scholarly journals The numerical response: rate of increase and food limitation in herbivores and predators

2002 ◽  
Vol 357 (1425) ◽  
pp. 1233-1248 ◽  
Author(s):  
Peter Bayliss ◽  
David Choquenot
Keyword(s):  
Food Availability ◽  
Population Regulation ◽  
Environmental Variability ◽  
Food Limitation ◽  
Numerical Response ◽  
Limiting Factors ◽  
Biological Interactions ◽  
Equilibrium Dynamics ◽  
Rate Of Increase ◽  
Non Equilibrium

Two types of numerical response function have evolved since Solomon first introduced the term to generalize features of Lotka–Volterra predator–prey models: (i) the demographic numerical response, which links change in consumer demographic rates to food availability; and (ii) the isocline numerical response, which links consumer abundance per se to food availability. These numerical responses are interchangeable because both recognize negative feedback loops between consumer and food abundance resulting in population regulation. We review how demographic and isocline numerical responses have been used to enhance our understanding of population regulation of kangaroos and possums, and argue that their utility may be increased by explicitly accounting for non–equilibrium dynamics (due to environmental variability and/or biological interactions) and the existence of multiple limiting factors. Interferential numerical response functions may help bridge three major historical dichotomies in population ecology (equilibrium versus non–equilibrium dynamics, extrinsic versus intrinsic regulation and demographic versus isocline numerical responses).

scholarly journals Temperature chaos is present in off-equilibrium spin-glass dynamics

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Marco Baity-Jesi ◽  
Enrico Calore ◽  
Andrés Cruz ◽  
Luis Antonio Fernandez ◽  
José Miguel Gil-Narvion ◽  
...  
Keyword(s):  
Spin Glass ◽  
Dynamic Effect ◽  
Large Degree ◽  
Equilibrium Temperature ◽  
Experimental Conditions ◽  
Temperature Changes ◽  
Equilibrium Dynamics ◽  
Glass Dynamics ◽  
Extreme Sensitivity ◽  
Non Equilibrium

AbstractExperiments featuring non-equilibrium glassy dynamics under temperature changes still await interpretation. There is a widespread feeling that temperature chaos (an extreme sensitivity of the glass to temperature changes) should play a major role but, up to now, this phenomenon has been investigated solely under equilibrium conditions. In fact, the very existence of a chaotic effect in the non-equilibrium dynamics is yet to be established. In this article, we tackle this problem through a large simulation of the 3D Edwards-Anderson model, carried out on the Janus II supercomputer. We find a dynamic effect that closely parallels equilibrium temperature chaos. This dynamic temperature-chaos effect is spatially heterogeneous to a large degree and turns out to be controlled by the spin-glass coherence length ξ. Indeed, an emerging length-scale ξ* rules the crossover from weak (at ξ ≪ ξ*) to strong chaos (ξ ≫ ξ*). Extrapolations of ξ* to relevant experimental conditions are provided.

scholarly journals Epidemic growth and Griffiths effects on an emergent network of excited atoms

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
T. M. Wintermantel ◽  
M. Buchhold ◽  
S. Shevate ◽  
M. Morgado ◽  
Y. Wang ◽  
...  
Keyword(s):  
Complex Systems ◽  
Power Laws ◽  
Excitation Density ◽  
Griffiths Phase ◽  
Many Body ◽  
Excited Atoms ◽  
Equilibrium Dynamics ◽  
Many Body Systems ◽  
Excitation Number ◽  
Non Equilibrium

AbstractWhether it be physical, biological or social processes, complex systems exhibit dynamics that are exceedingly difficult to understand or predict from underlying principles. Here we report a striking correspondence between the excitation dynamics of a laser driven gas of Rydberg atoms and the spreading of diseases, which in turn opens up a controllable platform for studying non-equilibrium dynamics on complex networks. The competition between facilitated excitation and spontaneous decay results in sub-exponential growth of the excitation number, which is empirically observed in real epidemics. Based on this we develop a quantitative microscopic susceptible-infected-susceptible model which links the growth and final excitation density to the dynamics of an emergent heterogeneous network and rare active region effects associated to an extended Griffiths phase. This provides physical insights into the nature of non-equilibrium criticality in driven many-body systems and the mechanisms leading to non-universal power-laws in the dynamics of complex systems.

Non-equilibrium dynamics of colloids on disordered substrates

2003 ◽  
Vol 318 (1-2) ◽  
pp. 146-151 ◽  
Author(s):  
Jiangxing Chen ◽  
Yigang Cao ◽  
Zhengkuan Jiao
Keyword(s):  
Equilibrium Dynamics ◽  
Non Equilibrium
Sign in / Sign up

Export Citation Format

Share Document