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For the episode of the American TV series Angel, see Supersymmetry (Angel).

Supersymmetry (SUSY), a theory of particle physics, is a proposed type of spacetime symmetry that relates two basic classes of elementary particles: bosons, which have an integer-valued "spin", and fermions, which have a half-integer spin.[1] Each particle from one group is associated with a particle from the other, known as its superpartner, the spin of which differs by a half-integer. In a theory with perfectly "unbroken" supersymmetry, each pair of superpartners shares the same mass and internal quantum numbers besides spin – for example, a "selectron" (superpartner electron) would be a boson version of the electron, and would have the same mass energy and thus be equally easy to find in a laboratory. However, since no superpartners have been observed yet, if supersymmetry exists then it must be a spontaneously broken symmetry.[2][3] If supersymmetry is a true symmetry of nature, it would explain many mysterious features of particle physics and would help solve paradoxes such as the cosmological constant problem. The Minimal Supersymmetric Standard Model is one of the best studied candidates for physics beyond the Standard Model.

There is only indirect evidence for the existence of supersymmetry, primarily in the form of evidence for gauge coupling unification.[4] Direct confirmation would entail production of superpartners at collider experiments, such as at the Large Hadron Collider. Results from the first run of the LHC are consistent with the Standard Model, and thus have set limits on supersymmetric models, leading some physicists to support exploring other ideas.[5] A second run of the LHC will resume looking for supersymmetry, and other new physics, at higher energies beginning in 2015.


A supersymmetry relating mesons and baryons was first proposed, in the context of hadronic physics, by Hironari Miyazawa during 1966. This supersymmetry did not involve spacetime, that is it concerned internal symmetry, and was broken badly. His work was largely ignored at the time.[6][7][8][9]

J. L. Gervais and B. Sakita (during 1971),[10] Yu. A. Golfand and E. P. Likhtman (also during 1971), and D.V. Volkov and V.P. Akulov (1972),[11] independently rediscovered supersymmetry in the context of quantum field theory, a radically new type of symmetry of spacetime and fundamental fields, which establishes a relationship between elementary particles of different quantum nature, bosons and fermions, and unifies spacetime and internal symmetries of microscopic phenomena. Supersymmetry with a consistent Lie-algebraic graded structure on which the Gervais−Sakita rediscovery was based directly first arose during 1971[12] in the context of an early version of string theory by Pierre Ramond, John H. Schwarz and André Neveu.

Finally, Julius Wess and Bruno Zumino (during 1974)[13] identified the characteristic renormalization features of four-dimensional supersymmetric field theories, which identified them as remarkable QFTs, and they and Abdus Salam and their fellow researchers introduced early particle physics applications. The mathematical structure of supersymmetry (Graded Lie superalgebras) has subsequently been applied successfully to other topics of physics, ranging from nuclear physics,[14][15] critical phenomena,[16] quantum mechanics to statistical physics. It remains a vital part of many proposed theories of physics.

The first realistic supersymmetric version of the Standard Model was proposed during 1977 by Pierre Fayet and is known as the Minimal Supersymmetric Standard Model or MSSM for short. It was proposed to solve the hierarchy problem and predicts superpartners with masses between 100 GeV and 1 TeV.

The Large Hadron Collider at CERN is producing the world's highest-energy collisions and offers the best chance at discovering superparticles for the foreseeable future. After the discovery of the Higgs particle during 2012, it was expected that supersymmetric particles would be found at CERN, but there still has not been any evidence of them. The LHCb and CMS experiments at the LHC made the first definitive observation of a Strange B meson decaying into two muons, confirming a standard model prediction, but a disappointment for those hoping for signs of supersymmetry.[17] Neil Turok at Perimeter Institute concedes that theorists are disheartened at that situation, calling it a crisis. He described the LHC results as "simple, yet extremely puzzling" and said "we have to get people to try to find the new principles that will explain the simplicity".[18]


