Einstein’s theory of special relativity has been blowing the minds of physics lovers for a century now, having transformed how we think about space and time. Some pretty strange effects occur at near-light-speed (time dilates, length contracts), and these are so counter-intuitive and at odds with our everyday experience of the world — we just don’t travel at those kinds of velocities — that it can be difficult to wrap our heads around such concepts.
Sure, once someone walks you through the relevant algebraic equations, the theory and its repercussions become a bit more clear, but what if you don’t happen to speak math? Enter MIT’s Game Lab — yes, MIT has a game lab! — with a new project called A Slower Speed of Light, to help players learn about relativistic effects conceptually, rather than mathematically.
There are a couple of fundamental ideas in special relativity: First, anything that
happens in the universe involves both three-dimensional space and the fourth
dimension of time, or as it’s now known, the space-time continuum.
Second, we can’t know that an event has occurred until information about that event reaches us. Light travels incredibly fast — 669,600,000 mph, to be precise — but there is still a delay before news of the event reaches the observer and enables him or her to react to the information.
Then there’s the matter of reference frames. In physics, a reference frame simply denotes where an observer happens to be standing; it’s similar in concept to a point of view.
In Einstein’s equations, there is no such thing as a universal, stationary
frame of reference because every object in the universe is constantly moving
through time and space.
The laws of physics still apply equally in every individual frame of reference, and the speed of light is constant in all frames of reference. But strange things start to happen near the speed of light — e.g., moving away from an object at those velocities means you will perceive that object as being closer. Weird, right?
Also, whenever an object with mass is in motion, its measured length will shrink in
proportion to its speed; the faster it goes, the more its length will shrink — the aforementioned length contraction. No object with mass can reach exactly light speed, but if it did, it would shrink to nothing.
Because time and space are linked, something similar happens with time: it slows down with motion — time dilation — until time, too, dilates to nothing. None of this is apparent to the object that is moving, only to an outside observer in a different reference frame.
Length contraction and time dilation mean that there can be no such thing as two
simultaneous events, when each is viewed from a different frame of reference.
Space and time are not fixed. The distance between two points in space, and the
time between two events, depends upon the observer’s point of view.
Confused yet? If you haven’t encountered these concepts before, special relativity can be a bit of a conceptual challenge. A Slower Speed of Light lets you see how relativistic principles play out in a virtual sphere.
The objective of the game is to collect 100 orbs as you move through the game space, except with every orb you collect, the speed of light gets slower. That’s when things get interesting. Per Ethan Siegel at Starts With a Bang:
The colors start to change, distances start to appear counterintuitive, and, well, you’re challenged to develop an intuition for moving at relativistic speeds, because the speed of light has slowed! When you’ve successfully collected all 100 orbs, you’re rewarded with the red/blueshifts turned off, and you merely observe the effects of the Lorentz transformations, which are still incredibly freaky!