Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

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.

  1. What is the physical meaning of this negative mass I am getting?

  2. Does this mean the parameters I am putting in is giving an unphysical spectrum?

share|improve this question
add comment

2 Answers 2

up vote 1 down vote accepted

Negative fermion masses just mean that there is a relative phase between some terms in the Lagrangian. This doesn't usually mean that anything is wrong.

share|improve this answer
add comment

Negative mass (equivalently tachyonic states) mean that the spectrum was computed in an unstable (and unphysical) pseudo-vacuum, which would undergo a rapid phase transition.

This means that the fields must be shifted (e.g., broken symmetry in Higgs) and/or linearly transformed by a Bogoliubov transformation (e.g., superconductivity) before they are Fourier expanded in terms of creation and annihilation operators used to find the spectrum.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.