A major motivation for supersymmetry close to the tera-electronvolt (TeV) energy scale is the resolution of the hierarchy problem of the Standard Model. Without the extra supersymmetric particles, the Higgs boson mass is subject to quantum corrections which are so large as to drive it close naturally to the Planck mass barring its fine tuning to an extraordinarily tiny value. In the supersymmetric theory, however, these quantum corrections are canceled by those from the corresponding superpartners above the supersymmetry breaking scale, which becomes the new characteristic natural scale for the Higgs mass. Other attractive features of TeV-scale supersymmetry are the fact that it often provides a candidate dark matter particle at a mass scale consistent with thermal relic abundance calculations,[19][20] provides a natural mechanism for electroweak symmetry breaking[citation needed] and allows for the precise high-energy unification of the weak, the strong and electromagnetic interactions. Therefore, scenarios such that supersymmetric partners appear with masses not much greater than 1 TeV are considered the most well-motivated by theorists.[21] These scenarios would imply that experimental traces of the superpartners should have been detected from high-energy collisions in the LHC relatively soon; however to date this has not happened,[22][23] which is beginning to significantly constrain the most popular incarnations of supersymmetry. However, the total parameter space of consistent supersymmetric extensions of the Standard Model is extremely diverse and can not be ruled out definitively by the LHC.

Supersymmetry is also motivated by solutions to several theoretical problems, for generally providing many desirable mathematical properties, and for ensuring sensible behavior at high energies. Supersymmetric quantum field theory is often much easier to analyze, as many more problems become exactly solvable. When supersymmetry is imposed as a local symmetry, Einstein's theory of general relativity is included automatically, and the result is said to be a theory of supergravity. It is also a necessary feature of the most popular candidate for a theory of everything, superstring theory.

Another theoretically appealing property of supersymmetry is that it offers the only "loophole" to the Coleman–Mandula theorem, which prohibits spacetime and internal symmetries from being combined in any nontrivial way, for quantum field theories like the Standard Model with very general assumptions. The Haag-Lopuszanski-Sohnius theorem demonstrates that supersymmetry is the only way spacetime and internal symmetries can be combined consistently.[24]


Extension of possible symmetry groups[edit]

One reason that physicists explored supersymmetry is because it offers an extension to the more familiar symmetries of quantum field theory. 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 not any mass gap, the conformal group with a compact internal symmetry group. During 1971 Golfand and Likhtman were the first to show that the Poincaré algebra can be extended through introduction of four anticommuting spinor generators (in four dimensions), which later became known as supercharges. During 1975 the Haag-Lopuszanski-Sohnius theorem analyzed all possible superalgebras in the general form, including those with an extended number of the supergenerators and central charges. This extended super-Poincaré algebra paved the way for obtaining a very large and important class of supersymmetric field theories.

The supersymmetry algebra[edit]

Main article: Supersymmetry algebra

Traditional symmetries of physics are generated by objects that transform by the tensor representations of the Poincaré group and internal symmetries. Supersymmetries, however, are generated by objects that transform by the spinor representations. According to the spin-statistics theorem, bosonic fields commute while fermionic fields anticommute. Combining 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. Such an algebra is called a Lie superalgebra.

The simplest supersymmetric extension of the Poincaré algebra is the Super-Poincaré algebra. Expressed in terms of two Weyl spinors, has the following anti-commutation relation:

\{ Q_{ \alpha }, \bar{Q_{ \dot{ \beta }}} \} = 2( \sigma{}^{\mu} )_{ \alpha \dot{ \beta }} P_{\mu}

and all other anti-commutation relations between the Qs and commutation relations between the Qs and Ps vanish. In the above expression  P_{\mu} = -i \partial{}_{\mu} are the generators of translation and \sigma{}^{\mu} are the Pauli matrices.

There are representations of a Lie superalgebra that are analogous to representations of a Lie algebra. Each Lie algebra has an associated Lie group and a Lie superalgebra can sometimes be extended into representations of a Lie supergroup.

The Supersymmetric Standard Model[edit]

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. With the addition of 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) which can include the necessary additional new particles that are able to be superpartners of those in the Standard Model.

Cancellation of the Higgs boson quadratic mass renormalization between fermionic top quark loop and scalar stop squark tadpole Feynman diagrams in a supersymmetric extension of the Standard Model

One of the main motivations for SUSY comes from the quadratically divergent contributions to the Higgs mass squared. 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 greatest scale possible. This problem is known as the hierarchy problem. 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 weakly interacting massive particle (WIMP) dark matter candidate. The existence of a supersymmetric dark matter candidate is related closely to R-parity.

