A postulated symmetry between bosonic and fermionic fields in quantum field theories and string theories.

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84 views

Basic question about superspace, Grassmann numbers and world sheet supersymmetry

So, I'm trying to read the section on superspace from the book on string theory by Becker, Becker and Schwarz, and I realized that I've been stuck on something simple for a while. Some relevant ...
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19 views

SUSY without gaugino [on hold]

In Minimal Supersymmetric Standard Model (MSSM) with $R$-parity, gauginos have Majorana mass. If we use $R$-symmetry instead of $R$-parity, gauginos do not have Majorana mass. But they can acquire ...
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26 views

Supersymmetries of the type IIB D3-brane action

The following query is based on a reading of section 2.2 of a paper by Graña and Polchinski. The idea is to begin with the D3 brane action of the form $$ ds^2 = Z^{-1/2}\eta_{\mu\nu}dx^\mu dx^\nu + ...
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50 views
+50

A question about genus one string amplitude

In BCOV's paper http://arxiv.org/abs/hep-th/9309140 the genus one string amplitude of a Calabi-Yau 3-fold was explained in the B-model as the Ray-Singer torsion (there is a similar discussion in the ...
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1answer
27 views

Superstring vacuum amplitude on the torus

My question is how to obtain the superstring (Type II A and B) vacuum amplitudes on a torus. They are given in Polchinski's String Theory Vol. 2 equation (10.7.9): ...
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49 views

Kähler Potential of Calabi-Yau volume

At tree level, the Kähler potential is given by (neglecting complex structure) $K = -\ln(-\mathrm{i}(\tau - \bar{\tau})) - 2\ln(V_{CY})$ where $V_{CY} = \frac{1}{6} \kappa_{abc}t^at^bt^c$ ia the the ...
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41 views

advantages and disadvantages of using topological quantum computation to study grand-unified SO(10) supersymmetric standard model

What are some references for advantages and disadvantages of using topological quantum computation to study grand-unified SO(10) supersymmetric standard model with respect to other grand unification ...
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1answer
63 views

Is time reversal symmetry broken in (conventional) superconductors?

How can one see it from BCS wavefunction and BCS Hamiltonian? i.e. $$H_{BCS}=\sum_{k\sigma}\epsilon_k c_{k\sigma}^\dagger c_{k\sigma}-\Delta^*\sum_k c_{k\uparrow}^\dagger ...
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24 views

Elliptic genus; What is it within string/M-theory?

What is the elliptic genus (see also Witten index) in string/M-theory and (susy gauge)field theory constructions out of them? What does it tell us heuristically and what is its relation to the ...
4
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0answers
36 views

Will the new LHC data falsify some theories? [closed]

There are plenty of extensions of the Standard Model, that all agree until the energy scales that have already been explored, but will differ at the new energy range of 14 TeV. This means the data ...
7
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55 views

Was there a period of doubt in the history of the Higgs mechanism? [migrated]

As the LHC begins its second run this year, the physics community seems to be significantly split between those who are confident that SUSY exists and those who believe it doesn't, given its failure ...
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31 views

Meaning of the Coulomb and Higgs branch for non-Lagrangian theories?

What is the meaning of the Coulomb and Higgs branch for non-Lagrangian theories like the $T_N$ theories that arise as 5-brane webs and correspond to CY 3-folds in M-theory? This is related to an older ...
4
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2answers
105 views

Viability of a Fayet Iliopoulos term in the MSSM

Why is a Fayet-Iliopoulos term $-kD$ irrelevant or subdominant in the in the MSSM (Minimal Susy Standard Model)? According to Martin (A Supersymmetry Primer, p.70) it's because squarks and sleptons ...
2
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0answers
50 views

Questions about the existence of 5d & 6d version of 4d ${\cal N}=2$ SCFTs

Given a 4d N=2 Superconfomal field theory (SCFT) with a global flavor symmetry ( $\mathfrak{f}$ as the corresponding lie algebra), can we clam that this theory can always flow from a 5d ${\cal N}=1$ ...
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0answers
13 views

Symbolic algebra to obtain equations of motion from supergravity actions [duplicate]

While trying to study the classical supergravity solutions, I realized that there's a considerable amount of intermediate tensor algebra involved, and while it is imperative that I work out all the ...
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0answers
27 views
1
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1answer
36 views

Why is the torus important for compactification in string theory? (aka much ado about the torus)

