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Abstract Mercury’s orbit can destabilize, generally resulting in a collision with either Venus or the Sun. Chaotic evolution can causeg1to decrease to the approximately constant value ofg5and create a resonance. Previous work has approximated the variation ing1as stochastic diffusion, which leads to a phenomological model that can reproduce the Mercury instability statistics of secular andN-body models on timescales longer than 10 Gyr. Here we show that the diffusive model significantly underpredicts the Mercury instability probability on timescales less than 5 Gyr, the remaining lifespan of the solar system. This is becauseg1exhibits larger variations on short timescales than the diffusive model would suggest. To better model the variations on short timescales, we build a new subdiffusive phenomological model forg1. Subdiffusion is similar to diffusion but exhibits larger displacements on short timescales and smaller displacements on long timescales. We choose model parameters based on the behavior of theg1trajectories in theN-body simulations, leading to a tuned model that can reproduce Mercury instability statistics from 1–40 Gyr. This work motivates fundamental questions in solar system dynamics: why does subdiffusion better approximate the variation ing1than standard diffusion? Why is there an upper bound ong1, but not a lower bound that would prevent it from reachingg5?
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This content will become publicly available on December 12, 2025
Stomatal Parameters in a Changing Environment
Summary statement We recommend that stomatal slope parameters (g1) be inferred by inversion so that variations ing1may be attributed to variations physiological and environmental conditions. Understandingg1will advance predictions of plant gas exchange and performance under global climate.
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- Award ID(s):
- 2045610
- PAR ID:
- 10574121
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Plant, Cell & Environment
- ISSN:
- 0140-7791
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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