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. The supersymmetry break can not be done permanently by the particles of the MSSM as they currently appear. 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 permanently 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, arbitrary soft SUSY breaking terms are added to the theory which temporarily break SUSY explicitly but could never arise from a complete theory of supersymmetry breaking.

Gauge-coupling unification[edit]

One piece of evidence for supersymmetry existing is gauge coupling unification. The renormalization group evolution of the three gauge coupling constants of the Standard Model is somewhat sensitive to the present particle content of the theory. These coupling constants do not quite meet together at a common energy scale if we run the renormalization group using the Standard Model.[4] With the addition of minimal SUSY joint convergence of the coupling constants is projected at approximately 1016 GeV.[4]

Supersymmetric quantum mechanics[edit]

Supersymmetric quantum mechanics adds the SUSY superalgebra to quantum mechanics as opposed to quantum field theory. Supersymmetric quantum mechanics often becomes relevant when studying the dynamics of supersymmetric solitons, and due to the simplified nature of having fields which are only functions of time (rather than space-time), a great deal of progress has been made in this subject and it is now studied in its own right.

SUSY quantum mechanics involves pairs of Hamiltonians which share a particular mathematical relationship, which are called partner Hamiltonians. (The potential energy terms which occur in the Hamiltonians are then known as partner potentials.) An introductory theorem shows that for every eigenstate of one Hamiltonian, its partner Hamiltonian has a corresponding eigenstate with the same energy. 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.

Supersymmetry: Applications to condensed matter physics[edit]

SUSY concepts have provided useful extensions to the WKB approximation. Additionally, SUSY has been applied to disorder averaged systems both quantum and non-quantum (through statistical mechanics), the Fokker-Planck equation being an example of a non-quantum theory. The `supersymmetry' in all these systems arises from the fact that one is modelling one particle and as such the`statistics' don't matter. The use of the supersymmetry method provides a mathematical rigorous alternative to the replica trick, but only in non-interacting systems, which attempts to address the so-called `problem of the denominator' under disorder averaging. For more on the applications of supersymmetry in condensed matter physics see the book[25]

Supersymmetry in optics[edit]

Integrated optics was recently found[26] to provide a fertile ground on which certain ramifications of SUSY can be explored in readily-accessible laboratory settings. Making use of the analogous mathematical structure of the quantum-mechanical Schrödinger equation and the wave equation governing the evolution of light in one-dimensional settings, one may interpret the refractive index distribution of a structure as a potential landscape in which optical wave packets propagate. In this manner, a new class of functional optical structures with possible applications in phase matching, mode conversion[27] and space-division multiplexing becomes possible. SUSY transformations have been also proposed as a way to address inverse scattering problems in optics and as a one-dimensional transformation optics [28]


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. This makes supersymmetric models useful "toy models" of more realistic theories. A prime example of this has been the demonstration of S-duality in four-dimensional gauge theories[29] that interchanges particles and monopoles.

The proof of the Atiyah-Singer index theorem is much simplified by the use of supersymmetric quantum mechanics.[how?]

General supersymmetry[edit]

Supersymmetry appears in many related contexts of theoretical physics. It is possible to have multiple supersymmetries and also have supersymmetric extra dimensions.

Extended supersymmetry[edit]

It is possible to have more than one kind of supersymmetry transformation. Theories with more than one supersymmetry transformation are known as extended supersymmetric theories. The more supersymmetry a theory has, the more constrained are the field content and interactions. 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.

For four dimensions there are the following theories, with the corresponding multiplets[30](CPT adds a copy, whenever they are not invariant under such symmetry)

  • N = 1

Chiral multiplet: (0,12) Vector multiplet: (12,1) Gravitino multiplet: (1,32) Graviton multiplet: (32,2)

  • N = 2

hypermultiplet: (-12,02,12) vector multiplet: (0,122,1) supergravity multiplet: (1,322,2)

  • N = 4

Vector multiplet: (-1,-124,06,124,1) Supergravity multiplet: (0,124,16,324,2)

  • N = 8

Supergravity multiplet: (-2,-328,-128,-1256,070,1256,128,328,2)

Supersymmetry in alternate numbers of dimensions[edit]

It is possible to have supersymmetry in dimensions other than four. Because the properties of spinors change drastically between different dimensions, each dimension has its characteristic. In d dimensions, the size of spinors is approximately 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[edit]

Supersymmetry can be reinterpreted in the language of noncommutative geometry and quantum groups. In particular, it involves a mild form of noncommutativity, namely supercommutativity. See the main article for more details.

