In Quantum Mechanics Quotes & Sayings

There is a mathematical underpinning that you must first acquire, mastery of each mathematical subdiscipline leading you to the threshold of the next. In turn you must learn arithmetic, Euclidian geometry, high school algebra, differential and integral calculus, ordinary and partial differential equations, vector calculus, certain special functions of mathematical physics, matrix algebra, and group theory. For most physics students, this might occupy them from, say, third grade to early graduate school - roughly 15 years. Such a course of study does not actually involve learning any quantum mechanics, but merely establishing the mathematical framework required to approach it deeply. — Carl Sagan

Another very good test some readers may want to look up, which we do not have space to describe here, is the Casimir effect, where forces between metal plates in empty space are modified by the presence of virtual particles.

Thus virtual particles are indeed real and have observable effects that physicists have devised ways of measuring. Their properties and consequences are well established and well understood consequences of quantum mechanics. — Gordon L. Kane

Yet, at the quantum level, NO part of the body lives apart from the rest. There are no wires holding together the molecules of your arteries, just as there are no visible connections binding together the stars in a galaxy. Yet arteries and galaxies are both securely held together, in a seamless, perfect design. The invisible bonds that you cannot examine under a microscope are quantum in nature; without this "hidden physiology," your visible physiology could not exist. It would never have been more than a random collection of molecules. — Deepak Chopra

People don't learn science in movies. You don't go to the movies thinking, 'I hope I learn some quantum mechanics this afternoon.' But on the other hand, movies are instrumental and influential in getting young people interested in science. — Seth Shostak

It seems sensible to discard all hope of observing hitherto unobservable quantities, such as the position and period of the electron ... Instead it seems more reasonable to try to establish a theoretical quantum mechanics, analogous to classical mechanics, but in which only relations between observable quantities occur. — Werner Heisenberg

Quantum mechanics is just completely strange and counterintuitive. We can't believe that things can be here [in one place] and there [in another place] at the same time. And yet that's a fundamental piece of quantum mechanics. So then the question is, life is dealing us weird lemons, can we make some weird lemonade from this? — Seth Lloyd

Einstein's paper on the photoelectric effect was the work for which he ultimately won the Nobel Prize. It was published in 1905, and Einstein has another paper in the very same journal where it appeared - his other paper was the one that formulated the special theory of relativity. That's what it was like to be Einstein in 1905; you publish a groundbreaking paper that helps lay the foundation of quantum mechanics, and for which you later win the Nobel Prize, but it's only the second most important paper that you publish in that issue of the journal. — Sean Carroll

Quantum theory provides us with a striking illustration of the fact that we can fully understand a connection though we can only speak of it in images and parables. — Werner Heisenberg

The mechanism by which quantum mechanics injects an element of chance into the operation of the universe is called "decoherence" (Gell-Mann and Hartle, 1994). Decoherence effectively creates new bits of information, bits which previously did not exist. In other words, quantum mechanics, via decoherence, is constantly injecting new bits of information into the world. Every detail that we see around us, every vein on a leaf, every whorl on a fingerprint, every star in the sky, can be traced back to some bit that quantum mechanics created. Quantum bits program the universe. — Paul Davies

You create reality by looking at it, is what Quantum Mechanics suggests. This may sound outrageously magical. Quantum Mechanics or QM, is the physics of the microscopic world. It is a strange theory that took birth in the early 20th century and continues to dazzle scientists and philosophers today. So much so, that QM is regarded as the gateway to the world of consciousness, bringing science and spiritualty together. Science has entered domain of philosophy and consciousness/spirituality through Quantum Mechanics, making it a hot topic for debate among intellectuals from both scientific and philosophical domains. Some physicists even insist on making philosophy of physics! — Sharad Nalawade

Once you believe in quantum mechanics," I said, "it's hard to rule something out merely because it is impossible. — Ted Kosmatka

The Theory of Relativity confers an absolute meaning on a magnitude which in classical theory has only a relative significance: the velocity of light. The velocity of light is to the Theory of Relativity as the elementary quantum of action is to the Quantum Theory: it is its absolute core. — Max Planck

Bertrand Russell had given a talk on the then new quantum mechanics, of whose wonders he was most appreciative. He spoke hard and earnestly in the New Lecture Hall. And when he was done, Professor Whitehead, who presided, thanked him for his efforts, and not least for 'leaving the vast darkness of the subject unobscured'. — J. Robert Oppenheimer

