No physical object can exceed the speed of light c = 300,000 km/s. As you approach c, your Lorentz factor γ = 1/√(1 - v²/c²) grows infinitely.

• Time Dilation: Moving clocks tick slower.
• Length Contraction: Distances in front of you physically compress.
• Doppler Shift: Light ahead blueshifts, light behind redshifts.

Gravity is NOT a magnetic tug; it is the physical bending of 4D spacetime fabric by heavy mass Δt_0 = Δt_∞ √(1 - r_s/r).

• Photon Sphere (1.5 r_s): Light orbits in circles.
• Event Horizon (r_s): Point of no return. Escape velocity exceeds c.
• Spaghettification: Extreme gravitational tidal gradients rip objects into atomic strings.

Einstein-Rosen bridges connect two distant coordinates through higher-dimensional folded space.

• Folded Paper: Walk across millimeters instead of light-years.
• Exotic Matter: Negative energy density required to keep the throat propped open without collapsing.

Why does the astronaut age slower than the Earth twin? Because turning the rocket around requires physical acceleration.

• The traveling twin changes reference frames.
• In spacetime geometry, the bent path taken by the astronaut is shorter than the straight unaccelerated path of the Earth sibling!