Supersymmetry in quantum gravity[edit]

Supersymmetry is part of a larger enterprise of theoretical physics to unify everything we know about the universe into a single consistent set of physical principles, known as the quest for a Theory of Everything (TOE). 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. Two of the most active methods of forming a theory of quantum gravity are string theory and loop quantum gravity (LQG), although in theory, supersymmetry could be a component of other theories as well.

For string theory to be consistent, supersymmetry seems to be required at some level (although it may be a strongly broken symmetry). 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. String theory also requires extra spatial dimensions which have to be compactified as in Kaluza–Klein theory.

Loop quantum gravity (LQG) predicts no additional spatial dimensions, nor anything else about particle physics. 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. 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".

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. 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. The failure of experiments to discover either supersymmetric partners or extra spatial dimensions, as of 2013, has encouraged loop quantum gravity researchers.


SUSY is not falsifiable, because its breaking mechanism and the minimum mass above which it is restored are unknown.[citation needed] This minimum mass can be pushed upwards to arbitrarily large values, without disproving the symmetry, and a non-falsifiable theory is generally considered unscientific. However, many theoretical physicists continue to emphasize supersymmetry because of its usefulness for quantum field theory, its interesting mathematical properties, and the possibility that extremely high energy physics (as in around the time of the big bang) are described by supersymmetric theories.

Current status[edit]

Supersymmetric models are constrained by a variety of experiments, including measurements of low-energy observables – for example, the anomalous magnetic moment of the muon at Brookhaven; the WMAP dark matter density measurement and direct detection experiments – for example, XENON-100; and by particle collider experiments, including B-physics, Higgs phenomenology and direct searches for superpartners (sparticles), at the Large Electron–Positron Collider, Tevatron and the LHC.

Historically, the tightest limits were from direct production at colliders. The first mass limits for squarks and gluinos were made at CERN by the UA1 experiment and the UA2 experiment at the Super Proton Synchrotron. LEP later set very strong limits.[31] In 2006 these limits were extended by the D0 experiment.[32][33]

From 2003, WMAP's dark matter density measurements have strongly constrained supersymmetry models, which have to be tuned to invoke a particular mechanism to sufficiently reduce the neutralino density.

Prior to the initiation of the LHC, during 2009, fits of available data to CMSSM and NUHM1 indicated that squarks and gluinos were most likely to have masses in the 500 to 800 GeV range, though values as high as 2.5 TeV were allowed with low probabilities. Neutralinos and sleptons were expected to be quite light, with the lightest neutralino and the lightest stau most likely to be found between 100 to 150 GeV.[34]

Lack of evidence[edit]

As of 2014, the LHC has not found evidence for supersymmetry, and, as a result, has surpassed existing experimental limits from the Large Electron–Positron Collider and Tevatron and partially excluded the aforementioned expected ranges.[35][36][37][38] Based on the data sample collected by the CMS detector at the LHC through the summer of 2011, CMSSM squarks have been excluded up to the mass of 1.1 TeV and gluinos have been excluded up to 500 GeV.[39] Searches are only applicable for a finite set of tested points because simulation using the Monte Carlo method must be made so that limits for that particular model can be calculated. This complicates matters because different experiments have looked at different sets of points. Some extrapolation between points can be made within particular models but it is difficult to set general limits even for the Minimal Supersymmetric Standard Model.

During 2011 and 2012, the LHC discovered a Higgs boson with a mass of about 125 GeV, and with couplings to fermions and bosons which are consistent with the Standard Model. The MSSM predicts that the mass of the lightest Higgs boson should not be much higher than the mass of the Z boson, and, in the absence of fine tuning (with the supersymmetry breaking scale on the order of 1 TeV), should not exceed 130 GeV. Furthermore, for values of the MSSM parameter tan β ≤ 3, it predicts a Higgs mass below 114 GeV over most of the parameter space.[40] This region of Higgs mass was excluded by LEP by 2000. The LHC result is somewhat problematic for the minimal supersymmetric model, as the value of 125 GeV is relatively large for the model and can only be achieved with large radiative loop corrections from top squarks, which many theorists consider to be "unnatural" (see naturalness and fine tuning).[41]

Arguments against[edit]

There are eight arguments against supersymmetry.