I count Maxwell and Einstein, Eddington and Dirac, among "real" mathematicians. The great modern achievements of applied mathematics have been in relativity and quantum mechanics, and these subjects are at present at any rate, almost as "useless" as the theory of numbers. — G.H. Hardy

A gifted experimentalist, and theoretician, in the best Newtonian tradition ... His contributions to quantum measurements, and elucidative teachings on quantum mechanics, have not yet received the attention they deserve. — Willis Lamb

The birth of science as we know it arguably began with Isaac Newton's formulation of the laws of gravitation and motion. It is no exaggeration to say that physics was reborn in the early 20th-century with the twin revolutions of quantum mechanics and the theory of relativity. — Paul Davies

If you have nothing in quantum mechanics, you will always have something. — Lawrence M. Krauss

Perhaps the main basis for the claim that quantum mechanics is weird is the existence of what Einstein called 'spooky action at a distance'. These effects are not only 'spooky' but are also absolutely impossible to achieve within the framework of classical physics. However, if the conception of the physical world is changed from one made out of tiny rock-like entities to a holistic global informational structure that represents tendencies to real events to occur, and in which the choice of which potentiality will be actualized in various places is in the hands of human agents, there is no spookiness about the occurring transfers of information. The postulated global informational structure called the quantum state of the universe is the 'spook' that does the job. But it does so in a completely specified and understandable way, and this renders it basically non-spooky. — Paul Davies

Unfortunately, most of the prevailing descriptions of quantum theory tend to emphasize puzzles and paradoxes in a way that makes philosophers, theologians, and even non-physicist scientists leery of actually using in any deep way the profound changes in our understanding of human beings in nature wrought by the quantum revolution. Yet, properly presented, quantum mechanics is thoroughly in line with our deep human intuitions. It is the 300 years of indoctrination with basically false ideas about how nature works that now makes puzzling a process that is completely in line with normal human intuition. — Paul Davies

No credible understanding of the natural world or our human existence - what I am going to call in this book a worldview - can ignore the basic insights of theories as key as evolution, relativity, and quantum mechanics. — Dalai Lama XIV

Should a priest reject relativity because it contains no authoritative exposition on the doctrine of the Trinity? Once you realize that the Bible does not purport to be a textbook of science, the old controversy between religion and science vanishes ... The doctrine of the Trinity is much more abstruse than anything in relativity or quantum mechanics; but, being necessary for salvation, the doctrine is stated in the Bible. If the theory of relativity had also been necessary for salvation, it would have been revealed to Saint Paul or to Moses. — Georges Lemaitre

There are a lot of mysteries about quantum mechanics, but they mostly arise in very detailed measurements in controlled settings. — Lisa Randall

I remember discussions with Bohr which went through many hours till very late at night and ended almost in despair; and when at the end of the discussion I went alone for a walk in the neighbouring park I repeated to myself again and again the question: Can nature possibly be so absurd as it seemed to us in these atomic experiments? — Werner Heisenberg

In the beginning there were only probabilities. The universe could only come into existence if someone observed it. It does not matter that the observers turned up several billion years later. The universe exists because we are aware of it. — Martin J. Rees

Quantum mechanics challenges this view by revealing, at least in certain circumstances, a capacity to transcend space; long-range quantum connections can bypass spatial separation. Two objects can be far apart in space, but as far as quantum mechanics is concerned, it's as if they're a single entity. — Brian Greene

Quantum mechanics provides us with an approximate, plausible, conjectural explanation of what actually is, or was, or may be taking place inside a cyclotron during a dark night in February. — Edward Abbey

It is difficult for me to believe that quantum mechanics, working very well for currently practical set-ups, will nevertheless fail badly with improvements in counter efficiency. — John Stewart Bell

'Participant' is the incontrovertible new concept given by quantum mechanics. It strikes down the 'observer' of classical theory, the man who stands safely behind the thick glass wall and watches what goes on without taking part. It can't be done, quantum mechanics says it ... May the universe in some sense be 'brought into being' by the participation of those who participate? — John Archibald Wheeler

The strength of the familiar electromagnetic force between two electrons, for example, is expressed in physics in terms of a constant known as the fine structure constant. The value of this constant, almost exactly 1/137, has puzzled many generations of physicists. A joke made about the famous English physicist Paul Dirac (1902-1984), one of the founders of quantum mechanics, says that upon arrival to heaven he was allowed to ask God one question. His question was: "Why 1/137? — Mario Livio

