Big Think Brian Cox breaks down the most mysterious scale in the cosmos
Oct 15, 2025
Dive into the mind-bending world of the Planck length, a measure that reshapes our understanding of size in the cosmos. Discover how Max Planck's universal constants challenge traditional physics and might aid in our communication with extraterrestrial life. Explore the critical role of Planck length in black holes and quantum mechanics, highlighting its influence on matter in extreme environments. Delve into the Chandrasekhar limit, unraveling the mysteries of stellar mass through the lens of quantum mechanics and gravity. A truly cosmic journey!
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Planck Length Reveals Universe Scale
- The Planck length, about 10^-35 meters, is a fundamental scale derived from constants like gravity strength, Planck's constant, and light speed.
- It reveals deep properties of the universe beyond everyday human-scale measurements.
Black Hole Entropy and Planck Area
- Black hole entropy is proportional to its event horizon surface area measured in square Planck lengths.
- This surprising connection emphasizes the Planck length's fundamental role in quantum gravity and information.
Observation Limit at Planck Scale
- Trying to observe objects smaller than the Planck length requires higher energy photons.
- Beyond the Planck scale, the energy density causes black hole formation, limiting resolution and defining a fundamental observation limit.