# What kinds of inconsistencies would one get if one starts with Lorentz noninvariant Lagrangian of QFT?

What kinds of inconsistencies would one get if one starts with Lorentz noninvariant Lagrangian of QFT? The question is motivated by this preprint arXiv:1203.0609 by Murayama and Watanabe.

Also, what is the basic difference between

• a theory that is non-relativistic approximation to relativistic theory, and

• a fundamentally Lorentz non-invariant theory?

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