Science Matters

Gravity Waves

The existence of gravity waves, ripples in space-time, predicted by Einstein in his general theory of relativity, have apparently been confirmed, found imprinted on the cosmic microwave background. Gravity waves are evidence of inflation, the idea that the universe expanded rapidly less than a trillionth of a second after the Big Bang.

What is the shape of our Universe?
If the universe is open, shaped like a saddle, then it will expand forever.
If the universe is closed, curved like a sphere, it will eventually undergo a “Big Crunch.”
If the universe is geometrically flat, it may be infinite in size.
The diameter of the observable universe is estimated at about 93 billion light-years, putting the edge of the observable universe at 46-47 billion light-years away.

Gravity Probe

A 52-year-old project by NASA and Stanford University has concluded with the confirmation of two key gravity predictions made by Albert Einstein. Stanford's and NASA's Gravity Probe B satellite, launched April 20, 2004, used four ultra-precise gyroscopes to measure two key aspects of gravity in Einstein's general relativity theory, the geodetic effect (the warping of space-time around a gravitational body), and frame-dragging (the amount a spinning object pulls space and time along for the rotation).