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Pseudo-chemotaxis of active Brownian particles competing for food

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 نشر من قبل Abhinav Sharma
 تاريخ النشر 2019
  مجال البحث فيزياء
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Using Brownian dynamics simulations, the motion of active Brownian particles (ABPs) in the presence of fuel (or food) sources is studied. It is an established fact that within confined stationary systems, the activity of ABPs generates density profiles that are enhanced in regions of low activity, which is generally referred to as anti-chemotaxis. We demonstrate that -- contrary to common believes -- in non-stationary setups, emerging here as a result of short fuel bursts, our model ABPs do instead exhibit signatures of chemotactic behavior. In direct competition with inactive, but otherwise identical Brownian particles (BPs), the ABPs are shown to fetch a larger amount of food. From a biological perspective, the ability to turn active would, despite of the absence of sensoric devices, encompass an evolutionary advantage.


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