It is the use of the height difference of stairs that leads to the endless stairs. Actually, it's a circle on the flat ground.

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Penrose ladder:

It is a famous geometric paradox, which refers to a ladder, which always can't go up or down, but it can't go to the end. It can be regarded as a variant of Penrose Triangle, and the highest or lowest point can never be found on this ladder. Penrose ladder was put forward by British mathematician roger penrose and his father geneticist Leonid Penrose in 1958.

2. Rochester Institute of Technology:

Rochester Institute of Technology, located in Rochester, new york, was founded in 1829. It is the second oldest private polytechnic university in American history with a history of nearly 200 years. It is a prestigious first-class university of science and technology in the United States and the world, featuring high-quality undergraduate education, leading innovation and entrepreneurship education and long-standing enterprise cooperation education.