Supersymmetry Definition and 124 Threads

In this http://www.ulb.ac.be/sciences/ptm/pmif/Rencontres/specgeom.pdf, for example on p.7 and in many other references, people usually say: we will concentrate on the bosonic part of the Lagrangian in N=1 (sometimes N=2) supergravity. In other incidents, people say, that they are going to...

I will start with a summary of my confusion: I came across seemingly contradictory transformation rules for left and right chiral spinor in 2 books, and am unable to understand what part is Physics and what part is convention. Or is it that one of the two books incorrectly writes the...

In one book of Susskind I found the following claim and I wanted to ask for its basis. Susskind says that each kind of boson gives positive contribution to the cosmological constant (the lighter, the better). Each kind of fermion gives negative contribution to the cosmological constant. Thus...

http://news.discovery.com/space/lhc-keeps-bruising-difficult-to-kill-supersymmetry-150727.htm LHC Keeps Bruising 'Difficult to Kill' Supersymmetry Previous attempts at measuring the beauty quark's rare transformation into a so-called "up quark" had yielded conflicting results. That prompted...

Supersimmetry, by itself, is a neat, elegant concept; I've read somewhere else (think Griffiths' Introduction to Elementary Particles, if memory serves me right) that it allows the various running couplings of the Standard Model to converge to a single value at high enough energies; however...

Hi there, In particle physics there is famous books as Peskin's book " To Quantum Field Theory (Frontiers in Physics) " to learn matrix element amplitude and cross section calculations, like ee -> mu mu. Are there similar references for supersymmetry to learn how to calculate the cross...

Hello, I have one conceptual question. I have been working on Supersymmetry. Now, I understand that twice of supersymmetric transformation is equivalent to translation mathematically(naively). However, I don't quite understand why this should be the case conceptually. Supersymmetric...

Hi everyone, As of late I've been really wanting to push on with my interest in particle Physics by tackling the rather daunting theoretical model that we call supersymmetry. However, to put it simply, I'm not entirely sure where to start! There's so many different textbooks on the subject out...

In the massless case of N=1 simple supersimetry, the states are labeled by the helicity λ and the four-momentum. In this case we have two states in the supermultiplet plus CPT conjugates: |pμ, ± λ> and |pμ, ± (λ-½)> Then there is a λ= {0, ½} supermultiplet (where for example a quark with λ=½...

I'm a novice in SUSY and I'v got a question concerning spontaneous supersymmetry breaking and goldstinos. In Martin's review on page 68 there is a proof of a statement about existence of massless particle when one of ##F_i##'s or ##D_a##'s VEV is not zero. The thing I don't get is why vector...

http://arxiv.org/pdf/1412.0805.pdf Auto-Concealment of Supersymmetry in Extra Dimensions Savas Dimopoulos,a Kiel Howe,a,b John March-Russell,c,a James Scovillec,d aStanford Institute for Theoretical Physics, Department of Physics, Stanford University, Stanford, CA 94305, USA bSLAC National...

I was reading in this book: Supergravity for Daniel Freedman and was checking the part that has to do with Extremal Reissner Nordstrom Black Hole. He was using killing spinors (that I am very new to). I was understanding the theory until he stated with the calculations: He said that the...

I have been looking in SUSY and have seen that the CP violation of B mesons into two muons is one of the key facts that has cast further doubt over SUSY. I don t really understand how the CP violation of B mesons is a sign of SUSY issues, so if you are able to clear this up for me that would be...

Is Supersymmetry still viable in cosmology, given that so far no supersymmetric particles have been found. From Wiki. SUSY is often criticized in that its greatest strength and weakness is that it is not falsifiable, because its breaking mechanism and the minimum mass above which it is...

In 'Supersymmetry in Particle Physics, An Elementary Introduction', the author Ian Aitchison used for several times the following identity: λa(ζ · ρ) + ζa(ρ · λ) + ρa(λ · ζ) = 0. I know that this identity is called Schouten's Identity, which is correct when all the variables are common...

