Redshift is made on Processing 1.5.1. It uses the ControlP5 library. It has been tested on Processing 2.2.1 with corresponding library.
The program is a demonstration of the redshift effect in space.
The redshift effect is the association of two effects that change frequency of electro-magnetic waves (light) in space:
- The Doppler effect
- The space extansion effect
The Doppler effect can be experienced with sound. When a car is approaching, the sound frequency is higher. And when the car moves away, the sound frequency is deeper.
The same effect is observed with electro-magnetic waves and change the color of the light.
The space extansion effect is less famous. The universe is expanding and reduce the frequency of the electro-magnetic waves moving in it. As the frequency of the electro-magnetic waves change, the color of light change as well. It can be detected with very far objects.
This application allow us to move an object which sends green light. The light goes in every directions but each point of light emitted has a different frequency so a different color depending on the movement of the sender relative to the earth. Indeed, the scale of the effect is exagerated in the application and the frequency of the electromagnetic waves are limited to the visible spectrum.
See there for more info: Red Shift: https://en.wikipedia.org/wiki/Redshift Light: https://en.wikipedia.org/wiki/Light
Interface:
The light received by Earth allow use to look the difference between the color sent and the color received. With that difference we are able to know the speed of the sender.
Many parameters are available to modify the light emmitted. For example, the space expansion effect can be activated with the GeneralRedShift button.
In adition, there are several presets of configuration to help use the application.
- Download Processing https://processing.org/download/
- Download and copy controlP5 library in sketchbook ~/sketchbook/librairies http://www.sojamo.de/libraries/controlP5/ (to find your sketchbook folder, start processing: File>Preferences Sketchbook location)
- Clone this repository
- Start Processing ./processing
- Open Redshift.pde