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Standard Model
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In particle physics, supersymmetry (often abbreviated SUSY) is a symmetry that relates elementary particles of one spin to another particle that differs by half a unit of spin and are known as superpartners. In Physics, the Standard Model of Particle physics is currently the best description of all experimental data The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist See also String theory Superstring theory is an attempt to explain all of the particles and Fundamental forces of nature in one theory by modelling In Theoretical physics, supergravity ( supergravity theory) is a field theory that combines the principles of Supersymmetry and General relativity Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them Symmetry generally conveys two primary meanings The first is an imprecise sense of harmonious or aesthetically-pleasing proportionality and balance such that it reflects beauty or In Quantum mechanics, spin is a fundamental property of atomic nuclei, Hadrons and Elementary particles For particles with non-zero spin In Particle physics, a superpartner is a particle related to a more standard particle by Supersymmetry. In other words, in a supersymmetric theory, for every type of boson there exists a corresponding type of fermion, and vice-versa. In Particle physics, bosons are particles which obey Bose-Einstein statistics; they are named after Satyendra Nath Bose and Albert Einstein In Particle physics, fermions are particles which obey Fermi-Dirac statistics; they are named after Enrico Fermi.
As of 2008 there is no direct evidence that supersymmetry is a symmetry of nature. Since superpartners of the particles of the Standard Model have not been observed, supersymmetry, if it exists, must be a broken symmetry allowing the 'sparticles' to be heavy. The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles " Sparticle " is a merging of the words supersymmetric and particle.
If supersymmetry exists close to the TeV energy scale, it allows the solution of two major puzzles in particle physics. Particle physics is a branch of Physics that studies the elementary constituents of Matter and Radiation, and the interactions between them One is the hierarchy problem - on theoretical grounds there are huge expected corrections to the particles' masses, which without fine-tuning will make them much larger than they are in nature. In Theoretical physics, a hierarchy problem occurs when the fundamental parameters ( couplings or masses of some Lagrangian are vastly different (usually In Theoretical physics, fine-tuning refers to circumstances when the parameters of a model must be adjusted very precisely in order to agree with observations Another problem is the unification of the weak interactions, the strong interactions and electromagnetism. Grand Unification, grand unified theory, or GUT refers to any of several very similar unified field theories or models in Physics that The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four Fundamental interactions of nature In particle physics the strong interaction, or strong force, or color force, holds Quarks and Gluons together to form Protons and Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of Another advantage of supersymmetry is that supersymmetric quantum field theory can sometimes be solved. In quantum field theory (QFT the forces between particles are mediated by other particles Supersymmetry is also a consequence of most versions of string theory, though it can exist in nature even if string theory is wrong. String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings
The Minimal Supersymmetric Standard Model is one of the best studied candidates for physics beyond the Standard Model. The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist In Physics, the Standard Model of Particle physics is currently the best description of all experimental data
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Applications
Extension of Possible Symmetry Groups
One reason that physicists explored supersymmetry is because it offers an extension to the more familiar symmetries of quantum field theory. This is a list of some of the major unsolved problems in Physics. Symmetry generally conveys two primary meanings The first is an imprecise sense of harmonious or aesthetically-pleasing proportionality and balance such that it reflects beauty or Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. These symmetries are grouped into the Poincaré group and internal symmetries and the Coleman-Mandula theorem showed that under certain assumptions, the symmetries of the S-matrix must be a direct product of the Poincaré group with a compact internal symmetry group or if there is no mass gap, the conformal group with a compact internal symmetry group. In Physics and Mathematics, the Poincaré group, named after Henri Poincaré, is the group of isometries of Minkowski spacetime The Coleman-Mandula theorem, named after Sidney Coleman and Jeffrey Mandula, is a No-go theorem in Theoretical physics. Scattering matrix redirects here For the meaning in linear electrical networks see Scattering parameters. In Quantum field theory, the mass gap is the difference in energy between the vacuum and the next highest energy state In Mathematics, conformal geometry is the study of the set of angle-preserving ( conformal) transformations on a Riemannian manifold or Pseudo-Riemannian In 1975, the Haag-Lopuszanski-Sohnius theorem showed that considering symmetry generators which satisfy anticommutation relations allows for such nontrivial extensions of space-time symmetry. Year 1975 ( MCMLXXV) was a Common year starting on Wednesday (link will display full calendar of the Gregorian calendar. In Theoretical physics, the Haag-Lopuszanski-Sohnius theorem shows that the possible symmetries of a Consistent 4-dimensional Quantum field theory In Mathematics, the commutator gives an indication of the extent to which a certain Binary operation fails to be Commutative. This extension to the Coleman-Mandula theorem prompted some physicists to study this wider class of theories.