Quantum fluctuations are, at their root, completely a-causal, in the sense that cause and effect and ordering of events in time is not a part of how these fluctuations work. Because of this, there seem not to be any correlations built into these kinds of fluctuations because 'law' as we understand the term requires some kind of cause-and-effect structure to pre-exist. Quantum fluctuations can precede physical law, but it seems that the converse is not true. So in the big bang, the establishment of 'law' came after the event itself, but of course even the concept of time and causality may not have been quite the same back then as they are now. — Sten F. Odenwald

According to quantum mechanics, at the Planck scale length, instead of a gradually undulating geometry, there should be wild fluctuations and loops and handles of spacetime branching off, the sort of topography that the futuristic Ike encountered. General relativity cannot be used in such untamed territory. — Lisa Randall

The mind reels when we realize that, according to this interpretation of quantum mechanics, all possible worlds coexist with us. Although wormholes might be necessary to reach such alternate worlds, these quantum realities exist in the very same room that we live in. They coexist with us wherever we go. — Michio Kaku

Unlike determinism, fatalism does not proceed by contemplating the causal mechanics of the universe-the implications for human freedom of Newtonian physics or thermodynamics or quantum mechanics. Instead, the fatalist argues that his doctrine can be established by mere reflection on the logic of propositions about the future. In simplified form, a version of the argument might run as follows: If I fire my handgun, one second from now its barrel will be hot; if I do not fire, one second from now the barrel will not be hot; but the proposition one second from now the barrel will be hot is right now either true or false. If the proposition is true, then it is the case that I will fire the gun; if it's false, then it is the case that I won't. Either way, it's the state of affairs in the future that dictates what I will or won't do now. — David Foster Wallace

In the future, maybe quantum mechanics will teach us something equally chilling about exactly how we exist from moment to moment of what we like to think of as time. — Richard K. Morgan

If all people learned to think in the non Aristotelian manner of quantum mechanics, the world would change so radically that most of what we call "stupidity" and even a great deal of what we consider "insanity" might disappear, and the "intractable" problems of war, poverty and injustice would suddenly seem a great deal closer to solution. — Alfred Korzybski

The doctrine that the world is made up of objects whose existence is independent of human consciousness turns out to be in conflict with quantum mechanics and with facts established by experiment. — Bernard D'Espagnat

Relativity and quantum mechanics have demonstrated clearly that what you find out with instruments is true relative only to the instrument you're using, and where that instrument is located in space-time. So there is no vantage point from which 'real' reality can be seen; we're all looking from the point of view of our own reality tunnels. — Robert Anton Wilson

Quantum mechanics is weird. I don't understand it. Just live with it. You don't have to understand the nature of things in order to build cool devices. — Seth Lloyd

All the calculus, quantum mechanics and languages in the world are worthless pieces of information, if they are not brought to the service of the society. — Abhijit Naskar

A new concept of god: something not very different from the sum total of the physical laws of the universe; that is, gravitation plus quantum mechanics plus grand unified field theories plus a few other things equaled god. And by that all they meant was that here were a set of exquisitely powerful physical principles that seemed to explain a great deal that was otherwise inexplicable about the universe. Laws of nature ... that apply not just locally, not just in Glasgow, but far beyond: Edinburgh, Moscow ... Mars ... the center of the Milky Way, and out by the most distant quarters known. That the same laws of physics apply everywhere is quite remarkable. Certainly that represents a power greater than any of us. — Carl Sagan

Renormalization is just a stop-gap procedure. There must be some fundamental change in our ideas, probably a change just as fundamental as the passage from Bohr's orbit theory to quantum mechanics. When you get a number turning out to be infinite which ought to be finite, you should admit that there is something wrong with your equations, and not hope that you can get a good theory just by doctoring up that number. — Paul Dirac

She figured that the main problem in physics is physicists, that most of them are caught in a mind trap because they're so used to things being made of smaller things. So they instinctively believe that reality, at its most basic level, must be made up of and regulated by almost infinitely small elementary particles. — Rajnar Vajra

Thus it can be argued that quantum theory provides an opening for an idea of nature and of our role within it that is in general accord with certain religious concepts, but that, by contrast, is quite incompatible with the precepts of mechanistic deterministic classical physics. Thus the replacement of classical mechanics by quantum mechanics opens the door to religious possibilities that formerly were rationally excluded. — Paul Davies

