The Moving Sofa Problem: 50 Years Unsolved

Ali
5 min readOct 29, 2024
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It was 1966 when renowned mathematician Leo Moser asked a simple question that completely confused the world of mathematics. Moser likely came up with the problem after struggling to move his sofa into a new house and thinking he could solve it simply using mathematics. After a while, however, he was stuck. He then published the problem in an article to recruit other mathematicians to his aid.

Moser had asked a very simple question that affects our everyday lives. After all, most of us have struggled to move a sofa from one room to another at least once. This goes to show the originality of mathematicians, however. While everyone struggles with moving sofas, mathematicians try to solve the problem permanently in order to not come across it in the future.

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In its simplest form, Moser’s problem is as follows: In a two-dimensional “L” shaped corridor with a width equal to that of the width of the sofa, what is the maximum area the sofa can occupy while still being able to turn the L shaped corner?I will simplify the question further. Firstly, imagine the corridor as two-dimensional. Although this goes against real-life intuition, it is necessary for the…

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Ali

Math Teacher. Content Curator. Soccer player. Maradona fan. Mostly write about the lectures I love to learn better. alikayaspor@gmail.com