astronomy

Kokichi Sugihara

Kokichi Sugihara is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Kokichi Sugihara rather than just read about it. In short: Kōkichi Sugihara (Japanese: 杉原厚吉, born June 29, 1948, in Gifu Prefecture) is a Japanese mathematician and artist known for his three-dimensional optical illusions that appear to make marbles roll uphill, pull objects to the highest point of a building's roof, and make circular pipes look rectangular. His illusions, which often involve videos of three-dimensional objects shown from carefully chosen perspectives, won…

Key takeaways

Kokichi Sugihara belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Kokichi Sugihara to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Kokichi Sugihara from memory before moving on to harder problems.

Reference excerpt

Kōkichi Sugihara (Japanese: 杉原厚吉, born June 29, 1948, in Gifu Prefecture) is a Japanese mathematician and artist known for his three-dimensional optical illusions that appear to make marbles roll uphill, pull objects to the highest point of a building's roof, and make circular pipes look rectangular. His illusions, which often involve videos of three-dimensional objects shown from carefully chosen perspectives, won first place at the Best Illusion of the Year Contest in 2010, 2013, 2018,and 2020 and second place in 2015 and 2016.

Education and career Sugihara earned bachelor's, master's, and doctoral degrees in mathematical engineering from the University of Tokyo in 1971, 1973, and 1980 respectively. From 1973 to 1981 he worked as a researcher at the Ministry of International Trade and Industry. He then became an associate professor in the Department of Information and Computer Engineering at Nagoya University in 1981, and moved back to the Department of Mathematical Engineering and Information Physics at the University of Tokyo in 1986. Since 2009 he has been a professor at Meiji University.

Illusions Five of Sugihara's illusions have won awards at the annual Best Illusion of the Year Contest:

In 2010, his illusion "Impossible Motion: Magnet Slopes" won first place in the contest. This illusion uses forced perspective to show marbles seemingly rolling up ramps. In 2013 he won first place again (with Jun Ono and Akiyasu Tomoeda) for "Rotation Generated by Translation", an illusion that uses Moiré patterns to create the appearance of rotation from objects moving only by translation. In 2015 his "Ambiguous Garage Roof" won second place. The illusion appears to show a convex roof surface that is reflected in a mirror to a corrugated zig-zag shape. Neither of these appearances accurately describes the true shape of the roof. In 2016 he won second place again for "Ambiguous Cylinder Illusion", which shows a stack of cylinders that from one point of view appear to have a circular cross-section, and from another point of view appear rectangular. In 2018 he won his first place for his "Triply Ambiguous Object", which shows a rectangular object with three different interpretations when seen from three special viewpoints. In 2020 he won his first place for his "3D Schroeder Staircase". His interest in illusions stems from his research in the 1980s on automating the analysis of perspective drawings, which he published in the 1986 MIT Press book Machine Interpretation of Line Drawings. When he asked his computer system to interpret impossible objects such as the ones in the art of M. C. Escher, he discovered that they could be interpreted as drawings of real objects with unexpected shapes.

Other research Sugihara's research also includes the study of Voronoi diagrams. With three co-authors: Atsuyuki Okabe, Barry Boots, and Sung Nok Chiu, he wrote Spatial Tessellations: Concepts and Applications of Voronoi Diagrams (Wiley, 1994; 2nd ed., 2009).

References

External links Home page Anomalous Objects – a selection of still images published by Sugihara Optical Illusionist - a video produced by Meiji University featuring an interview with Sugihara showcasing some of his works

Worked examples

Example 1 — a first encounter with Kokichi Sugihara

Start with the simplest possible case. Write down what Kokichi Sugihara claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Kokichi Sugihara before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Kokichi Sugihara ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Kokichi Sugihara

In research: Kokichi Sugihara appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Kokichi Sugihara in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Kokichi Sugihara is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1948 births, Academic staff of Meiji University, Academic staff of Nagoya University, so understanding it makes those chapters shorter.
In everyday life: Look for Kokichi Sugihara outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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How to study Kokichi Sugihara in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Kokichi Sugihara means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Kokichi Sugihara out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Kokichi Sugihara in simple terms?

Why does Kokichi Sugihara matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Kokichi Sugihara?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Kokichi Sugihara.