# Positivity and causal localizability in higher spin quantum field theories

December 06, 2017

It is shown that the recently introduced positivity and causality preserving
string-local quantum field theory (SLFT) resolves most No-Go situations in
higher spin problems. This includes in particular the Velo-Zwanziger causality
problem which gets in an interesting way related to the solution of zero mass
Weinberg-Witten issue. In contrast to gauge theorie's indefinite metric and
ghosts SLFT uses only physical degrees of freedom and in this way obtains a
simpler and clearer view. This includes the important non-covariant lightcone
gauge which becomes replaced by a fully covariant string field with a lightlike
string directions which, different from gauge fixing parameters, participate in
the in the Lorentz transformation. It reveals that neither the Mexican hat
potential nor the Lie algebra structure of s=1 selfcouplings should be imposed
but rather rather are consequences of the causality and positivity principle of
Local Quantum Physics. As a consequence SLFT provides more profound
explanations than those of Gauge Theory; this affects in particular the raison
d'etre of the Higgs particle. The basic conceptual tool of SLFT is the
S-matrix, which is used to convert the heuristic content of nonrenormalizable
point-local interaction densities into their causality and positivity
maintaining string-like counterpart.

Keywords:

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