INRAe\Olivier Vitrac - last update
Go back to Part 1, jump to Part 3. The project has been forked here.
DISCLAIMER. COVID-19 Particle Collider is an experimental project showing how the propagation of COVID-19 virus can be described as a diffusion-controlled bimolecular chemical reaction (to be infected, you need to meet a contagious/"active" intermediate-product) and subsequent monomolecular ones.
The source and output files are freely available. Results and analyses are presented "AS IS".
COVID-19 Particle Collider ContentUpdatesShort descriptionOffice-like propagationNo significant restrictions, 5 branches, 1 common roomNo significant restrictions, 8 branches, 1 common roomOne restriction, 4 branchesLarge building complexesRepetition #1Repetition #2
First on-line release of Part 2. add link to Part 3.
What does happen when random-walks () are combined with deterministic displacements? The probability to reach the initial position or to meet another particle is very high. The simulation illustrate a combination of confined and almost ballistic displacements with random orientations.
Part 2 illustrates an important result of George Pólya : the probability of rencontre of two particles executing random walks is exactly one in . There is no way to escape the contagious from one single case, as soon as contacts are established after sufficient times. Maintaining the isolation of brings additional time, as well as not moving randomly. Removing confinement must therefore be followed by supplementary protections, and less free and less random displacements. Without precaution, the simulations show that the reappearance of a surge of cases is very likely.
Note: the conditions of transmission are strongly exaggerated in depicted simulations as discussed in part1.
The contagious particle (orange) is located at the end of one branch (2 pm.).
The contagious particle (orange) is located at the end of one branch (10 am.).
The contagious particle (orange) is located in one branch (2 pm.).
The two following simulations generalize previous results to a large complex with rooms and corridors. There is one single contagious particle.
The contagious particle is located in the 10 am. corridor. Note that the density of particles is low, lower than before.
The contagious particle is located in the bottom part of the complex, in the 04 pm. room.