Gevrey regularity and finite time singularities for the Kakutani–Matsuuchi model

2022 ◽  
Vol 63 ◽  
pp. 103415
Author(s):  
Hantaek Bae ◽  
Woojae Lee ◽  
Jaeyong Shin
2013 ◽  
Vol 178 (3) ◽  
pp. 1061-1134 ◽  
Author(s):  
Angel Castro ◽  
Diego Córdoba ◽  
Charles Fefferman ◽  
Francisco Gancedo ◽  
Javier Gómez-Serrano

2014 ◽  
Vol 16 (02) ◽  
pp. 1350053 ◽  
Author(s):  
ZHOU ZHANG

We provide general discussion on the lower bound of Ricci curvature along Kähler–Ricci flows over closed manifolds. The main result is the non-existence of Ricci lower bound for flows with finite time singularities and non-collapsed global volume. As an application, we give examples showing that positivity of Ricci curvature would not be preserved by Ricci flow in general.


2013 ◽  
Vol 91 (7) ◽  
pp. 548-553 ◽  
Author(s):  
M.J.S. Houndjo ◽  
C.E.M. Batista ◽  
J.P. Campos ◽  
O.F. Piattella

We investigate f(R, T) gravity models (where R is the curvature scalar and T is the trace of the stress–energy tensor of ordinary matter) that are able to reproduce the four known types of future finite-time singularities. We choose a suitable expression for the Hubble parameter to realise the cosmic acceleration and we introduce two parameters, α and Hs, which characterise each type of singularity. We address the conformal anomaly and we observe that it cannot remove the sudden singularity or the Big Brake, but, for some values of α, the Big Rip and the Big Freeze may be avoided. We also find that, even without taking into account the conformal anomaly, the Big Rip and the Big Freeze may be removed thanks to the presence of the T contribution of the f(R, T) theory.


Sign in / Sign up

Export Citation Format

Share Document