## Why does this spinning arrow ALWAYS point right? Mathematician’s incredible optical illusion leaves the internet baffled

• It is the creation of Professor Kokichi Sugihara at Meiji University in Tokyo
• Professor Sugihara has a long history of designing mind-bending objects
• His latest object has been carefully crafted so the arrow only points right
• This duplicity can only be discerned when viewing the device from above
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A spinning arrow that always points right has been created as part of an incredible optical illusion taking the internet by storm.

The trick of the eye – which is the latest in a long line designed by a Japanese mathematician – appears at first glance to be a simple white arrow

Looks can be deceiving, however, as the object – mounted on a wooden stand – has been carefully crafted to achieve its mind-bending effect.

This duplicity can only be seen when viewing the device from above, revealing its secret.

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The illusion is the brainchild of Professor Kokichi Sugihara, doctor of engineering at Meiji University in Tokyo.

Professor Sugihara is famous for building 3D optical illusions that cause viewers to question the laws of physics and even after the hoax is revealed they can still see the same visual trick taking place.

The illusion is featured in video footage posted to the Instagram page Physicsfun, where it had been viewed 368,452 times at the time of publication.

In the description, its author writes: ‘Spin this arrow 180 degrees and it still points to the right – only in a mirror will it point left, and only to the left.

‘A clever combination of reflection, perspective, and viewing angle produce this striking illusion.’

This mirror image provides a clue to the design of the spinning arrow, which is responsible for it’s seemingly magical properties.

A spinning arrow that always points right has been created as part of an incredible optical illusion taking the internet by storm. The trick of the eye appears at first glance to be a simple white arrow, mounted on a wooden stand

Right Pointing Arrow: spin this arrow 180 degrees and it still points to the right- only in a mirror will it point left (and only to the left). Another incredible ambiguous object illusion by mathematician Kokichi Sugihara of Meiji University in Japan, the inventor of this illusion and art form. A clever combination of reflection, perspective, and viewing angle produce this striking illusion. ➡️ Follow the link in my profile for info about where to get this illusion arrow and other amazing items featured here on @physicsfun #illusion #ambiguouscylinderillusion #ambiguouscylinder #geometry #mirrorreflection #physics #ambiguousobject #kokichisugihara #physicstoy #math #mathtoy #mathstoy #optics #opticalillusion #3dprinting #perspective #science #scienceisawesome

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In the latter part of the clip, the arrow is tilted up to reveal its true shape – an oblong with two pointed ends, with multiple upward and downward gradients.

It is this strange symmetrical layout, a characteristic feature of Professor Sugihara’s work, that achieves the illusion.

When viewed from above, the arrow object is perfectly symmetrical, but from the perspective it is first viewed from in the video, the alternating undulations visible from above make it appear as if it points in one direction.

Your brain then tries to match this shape to something familiar, filling in the gaps in your perception with the most obvious candidate – an arrow.

The illusion is the brainchild of Professor Kokichi Sugihara, doctor of engineering at Meiji University in Tokyo. Looks can be deceiving, as the object has been carefully crafted to achieve its mind-bending effect

This duplicity can only be discerned when viewing the device from above. The object’s true shape is an oblong with two pointed ends, with multiple upward and downward gradients. It is this strange symmetrical layout that achieves the illusion

### HOW DOES THE RIGHT SPINNING ARROW ILLUSION WORK?

A spinning arrow that always points right has been created as part of an incredible optical illusion taking the internet by storm.

The trick of the eye, which is the latest in a long line designed by a Japanese mathematician, appears at first glance to be a simple white arrow, mounted on a wooden stand.

Looks can be deceiving, however, as the object has been carefully crafted to achieve its mind-bending effect, and this duplicity can only be discerned when viewing the device from above.

When viewed from above, the arrow object is perfectly symmetrical, but from the perspective it is first seen, the alternating undulations visible from above make it appear as if it points in one direction.

Your brain then tries to match this shape to something familiar, filling in the gaps in your perception with the most obvious candidate – an arrow.

The illusion was particularly well received on Reddit, where it perplexed participants of a forum dedicated to quirky and interesting finds from the online world.

Asperi said: ‘Damn it. This one is really messing with my head.’

One anonymous user said: ‘You can put one right in my hand and I still wouldn’t figure out how.’

ketchy_shuby added: ‘When the mirror image appeared I could feel portions of my brain forming new folds.’

