1. Introduction
2. Model description
2.1. Network construction
Figure 1. Schematic illustration of the random network with stochastic rewiring. Black links represent the initial network at time ${T}_{0}$​. At each subsequent time step, existing links are selected for rewiring with probability ${p}_{{\rm{rewire}}}$; links scheduled for removal are shown in light gray. For each removed link, a new connection is added between a randomly chosen pair of nodes not previously connected, depicted in dark red. This process preserves the mean degree while generating a time-varying interaction topology, providing a controlled way to find the effect of temporal connectivity changes on synchronization dynamics. |
2.2. Interpretation
2.3. Synchronization measure
3. Results
Figure 2. Forward (dark blue) and backward (light blue) synchronization transitions in static random networks with $N=100$ oscillators. Panel (a) shows the order parameter curves for a network with mean degree $k=16$, while panel (b) corresponds to a denser network with $k=40$. In both cases, increasing and decreasing the coupling strength reveal the characteristic hysteresis loop associated with explosive synchronization. The discontinuous jumps and separated branches confirm bistability and demonstrate that explosive synchronization already exists in the static baseline networks. |
Figure 3. Two-dimensional map of the forward order parameter $R$ for the network with mean degree $k=16$, shown in the $(f,\lambda )$ plane for six rewiring probabilities. Panels (a)–(f) correspond to ${p}_{\mathrm{rewire}}=0.01,0.05,0.1,\,0.2,\,0.3,\,0.4$, respectively. The rewiring frequency $f$ is plotted on a logarithmic scale to highlight behavior across multiple time scales. Dark red indicates low coherence (asynchronization), while dark blue denotes full synchronization, with intermediate colors representing partial coherence. The maps show that increasing rewiring probability and switching frequency progressively favors abrupt, explosive transitions over smooth continuous ones. |
Figure 4. Forward and backward $R$ parameters for the network with $k=16,$ shown for three switching frequencies: $f=50$ (left), $f=2.5$ (middle), and $f=0.025$ (right). Panels correspond to different values of the rewiring probability: (a) ${p}_{{\rm{rewire}}\,}=0.01$, (b) ${p}_{{\rm{rewire}}\,}=0.05$, (c) ${p}_{{\rm{rewire}}\,}=0.1$, and (d) ${p}_{{\rm{rewire}}\,}=0.4$. The separation between forward and backward branches illustrates how explosive synchronization emerges only for specific combinations of rewiring probability and switching frequency. |
Figure 5. Spatiotemporal dynamics of the network and the corresponding local order parameter (${R}_{L}\,$) for $k=16$ and ${p}_{{\rm{rewire}}\,}=0.1$, shown for forward transitions (first row) and backward transitions (second row). Panels correspond to different coupling strengths: (a), (d) $\lambda =0.45$, (b), (e) $\lambda =0.5$, and (c), (f) $\lambda =0.55$. The figure highlights how the network dynamics and local synchronization evolve with varying $\lambda $ during forward and backward transitions. These spatiotemporal dynamics provide a direct visual signature of bistability and hysteresis underlying explosive synchronization. |
Figure 6. Two-dimensional map of the forward order parameter $R$ for the network with mean degree $k=40$, shown in the $(f,\lambda )$ plane for six rewiring probabilities. Panels (a)–(f) correspond to ${p}_{\mathrm{rewire}}=0.01,{\rm{}}0.05,{\rm{}}0.1,\,0.2,\,0.3,\,0.4$, respectively. The rewiring frequency $f$ is plotted on a logarithmic scale to highlight behavior across multiple time scales. Dark red indicates low coherence (asynchronization), while dark blue denotes full synchronization, with intermediate colors representing partial coherence. This figure demonstrates that dense connectivity enhances the robustness of abrupt transitions. |
Figure 7. Forward and backward $R$ parameters for the network with $k=40,$ shown for three switching frequencies: $f=50$ (left), $f=2.5$ (middle), and $f=0.025$ (right). Panels correspond to different values of the rewiring probability: (a) ${p}_{{\rm{rewire}}\,}=0.01$, (b) ${p}_{{\rm{rewire}}\,}=0.2$, (c) ${p}_{{\rm{rewire}}\,}=0.4$. The pronounced hysteresis loops at intermediate rewiring probabilities indicate the strongest explosive behavior, while weak or strong rewiring reduces the bistable region. |
Figure 8. Two-dimensional map of the forward order parameter $R$ in the ($k,\lambda $) plane for the network, shown for four rewiring frequencies from left to right: $f=20,\,1,\,0.1$, and $0.01$. Panels (a)–(c) correspond to different rewiring probabilities: ${p}_{\mathrm{rewire}}=0.01,\,0.1$, and $0.3$, respectively. These diagrams summarize how network density and temporal rewiring jointly determine whether synchronization is continuous or explosive across parameter space. |
Figure 9. Hysteresis area between forward and backward transitions as a function of mean node degree $k$, shown for three rewiring frequencies from left to right: $f=20,1$, and $0.01$. Panels (a)–(c) correspond to different rewiring probabilities: ${p}_{\mathrm{rewire}}=0.01,0.1,$ and $0.3$, respectively. The variation of the hysteresis area quantitatively measures the strength of explosive synchronization and confirms that bistability is maximized for intermediate-to-high rewiring and rapid switching. |


