Exploring Cosmic Collisions

Gravitational Interactions

The fundamental driver of galaxy collisions is gravity. Massive objects, like galaxies themselves, exert a gravitational force on each other. This force causes them to accelerate towards one another, increasing their relative speed.

Newton’s Law of Universal Gravitation describes this relationship: F = G * (m1 * m2) / r^2 where F is the force, G is the gravitational constant (6.674 × 10^-11 N(m/kg)^2), m1 and m2 are the masses of the two objects, and r is the distance between their centers.

F = G * (m1 * m2) / r^2

Relativistic Effects

At the speeds involved in galaxy collisions, Newtonian mechanics alone are insufficient. Einstein’s theory of Special Relativity becomes crucial.

As objects approach relativistic speeds (a significant fraction of the speed of light), their mass increases according to the equation m = γm0 where γ is the Lorentz factor (γ = 1 / sqrt(1 - v^2/c^2)) and c is the speed of light.

m = γm0

Collision Dynamics

The simulation demonstrates how galaxies distort and merge during collisions. The gravitational forces cause them to deform, creating tidal tails – streams of stars pulled away from the main bodies.

These collisions are not perfectly elastic; energy is converted into heat and kinetic energy of the resulting galaxy. The distribution of mass also changes significantly.

Large-Scale Structure

Galaxy collisions play a vital role in shaping the large-scale structure of the universe, influencing the formation of galaxy clusters and superclusters.

The simulation highlights how these interactions contribute to the hierarchical clustering model – where smaller structures merge over time to form larger ones. This process is driven by gravity’s relentless pull.

Frequently asked questions

Try it live

Everything above runs in your browser — open SPH Fluid and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.