Originally posted by sonhouseI think a spiral has to revolve around a point and get larger at the same time.
It appears to be a spiral because it IS a spiral. I think you are saying it should be a TURNING spiral or something.
This is not a spiral, it is a set of circles inside other circles.
Originally posted by sonhouseIf you dont believe it is not a spiral, take your finger and place it on the "spiral" Then follow it down to the center...You will realize it is just concentric circles.
It appears to be a spiral because it IS a spiral. I think you are saying it should be a TURNING spiral or something.
The effects that I see that make it look like a spiral.
1) Alternating black/white and light/dark blue squares from one concentric circle to the next are alternating, so the squares themselves (e.g. just the black squares) DO form a spiral toward the center.
2) the diamond pattern at the corners of the black/white squares make it appear that each square is "slanted" in the direction of the apparent spiral. Therefore, the entire circle appears to be nearing the center as you follow it around.
Originally posted by joneschrIt may still have something to do with depth perception. Many of the clues for depth are not binocular (.e.g, occlusion); they can still operate with just one eye open. That's why the world does not go flat when you close one eye.
I thought perhaps it had something to do with depth perception - but closing 1 eye doesn't trick it in anyway.