String theory is the most developed theory with the capacity to unite general relativity and quantum mechanics in a consistent manner. I do believe the universe is consistent, and therefore I do believe that general relativity and quantum mechanics should be put together in a manner that makes sense. — Brian Greene

I shook my head. "After a while, quantum mechanics starts to affect your worldview." "What does this mean?" "The more research I did, the less I believed." "In quantum mechanics?" "No," I said. "In the world. — Ted Kosmatka

The development of quantum mechanics early in the twentieth century obliged physicists to change radically the concepts they used to describe the world. — Alain Aspect

Atoms are weird stuff, behaving like active agents rather than inert substances. They make unpredictable choices between alternative possibilities according to the laws of quantum mechanics. It appears that mind, as manifested by the capacity to make choices, is to some extent inherent in every atom. The universe is also weird, with its laws of nature that make it hospitable to the growth of mind. I do not make any clear distinction between mind and God. God is what mind becomes when it passes beyond the scale of our comprehension. — Freeman Dyson

The most important single thing about string theory is that it's a highly mathematical theory, and the mathematics holds together in a very tight and consistent way. It contains in its basic structure both quantum mechanics and the theory of gravity. That's big news. — Leonard Susskind

As an adult I discovered that I was a pretty good autodidact, and can teach myself all kind of things. And developed a great interest in a number of different things from how to build a street hot rod from the ground up to quantum mechanics, and those two different kinds of mechanics, and it was really in the sciences, quantum mechanics, molecular biology, I would begin looking at these things looking for ideas, but in fact you don't read it for ideas you read it for curiosity and interest in the subject. — Dean Koontz

In the 'Many Worlds Interpretation of Quantum Mechanics,' the trajectory of your life is no longer just one straight path to an eventuality, but is instead one path of many, on an ever-branching tree of possibilities. — Kevin Michel

People are romantic idiots in the ideals of courtship. When a person says they have x, y, and z, their romantic counterpart takes x, y, and z as distinct points in a person's timeline-versus the imperceptibly messy distances in between (and the attributed entanglement). Thus resulting in happily never afters. — Solange Nicole

I find enough mystery in mathematics to satisfy my spiritual needs. I think, for example, that pi is mysterious enough (don't get me started!) without having to worry about God. Or if pi isn't enough, how about fractals? or quantum mechanics? — Tom Lehrer

Taking consciousness as a primitive rather than as an emergent property of the physical brain, Chalmers's search for a nonreductive ontology of consciousness led him to what he calls panprotopsychism. The proto reflects the possibility that the intrinsic properties of the basic entities of the physical world may be not quite mental, but that collectively they are able to constitute the mental (it is in this sense of proto that physics is "protochemical"). In this view, mind is much more fundamental to the universe than we ordinarily imagine. Panprotopsychism has the virtue of integrating mental events into the physical world. "We need psychophysical laws connecting physical processes to subjective experience," Chalmers says. "Certain aspects of quantum mechanics lend themselves very nicely to this. — Jeffrey M. Schwartz

Since the founding of quantum mechanics in the 1920s, theoretical physics had nurtured an extremely radical tradition. — David Gross

In 1965, physicist Richard Feynman opined, "I think I can safely say that nobody understands quantum mechanics," and the sentiment is equally applicable today. — Sean Carroll

It seems clear that the present quantum mechanics is not in its final form. Some further changes will be needed, just about as drastic as the changes made in passing from Bohr's orbit theory to quantum mechanics. Some day a new quantum mechanics, a relativistic one, will be discovered, in which we will not have these infinities occurring at all. It might very well be that the new quantum mechanics will have determinism in the way that Einstein wanted. — Paul Dirac

The current leading candidates for dark matter are particles predicted to exist from supersymmetric theories, extensions of current particle physics that include a new symmetry of Nature. The reader may recognize the "super" in supersymmetry from superstring theory, a candidate theory for unifying general relativity and quantum mechanics. As of the winter of 2014, no evidence for supersymmetry had been found, despite decades of intense search and the enthusiastic support of many physicists. At this point, it is unclear and somewhat doubtful that supersymmetry is realized in Nature. — Marcelo Gleiser

While many questions about quantum mechanics are still not fully resolved, there is no point in introducing needless mystification where in fact no problem exists. Yet a great deal of recent writing about quantum mechanics has done just that. — Murray Gell-Mann

