The universe may have started with a bounce, not a bang

Science · Published 25 October 2026 Swipe more like this →

In short: Modern physics suggests space-time isn't a smooth fabric but a woven tapestry of discrete bits. If space has a minimum size, the Big Bang couldn't have been an infinitely small point. Instead, our universe might be part of a cosmic cycle of contraction and explosion.

Loop Quantum Gravity (LQG) proposes that space-time is not continuous as Albert Einstein originally presumed. Instead, it is quantized into discrete units, much like the threads in a sweater. In this framework, distance, area, and volume have minimum possible values—roughly 10^-33 cm for distance, 10^-66 cm² for area, and 10^-99 cm³ for volume. Below these thresholds, space simply cannot exist. This approach differs from string theory because it treats space as quantized rather than a background canvas for vibrating strings. There are approximately 10 to the 99 quanta of volume in every single cubic centimeter of our world.

This granular structure creates a fundamental limit on density. Because space cannot be compressed smaller than 10^-99 cubic centimeters, the universe could not have begun as a singularity of infinite density. When energy reaches a maximum threshold within this minimum volume, LQG suggests it behaves like a saturated sponge: it repels further compression. This implies that the Big Bang was actually a 'Big Bounce,' where a previously contracting universe reached its limit and exploded outward. The universe was large at one point before this contraction began. This theoretical shift addresses why current models struggle with gravity while successfully explaining other particles and forces.

The mechanism relies on 'spin networks'—large quantities of loops and nodes where quanta of volume reside. Time in this model does not flow like a river; it ticks like a digital clock, with each quantum movement occurring every 10^-43 seconds (Planck time). Gravity is perceived as the distortion of these volume quanta when mass and energy are added to the spin foam, rearranging the network's geometry. Nodes where these loops intersect are the specific locations where volume quanta reside. The lines between them represent two-dimensional areas. These combined structures form a spin foam that defines our physical reality.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• Is space itself made of tiny, atomic loops rather than a smooth, continuous fabric?
• Is space-time a smooth fabric or a digital screen of pixels?
• When the entire universe was smaller than a single particle
• The universe began in an extremely hot, incredibly small state
• The universe was once as small as a grapefruit
• Lossy compression discards data we cannot perceive to make digital files significantly smaller.
• Scotland's local government is a complex tapestry of thirty-two unitary authorities and ancient roots.
• How one physicist transformed our understanding of radiation and its impact on human cells
• The hidden math behind how objects move through space
• The London stage that first conquered the darkness with gas
• Logic where truths are resources that can be used up
• How a refugee shield-maker became the architect of the world's most influential plain prose.

More in Physics · More in Science · Latest · A–Z · All topics