primordial fluctuations

Primordial fluctuations are tiny variations in the density of matter and energy in the early universe, shortly after the Big Bang. These tiny differences caused some regions to contain slightly more or less matter than others. Over billions of years, gravity amplified these small irregularities, eventually forming galaxies, stars, and planets. Think of them as the universe’s initial “seeds” that set the structure and large-scale pattern of everything we see today. These fluctuations are studied through cosmic microwave background radiation, providing insights into the universe’s earliest moments.