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It is now possible to make clones, or exact genetic copies, of sheep, cows, goats, mice and, probably, humans. This opens the way towards the production of replacement body parts from adult cells.
We know how many drugs of abuse – cocaine, heroin and nicotine – work, but less about how they lead to addiction. Studies of the brain-learning systems concerned are addressing the causes of addiction, with the intent of developing better treatments.
The inventor of the term ‘black hole’, John Wheeler, has a gift for memorable phrases. ‘Getting its from bits’ is another of his creations. It refers not to an object, but to a vision of a world derived from pure logic and mathematics. That vision has to a remarkable extent been embodied in modern physics — here is a progress report.