Speed of light in unity?

Is it possible to make a rigidbody to move with the speed of light?

 

I just wanted to test the speed of light in a controlled space like a simulation in a game engine

 

"test" the speed of light?
What are you trying to test? If you're trying to see what happens to space when moving close to the speed of light, a few approaches may work, either going for non-euclidien spaces (like hyperbolic space), by hard-coding a physics engine taking relativistic effets into account, or simply use the Lorentz transform into a tiny simulation.

Now many other relativistic effects (cherenkov radiation, snell's law, and so on) are entirely other things to work on and won't happen by themselves by simply making a GameObject moving really fast. You can, if you want, (I have not tested though) set the velocity of anything to 3.10^8 m/s, and the simple fact that it's possible should hint you to the fact that it's not reliable. Also, the xyz coordinates of unity aren't exact meters and seconds, because they only scale within range of float rounding errors (forget about quantum effects!) and float overflow (not much cosmology).

I'm not sure that a simulation engine is the best place to test any real-life hypothesis, only to build and tests models that would take the engine limitations into account. You kinda have to code the behavior in advance, and anything you'd note from said simulation is to be attributed to the engine or the model you chose to apply.

If you want mathematical ressources on general relativity, I'll point you towards this video that details the demonstration, keeping in mind that Einstein's equation is not the whole story (Fridman correction because it's so complicated that even Einstein made mistakes, Minkovski / deSitter Space or anti-deSitter Space (tough choice !), and so on)... And I haven't mentioned angular momentum nor Doppler effects.

The best way to test light is in a laser lab.

At least in an empty scene, because good luck avoiding planets ;D

 

hey, did you ever get this speed of light project going?

 

no

 

no, sorry. You can leave a feedback here on my present project(steam release): https://forum.unity.com/threads/wip-steam-release-survival-the-ocean-a-pirate-game.978855/

 

You just need to raycast longer in one frame tick than the light moves in the same time span

 

Nothing can be faster than light even raycast, that's what physics tells us.

 

It was a joke

 

Mine too.

 

Time stops at the speed of light, so just freeze everything else.

 

Time.timeScale = 0;

 

And also the mass of rigidbody should be infinite

 

Rigidbody.mass = Mathf.Infinity;

Now we just need to scale the object along movement direction.