Black Holes, Wormholes And Time Machines By Jim Al-Khalili

For the Science Reader project, I read Black Holes, Wormholes, and Time Machines by Jim Al-Khalili. Interested in time travel and the secrets of space, I chose this book with hopes of better understanding our universe.
Starting with black holes, Khalili describes the creation of one. I found that a black hole is what remains when a massive star dies. Because stars are so massive and made out of gas, there is an intense gravitational field that is always trying to collapse the star. As the star dies, the nuclear fusion reactions stop because the fuel for these reactions gets burned up. At the same time, the star's gravity pulls material inward and compresses the core. As the core compresses, it heats up and eventually creates a supernova explosion in which the material and radiation blasts out into space. What remains is the highly compressed and extremely massive core. The core's gravity is so strong that even light cannot escape. This object is now a black hole and literally cannot be seen because of the absence of light. Because the core's gravity is so strong, the core sinks through the fabric of space-time, creating a hole in space-time. The core becomes the central part of the black hole called the singularity. The opening of the hole is called the event horizon. Khalili describes that there are two different kinds of black holes:
The Schwarzschild black hole is the simplest black hole, in which the core does not rotate. This type of black hole only has a singularity and an event horizon.
The Kerr black hole, which is the most common form, rotates because the star from which it was formed was rotating. When the rotating star collapses, the core continues to rotate, and this carried over to the black hole. The Kerr black hole...

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... succeed, what are the consequences of such freedom? Will we get trapped in a plethora of paradoxes and multiple universes that will destroy the fabric of the universe? Einstein said that nothing travels faster than the speed of light, but Khalili negates this statement, using the behavior of entangled particles to counter Einstein.
Until recently, theorists believed that wormholes could exist for only an instant of time, and anyone trying to pass through would run into a singularity. But Khalili shows the reader that more recent calculations show that a truly advanced civilization might be able to make wormholes work. By using something physicists call “exotic matter,” which has a negative energy, the civilization could prevent a wormhole from collapsing on itself. Perhaps someday in the far future, wormholes will become a useful asset in universal transportation.