THE ARTICLE

Scientists in the USA say they are a step closer to developing materials that could make people invisible. Researchers at the University of California have found a way to cloak humans and objects using special materials that redirect light around things. The findings, led by Professor Xiang Zhang, were published in the journals ‘Nature’ and ‘Science’. Zhang works at the Nanoscale Science and Engineering Centre at the university. His team developed a set of artificial “meta-materials” on a microscopic scale that is measured in billionths of a metre. The researchers said the special “fishnet structure” of the nano-sized objects do not absorb or reflect light, which makes them seem invisible. They compared the light to “water flowing around a rock".

The new discovery is a huge step forward from earlier technology that only allowed the concealing of two-dimensional objects. In the future, scientists could make “invisibility clothing” to hide people and large objects. However, scientists are still a long way from designing and manufacturing invisibility cloaks. The U.S. military is extremely interested in developing this idea to bring the technology to the battlefield. The U.S. Army Research Office funded part of Dr. Zhang’s research. The technology could also lead to more powerful microscopes that are able to look more closely at living cells and even tinier objects. This means scientists could look at how viruses are formed and how they grow.

WARM-UPS

1. SCIENCE:Walk around the class and talk to other students about science. Change partners often. After you finish, sit with your partner(s) and share your findings.

2. CHAT: In pairs / groups, decide which of these topics or words from the article are most interesting and which are most boring.

Have a chat about the topics you liked. Change topics and partners frequently.

3. INVISIBILITY:Would you like to be invisible? Look at the situations below. With your partner(s), write ideas about the benefits of being invisible in these situations. Change partners and share your ideas.

4. BEING INVISIBLE:Students A strongly believe being invisible will only be used in good ways; Students B strongly believe being invisible will be used in bad ways. Change partners again and talk about your roles and conversations.

5. STEPS CLOSER:With your partner(s), put a year, decade, century, or ‘never’ next to these possible future developments. Discuss which ones you would like to see.

6. LIGHT:Spend one minute writing down all of the different words you associate with the word ‘light’. Share your words with your partner(s) and talk about them. Together, put the words into different categories.