The supersymmetry tag has no wiki summary.
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Auxiliary fields in supersymmetry
I know that auxiliary fields can be used to close the supersymmetry algebra in case the bosonic and fermionic on-shell degrees of freedom do not match. Could somebody please elaborate on this concept ...
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What constitutes a 'reliable' instanton calculation?
In Modern Supersymmetry, John Terning, on pgs 151, and 153 performs a so called 'reliable' instanton calculation when dealing with the ADS superpotential 'since the gauge group is completely broken'. ...
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How exactly do superstrings reduce the number of dimensions in bosonic string theory from 26 to 10 and remove the tachyons?
In bosonic string theory, to obtain the photon as the first excited state, the ground state must have a negative mass (tachyon). By applying $1 + 2 + 3 + \cdots = -1/12$, it can be shown (in a ...
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What are “hidden valley sectors”?
In this end of the year article, Prof. Strassler mentioned that hidden valley sectors could lead to some still open loopholes concerning the experimental discovery of supersymmetry and other BSM ...
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Linear combination of anomalous dimensions in effective potential on pseudomoduli space
In the paper of Intriligator, Seiberg, and Shih from 2007, they give an expression for the effective potential on the pseudo-moduli space $X$, estimated at large $X$ (equation 1.3).
In this equation, ...
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How to handle Yukawa contractions in calculating SUSY beta functions?
I'm reading Chapter 6 of Martin's introduction to SUSY http://arxiv.org/abs/hepph/9709356, which is about RGEs in the MSSM. I tried to convince myself of some of the calculations, and I was ...
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What is non-Abelian about non-Abelian Chern-Simons' theory?
One is aware that in the axial gauge (say the light-cone gauge $A_{-}=0$) non-supersymmetric Chern-Simons' theory is a quadratic theory. Hence in this gauge there are no gauge-gauge interactions. Then ...
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Conservation laws in mSUGRA model
Can somebody list all the quantum numbers (beside R-parity) that are conserved in vertex for SUSY particles in mSUGRA model?
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Witten's constrained S-matrix and Coleman-Mandula Theorem
I remember reading somewhere that Witten argued that if the Poincaré symmetry of spacetime were nontrivially combined with internal symmetries, then the S-matrix would be so constrained that the ...
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Can the mass of a SUSY particle depend on the process it participates in?
I believe that mass is property of every particle,as well as spin etc.Now I'm interested in SUSY particles in cMSSM model.Can it be,that mass of a SUSY particle (at one point in five parameter space) ...
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Low-scale supersymmetry
One of the major reasons SUSY was adopted in particle physics is to Naturally have a Higgs boson (a fundamental scalar) at the weak scale.
If we abandon this argument, what other motivation for ...
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why are two higgs doublets required in SUSY?
I can't really understand why two higgs doublets are required in SUSY.
From the literature, I have found opaque explanations that say something along the lines of: the superpotential W must be a ...
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It seems to me that superpotentials can be defined in a theory with or without supersymmetry. Is this true?
I recently read "An Introduction to Supersymmetry in Quantum Mechanical Systems" by T. Wellman (amongst other sources) in an effort to find out what a superpotential actually is and how it relates to ...
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123 views
Other Gross-Neveu like theories?
By "Gross-Neveu like" I mean non-supersymmetric QFTs whose partition function/beta-function (or any n-point function) is somehow exactly solvable in the large $N_c$ or $N_f$ or 't Hooft limit.
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SUSY, ways to boost Chargino/Neutralino production?
Does anybody know a good reference that works out the equations for the Chargino/Neutralino production cross section in SUSY? I'm trying to understand if there are any tricks for boosting the ...
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Dynamical supersymmetry breaking and Witten index
Witten index, defined as ${\rm Tr}(-1)^F$, makes know if supersymmetry is spontaneously broken or not for a given model. But it is known that supersymmetry can be also broken dynamically and one can ...
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Assuming SUSY is found to be incorrect, what would then be the most compelling candidates for dark matter?
