Scientists achieve X-ray vision with safe, visible light

If you think X-rays and other forms of radiation have a monopoly on penetrating opaque objects, visible light begs to differ. It actually can pass through things like paint and human tissue, which has powerful implications for medical research and other fields. Regular lightwaves could one day replace X-rays or even allow scientists to remove tumors with lasers instead of risky surgery. The problem is, such light is either absorbed or scattered once it passes through non-transparent items...

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