Who was the first to propose that the universe is expanding? The very first time they heard a consistent, low noise on their detectors they discovered that it was (mostly) not the CMBR. Physicist Lene...Who was the first to propose that the universe is expanding? The very first time they heard a consistent, low noise on their detectors they discovered that it was (mostly) not the CMBR. Physicist Lene Hau first slowed a beam of light to 17m/s using a very cold, dilute gas of bosons. Think of two theories that you use in your every day life. (For example, when we wash our hands, we do so because of the germ theory of disease!)