I hope to be able to watch. Should be very interesting! The link below should host the webcast at some point. http://www.perimeterinstitute.ca/node/92581

I wanted to ask wheter there is any progress when it comes to SUSY. Since LHC didn't find any superpartners and LUX found no neutralinos how much space does SUSY have left? I mean it can be fine tuned but that can't be done forever right? Or is there something I don't know that improves...

maybe no supersymmetry... "The new result deals a significant blow to many new physics theories, most notably supersymmetry, a favored idea that suggests each known particle in the Universe has a supersymmetric twin particle that has yet to be discovered" "Although some basic models of the...

Peter Higgs is going to get a Nobel prize for physics, since Higgs boson's existence was confirmed in the experiments in CERN. But I do have some questions: I read the following, but I'm not qualified to say if this is true or not, so I'm asking you for help, and if the following statement is...

We have had several threads that discuss the 2009 prediction of the Higgs boson mass by Shaposhnikov and Wetterich, which used the assumption that quantum gravity is "asymptotically safe". But it's also true that the observed value is within a range predicted by some orthodox supersymmetric...

Hello all, How is it that super symmetry accounts for the Higgs having a mass and what would the 4 remaining Higgs bosons account for?

Are there stringy candidates for reproducing the SM and dark matter etc without low scale supersymmetry?

Hi I know that gravitninos are produced in the Early Universe in reheating (after inflation), is this because the end of inflation/reheating period where the inflaton is oscillating about the minima of the potential is analogous to symmetry breaking?

I just recently seen an article that the recent findings at the LHC seem to disprove supersymmetry. I would like to know how supersymmetry and string theory are connected and what the implications would be if the LHC totally disproves supersymmetry all together?

Hi all, S. Martin's Supersymmetry primer (http://arxiv.org/abs/hep-ph/9709356) is a wonderful source from which to learn SUSY. But, what really causes me (and others around me) huge consternation is Martin's use of mostly plus metric, when particle physicists use the mostly minus metric...

Homework Statement Let \begin{equation} \delta _{1} \, and \, \delta _{2} \end{equation} be two infinitesimal sypersymmetry transformations on xμ compute \begin{equation} [\delta _{1}, \delta _{2} ]x^{μ}. \end{equation} Homework Equations The commutator is: \begin{equation}...

I've often been fascinated by the tantalising nature of muon-catalysed fusion, and have recently been pondering it in the context of supersymmetry. As a Chemist first and foremost, the nearly-chemical nature of the muon-catalysed fusion process really draws my attention. To my understanding...

Can someone explain to me in layman's terms why the Higgs Boson needs to be less than 130 GeV to prove Supersymmetry exists?

We consider a superfield \Phi\left(x^{\mu}, \theta_{\alpha}\right). For a small variation \delta \Phi = \bar{\epsilon} Q \Phi where the supercharge Q_{\alpha} is given by: Q_{\alpha}=\frac{\partial}{\partial \bar{\theta}^{\alpha}}-\left(\gamma^{\mu} \theta \right) _{\alpha} \partial _{\mu}...

I tried searching through but didn't find this asked. If the spin of the particle detected at LHC comes back as 2, for instance, does it mean it's not a higgs boson? There are 5 higgs in supersymmetry, do they all have spin 0?

I've read in the wikipedia supersymmetry page,that supersymmetry is a symmetry which relates fermions to bosons. Can we tell that this means there is aOne-to-One Correspondence between fermions and bosons and we can substitute a fermion with its corresponding boson and vice versa,to get a...

Hi, In SUSY we introduce chiral superfield, vector superfield, then build some invariants and get the SUSY lagrangians which after decomposition into normal fields (F and D terms) gives us for example ordinary QED plus some other terms. And we call this SUSY-QED. I have following question...

