Lightspeed on Your Desktop


Above, I looked at the four effects Lightspeed can model and apply to your object. By default, all of the effects are selected when you start up. If you want to change which effects are being modeled, you can go to the Warp menu item and select any combination of Lorentz contraction, Doppler red/blue shift, Headlight effect or Optical aberration. So, you can select only the Lorentz contraction and see what it looks like at 90% of the speed of light (Figure 6).

Figure 6. Looking at Just Lorentz Contraction at .9c

You have quite a bit of control over the camera as well in Lightspeed. You can select the focal length of the camera lens, going from 28mm to 200mm. You even can set a custom lens focal length by selecting Camera→Lens→Custom. You can set the position of the camera precisely by clicking Camera→Position. This displays a pop-up dialog, where you can set the exact x, y and z values for its location (Figure 7).

Figure 7. Changing Camera Position for a Better View

You can select what information is displayed on the screen by selecting the menu item Camera→Info display. You can have the velocity, the time, the gamma factor and/or the frame rate displayed on the screen.

The default background color is black, but you can change it to gray, white or very white. This display is an OpenGL display, so you can select the rendering mode. The default is shaded, but you can change it to wireframe rendering.

One of the really cool options is that you can spawn off other cameras by selecting Camera→Spawn camera. This lets you see your object from several different angles at the same time. So, now you can see what it looks like coming and going at the same time (Figure 8).

Figure 8. Setting Up Multiple Cameras for Different Perspectives

Once you have the speed and the relativistic effects set, you probably want to interact with the object a bit to see how it looks from different directions and so on. If you click the left mouse button and drag around, your object will be rotated around. If you click the left mouse button and press Shift at the same time, the camera view will be moved around, pointing in different directions. You can move the camera itself by clicking the middle mouse button and moving it up and down or left and right. You can move the camera in and out from the object by clicking the right mouse button and sliding up and down. If you completely mess up your view, you always can go back to the defaults by clicking the menu item Camera→Reset View.

So, remember this program when you are studying special relativity. Now you finally can see what it would really look like if you were traveling down the tunnel with the protons in the LHC or what the Starship Enterprise would look like as it flew by at sublight speed.


Joey Bernard has a background in both physics and computer science. This serves him well in his day job as a computational research consultant at the University of New Brunswick. He also teaches computational physics and parallel programming.


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I've been trying to figure

Orlando IT Services's picture

I've been trying to figure out how to do this for the last couple of hours...appreciate the insight.

With the default settings at

Ivor's picture

With the default settings at 299,792,457m/s it makes no sense to me. I need Carl Sagan to explain this. Perhaps taking into account each of the four aspects and how they played into it.

The features all work

mikkela's picture

The features all work together to make an incredible in sky