"Hearst Magazines and Yahoo may earn commission or revenue on some items through the links below." A new paper suggests that time can actually flow forward and backward. Microscopic systems can ...

Ultrasonic flow meters are non-invasive devices that use acoustic vibrations to determine the flow rate of a liquid. There are two types of ultrasonic flow meters – Doppler and transit time. Both ...

Flow, as famously described and investigated by Mihaly Csikszentmihalyi, is a mental state characterized by deep absorption during challenging activities. It is a state of optimal experience that can ...