Pi(π) Day

Syllabus: Important Days (UPSC Prelims)
Source: The Hindu

Pi Day is celebrated every year on 14th March¹ (3/14) to honour the mathematical constant π (pi). The date also marks the birth anniversary of Albert Einstein (1879) and the death anniversary of Stephen Hawking (2018), adding scientific significance to the day.

Why Pi is Important

• π = ratio of a circle’s circumference to its diameter.
• It is an irrational number — its digits go on forever without repeating.
• The symbol π was first used in 1706 by mathematician William Jones, inspired by the words periphery and perimeter.

Indian Contributions

• Aryabhata (476–550 CE) approximated pi as 3.1416 in Aryabhatiya.
• Srinivasa Ramanujan (1914) developed formulas that later helped compute pi to millions of digits.

Applications of Pi

• Used in geometry, engineering, wave mechanics, and architecture.
• Critical for designing circles, domes, bridges, and structural components.
• Space agencies like ISRO use π for orbital calculations, satellite positioning, and spacecraft trajectories.
• Appears in statistical formulas, probability distributions, and natural phenomena.

Why 14 March?

Because 3/14 resembles 3.14, the most recognized approximation of π.

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