## Overview - **Concept**: Planck Scale and Units - Planck Length - Planck Time - Planck Mass - **Key Figures**: - **Field of Research**: theoretical physics ## Summary The Planck scale is the smallest meaningful scale in the known universe, below which our current understanding of physics breaks down. It is named after the German physicist Max Planck, who made significant contributions to the field of quantum mechanics. The Planck scale is defined by several fundamental constants of nature: 1. Planck Length (`Lp`): This is the smallest length scale in the universe, approximately $1.616229 × 10^-35$ meters. Below this length scale, the fabric of space-time is thought to become fundamentally distorted, and our current theories, including general relativity and quantum mechanics, are incompatible. 2. Planck Time (`tp`): This is the shortest time interval that can be meaningfully described, approximately $5.39106 × 10^-44$ seconds. It is the time it takes for light to travel the Planck length in a vacuum. 3. Planck Mass (`Mp`): This is the smallest mass that can be meaningfully considered, about $2.17647 × 10^-8$ kilograms. 4. Planck Energy (`Ep`): The energy associated with the Planck mass, which is around 1.95608 × 10^9 joules. The Planck scale is significant in theoretical physics because it marks the limits of our current understanding of the fundamental forces and particles in the universe. It's a scale where the effects of quantum gravity become important, and a theory of quantum gravity is needed to describe physical phenomena accurately. Many physicists are actively working on theories such as string theory and loop quantum gravity to address the mysteries of the Planck scale and provide a unified framework for understanding the fundamental forces of the universe at this tiny scale. ## References - https://en.wikipedia.org/wiki/Planck_units