The problem with quantum mechanics, or at least the reason even physicists don’t understand it, isn’t that it paints an unfamiliar picture of reality. It isn’t difficult to accept that the world of fundamental particles, of which we have no direct experience, is radically different to the world we perceive.
The problem is instead that it doesn’t portray the hinterlands between these two worlds, offering no clear outline of how one emerges from the other. As a result, a century after it was committed to canvas, we still don’t know what this scientific masterpiece means for our understanding of reality.
This article is part of a special series celebrating the 100th anniversary of the birth of quantum theory. Read more here.
We aren’t short of ideas. Which of them you prefer is largely a matter of taste, or at least philosophical consideration, because they don’t tend to submit to experimental testing. As physicist N. David Mermin has joked: “New interpretations appear every year. None ever disappear.”
In the past decade, however, something has begun to shift. One new twist on quantum theory is the first to make explicit observational predictions, raising hopes of empirical progress. Another, meanwhile, has gathered momentum because it can seemingly solve several perplexing quantum mysteries in one fell swoop – even if it implies that there is no such thing as objective reality after all.
More promising still, physicists have even begun to feel out new ways to test the validity of such assumptions. As they turn mind-boggling thought experiments into real-world tests, we might finally be able to make progress on the question of what…
