It's been close to a century since we established how quantum mechanics "works," and we still don't know what it really means — and that, says cosmologist Sean Carroll in the video up top, may make QM the most embarrassing subject in all of modern physics.
What's embarrassing, says Carroll, isn't that there remain unanswered questions about quantum mechanics, or that there's debate within the physics community regarding its significance. In science, uncertainty, skepticism and deliberation participate in a powerfully deductive dialectic that enables us to rework our understanding of nature — to step back from what we think we know, re-assess our preconceived notions, and bring forth newer, more fully formed views of our Universe. This notion — that science advances not in spite of uncertainty, but because of it — is precisely why Stephen Hawking bet against the discovery of the Higgs Boson. In physics (as with pretty much any scientific field), unanswered questions and internal debate are, almost invariably, wellsprings of progress.