The supersymmetry algebra
- Main article: Supersymmetry algebra
Traditional symmetries in physics are generated by objects that transform under the tensor representations of the Poincaré group and internal symmetries. In Theoretical physics, a supersymmetry algebra (or SUSY algebra) is a symmetry algebra incorporating Supersymmetry, a relation between Bosons History The word tensor was introduced in 1846 by William Rowan Hamilton to describe the norm operation in a certain type of algebraic system (eventually In Mathematics and Theoretical physics, the idea of a representation of a Lie group plays an important role in the study of continuous Symmetry In Physics and Mathematics, the Poincaré group, named after Henri Poincaré, is the group of isometries of Minkowski spacetime Supersymmetries, on the other hand, are generated by objects that transform under the spinor representations. In Mathematics and Physics, in particular in the theory of the Orthogonal groups spinors are elements of a complex vector space introduced to expand the According to the spin-statistics theorem, bosonic fields commute while fermionic fields anticommute. The spin-statistics theorem in Quantum mechanics relates the spin of a particle to the statistics obeyed by that particle In Particle physics, bosons are particles which obey Bose-Einstein statistics; they are named after Satyendra Nath Bose and Albert Einstein In Mathematics, commutativity is the ability to change the order of something without changing the end result In Particle physics, fermions are particles which obey Fermi-Dirac statistics; they are named after Enrico Fermi. In mathematics anticommutativity refers to the property of an operation being anticommutative, i In order to combine the two kinds of fields into a single algebra requires the introduction of a Z2-grading under which the bosons are the even elements and the fermions are the odd elements. In Mathematics, a Lie algebra is an algebraic structure whose main use is in studying geometric objects such as Lie groups and differentiable Manifolds Lie In Mathematics, in particular Abstract algebra, a graded algebra is an Algebra over a field (or Commutative ring) with an extra piece of structure Such an algebra is called a Lie superalgebra. In Mathematics, a Lie superalgebra is a generalisation of a Lie algebra to include a Z 2- grading.
The simplest supersymmetric extension of the Poincaré algebra contains two Weyl spinors with the following anti-commutation relation:
and all other anti-commutation relations between the Qs and Ps vanish. In Physics and Mathematics, the Poincaré group, named after Henri Poincaré, is the group of isometries of Minkowski spacetime In Mathematics and Physics, in particular in the theory of the Orthogonal groups spinors are elements of a complex vector space introduced to expand the In Mathematics, the commutator gives an indication of the extent to which a certain Binary operation fails to be Commutative. In the above expression 
are the generators of translation and σμ are the Pauli matrices. The Pauli matrices are a set of 2 × 2 complex Hermitian and unitary matrices.
There are representations of a Lie superalgebra that are analogous to representations of a Lie algebra. In the mathematical field of Representation theory, a representation of a Lie superalgebra is an action of Lie superalgebra L on a Each Lie algebra has an associated Lie group and a Lie superalgebra can sometimes be extended into representations of a Lie supergroup. The concept of supergroup is a Generalization of that of group.
