Warp drives are a way of getting around the universe at a speed that is greater than the speed of light(3 x 108 m/s). Unfortunately, there is a speed limit for bodies travelling through space. The speed of light. However, space itself can bend and stretch without respect to any craft travelling in it. This is physically possible but requires a lot of materials that we don't really know how to harness, yet. If you want to find out more, do take a look at the video below. Also, there is a video by MIT+K12 on Khan academy, here.
Simply put, a neutron star is the leftover core of a dead star. It gets its name 'neutron' from the fact that the protons and electrons in each atom in the core combine to form neutrons. This also produces some of the densest matter discovered so far. Typical neutron stars have a mass of up to three solar masses (around 5,967,000,000,000,000,000,000,000,000 tn), which is crammed into a sphere with a radius of approximately ten kilometres (our sun's radius measures 695,700 km !). Therefore the material can weigh upto 6 billion tonnes a teaspoon. At this point most feel that, "okay, it's super dense, is that all?". No, its not. Our Earth obtained most of th heavy elements such as gold, silver, platinum when two neutron stars collide. This occurs when two neighbouring stars die together