Quantum mechanics

“We cannot make apparatuses arbitrarily big. ... We might need some extension of quantum mechanics.”

“Quantum mechanics was, and continues to be, revolutionary, primarily because it demands the introduction of radically new concepts to better describe the world. In addition we have argued that conceptual quantum revolutions in turn enable technological quantum revolutions.”

“… that what is proved, by impossibility proofs, is lack of imagination.”

“I am a Quantum Engineer, but on Sundays I Have Principles.”

“Quantum mechanics had never been wrong. And now we know that it will not be wrong even in these very tricky conditions.”

“I'm quite convinced of that: quantum theory is only a temporary expedient.”

“I hesitated to think it might be wrong, but I knew that it was rotten. That is to say, one has to find some decent way of expressing whatever truth there is in it.”

“For those who are not shocked when they first come across quantum theory cannot possibly have understood it.”

“The power of the new quantum mechanics in giving us a better understanding of events on an atomic scale is becoming increasingly evident. The structure of the helium atom, the existence of half-quantum numbers in band spectra, the continuous spatial distribution of photo-electrons, and the phenomenon of radioactive disintegration, to mention only a few examples, are achievements of the new theory which had baffled the old.”

“Already in 1948, observations... agreed with quantum mechanics, not with local realism.”

“For me, the important thing about quantum mechanics is the equations, the mathematics. If you want to understand quantum mechanics, just do the math. All the words that are spun around it don’t mean very much. It’s like playing the violin. If violinists were judged on how they spoke, it wouldn’t make much sense.”

“What quantum mechanics tells us, I believe, is surprising to say the least. It tells us that the basic components of objects – the particles, electrons, quarks etc. – cannot be thought of as "self-existent". The reality that they, and hence all objects, are components of is merely "empirical reality".”

“...the "paradox" is only a conflict between reality and your feeling of what reality "ought to be."”

“Quantum theory was split up into dialects. Different people describe the same experiences in remarkably different languages. This is confusing even to physicists.”

“Many educators, and even politicians, have been firmly convinced that "free will" is not compatible with Newtonian physics, but very much so with quantum theory. They have been convinced also that it is desirable that the citizen should believe in free will, and they have exerted a certain influence in favor of the indeterministic formulation of subatomic physics. What they have in mind is certainly a sociological purpose of science, whatever the technological purposes may be.”

“Quantum mechanics, that mysterious, confusing discipline, which none of us really understands but which we know how to use. It works perfectly, as far as we can tell, in describing physical reality, but it is a ‘counter-intuitive discipline’, as social scientists would say. Quantum mechanics is not a theory, but rather a framework, within which we believe any correct theory must fit.”

“Einstein was confused, not the quantum theory.”

“My attitude — I would paraphrase Goering—is that when I hear of Schrödinger's cat, I reach for my gun.”

“Physicists do not believe quantum mechanics because it explains the world, but because it predicts the outcome of experiments with almost miraculous accuracy. Theorists kept predicting new particles and other phenomena, and experiments kept bearing out those predictions.”

“Erwin with his psi can do Just what does psi really mean?”

“It is often stated that of all the theories proposed in this century, the silliest is quantum theory. In fact, some say that the only thing that quantum theory has going for it is that it is unquestionably correct.”

“Quantum mechanics fascinates me. It describes a wide variety of phenomena based on very few assumptions. It starts with a framework so unlike the differential equations of classical physics, yet it contains classical physics within it. It provides quantitative predictions for many physical situations, and these predictions agree with experiments. In short, quantum mechanics is the ultimate basis, today, by which we understand the physical world.”

“Planck ...devised his quanta theory, according to which the exchange of energy between the matter and the ether—or rather between ordinary matter and the small resonators whose vibrations furnish the light of incandescent matter—can take place only intermittently. A resonator can not gain energy or lose it in a continuous manner. It can not gain a fraction of a quantum; it must acquire a whole quantum or none at all.”

“Ask anyone today working on foundational questions in quantum theory and you are likely to hear that there is still no consensus on many of these questions—all the while, of course, everybody seems to be in perfect agreement on how to apply the quantum formalism when it comes to making experimental predictions.”

“If we really want to understand quantum mechanics, the goal should be more about letting go of our biases and embracing what the Universe tells us about itself. Instead, Carroll regressively campaigns for the opposite in teasing his upcoming new book. Unsurprisingly, most physicists are underwhelmed.”

“The inner mysteries of quantum mechanics require a willingness to extend one’s mental processes into a strange world of phantom possibilities, endlessly branching into more and more abstruse chains of coupled logical networks, endlessly extending themselves forward and even backwards in time.”

“... was my first lesson in quantum mechanics, and in a very real sense my last, since the rest is mere technique, which can be learnt from books.”

“My own conclusion is that today there is no interpretation of quantum mechanics that does not have serious flaws. This view is not universally shared. Indeed, many physicists are satisfied with their own interpretation of quantum mechanics. But different physicists are satisfied with different interpretations. In my view, we ought to take seriously the possibility of finding some more satisfactory other theory, to which quantum mechanics is only a good approximation.”

“For a zeroth slogan about quantum mechanics, I’ve chosenWhat’s hard to understand is classical mechanics, not quantum mechanics.”

“The world is not as real as we think.… My personal opinion is that the world is even weirder than what quantum physics tells us.”