The Supersymmetric Standard Model
- Main article: Minimal Supersymmetric Standard Model
Incorporating supersymmetry into the Standard Model requires doubling the number of particles since there is no way that any of the particles in the Standard Model can be superpartners of each other. The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles In Particle physics, a superpartner is a particle related to a more standard particle by Supersymmetry. With the addition of the new particles, there are many possible new interactions. The simplest possible supersymmetric model consistent with the Standard Model is the Minimal Supersymmetric Standard Model (MSSM). The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist
One of the main motivations for SUSY comes from the quadratically divergent contributions to the Higgs mass squared. The Higgs Boson is a hypothetical massive scalar Elementary particle predicted to exist by the Standard Model of Particle physics In Theoretical physics and Quantum field theory a particle's self-energy \Sigma represents the contribution to the particle's Energy, or In Particle physics, fermions are particles which obey Fermi-Dirac statistics; they are named after Enrico Fermi. The top quark is the third- generation up-type Quark with a charge of +(2/3 e. In Mathematics and Physics, a scalar field associates a scalar value which can be either mathematical in definition or physical, to every point In Particle physics, a sfermion is any of the class of spin -0 Superpartners of ordinary Fermions appearing in supersymmetric extensions Motivation and history When calculating Scattering cross sections in Particle physics, the interaction between particles can be described The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles The quantum mechanical interactions of the Higgs boson causes a large renormalization of the Higgs mass and unless there is an accidental cancellation, the natural size of the Higgs mass is the highest scale possible. This problem is known as the hierarchy problem. In Theoretical physics, a hierarchy problem occurs when the fundamental parameters ( couplings or masses of some Lagrangian are vastly different (usually Supersymmetry reduces the size of the quantum corrections by having automatic cancellations between fermionic and bosonic Higgs interactions. If supersymmetry is restored at the weak scale, then the Higgs mass is related to supersymmetry breaking which can be induced from small non-perturbative effects explaining the vastly different scales in the weak interactions and gravitational interactions.
In many supersymmetric Standard Models there is a heavy stable particle (such as neutralino) which could serve as a WIMPs (weakly interacting massive particles) dark matter candidate. In Particle physics, the neutralino is a hypothetical particle part of the doubling of the menagerie of particles predicted by supersymmetric theories In Physics and cosmology, dark matter is hypothetical Matter that does not interact with the electromagnetic force but whose presence can be inferred from The existence of a supersymmetric dark matter candidate is closely tied to R-parity. R-parity is a concept in Particle physics. In the supersymmetric extension of the Standard Model, Baryon number and Lepton number
The standard paradigm for incorporating supersymmetry into a realistic theory is to have the underlying dynamics of the theory be supersymmetric, but the ground state of the theory does not respect the symmetry and supersymmetry is broken spontaneously. In Physics, spontaneous symmetry breaking occurs when a system that is symmetric with respect to some Symmetry group goes into a Vacuum state The supersymmetry break can not be done by the particles of the MSSM. This means that there is a new sector of the theory that is responsible for the breaking. The only constraint on this new sector is that it must break supersymmetry and must give superparticles TeV scale masses. There are many models that can do this and most of their details do not matter. In order to parameterize the relevant features of supersymmetry breaking, soft SUSY breaking terms are added to the theory which break SUSY explicitly but could arise from a complete theory of supersymmetry breaking
Gauge Coupling Unification
- Main article: gauge coupling unification
One piece of evidence for supersymmetry existing at the weak scale is gauge coupling unification. In Theoretical physics, soft SUSY breaking is type of Supersymmetry breaking that does not cause Ultraviolet divergences to appear in scalar masses Grand Unification, grand unified theory, or GUT refers to any of several very similar unified field theories or models in Physics that The renormalization group evolution of the three gauge coupling constants of the Standard Model is sensitive to the particle content of the theory. In Theoretical physics, renormalization group (RG refers to a mathematical apparatus that allows one to investigate the changes of a physical system as one views In Physics, a coupling constant, usually denoted g, is a number that determines the strength of an Interaction. These coupling constants do not quite meet together at a common energy scale if we run the renormalization group using the Standard Model. With the addition of SUSY, the match is within the ability that theory is able to predict the values.
