Accelerating Through A Sea Of Heat

If you move fast enough through empty space, the vacuum itself begins to glow with heat. While a stationary observer sees nothing but cold darkness, an accelerating traveler detects a bath of thermal particles.

This phenomenon is known as the Unruh effect and reveals that what we call a vacuum is not universal. Because your motion changes your relationship with the quantum fields around you, you essentially stir up the emptiness into warmth. It turns out that temperature is not an absolute state of the universe, but rather depends on how quickly you are moving. This strange discovery suggests that our perception of reality is deeply tied to our specific path through spacetime.