Welcome to the Riod Simulation Site
The purpose of this site is to provide a hub to announce development and results updates and link to other related sites and activities.
Here is an introductory presentation on the Riod simulation and some of the internal workings.
I have been working on this simulation now for decades and as the history section of the Riod user manual (riodreadme.pdf ) states: "Work began on this simulation quite innocently in the early 1980s, while the author was a graduate student studying nuclear reaction physics at the University of Notre Dame." The simulation is quite crude and is by no means not even within many orders of magnitude of state-of-the-art. However, it does provide a creative outlet and fuels my continued interest in Physics and Cosmology (Photo of the author around the fall of 1983).
Here are some features of the simulation:
Here is an introductory presentation on the Riod simulation and some of the internal workings.
I have been working on this simulation now for decades and as the history section of the Riod user manual (riodreadme.pdf ) states: "Work began on this simulation quite innocently in the early 1980s, while the author was a graduate student studying nuclear reaction physics at the University of Notre Dame." The simulation is quite crude and is by no means not even within many orders of magnitude of state-of-the-art. However, it does provide a creative outlet and fuels my continued interest in Physics and Cosmology (Photo of the author around the fall of 1983).
Here are some features of the simulation:
- "Unlimited" numbers of objects (but IO formatting limits things to N<100,000) with full object pair calculations. I have run simulations with 20,000 objects in scenarios of mini galactic halos and on a fast PC, these scenarios complete in about a month.
- Options for classical or relativistic calculations
- Simulation can be restarted from the point it was stopped without losing any calculations.
- Temporal causality provisions (time retarded forces)
- Many extended object initial condition options. Options as of 8/24/2018 include being able to create specific mass distribution profiles (e.g., Exponential, NFW, Jaffe, Einasto-like and Plumber distribution profiles).
- Object size and time delta control
- Utilizes up to 20 computing cores or threads using OpenMP extensions
- Options for when objects get too close, modified forces to allow inelastic collisions, elastic collisions, and object pass-through modes and other more exotic modes.
- Self-contained Windows code, no installation needed.
- Rich logging with improved control of status and significant simulation events with status and console logs now saved periodically in the data directories as separate files.
- Ability to plot and animate the output files (and create screen captures which with some effort can create videos)
Here is the latest Riod news:
8/30/2021: Riod Simulation Description Presentation
6/30/2022: Updated Users manual: riodreadme.pdf
11/25/2019: Video showing a spherically propagating mass wave in an 20,000 particle NFW dark matter halo:
Many-Body Gravitational Simulation: Spherically Propagating Mass Wave
7/9/2019: A new video can be found here: 20,000 Particles Collapse With Pulsing Core
7/27/2017: My latest video can be found here: Virial Radius Heartbeat Sounds
6/30/2022: Updated Users manual: riodreadme.pdf
11/25/2019: Video showing a spherically propagating mass wave in an 20,000 particle NFW dark matter halo:
Many-Body Gravitational Simulation: Spherically Propagating Mass Wave
7/9/2019: A new video can be found here: 20,000 Particles Collapse With Pulsing Core
7/27/2017: My latest video can be found here: Virial Radius Heartbeat Sounds