Supersymmetric quantum mechanics
- Main article: supersymmetric quantum mechanics
Supersymmetric quantum mechanics adds the SUSY superalgebra to quantum mechanics as opposed to quantum field theory. In Theoretical physics, supersymmetric quantum mechanics is an area of research where mathematical concepts from High-energy physics are applied to the seemingly more Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons In quantum field theory (QFT the forces between particles are mediated by other particles Supersymmetric quantum mechanics often comes up when studying the dynamics of supersymmetric solitons and due to the simplified nature of having fields only functions of time (rather than space-time), a great deal of progress has been made in this subject and is now studied in its own right. In Mathematics and Physics, a soliton is a self-reinforcing solitary wave (a wave packet or pulse that maintains its shape while it travels at constant speed
SUSY quantum mechanics involves pairs of Hamiltonians which share a particular mathematical relationship, which are called partner Hamiltonians. In Quantum mechanics, the Hamiltonian H is the Observable corresponding to the Total energy of the system (The potential energy terms which occur in the Hamiltonians are then called partner potentials. Potential energy can be thought of as Energy stored within a physical system ) An introductory theorem shows that for every eigenstate of one Hamiltonian, its partner Hamiltonian has a corresponding eigenstate with the same energy. In Mathematics, given a Linear transformation, an of that linear transformation is a nonzero vector which when that transformation is applied to it changes This fact can be exploited to deduce many properties of the eigenstate spectrum. It is analogous to the original description of SUSY, which referred to bosons and fermions. We can imagine a "bosonic Hamiltonian", whose eigenstates are the various bosons of our theory. The SUSY partner of this Hamiltonian would be "fermionic", and its eigenstates would be the theory's fermions. Each boson would have a fermionic partner of equal energy.
SUSY concepts have provided useful extensions to the WKB approximation. In Physics, the WKB (Wentzel–Kramers–Brillouin approximation also known as WKBJ (Wentzel–Kramers–Brillouin–Jeffreys approximation is the most familiar In addition, SUSY has been applied to non-quantum statistical mechanics through the Fokker-Planck equation. Statistical mechanics is the application of Probability theory, which includes mathematical tools for dealing with large populations to the field of Mechanics The Fokker–Planck equation describes the Time evolution of the Probability density function of the position of a particle and can be generalized to other observables
See supersymmetric quantum mechanics for a more detailed discussion. In Theoretical physics, supersymmetric quantum mechanics is an area of research where mathematical concepts from High-energy physics are applied to the seemingly more
Mathematics
SUSY is also sometimes studied mathematically for its intrinsic properties. This is because it describes complex fields satisfying a property known as holomorphy, which allows holomorphic quantities to be exactly computed. Holomorphic functions are the central object of study of Complex analysis; they are functions defined on an open subset of the complex number plane This makes supersymmetric models useful toy models of more realistic theories. In Physics, a toy model is a simplified set of objects and equations relating them that can nevertheless be used to understand a mechanism that is also useful in the full non-simplified A prime example of this has been the demonstration of S-duality in four dimensional gauge theories that interchanges particles and monopoles.
General Supersymmetry
Supersymmetry appears in many different contexts in theoretical physics that are closely related. It is possible to have multiple supersymmetries and also have supersymmetric extra dimensions.
Extended Supersymmetry
- Main article: extended supersymmetry
It is possible to have more than one kind of supersymmetry transformation. In Theoretical physics, extended supersymmetry is Supersymmetry whose infinitesimal generators Q_i^\alpha carry not only a Spinor Theories with more than one supersymmetry transformation are known as extended supersymmetric theories. In Theoretical physics, extended supersymmetry is Supersymmetry whose infinitesimal generators Q_i^\alpha carry not only a Spinor The more supersymmetry a theory has, the more constrained the field content and interactions are. Typically the number of copies of a supersymmetry is a power of 2, i. e. 1, 2, 4, 8. In four dimensions, a spinor has four degrees of freedom and thus the minimal number of supersymmetry generators is four in four dimensions and having eight copies of supersymmetry means that there are 32 supersymmetry generators.
