General relativity tells us this photon would follow a classical path that aligns with the curves and contours of space-time from ... a "holograph — with no gravity. In this projection, the ...

While no gravity in space is, let’s be honest, pretty cool, it comes with some downsides. Without the constant weight of the world on their shoulders, astronauts’ bones and muscles can grow weak.

Lower gravity. Higher radiation. No ER access. These are just a few of the challenges that humans face in outer space. Emily and Regina talk to a NASA astronaut (and astronaut scientist ...