This is not the first time that the perception-altering illusions of Professor Sugihara have hit the headlines.

An illusion created using ‘ambiguous cylinders’ has been blowing the internet’s collective mind since it was posted online in 2016.

Professor Sugihara received second place at that year’s annual Illusion of the Year contest for his offering. In it, a set of plastic squares appear to be circular when placed in front of a mirror.

A video of the illusion was posted on Reddit and quickly got the attention of readers who were left bemused by its mind-bending optics.

The minute long clip shows six plastic squares fused together that, when placed in front of a mirror, appear to be shaped like circles. Then, the squares are rotated and appear to be shaped like circles, while the reflection flips and becomes square.

An illusion created using ‘ambiguous cylinders’ has been blowing the internet’s collective mind since it was posted online in 2016. In it, a set of plastic squares appear to be circular when placed in front of a mirror

A minute long clip posted about the illusion shows six plastic squares fused together that, when placed in front of a mirror, appear to be shaped like circles. Then, the squares are rotated and appear to be shaped like circles, while the reflection flips and becomes square

Another set is then introduced, this time with four squares, which appear in the mirror to be interlocked circles. Gradually, more and more 3D shapes are brought in, which all illustrate the same mind-bending illusion.

Staff at 3D printing company Make Anything were the first to reveal the magic behind the mystery, ‘reverse engineering’ the illusion to created a model using a printer.

They revealed that the ‘true shape’ of the pieces was an exact blend between a circle and a square, with one side curved upwards, while the other side is sloped downwards.

The different heights of the sides ‘corrects’ the fact that the sides are different shapes, which means that it blends back into a square or back into a circle when the true shape is right in between.

Another of Professor Sugihara’s illusions involves a tiny paper house with a roof that’s more than meets the eye.

When three balls are placed on it and do not roll down its sides, you might think its creator has found a way to defy both geometry and gravity.

Another of Professor Sugihara’s illusions involves a tiny paper house with a roof that’s more than meets the eye. Professor Sugihara creates these kind of works using computer software that uses two-dimensional line drawings to design three-dimensional objects

When three balls are placed on its roof and do not roll down its sides, one might think its creator has found a way to defy both geometry and gravity

What’s actually happening is your brain assumes the structure is constructed with an upward sloping roof, when in fact it is sloping downward

But what’s actually happening is your brain assumes the structure is constructed with an upward sloping roof, when in fact it is sloping downward.

This is revealed once the house’s true form is shown, which can only be seen from a particular angle.

Professor Sugihara creates these kind of works using computer software that uses two-dimensional line drawings to design three-dimensional objects.

In another trick involving apparently defying gravity, Professor Sugihara’s optical illusion shows a four-way ramp structure and some wooden balls that appear to travel straight up its slopes and not down.

The mathematician said the brain is easily fooled into thinking the ramps are facing the opposite way to how they actually are.

In another trick involving apparently defying gravity, Professor Sugihara’s optical illusion shows a four-way ramp structure and some wooden balls that appear to travel straight up its slopes and not down

The mathematician said the brain is easily fooled into thinking the ramps are facing the opposite way to how they actually are. ‘Because the images do not contain information about depth, the brain must guess by entering additional information such as squareness or symmetry,’ Professor Sugihara said

‘Because the images do not contain information about depth, the brain must guess by entering additional information such as squareness or symmetry,’ Professor Sugihara said.

‘On the other hand, there are infinite ways to interpret an image without this process would have no way to understand them.’

Another, called Folding Ladder, shows a chopstick passing through different windows of a ladder-like structure.

The configurations seem impossible – unless the stick could bend – because each row of windows appear flat. But when the structure is shown from behind, it isn’t flat at all.

According to Nautillus, Professor Sugihara sketched the ladder and then put the drawing through his program. He chose the three-dimensional interpretation that was most different from the natural human interpretation, which is why the trick works so well.

Another, called Folding Ladder, shows a chopstick passing through different windows of a ladder-like structure. The configurations seem impossible – unless the stick could bend

Because each row of windows appear flat, the illusion appears impossible, but when the structure is shown from behind, it isn’t flat at all.

Professor Sugihara sketched the ladder and then put the drawing through his program. He chose the three-dimensional interpretation that was most different from the natural human interpretation, which is why the trick works so well