  • (1) The LUX experiment for cold dark matter has not observed neutralinos.
  • (2) The large size of the WMAP cold spot is larger than predicted by Lambda cold dark matter models.
  • (3) The large-scale flow of galaxies is larger than predicted by Lambda CDM models.
  • (4) The number of faint dwarf galaxies is smaller than predicted by Lambda CDM models.
  • (5) Neither the ATLAS nor the CMS collaboration have observed gluinos and squarks.
  • (6) The rest mass, interaction cross-section and decay rates of the Higgs boson are compatible with the standard theory, but not with earlier predictions by supersymmetric models.
  • (7) Dirac fermions can be described by a gravitation theory which includes Cartan torsion (Einstein-Cartan theory), supersymmetry is not required.
  • (8) The mass hierarchy problem of Grand Unified theories need not occur if Grand Unification does not exist. The proton decay predicted by Grand Unified theories has not been observed. The quantization of electric charge can be explained by theories which include Dirac magnetic monopoles, so Grand Unification is not necessary.[42]

The LHCb experiment at the Large Hadron Collider also observed an extremely rare particle decay event which casts doubt on many versions of supersymmetry.[43]

In spite of the null searches and the heavy Higgs, a recent analysis of the constrained minimal supersymmetric Standard Model, the CMSSM, suggests that the model is still compatible with all present experimental constraints.[44] The preferred masses for squarks and gluinos is about 2 TeV. The resulting fine-tuning of the Higgs boson mass and Z-boson mass (see mu problem and little hierarchy problem), however, is considered "unnatural", and some theorists now favor extended supersymmetry models – for example, the NMSSM.

See also[edit]


