Recent content by nidnus

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    Sunset / sunrise diagrams in 2D

    Doesn't really matter. The integral is as stated above. If you want to you can think about it as phi four theory in 2D.
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    Sunset / sunrise diagrams in 2D

    Hi, Can anyone point me to a reference where the complete amplitude for a sunrise diagram in 2D with generally different masses is written down. That is, I want the value of the following integral $$ \int d^2k d^2l \frac{1}{(k^2-m_1^2)(l^2-m_2^2)((p-k-l)^2-m_3^2)} $$ where p is the...
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    Dimensional regularization vs momentum cutoff

    Hi Chris, Thanks for your answer. Indeed, the terms I find correspond to mass renormalization. However, I would expect ##\delta m^2 ## to be zero since its a susy model. What is more, the ##\delta m^2## in hard cutoff is different for boson and fermions implying that susy is broken which should...
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    Dimensional regularization vs momentum cutoff

    Hi everyone, I have a 2D sigma model with supersymmetry on the worldsheet. It has both cubic and quartic interactions and I'm interested in the one loop correction to the worldsheet masses. When I calculate this with dimensional regularization I find that everything is zero as expected. In...
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    Surface terms in loop integrals (2D)

    Hi everyone, Say I have a 2D one loop integral of the form $$ I^s_n(\Delta)=\int d^2 l \frac{(l^2)^s}{(l^2-\Delta)^n} $$ Using that ##1 = \frac{1}{2} \partial_\mu l^\mu##, I can relate say $$I^1_2(\Delta)=I^0_1(\Delta)$$ + total derivative term. In dimensional regularization one usually...
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    IR terms from massless modes in 2D sigma model

    Hi All, My first post here. As far as I've understood there are problems with massless states in two dimensions. In the problem I am working on I have a 2D (non linear) sigma model with a lot of symmetries. The worldsheet fields come as heavy and massless. My main interest is to...
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