Definition:Fermat's Spiral

Definition

Fermat's spiral is the locus of the equation expressed in Polar coordinates as:

$r^2 = a^2 \theta$

For negative $r$, the figure appears as:

and when plotted both together:

Also known as

Some sources refer to Fermat's Spiral as a parabolic spiral.

Also see

• Results about Fermat's spiral can be found here.

Source of Name

This entry was named for Pierre de Fermat.

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): parabolic spiral
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): Fermat's spiral
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): spiral
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): Fermat's spiral
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): spiral
• 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): parabolic spiral