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  2. ^ Martin, Stephen P. (1997). "A Supersymmetry Primer". arXiv:hep-ph/9709356. 
  3. ^ Dine, Michael (2007). Supersymmetry and String Theory: Beyond the Standard Model. p. 169. 
  4. ^ a b c Gordon L. Kane, The Dawn of Physics Beyond the Standard Model, Scientific American, June 2003, page 60 and The frontiers of physics, special edition, Vol 15, #3, page 8 "Indirect evidence for supersymmetry comes from the extrapolation of interactions to high energies."
  5. ^ Wolchover, Natalie (November 20, 2012). "Supersymmetry Fails Test, Forcing Physics to Seek New Ideas". Quanta Magazine. 
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  7. ^ H. Miyazawa (1968). "Spinor Currents and Symmetries of Baryons and Mesons". Phys. Rev. 170 (5): 1586–1590. Bibcode:1968PhRv..170.1586M. doi:10.1103/PhysRev.170.1586. 
  8. ^ Michio Kaku, Quantum Field Theory, ISBN 0-19-509158-2, pg 663.
  9. ^ Peter Freund, Introduction to Supersymmetry, ISBN 0-521-35675-X, pages 26-27, 138.
  10. ^ Gervais, J. -L.; Sakita, B. (1971). "Field theory interpretation of supergauges in dual models". Nuclear Physics B 34 (2): 632. Bibcode:1971NuPhB..34..632G. doi:10.1016/0550-3213(71)90351-8. 
  11. ^ 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
  12. ^ Ramond, P. (1971). "Dual Theory for Free Fermions". Physical Review D 3 (10): 2415. Bibcode:1971PhRvD...3.2415R. doi:10.1103/PhysRevD.3.2415. 
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  14. ^ suggested here
  15. ^ Iachello, F. (1980). "Dynamical Supersymmetries in Nuclei". Physical Review Letters 44 (12): 772. Bibcode:1980PhRvL..44..772I. doi:10.1103/PhysRevLett.44.772. 
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  17. ^ CERN latest data shows no sign of supersymmetry – yet Phys.Org, 25 July 2013
  18. ^ Perimeter Institute and the crisis in modern physics Paul Wells, 5 Sep 2013
  19. ^ Jonathan Feng: Supersymmetric Dark Matter (pdf), University of California, Irvine, 11 May 2007
  20. ^ Torsten Bringmann: The WIMP "Miracle" (pdf) University of Hamburg
  21. ^
  22. ^ ATLAS SUSY search documents
  23. ^ CMS SUSY search documents
  24. ^ R. Haag, J. T. Lopuszanski and M. Sohnius, "All Possible Generators Of Supersymmetries Of The S Matrix", Nucl. Phys. B 88 (1975) 257
  25. ^ Supersymmetry in Disorder and Chaos, Konstantin Efetov, Cambridge university press, 1997.
  26. ^ Miri, M.-A.; Heinrich, M.; El-Ganainy, R.; Christodoulides, D. N. (2013). "Superymmetric optical structures". Physical Review Letters (APS) 110 (23): 233902. arXiv:1304.6646. Bibcode:2013PhRvL.110w3902M. doi:10.1103/PhysRevLett.110.233902. PMID 25167493. Retrieved April 2014. 
  27. ^ Heinrich, M.; Miri, M.-A.; Stützer, S.; El-Ganainy, R.; Nolte, S.; Szameit, A.; Christodoulides, D. N. (2014). "Superymmetric mode converters". Nature Communications (NPG) 5: 3698. arXiv:1401.5734. Bibcode:2014NatCo...5E3698H. doi:10.1038/ncomms4698. PMID 24739256. Retrieved April 2014. 
  28. ^ Miri, M.-A.; Heinrich, Matthias; Christodoulides, D. N. (2014). "SUSY-inspired one-dimensional transformation optics". Optica (OSA) 1 (2): 89. arXiv:1408.0832. doi:10.1364/OPTICA.1.000089. Retrieved August 2014. 
  29. ^ Krasnitz, Michael (2002). Correlation functions in supersymmetric gauge theories from supergravity fluctuafluctuations hHKtions (PDF). Princeton University Department of Physics: Princeton University Department of Physics. p. 91. 
  30. ^ Polchinski,J. String theory. Vol. 2: Superstring theory and beyond, Appendix B
  31. ^ LEPSUSYWG, ALEPH, DELPHI, L3 and OPAL experiments, charginos, large m0 LEPSUSYWG/01-03.1
  32. ^ The D0-Collaboration (2009). "Search for associated production of charginos and neutralinos in the trilepton final state using 2.3 fb−1 of data". arXiv:0901.0646. Bibcode:2009PhLB..680...34D. doi:10.1016/j.physletb.2009.08.011. 
  33. ^ The D0 Collaboration (2006). "Search for squarks and gluinos in events with jets and missing transverse energy using 2.1 fb-1 of pp¯ collision data at s=1.96 TeV". arXiv:0712.3805. Bibcode:2008PhLB..660..449D. doi:10.1016/j.physletb.2008.01.042. 
  34. ^ O. Buchmueller et al. (2009). "Likelihood Functions for Supersymmetric Observables in Frequentist Analyses of the CMSSM and NUHM1". The European Physical Journal C 64 (3): 391–415. arXiv:0907.5568. Bibcode:2009EPJC...64..391B. doi:10.1140/epjc/s10052-009-1159-z. 
  35. ^ Implications of Initial LHC Searches for Supersymmetry
  36. ^ Fine-tuning implications for complementary dark matter and LHC SUSY searches
  37. ^ What LHC tells about SUSY
  38. ^ Early SUSY searches at the LHC
  39. ^ CMS Collaboration; Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hammer, J.; Hänsel, S.; Hoch, M.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Krammer, M.; Liko, D.; Mikulec, I.; Pernicka, M.; Rahbaran, B.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A. et al. (November 2011). "Search for Supersymmetry at the LHC in Events with Jets and Missing Transverse Energy". Physical Review Letters 107 (22): 221804. arXiv:1109.2352. Bibcode:2011PhRvL.107v1804C. doi:10.1103/PhysRevLett.107.221804. PMID 22182023. 
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  42. ^ R. W. Kühne: Quantum Field Theory with Electric-Magnetic Duality and Spin-Mass Duality but Without Grand Unification and Supersymmetry. African Review of Physics 6 (2011) 165-179. [1] [2] [3]
  43. ^ M. Hogenboom (24 July 2013). "Ultra-rare decay confirmed in LHC". BBC. Retrieved 2013-08-18. 
  44. ^ [4]"Global Fits of the cMSSM and NUHM including the LHC Higgs discovery and new XENON100 constraints", C. Strege, G. Bertone, F. Feroz, M. Fornasa, R. Ruiz de Austri, R. Trotta, arXiv:1212.2636

Further reading[edit]

Theoretical introductions, free and online[edit]


On experiments[edit]

External links[edit]