23 lines
1.2 KiB
Plaintext
23 lines
1.2 KiB
Plaintext
Description:
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This is a simulation of pyramid-shaped objects resting on an immobile surface
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(resembling graphene). Each pyramid is built from spherical particles stacked
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like cannon-balls, or stacked fruit. Ordinarily, the stack does not move
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because the particles at the ground layer are immobilized. However,
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given an initial (small) perturbation the pyramids collapse in an avalanche.
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(In this example, the perturbation is due to shock because we (intentionally)
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did not minimize the system before starting the simulation. This shock
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causes an avalanche to occur approximately 5000 timesteps later.)
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The particles roll down the pyramid and bounce off the "ground". The bouncing
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is due to a repulsive external force which is added artificially.
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(See the "run.in" file.) The simulation looks weird without something
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to bounce off of. So I added a graphene surface at the bottom as scenery.
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(It does not exert any force on the atoms.)
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(Random comment: This could be a fun example to illustrate the Boltzmann
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distribution. Because there is no damping, in a small region, the particle
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heights should eventually approach the Boltzmann distribution for some
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suitable temperature.)
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