Image: Goñi Montes
In Brief
- Quantum mechanics used to be described as a theory of limits, implying that our observations are unavoidably uncertain, that randomness rules the world, and that the theory itself is too weird to master and forces us to abandon the very idea that there is a world out there that science could describe.
- Those misconceptions are rooted in philosophical doctrines, such as logical positivism, that were popular during the period when physicists developed and honed the theory.
- In truth, quantum mechanics imposes no significant limits. The quantum world has a richness and intricacy that allows new practical technologies and kinds of knowledge.
Late in the 19th century an unknown artist depicted a traveler who reaches the horizon, where the sky meets the ground. Kneeling in a stylized terrestrial landscape, he pokes his head through the firmament to experience the unknown [see illustration on page 89]. The image, known as the Flammarion engraving, illustrates the human quest for knowledge. Two possible interpretations of the visual metaphor correspond to two sharply different conceptions of knowledge.
Either it depicts an imaginary barrier that, in reality, science can always pass through, or it shows a real barrier that we can penetrate only in our imagination. By the latter reading, the artist is saying that we are imprisoned inside a finite bubble of familiar objects and events. We may expect to understand the world of direct experience, but the infinity outside is inaccessible to exploration and to explanation. Does science continually transcend the familiar and reveal new horizons, or does it show us that our prison is inescapable—teaching us a lesson in bounded knowledge and unbounded humility?
This article was originally published with the title Beyond the Quantum Horizon.
Already a Digital subscriber? Sign-in Now
If your institution has site license access, enter here.
See what we're tweeting about
5 Comments
Add CommentThis is an enjoyable article. I was taught quantum mechanics in the nineties and yes, from time to time we got the "quantum mechanics is a theory that cannot be understood" remark and the "you cannot ask that question" answer. I agree with the authors that although quantum mechanics seem to impose limits to what we can know about a system in classical terms, e.g. the exact positions and impulses of each of an ensemble of particles, this may not be the whole truth. In this respect, it seems important to remember that the quantum mechanical wave function of a system is inherently deterministic: known at a certain time t, the time dependent wave function describes the state of the system at all other times. It is more the measurement of certain parameters that prevents us from knowing certain other parameters with absolute precision due to the uncertainty principle. As the authors already suggested, the key to use quantum mechanics for the benefit of humankind is a carefull selection of parameters to measure and manipulate.
Reply | Report Abuse | Link to thisDoes this mean we're uncertain about the uncertainty principle? Now I'm confused...or am I?
Reply | Report Abuse | Link to thisI want to share the printed article ("Beyond the Quantum Horizon") with my friends/colleagues. I really like the graphic, the Flammarion Engraving. The "impossible" logic gates and "beyond bad philosophy" sections provided me with some a good discussion material. There are many applications in my field that I am looking forward to exploring. Thanks.
Reply | Report Abuse | Link to thisThe article is journalism gem.
Reply | Report Abuse | Link to thisDo read it several time,something new pops up every time..
Page 74 3.colum,lower part,line:"A quantum computer could do so quickly"
If you read the text,before that sentence,you know the article is NUKE.
My own thinking:Discovery Channel had a docu named "Traveling with lighspeed through space"...
The docu spells out:if two cars travel through space, both doing 8o km/hour,towards another,they will meet...
the same at lightspeed:no cars meet....
Now...read the line from the article again....
'He went on to explain that when his famous equation describes different histories of a particle, those are "not alternatives but all really happen simultaneously."' Not difficult to understand when that same reasoning applies to each of us. The histories of our ancestors are in our genes. but my father had a different nationality (and history) from my mother, as did my grandparents, and so on.
Reply | Report Abuse | Link to thisOn another aspect, I did high school physics a long time ago and learnt about the Bohr atom, then there was a vague reference to quantum stuff, that the electron's position was probabilistic and could extend out to infinity. But no model was given to visualize this, so I had to think up one myself. My model has the atom surrounded by a big ball of jelly-like substance (which can be the electric field). Then imagine you take a pinch of this jelly, pull it back and let it go. The pinch point bounces around, and being friction-free jelly goes on forever, as a wave moving around the nucleus. Stretch it back far enough (i.e. inject energy) and when it bounces back a blob breaks off and shoots away, thus having the property of a particle.