Abstract: I welcome you to the fourth issue of the IEEE Communications Surveys and Tutorials in 2021. This issue includes 23 papers covering different aspects of communication networks. In particular, ...

Can you chip in? As an independent nonprofit, the Internet Archive is fighting for universal access to quality information. We build and maintain all our own systems, but we don’t charge for access, ...

Normally, when liquids solidify, their molecules become locked in place, making it much harder for ions to move and leading ...

Liquids and solutions are complex environments—think, for example, of sugar dissolving in water, where each sugar molecule ...

Using the world’s most powerful X-ray laser, scientists have filmed atoms performing an eternal quantum dance that never ...