https://doi.org/10.1140/epjc/s10052-016-4355-7
Letter
Stability in higher-derivative matter fields theories
1
Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Joliot-Curie 6, Dubna, 141980, Russia
2
Department of General Relativity and Gravitation, Institute of Physics, Kazan Federal University, Kremlevskaya street 18, Kazan, 420008, Russia
* e-mail: tpv@theor.jinr.ru
Received:
19
August
2016
Accepted:
1
September
2016
Published online:
12
September
2016
We discuss possible instabilities in higher-derivative matter field theories. These theories have two free parameters 
and 
. By using a dynamical system approach we explicitly demonstrate that for the stability of Minkowski space in an expanding universe we need the condition 
. By using the quantum field theory approach we also find an additional restriction for the parameters, 
, which is needed to avoid a tachyon-like instability.
© The Author(s), 2016
