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| Author(s): |
Alexander Hideki Oniwa Wada
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Física (IF/SBI) |
| Defense date: | 2019-03-27 |
| Examining board members: |
Mario Jose de Oliveira;
Silvio da Costa Ferreira Junior;
José Abel Hoyos Neto;
Jürgen Fritz Stilck;
Andre de Pinho Vieira
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| Advisor: | Mario Jose de Oliveira |
| Abstract | |
We have studied the effects of spatial and temporal disorder at the phase transition between survival and extinction of biological populations. In the first part we studied a four states biological population model. Despite having no disorder, we have seen that its critical behavior is the same of the contact process with (spatial) quenched disorder. In the second part, we studied the reflected fractional Brownian motion, where the interplay between the correlated noise and the reflecting wall results in a power-law singularity in the probability density of the position of the walker. Finally, we deduced the critical properties of the logistic equation with temporal disorder by mapping it onto the reflected fractional Brownian motion. This mapping allow us to understand how long-range correlations change the critical behavior of this system. (AU) | |
| FAPESP's process: | 15/02100-8 - Phase transitions and critical phenomena in stochastic models describing population dynamics |
| Grantee: | Alexander Hideki Oniwa Wada |
| Support Opportunities: | Scholarships in Brazil - Doctorate |