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  • It would be nice to add controls for mobile.
    by gryfft
  • No doubt inspired by George Gamow's Mr.Tompkins in Wonderland (https://en.wikipedia.org/wiki/Mr_Tompkins). That was recommended reading for entering Physics undergrads when I did my degree.
    by dramm
  • Velocity raptor is a free game that accurately simulates the effects of special relativity. It slows down the speed of light to 3m/s and you solve puzzles as a cute dinosaur. https://www.testtubegames.com/velocityraptor.html

    There is also a helpful FAQ which explains all the strange things happening, such as length contraction, time dilation, and color shifting: https://testtubegames.com/srel101.html

    My favorite levels are #18 (which demonstrates time dilation), #26 (which demonstrates space warping), and #42 (which demonstrates retarded time https://en.wikipedia.org/wiki/Retarded_time ). All the levels are unlocked and you can skip to any level.

    by tristanj
  • I know this takes the fun out of it, and it is a fun project, but FWIW the speed of light is not an independent variable. It's woven into the fine-structure constant, the relationship between mass and energy, and how any kind of information is transmitted between objects in the universe.

    This is more of a simulation of what if light was perceived as 5mph for you and kept the same for everyone else.

    It is cool though.

    by timoth3y
  • Whenever I think about light speed being fast, I imagine myself standing at the edge of the solar system and watching a hypothetical photon travel from the Sun to the Earth and taking 8 minutes. Suddenly it doesn't feel like light is really all that fast except at human scales. 5 km/h would be fascinating though.
    by rootusrootus
  • One oddity of Lorentz invariance is that two non-parallel boosts decompose into a boost and spatial rotation.

    I've never quite wrapped my head around this and was hoping to get some insight from this simulation. But afaict, I'm not seeing this effect (press W for a bit, the A for a bit and it's not obvious I'm at a different orientation - if I look down at the ground the gridlines are still axial).

    I don't know if I'm misinterpreting the math, or the simulation, or maybe the simulation is doing something to 'correct' for this behavior so things are more natural, or something else. Does anyone have any insight?

    by greysphere
  • Some time ago I had the following shower thought: "the Speed of Light is pretty slow"

    How i got there:

    The closest major galaxy to the Milky Way is Andromeda, and is 2.5 million! light-years away. And this is the CLOSEST galaxy, the universe is extremely big.

    Of course that as you get closer to C, the traveling object will experience time dilation (relative to observer), so the time passed will be less. At 99.999% C, the traveler would take ~11,000 years to arrive to Andromeda.

    So again, even at 99.999% C, 11K years seems like a LONG time to reach even the closest galaxy.

    My reasoning was: the speed of light is pretty damn slow.

    But then I realized: no, it's not the speed of light that is slow, is my frame of reference.

    For us humans, 11,000 years seems like A LONG time, but for the universe is not that long.

    The universe's age is estimated to be 13.8 billion years. 11,000 years is 0.0000007971 of the age of the universe.

    An average human lives 70 years, 0.0000007971 of that lifespan is approximately ~0.4 hours, or 29 minutes, so it's not that bad.

    So yeah, frame of reference matters.

    by santiagobasulto
  • At first sight, this is remarkably more accurate that the "slower speed of light" game from MIT that was made available all those years ago (~2012).

    Many issues with the MIT game were discussed here:

    https://physics.stackexchange.com/questions/43695/how-realis...

    While the thread lists multiple issues, the issue that I found was with modeling temporal aspects of relativistic doppler (I also reported it on the github repo of the "slower speed of light" project, but that doesn't appear to be maintained):

    https://github.com/MITGameLab/OpenRelativity/issues/17

    In this game, it looks like the temporal component of the Doppler effect is modelled correctly.

    by adamkurkiewicz

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What if the speed of light was 5 km/h? · Birbla