View source for Cubic NLW/NLKG on R4

* Scaling is <math>s_c = 1</math>.
* LWP for <math>s \geq 1</math> by [[Strichartz estimate]]s (see e.g. [[LbSo1995]]; earlier references exist)
** When <math>s=1</math> the time of existence depends on the profile of the data and not just on the norm.
** One has strong uniqueness in the energy class [[Pl-p5]], [[FurPlTer2001]]. This argument extends to other energy-critical and sub-critical powers in dimensions 4 and higher.
** For <math>s<s_c</math> one has instantaneous blowup in the focusing case, and unbounded growth of <math>H^s</math> norms in the defocusing case ([[CtCoTa-p2]]).
* GWP for <math>s=1</math> in the defocussing case [[SaSw1994]] (see also [[Gl1990]], [[Gl1992]], [[Sw1988]], [[Sw1992]], [[BaSa1998]], [[BaGd1997]]).
** In the focussing case there is blowup from large data by the [[ODE method]].

[[Category:Wave]]
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