Why is the torus important in string theory and supergravity? To be specific, why does one care about something like compactification of Type IIB or IIA supergravity on a torus $T^5$, as opposed to ...
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32 views

Notation - d.o.f.'s for Grassmann delta functions in a SUSY field theory amplitude

I was reading the following paper http://arxiv.org/pdf/1306.2962v1.pdf as I stumbled upon an issue concerning counting and assigning the Grassmann degrees of freedom that appear in grassmann delta ...
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29 views

The low dimensional end of the brane scan

Common wisdom says that only the top dimensional part of the brane scan of Green-Schwarz super p-brane sigma models is quantum consistent (the critical strings and the M-branes). But by the results in ...
2
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1answer
37 views

Why does dimensional reduction of 10,6,2 to 9,5,1 have an equal number of supersymmetry?

In general, the number of supersymmetry is different for each dimension since from dimensional reduction, the number of supersymmetry is usually increased. $i.e$ 4d N=1 $\rightarrow$ 3d N=2 ...
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0answers
30 views

supersymmetry in 7, 8, 9 dimension

Why above dimension (7,8,9) the number of supercharge per supersymmetry is equal? $i.e$ For 32 supercharges, supersymmetry in 7,8,9 dimension is describe by $N=2$. And for 16 supercharges, ...
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22 views

supersymmetry in 2,6,10 dimension

Why the susy has chirality in above (2,6,10) dimension? What i am saying is that for $2, 6, 10$ dimension we can write as follows For 2d : $N=(16,16), \cdots N=(2,2), N=(2,0), N=(1,1), N=(1,0)$ are ...
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1answer
36 views

Why do we restrict the maximal supercharge to 32?

Many supersymmetry textbook state that the maximal supersymmetry in any dimension has 32 hermitian supercharges. (Actually for lowest number of supersymmetry $N=1$ the highest dimension is $D=11$) I ...
3
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1answer
67 views

Type IIB string theory is chiral. Do there exist non-chiral II SUGRA theories?

Type IIB string theory is chiral. Do there exist non-chiral $\mathcal{N}=2$ II SUGRA theories? The answer is apparently yes. Additionally how do we understand the fact that Type IIB SUGRA is chiral ...
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0answers
19 views

How do we use the Killing spinors to determine the resulting supersymmetry conserved?

How do we exactly use the Killing spinors to determine the resulting supersymmetry conserved? Is there some nice "toy" example you could provide me with to see this and convince my self? And is there ...
5
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70 views

Intuition for S-duality

first of all, I need to confess my ignorance with respect to any physics since I'm a mathematician. I'm interested in the physical intuition of the Langlands program, therefore I need to understand ...
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72 views

Intuition for Homological Mirror Symmetry

first of all, I need to confess my ignorance with respect to any physics since I'm a mathematician. I'm interested in the physical intuition of the Langlands program, therefore I need to understand ...
0
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1answer
61 views

Why 5D gauge theory is non-renormalizable?

My question is following "Why 5D gauge theory is non-renormalizable?" Here I treat $5D$ supersymmetric gauge theories. Also I heard Non-renormalizablity of $5D$ gauge theories implies the ...
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0answers
31 views

SUSY preserved by an extended D-brane

There's a nice way to prove that for an extended D-brane half of SUSY is preserved, from perturbative string argument with SUSY Ward identities and the doubling trick (at least, at tree-level and ...
3
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0answers
31 views

What information do quiver gauge diagrams provide?

I am struggling to understand what the information one can extract by looking a quiver diagram for a quiver gauge theory is. I understand what quivers are but I cannot get some physical intuition and ...
0
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1answer
45 views

Reference request for supersymmetric localization

I would like to ask for some readable introduction or maybe review of the technique of supersymmetric localization for $\mathcal{N}=1,2$ SUSY theories. I would like a different one than the one people ...
2
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0answers
43 views

Running of the Higgs mu term (or: running of individual mass terms in a complicated mass matrix)

I am wondering how to calculate the (one-loop) beta function for an individual mass term that appears in combination with a number of other mass terms in the coefficients of a number of fields. What ...
2
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0answers
67 views

What exactly does it mean to wrap a D-brane or a M-brane in a Riemann surface $\Sigma_g$?

What exactly does it mean to wrap a D-brane or an M-brane in a Riemann surface $\Sigma_g$ ($g$ is the genous)? Is there some mathematical statement? And why do we get various supersymmetric gauge ...
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1answer
38 views

What exactly are the ADE type of gauge theories?

