One of the dramatic peaks of the Empire Strikes Back was the freezing of Han Solo in Carbonite to be delivered to Jabba the Hutt. Even though this process was futuristic, it wasn’t considered “safe” – there was still risk (great for the story). But is it real?
Though carbonite seems like a biologic preservation material it is thematically a cryogenic chamber.
Freezing humans is an ongoing field of study. Cryonics looks at the ability to freeze animals / humans. The most exotic use cases are for long-range space travel (*cough* Mars) and for health reasons. As of 2013, 270 people have been cryogenically frozen. In the U.S., it is required that bodies can only be frozen after they have been pronounced dead.
Cryogenics is a pretty well-worn science fiction tool. In most cases, it is the premise for time travel into the future. The show Futurama used it. So did a great episode of Star Trek: The Next Generation.
The technical process is both simple and complex. We can physically freeze a body without much trouble. But Dr. Kaku gives some insight into some of the challenges.
Bacteria, by contrast are much more durable than more complex life. Bacterial have been found naturally in the north pole that had been frozen for millenia but were revived in mere moments. In fact, bacteria are routinely freeze-dried by bacterial researchers. It is one of the primary reasons we can so easily work with bacterial life in creating bacteria-driven industrial processes or study genomic sequences. The implications of freezing bacteria have been no less than a revolution in health care – industrial biotechnology.