From what I've read, the only remaining candidates appear to be either sterile neutrinos or MOND (MOdified Newtonian Dynamics -- it does seem to keep changing.)
Did I miss anything else plausible?
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Recent Higgs boson observation and credibility of superstring theories
Data are coming in, and it seems that recent Higgs boson observation is eliminating many SUSY models. If so, what is happening to superstring theories, like M-theory?
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A problem with supersymmetry transformation invariance
Consider the following transformation of the integration measure $dX d\psi_1 d\psi_2$:
where $\psi_1$ $\psi_2$,$\varepsilon^1$, and $\varepsilon^2$ are Grassman variables.
$\delta_\varepsilon X= ...
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Constructing Supersymmetric Lagrangians
It is a very trivial doubt but somehow I am not able to figure it out. While constructing a supersymmetric lagrangian we always even number of fermionic fields.
One reason is of course the product ...
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What interaction does a Fayet-Iliopoulos coupling parameterize the strength of?
Couplings give the strength of interactions. They appear in a Lagrangian as a coefficient to the two (or more) interacting fields. Unfortunately, I'm struggling to find a source that describes what it ...
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250 views
Feynman rules for SUSY
This might be an incredibly naive question, but I'm wondering if there are a set of rules for "translating" between Standard Model and SUSY. For instance, if I want want to go from a Standard Model ...
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What is the meaning of negative mass (in a SUSY spectrum)?
I was playing around with SuSpect to generate some SUSY mass spectrums and I'm often encountering situations where I get a negative neutralino mass.
What is the physical meaning of this negative ...
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What is the $\mu$ problem in SUSY?
I need a little bit of help in understanding the mu problem in SUSY. As I understand it, the gist of the problem is that $\mu$ must be on the same order of magnitude as the electroweak scale (246 ...
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Which SUSY models are affected by the recent LHCb result?
The LHCb has recently published the observation of $B_s \rightarrow \mu^+ \mu^-$ with a branching ratio that agrees with the Standard Model (SM). There are many blog posts about it (See: Of Particular ...
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alternatives to supersymmetry and Coleman-Mandule theorem
Humour me for a minute here and let's imagine that all interesting and plausible supersymmetry models have been "cornered" out by the experimental data;
what sort of alternatives are there for having ...
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What does the latest $B_s^0\rightarrow \mu^+\mu^-$ results mean for SUSY?
A paper from the LHCb collaboration just came out last week, stating basically that the $B_s^0\rightarrow\mu^+\mu^-$ decay matches standard model predictions, and people are already shouting that SUSY ...
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Does the Photino have mass or is it mass-less like the photon
Does the photino in super-symmetry have a mass, Or is this different in different super symmetric models?
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What do the supercharges in extended supersymmetry do?
What do the supercharges in extended supersymmetry do?
In $N=1$ supersymmetry there are a certain number of fermions and and equal number of bosons. You can transform all fermions to the bosons (and ...
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What is the hierarchy problem?
BACKGROUND
So far I understood that the hierarchy problem was the large difference between the gravitational scale, $M_{pl}\sim 10^{18}\; [GeV]$, compared with the electroweak scale, $M_{ew}\sim ...
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Relationship between hierarchy problem and higgs fine tuning?
I often hear of hierarchy problem being used synonymous with Higgs fine tuning (esp with regards with motivations for SUSY). What exactly is the relationship between the two problems? As I understand ...
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Why is the lightest Higgs not a free parameter in SUSY?
In the Standard Model, the Higgs mass doesn't really have any theoretical constraints. It could have basically any value and nothing 'breaks'.
However, in MSSM models, we often see the tree level ...
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Can auxiliary fields be thought of as Lagrange multipliers?
In the BRST formalism of gauge theories, the Lautrup-Nakanishi field $B^a(x)$ appears as an auxiliary variable
$$\mathcal{L}_\text{BRST}=-\frac{1}{4}F_{\mu\nu}^a F^{a\,\mu\nu}+\frac{1}{2}\xi B^a B^a + ...