What exactly are the ADE type of (susy) gauge theories? What exactly we mean, intuitively, the ADE singularities? What are their relation to brane constructions and do you have any references one ...
2
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0answers
28 views

Resource commendations for SUSY gauge theory [duplicate]

Does anyone know of recent SUSY gauge theory reviews aimed at the graduate student? Preferably something to bring the reader up to speed?
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43 views

Lorentz violation in String theory

First of all, why are there so many researches to find Lorentz violation? Are there some models of (super-)string theory that include Lorentz violation at some scale?
2
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1answer
51 views

Extended SuSy from the kappa-Symmetry WZW terms

In José de Azcárraga, Jerome Gauntlett, J.M. Izquierdo, Paul Townsend, Topological Extensions of the Supersymmetry Algebra for Extended Objects, Phys.Rev.Lett. 63 (1989) 2443 (spire) it was ...
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votes
2answers
143 views

Wess-Zumino Gauge in non-Abelian supersymmetric theory

I've got a question concerning non-Abelian supersymmetric gauge theories. Consider supersymmetric non-Abelian theory realized on chiral superfields $\Phi_i$ in a representation $R$ with matrix ...
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1answer
41 views

What does “local composite symmetry” mean in ${\cal N}=8$ $d=5$ supergravity?

What does it mean "local composite symmetry" in supergravity? Specifically, I don't understand very well the local composite symmetry ${\rm USp}(8)$ in ${\cal N}=8$ $d=5$ supergravity.
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1answer
27 views

Mixing Higgses and sneutrinos

I have a question which might have a trivial answer, but since I am not sure about it I'll ask it anyway. When working in supersymmetric models, one usually has at least 2 Higgs doublets. Assuming CP ...
2
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0answers
41 views

Quivers Representations in SUSY gauge theories

I would like to hear some reasons and ideas on how quivers are useful in SUSY gauge theories. There is a nice answer about the case of D-branes here but it is not clear on their appearance in gauge ...
2
votes
0answers
55 views

What is the difference between the groups $PSU(N)$ and $SU(N)$? [closed]

What is the difference between the groups $PSU(N)$ and $SU(N)$? For example how is $PSU(2,2|4)$ different than $SU(2,2|4)$?
2
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2answers
101 views

Why does the Bohr-Sommerfeld quantization for give the exact energy-levels for a harmonic oscillator?

Why does the Bohr-Sommerfeld rule for quantization give the exact energy-levels for a simple harmonic oscillator?
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0answers
116 views

Questions regarding $D=4 $ ${\cal N}=4$ supersymmetric Yang-Mills

I have some questions regarding the $D=4 $ ${\cal N}=4$ super-Yang-Mills theory (the one with a really long action which can be acquired by compactifying the 10-dimensional ${\cal N}=1$ theory). I ...
3
votes
0answers
35 views

Trilinear term in SUSY soft-breaking

In MSSM soft-SUSY breaking, there are such term called 'A-triliear term'. But, some papers, e.g Riva-Biggio-Pomarol, do not have trilinear term. What is the use of introducing trilinear term?
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0answers
24 views

Vev of Energy momentum tensor and $\beta-$ function in a supersymmetric QFT

We know that if a gauge theory runs then the vev of the (trace of) energy momentum tensor is proportional to (possibly sum of) beta function of the gauge couplings. In a supersymmetric gauge theory ...
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18 views

which data and experiment prove mirror symmetry

refer from the book by David A Cox, Mirror Symmetry and Algebraic Geometry how to demonstrate supersymmetry eliminate the difficulties of string theories how to use data to show eigenspace (p,q) = ...
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1answer
89 views

What is the motivation behind the GSO projection in superstring theory?

I do agree that the GSO "works", making the number of degrees of freedom match on the bosonic and fermionic side and that it sweeps away the problematic tachyon. However it is very artificial, it ...
2
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0answers
36 views

How well theoretically motivated is $R$-parity?

I understand that $R$-parity is empirically necessary in order to avoid proton decay, but theoretically I'm worried that it amounts to a tune or "hack" that spoils the naturalness argument for ...
4
votes
1answer
75 views

What does the discovery of the Higgs boson mean for SUSY?

I've seen many differing opinions on how the discovery of the Higgs boson (specifically due to its mass) has effected theories of Super Symmetry, but all seem fairly biased. I'm wondering if someone ...