The maximal number of supersymmetry generators possible is 32. Theories with more than 32 supersymmetry generators automatically have massless fields with spin greater than 2. It is not known how to make massless fields with spin greater than two interact, so the maximal number of supersymmetry generators considered is 32. This corresponds to an N=8 supersymmetry theory. Theories with 32 supersymmetries automatically have a graviton.
In four dimensions there are the following theories
- N=1 with Chiral, Vector, and Gravity multiplets
- N=2 with Hyper, Vector and Gravity multiplets
- N=4 with Vector and Gravity multiplets
- N=8 with only a Gravity multiplet
Supersymmetry in Alternate Numbers of Dimensions
It is possible to have supersymmetry in alternate dimensions. Because the properties of spinors change drastically between different dimensions, each dimension has its characteristic. In d dimensions, the size of spinors is roughly 2d / 2 or 2(d − 1) / 2. Since the maximum number of supersymmetries is 32, the greatest number of dimensions in which a supersymmetric theory can exist is eleven.
Supersymmetry as a quantum group
Main article: Supersymmetry as a quantum group
Supersymmetry can be reinterpreted in the language of noncommutative geometry and quantum groups. The concept in Theoretical physics of Supersymmetry can be reinterpretated in the language of Noncommutative geometry and Quantum groups In particular Noncommutative geometry, or NCG, is a branch of Mathematics concerned with the possible spatial interpretations of Algebraic structures for which the In Mathematics and Theoretical physics, quantum groups are certain Noncommutative algebras that first appeared in the theory of Quantum integrable systems In particular, it involves a mild form of noncommutativity, namely supercommutativity. In Mathematics, a supercommutative algebra is a Superalgebra (i See the main article for more details.
Supersymmetry in quantum gravity
Supersymmetry is part of a larger enterprise of theoretical physics to unify everything we know about the physical world into a single fundamental framework of physical laws, known as the quest for a Theory of Everything (TOE). A theory of everything ( TOE) is a putative Theory of Theoretical physics that fully explains and links together all known physical phenomena A significant part of this larger enterprise is the quest for a theory of quantum gravity, which would unify the classical theory of general relativity and the Standard Model, which explains the other three basic forces in physics (electromagnetism, the strong interaction, and the weak interaction), and provides a palette of fundamental particles upon which all four forces act. Quantum gravity is the field of Theoretical physics attempting to unify Quantum mechanics, which describes three of the fundamental forces of nature General relativity or the general theory of relativity is the geometric theory of Gravitation published by Albert Einstein in 1916 The Standard Model of Particle physics is a theory that describes three of the four known Fundamental interactions together with the Elementary particles In Physics, a fundamental interaction or fundamental force is a mechanism by which particles interact with each other and which cannot be explained in terms Electromagnetism is the Physics of the Electromagnetic field: a field which exerts a Force on particles that possess the property of In particle physics the strong interaction, or strong force, or color force, holds Quarks and Gluons together to form Protons and The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four Fundamental interactions of nature In Particle physics, an elementary particle or fundamental particle is a particle not known to have substructure that is it is not known to be made Two of the most active approaches to forming a theory of quantum gravity are string theory and loop quantum gravity (LQG), although in theory, supersymmetry could be a component of other theoretical approaches as well. String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings Loop quantum gravity (LQG, also known as loop gravity and Quantum geometry, is a proposed quantum theory of Spacetime which attempts to reconcile the theories
For string theory to be consistent, supersymmetry appears to be required at some level (although it may be a strongly broken symmetry). String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings In particle theory, supersymmetry is recognized as a way to stabilize the hierarchy between the unification scale and the electroweak scale (or the Higgs boson mass), and can also provide a natural dark matter candidate. In Theoretical physics, a hierarchy problem occurs when the fundamental parameters ( couplings or masses of some Lagrangian are vastly different (usually The Higgs Boson is a hypothetical massive scalar Elementary particle predicted to exist by the Standard Model of Particle physics In Physics and cosmology, dark matter is hypothetical Matter that does not interact with the electromagnetic force but whose presence can be inferred from String theory also requires extra spatial dimensions which have to be compactified as in Kaluza-Klein theory. In Physics, Kaluza–Klein theory (or KK theory, for short is a model that seeks to unify the two fundamental forces of Gravitation and