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Missing transverse energy, exact definition
This might seem basic, but it is a bit confusing. You hear about missing transverse energy a lot in SUSY searches due to the LSP which cannot be detected.
Let's say I have the 4-vector for the LSP. ...
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dimensional analysis of Grassmann integration/differentiation
There is another paradox that I need to resolve:
The Berezin integration rules for Grassmann odd variables give the same result as differentiation:
If $f=x+\theta\psi$ is a superfunction, the ...
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How does a supersymmetry transformatio relates bosons to fermions?
A superfield is defined as a function of of a spacetime coordinate and two spinor coordinates, $\Phi (x, \theta, \theta^*)$. A supersymmetric transformation is then generated by the operator ...
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Limit on space-time dimension from susy
I read an argument saying that it would be impossible to write down a super-symmetric theory in more than 11 dimensions, this limit coming from the dimension of the Clifford algebra that goes as ...
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what is universality (with respect to SUSY and neutral kaon oscillations)?
I'm having trouble putting the pieces together. In SM, neutral kaon oscillation is heavily constrained. This means, roughly, that the squark mass matrices have to be diagonal. And this is called ...
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Boundary conditions in AdS/CFT
This question is in reference to this very famous paper of Witten.
In general through the whole paper why is the author able to just focus on the scalar field propagating in the bulk and not need ...
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Mathematical concept of supersymmetry
I wish to study supersymmetry in field theory(sometime in december). However, I am quite not sure what is needed for its study. In supersymmetry, I just want to get the mathematical idea, such as its ...
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The observation of a non-SM resonance at 38 MeV
Was reported here. Of course if this is real it is very exciting. It leads me to the question: given that it took so long to find this resonance at a meager 38 MeV, is it possible that all SUSY ...
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Interpretation of “superqubits”
Two very intriguing papers recently appeared on the arXiv, claiming that one can use "superqubits" -- a supersymmetric generalization of qubits -- to violate the Bell inequality by more than standard ...
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Some questions about flavour and R-symmetry in $2+1$ ${\cal N}=3$ theory
I have heard this fact that for ${\cal N}=3$ theories in $2+1$ with $N_f$ ${\cal N}=3$ matter fields the flavour symmetry group is $USp(N_f)$, $U(N_f)$ or $SO(2N_f)$ depending on whether the gauge ...
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Hypothetical very massive particles
I'm looking for a table or compilation of hypothetical very massive ($m\gtrsim 1$ TeV) particles and their expected masses (or bounds on them or relation with other scales). All I know is (please, ...
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R charge of the chiral multiplet in $2+1$ dimensions
These are two examples that I am puzzled by,
One can see in this paper on page 16 that for ${\cal N} =2$ theory on $2+1$ the R-charge of the $\phi$ and the $\psi$ is determined to be $\frac{1}{2}$ ...
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Wilson loops and gauge invariant operators (Part 1)
I guess the Hilbert space of the theory is precisely the space of all gauge invariant operators (mod equations of motion..as pointed out in the answers)
Is it possible that in a gauge theory the ...
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How convincing is the evidence for dark matter annihilation at 130 GeV in the galactic center from the Fermi Satellite data?
I listened to Christoph Weniger present his results at SLAC today. See his paper is here: http://arxiv.org/abs/1204.2797 and also see a different analysis here: http://arxiv.org/abs/1205.1045. The ...
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Superspace Uncertainty Principle
Do the "operator for translations in superspace" and the "position in superspace operator" follow an uncertainty principle? How "real" is superspace? Aside from being weird (and possibly just a ...
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Atomic structure and corresponding superpartner behavior
If all quantum particles have a superpartner, what happens, if this has been able to be speculated based on theory, to the superpartners when the corresponding partners start forming atoms?
Is there ...
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About 2+1 dimensional superconformal algebra
I would like to get some help in interpreting the main equation of the superconformal algebra (in $2+1$ dimenions) as stated in equation 3.27 on page 18 of this paper. I am familiar with supersymmetry ...
