Unitarity violation at the Wilson-Fisher fixed point in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mn>4</mml:mn><mml:mo>−</mml:mo><mml:mi>ε</mml:mi></mml:mrow></mml:math>dimensions
Physical review. D/Physical review. D.