Loop quantum gravity (LQG), in its current formulation, predicts no additional spatial dimensions, nor anything else about particle physics. Loop quantum gravity (LQG, also known as loop gravity and Quantum geometry, is a proposed quantum theory of Spacetime which attempts to reconcile the theories These theories can be formulated in three spatial dimensions and one dimension of time, although in some LQG theories dimensionality is an emergent property of the theory, rather than a fundamental assumption of the theory. For other uses see Emergence (disambiguation, Emergent, and Emergency. Also, LQG is a theory of quantum gravity which does not require supersymmetry. Lee Smolin, one of the originators of LQG, has proposed that a loop quantum gravity theory incorporating either supersymmetry or extra dimensions, or both, be called "loop quantum gravity II". Lee Smolin (born 1955 in New York City) is an American Theoretical physicist, a researcher at the Perimeter Institute for Theoretical Physics
If experimental evidence confirms supersymmetry in the form of supersymmetric particles such as the neutralino that is often believed to be the lightest superpartner, some people believe this would be a major boost to string theory. In Particle physics, a superpartner is a particle related to a more standard particle by Supersymmetry. In Particle physics, the neutralino is a hypothetical particle part of the doubling of the menagerie of particles predicted by supersymmetric theories In Particle physics, a superpartner is a particle related to a more standard particle by Supersymmetry. String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings Since supersymmetry is a required component of string theory, any discovered supersymmetry would be consistent with string theory. If the Large Hadron Collider and other major particle physics experiments fail to detect supersymmetric partners or evidence of extra dimensions, many versions of string theory which had predicted certain low mass superpartners to existing particles may need to be significantly revised. String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings The failure of experiments to discover either supersymmetric partners or extra spatial dimensions, as of 2008, has encouraged loop quantum gravity researchers. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common Loop quantum gravity (LQG, also known as loop gravity and Quantum geometry, is a proposed quantum theory of Spacetime which attempts to reconcile the theories
History of supersymmetry
In the early 1970s Yu. A. Golfand and E. P. Likhtman in Moscow (in 1971), D. V. Volkov and V. P. Akulov in Kharkov (in 1972) and J. Wess and B. Zumino in USA (in 1974) independently discovered supersymmetry, a radically new type of symmetry of space-time and fundamental fields. Bruno Zumino is an Italian Theoretical physicist and emeritus faculty at the University of California Berkeley. It has allowed one to establish a relationship between elementary particles of different quantum nature, bosons and fermions, and to non-trivially unify space-time and internal symmetries of the microscopic World. Supersymmetry first arose in the context of an early version of string theory by Ramond, John H. Schwarz and Andre Neveu, but the mathematical structure of supersymmetry has subsequently been applied successfully to other areas of physics; firstly by Wess, Zumino, and Abdus Salam and their fellow researchers to particle physics, and later to a variety of fields, ranging from quantum mechanics to statistical physics. String theory is a still-developing scientific approach to Theoretical physics, whose original building blocks are one-dimensional extended objects called strings Ramond is a surname and may refer to Louis Ramond de Carbonnières (1755–1827 French politician geologist and botanist John Henry Schwarz (born 1941) is an American theoretical physicist. André Neveu (born 1946 is a French Physicist working on String theory and Quantum field theory who coinvented the Neveu-Schwarz algebra Abdus Salam ( Urdu: محمد عبد السلام) ( January 29, 1926; Jhang Punjab &ndash November 21, Quantum mechanics is the study of mechanical systems whose dimensions are close to the Atomic scale such as Molecules Atoms Electrons Statistical mechanics is the application of Probability theory, which includes mathematical tools for dealing with large populations to the field of Mechanics It remains a vital part of many proposed theories of physics.
