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5

$t=0$ is completely consistent. It is simply too boring since it implies that in any unitary theory, $Q_\alpha |\psi\rangle = 0$ for any state $|\psi\rangle$. This is because in this case, we have $$ 0 = \langle\psi|\{ Q_\alpha , Q^\dagger_\alpha \} | \psi \rangle = \| Q^\dagger_\alpha |\psi\rangle \|^2 + \| Q_\alpha |\psi\rangle \|^2 $$ Positivity of ...


2

Yes, there is systematic way called the Noether procedure. Simply you write down all possible 2-derivative fermionic terms with arbitrary coefficients and vary the action using the SUSY transformation rules. Then, you fix the coefficients to obtain the invariance up to a total derivative. When you have 4-derivatives, there are two cases: a. Off-Shell ...


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It's a bit strange because the OP basically repeats the same statement twice. First, he says that he understands it and second, he says that he doesn't. But let's try to avoid these detailed surprising aspects of the question and try to explain what's going on, anyway or again. Type I/II strings have spacetime supercharges $Q_a$ that are constructed purely ...


1

They're not different at all! Seiberg has used the term electric-magnetic duality in the title of his famous paper, too. His duality is an electric-magnetic duality because the duality relates two descriptions and objects that are electrically charged under the gauge group on one side (e.g. quarks and gluons) are mapped to solitons (forms of magnetic ...


1

Your conclusion is true only for $N=1$ supersymmetry. If I have extended supersymmetry, then I can start from the graviton state and end up in a scalar state. What you are saying is true. If I have D-branes, I need to consider projections of all fields into normal and tangent directions onto the D-brane. The world-volume theory of the D-brane will contain ...


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The reason is clearly given in the famous paper "Vacuum configurations for superstrings" - http://www.sciencedirect.com/science/article/pii/0550321385906029 -. Here, I am just copying the introduction of that paper. I cannot tell the reason why with better words. Recently, the discovery [6] of anomaly cancellation in a modified version of d = 10 ...



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