how do scientists confirm things like the universe is expanding rather than contracting?
In: Physics
It’s called red shift and blue shift. The easiest was to explain it is the sound difference when a cop car is coming towards you vs away from you the siren gets higher pitched and speed up as the car is lvokg towards you, that’s called blue shift. When the cop car is moving away from you, the sound lowers in pitch and gets slower. That’s red shift.
We look at the light from stars and galaxies and look for either red shift or blue shift. If it’s red shift, they’re getting farther away and the universe is expanding. If they see blue shift, the universe is contracting because those stars and galaxies are getting close to us.
Latest Answers