and thought-provoking exploration of the theoretical and empirical bases of a ten-...
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Planck unit
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Hands-on planck units tutorial - Modern and Theoretical Physics - Science Forums
Page 1 of 2 - Hands-on Planck units tutorial - posted in Modern and Theoretical Physics: Planck units like the mass and length come up all over the place in modern physics---they are not the only system, there are other convenient special purpose units, but they are worth getting familiar with.Using the google calculator we can take a kind of almost experimental approach to Planck units, explore, build up our concepts, try them out. It is easy---a few posts will show what I mean. So heres...
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Comments by the Max Planck Institute for Intellectual Property and ...
ec.europa.eu/competition/antitrust/art82/drexl.pdf
Max Planck Institute for Tax Law and Public Finance - Prof. Dr. Kai A. Konrad
Prof. Dr. Kai A. Konrad / Director at the Max Planck Institute for Tax Law and Public Finance
www.tax.mpg.de/en/pub/public_economics/public_economics_people/prof_dr_kai_a_konrad.cfm
Max Planck Institute of Immunbiology and Epigenetics | Mediator der transkriptionellen
www1.ie-freiburg.mpg.de/7978/research_report_449475
Max Planck Institute for Comparative and International Private Law - Russia and other CIS-States
www.mpipriv.de/en/pub/research/foreign_law_regional_centres/russia_and_other_cis_states.cfm
Max Planck Institute for Comparative and International Private Law - Pißler Knut Benjamin
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