Science
Basic Books
20/03/2018
384
The untold story of the heretical thinkers who dared to question the nature of our quantum universe Every physicist agrees quantum mechanics is among humanity’s finest scientific achievements. But ask what it means, and the result will be a brawl. For a century, most physicists have followed Niels Bohr’s Copenhagen interpretation and dismissed questions about the reality underlying quantum physics as meaningless. A mishmash of solipsism and poor reasoning, Copenhagen endured, as Bohr’s students vigorously protected his legacy, and the physics community favored practical experiments over philosophical arguments. As a result, questioning the status quo long meant professional ruin. And yet, from the 1920s to today, physicists like John Bell, David Bohm, and Hugh Everett persisted in seeking the true meaning of quantum mechanics. What Is Real? is the gripping story of this battle of ideas and the courageous scientists who dared to stand up for truth.
Is quantum mechanics complete?
Perhaps not. Adam Becker’s “What is Real?” makes a case for alternative theories to counter the hegemony of the Copenhagen Interpretation.
The world described by quantum mechanics is a strange one. To fully appreciate its strangeness, picture this in your mind: Imagine a ball rolling down a track at a speed of 1 meter per second. Classical physics tells us this: if we can measure the position and velocity of the ball at this time, we can predict the position and velocity of the said ball at different points in the future.
Even if no one is looking at the ball, everyone would agree that the ball has definite properties. If our measurements do not disturb the system, we can measure the properties without changing anything about the ball at all. All that changes is our knowledge. We now know something additional about the world that we previously did not know.
Now, imagine that the ball is shrunk to the size of an electron. The Copenhagen Interpretation of quantum mechanics tells us that the electron does not have any definite properties before the act of measurement. In fact, it exists in a superposition of all possible values until someone comes along to measure it. When that happens, the ‘wavefunction’ of the system collapses, giving rise to a singular definite value. It is not just our knowledge of the world that changes. By choosing to take a measurement, we are changing something deeply fundamental about the external world.
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