Important Notice: Our web hosting provider recently started charging us for additional visits, which was unexpected. In response, we're seeking donations. Depending on the situation, we may explore different monetization options for our Community and Expert Contributors. It's crucial to provide more returns for their expertise and offer more Expert Validated Answers or AI Validated Answers. Learn more about our hosting issue here.
When a beam of light enters a material at an angle, it is bent by an amount determined by the index-of-refraction of the material. All known materials have a positive index-of-refraction; however, it is possible to make an artificial metamaterial that has a negative index-of-refraction. A beam of light will be bent the opposite way in this metamaterial.