The first realistic supersymmetric version of the Standard Model was proposed in 1981 by Howard Georgi and Savas Dimopoulos and is called the Minimal Supersymmetric Standard Model or MSSM for short. Howard Mason Georgi III, born in 1947 in San Bernardino California, is Harvard College Professor and Mallinckrodt Professor of Physics at Harvard Savas Dimopoulos (born 1952 is a Greek Particle physicist at Stanford University. The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist It was proposed to solve the hierarchy problem and predicts superpartners with masses between 100 GeV and 1 TeV. In Theoretical physics, a hierarchy problem occurs when the fundamental parameters ( couplings or masses of some Lagrangian are vastly different (usually As of 2008 there is no irrefutable experimental evidence that supersymmetry is a symmetry of nature. In 2008 the Large Hadron Collider at CERN is scheduled to produce the world's highest energy collisions and offers the best chance at discovering superparticles for the foreseeable future. The European Organization for Nuclear Research (Organisation Européenne pour la Recherche Nucléaire known as CERN
See also
References
- A Supersymmetry Primer by S. In Particle physics, a superpartner is a particle related to a more standard particle by Supersymmetry. The Minimal Supersymmetric Standard Model (MSSM is the minimal extension to the Standard Model that realizes Supersymmetry, although non-minimal extensions do exist In Mathematics, a Lie superalgebra is a generalisation of a Lie algebra to include a Z 2- grading. In Mathematics and Theoretical physics, quantum groups are certain Noncommutative algebras that first appeared in the theory of Quantum integrable systems In the mathematical field of Representation theory, a representation of a Lie superalgebra is an action of Lie superalgebra L on a The concept of supergroup is a Generalization of that of group. " Superspace " has had two meanings in physics The word was first used by John Wheeler to describe the Configuration space of General relativity; for example In Particle physics, supersymmetry (often abbreviated SUSY) is a Symmetry that relates elementary particles of one spin to another particle that In Theoretical physics, a supercharge is a generator of Supersymmetry transformations Martin, 1999
- Introduction to Supersymmetry By Joseph D. Lykken, 1996
- An Introduction to Supersymmetry By Manuel Drees, 1996
- Introduction to Supersymmetry By Adel Bilal, 2001
- An Introduction to Global Supersymmetry by Philip Arygres, 2001
- Weak Scale Supersymmetry by Howard Baer and Xerxes Tata, 2006. Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar.
- Cooper, F. , A. Khare and U. Sukhatme. "Supersymmetry in Quantum Mechanics. " Phys. Rep. 251 (1995) 267-85 (arXiv:hep-th/9405029).
- Junker, G. Supersymmetric Methods in Quantum and Statistical Physics, Springer-Verlag (1996).
- Kane, G. L. and Shifman, M. , eds. The Supersymmetric World: The Beginnings of the Theory, World Scientific, Singapore (2000). ISBN 981-02-4522-X.
- D. V. Volkov, V. P. Akulov, Pisma Zh. Eksp. Teor. Fiz. 16 (1972) 621; Phys. Lett. B46 (1973) 109.
- V. P. Akulov, D. V. Volkov, Teor. Mat. Fiz. 18 (1974) 39.
- Weinberg, Steven, The Quantum Theory of Fields, Volume 3: Supersymmetry, Cambridge University Press, Cambridge, (1999). ISBN 0-521-66000-9.
- Wess, Julius, and Jonathan Bagger, Supersymmetry and Supergravity, Princeton University Press, Princeton, (1992). ISBN 0-691-02530-4.
- Bennett GW, et al; Muon (g−2) Collaboration (2004). "Measurement of the negative muon anomalous magnetic moment to 0. 7 ppm". Physical Review Letters 92 (16): 161802. doi:. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. PMID 15169217.
- Brookhaven National Laboratory (Jan. 8, 2004). New g−2 measurement deviates further from Standard Model. Press Release.
- Fermi National Accelerator Laboratory (Sept 25, 2006). Fermilab's CDF scientists have discovered the quick-change behavior of the B-sub-s meson. Press Release.
External links
- "Particle wobble shakes up supersymmetry", Cosmos magazine, September 2006
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