“…Intracellular phenomena occur over a range of timescales (upper, green), from bacterial division times as fast as 10 minutes (Rocha, 2004) down to physico-chemical fluctuations on the order of femto- to nano-seconds. The residence times of ultra-weak protein dimers (lower, left) are comparable to the timescales of elementary chemical reactions (Gruebele and Zewail, 1990) and protein conformational fluctuations (Bredenbeck et al, 2003), whereas higher-order clusters can last an order of magnitude longer (lower, center), on par with enzyme-catalyzed reactions (Smejkal and Kakumanu, 2019). This ultra-weak clustering regime operates below the timescales of phase separated droplets (Molliex et al, 2015; Tang et al, 2021), cell signaling (Asthagiri and Lauffenburger, 2003), and percolated networks (Ramm et al, 2022; Zia et al, 2014) (lower, right), which are sufficiently durable to be measured in vivo .…”