I haven't done any supersymmetry before and am probably going to need it in the future (hopefully anyway). Anyway, I've been reading through these online notes: http://www-thphys.physics.ox.ac.uk/people/JosephConlon/LectureNotes/SUSYLectures.pdf I have a problem with p7: (i) What is the...

Researchers failed to find evidence of so-called “supersymmetric” particles, which many physicists had hoped would plug holes in the current theory. Before the start of LHC, I expected early discovery of supersymmetry in the jets+MET signature. Many other theorists also had this belief. But...

http://www.bbc.co.uk/news/science-environment-14680570 Results from the Large Hadron Collider (LHC) have all but killed the simplest version of an enticing theory of sub-atomic physics. Researchers failed to find evidence of so-called "supersymmetric" particles, which many physicists had hoped...

Someone can helpme finding the number of degree of freedom for supergravity n=8?

I have been seeing the word supersymmetry, and I recon that it's the unification of quantum theory and relativity or is ot not?...what is it. I looked it up on wikipedia but didn't really get it, just something about particle spinning and affecting other particles. Could you give me a rough...

Layman's terms what doors will be opened by proving it? What will it say about reality? Will it mean the universe is bigger than we know? Am I right when I tell my kids that Supersymmetry are mirror images of partials that are symmetrical in shape, but heavier than their partner? Thank you

Latest results from the LHC are casting doubt on the theory of supersymmetry http://www.scientificamerican.com/article.cfm?id=beautiful-theory-collides "I'm wouldn't say I'm concerned," says John Ellis, a theorist at CERN, Europe's particle-physics lab near Geneva, who has worked on...

I'm wondering what this book is like in relation to QM, QFT, and String Theory Demystified which have mixed reviews: https://www.amazon.com/dp/0071636412/?tag=pfamazon01-20

Suppose the LHC discovers that EW is dynamically broken by technicolor, topcolor, top quark condensate models. Can these be harmonized with SUSY? If new strongly interacting dyanmics breaks EW, how would that modify SUSY, including SUSY particle content? Or, would discovery of technicolor/top...

http://arxiv.org/abs/1003.2967 Immanuel Kant on Supersymmetry: A Practical Evaluation Alexander Unzicker 4 pages (Submitted on 15 Mar 2010) "A short review of the motivations for supersymmetry in astrophysics and particle physics is given. Despite the amount of theoretical research...

With all kinds of low energy superpartner particles floating around, do we get the same types of atoms and molecules that build up our world? Will the periodic table of elements be larger or smaller? Is this world friendly to the evolution of intelligent life?

Hi there, What is the difference between Space-time Supersymmetry and Supersymmetry? Is Space-time Supersymmetry the same thing as Supergravity? What is Supergravity... All these terms make me very confused... Thanks a lot!

I'm taking an introductory string theory course which focuses on bosonic string theory. The lecturer says to include fermions supersymmetry must be included (aka. superstrings). If we face the event that the LHC fails to find any supersymmetry at TeV scale and the physics community lose faith in...

I hope it's ok to post this here. I have written an introductory book on supersymmetry, which assumes only some basic knowledge in quantum field theory. I made it as detailed and pedagogical as possible. Basically I wrote the book that I wish had been available when I first learned SUSY. The...

I hope it's ok to post this here. I have written an introductory book on supersymmetry, which assumes only some basic knowledge in quantum field theory. I made it as detailed and pedagogical as possible. Basically I wrote the book that I wish had been available when I first learned SUSY. The...

With one, we have 5, what about more than one? What are they? What are the importance of these, phenomenologicaly saying?

In 5 years or so, if LHC fails to find any superpartners, are ALL supersymmetric theories dead? Skippy

Hello all Since there seems that quite many here have followed Professor Srednickis QFT book, I want to ask a couple of question I have from his chapter on Supersymmetry. i) on page 617 he defines the kinetic term of the Chiral Superfields as: L_{\text{kin}} = \Phi^{\dagger} \exp(-2gV)...