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Planck length vs Proton: length comparison

The diameter of a proton is about 1.04 × 10²⁰ times the Planck length. Selected basis: approximate values.

Planck length
Length
Proton
Diameter
Scale
Planck length
1.616 × 10⁻³⁵ mLength
0 - shared origin

The ring marks the true-scale position of the Planck length; it does not show its width. Only the inset is enlarged (×3.32 × 10¹⁹).

Proton
1.682 fmDiameter
0 - shared origin

Both rulers start at the same zero and share one linear scale. Artwork keeps its original proportions.

In perspective1.04 × 10²⁰ times
Measurements, assumptions & sources

Planck length

1.616 × 10⁻³⁵ m - Length; theoretical.

The Planck length is a scale formed from fundamental physical constants. It marks a regime where present theories of gravity and quantum physics are expected to need a unified description.

A theoretical scale formed from the speed of light, reduced Planck constant and gravitational constant. It is not experimentally established as the smallest possible length. The area and volume are derived mathematical scales.

NIST — 2022 CODATA fundamental constants

Proton

1.682 fm - Diameter; measured constant.

A proton is a positively charged particle found in the nucleus of atoms, made up of quarks.

Twice the approximately 0.8409 fm charge radius. The charge distribution has no hard boundary; the illustration is schematic.

NIST — 2022 CODATA fundamental constants

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Fundamental physicsPlanck length1.616 × 10⁻³⁵ mThe Planck length is a scale formed from fundamental physical constants.Fundamental physicsProton1.682 fmA proton is a positively charged particle found in the nucleus of atoms, made up of quarks.MicroscopicHydrogen atom105.8 pmA hydrogen atom is the simplest neutral atom, with one proton in its nucleus and one electron around it.SpaceObservable universe28.21 GpcThe observable universe is the region from which light or other signals have had time to reach us since the early universe.Fundamental physicsPlanck mass21.76 µgThe Planck mass is a theoretical mass scale derived from fundamental constants, significant in discussions of quantum gravity.MicroscopicDNA double helix2 nmDNA is the molecule that stores hereditary information in living organisms.

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Planck length vs Proton