In quantum mechanics there is A causing B. The equations do not stand outside that usual paradigm of physics. The real issue is that the kinds of things you predict in quantum mechanics are different from the kinds of things you predict using general relativity. Quantum mechanics, that big, new, spectacular remarkable idea is that you only predict probabilities, the likelihood of one outcome or another. That's the new idea. — Brian Greene

In other words, the idea is the there's a fourth level of parallel universes that's vastly larger than the three we've encountered so far, corresponding to different mathematical structures. The first three levels correspond to noncommunicating parallel universes within the same mathematical structure: Level I simply means distant regions from which light hasn't yet had time to reach us, Level II covers regions that are forever unreachable because of the cosmological inflation of intervening space, and Level III, Everett's "Many Worlds," involves noncommunicating parts of the Hilbert space of quantum mechanics. Whereas all the parallel universes at Levels I, II and III obey the same fundamental mathematical equations (describing quantum mechanics, inflation, etc.), Level IV parallel universes dance to the tunes of different equations, corresponding to different mathematical structures. Figure 12.2 illustrates this four-level multiverse hierarchy, one of the core ideas of this book. — Max Tegmark

Common sense has no place in Quantum Mechanics. — Michio Kaku

Quantum mechanics extends this relativity in a radical way: all variable aspects of an object exist only in relation to other objects. It is only in interactions that nature draws the world. — Carlo Rovelli

Despite the earnest belief of most of his fans, Einstein did not win his Nobel Prize for the theory of relativity, special or general. He won for explaining a strange effect in quantum mechanics, the photoelectric effect. His solution provided the first real evidence that quantum mechanics wasn't a crude stopgap for justifying anomalous experiments, but actually corresponds to reality. And the fact that Einstein came up with it is ironic for two reasons. One, as he got older and crustier, Einstein came to distrust quantum mechanics. Its statistical and deeply probabilistic nature sounded too much like gambling to him, and it prompted him to object that "God does not play dice with the universe." He was wrong, and it's too bad that most people have never heard the rejoinder by Niels Bohr: "Einstein! Stop telling God what to do. — Sam Kean

In particular, if consciousness is an ontological fundamental-that is, a primary element of reality-then it may have the power to achieve what is both the best-documented and at the same time the spookiest effect of the m ind on the material world: the ability of consciousness to transform the infinite possibilities for, say, the position of a subatomic particle as described by quantum mechanics into the single reality for that position as detected by an observer. If that sounds both mysterious and spooky, it is a spookiness that has been a part of science since almost the beginning of the twentieth century. It was physics that first felt the breath of this ghost, with the discoveries of quantum mechanics, and it is in the field of neuroscience and the problem of mind and matter that its ethereal presence is felt most markedly today. — Jeffrey M. Schwartz

When you ask what are electrons and protons I ought to answer that this question is not a profitable one to ask and does not really have a meaning. The important thing about electrons and protons is not what they are but how they behave, how they move. I can describe the situation by comparing it to the game of chess. In chess, we have various chessmen, kings, knights, pawns and so on. If you ask what chessman is, the answer would be that it is a piece of wood, or a piece of ivory, or perhaps just a sign written on paper, or anything whatever. It does not matter. Each chessman has a characteristic way of moving and this is all that matters about it. The whole game os chess follows from this way of moving the various chessmen. — Paul A.M. Dirac

Solipsism may be logically consistent with present Quantum Mechanics, Monism in the sense of Materialism is not. — Eugene Wigner

Any thoughtful physicist, he said, well schooled in quantum mechanics, would agree that all time exists simultaneously, which I subsequently learned was the case. In truth, Father said, as the first instant of the universe, all of time was present, all our yesterdays and today and all our tomorrows, everyone and everything that was and ever would be existed at that moment. — Dean Koontz

The more we delve into quantum mechanics the stranger the world becomes; appreciating this strangeness of the world, whilst still operating in that which you now consider reality, will be the foundation for shifting the current trajectory of your life from ordinary to extraordinary. It is the Tao of mixing this cosmic weirdness with the practical and physical, which will allow you to move, moment by moment, through parallel worlds to achieve your dreams. — Kevin Michel

Scientists, therefore, are responsible for their research, not only intellectually but also morally. This responsibility has become an important issue in many of today's sciences, but especially so in physics, in which the results of quantum mechanics and relativity theory have opened up two very different paths for physicists to pursue. They may lead us - to put it in extreme terms - to the Buddha or to the Bomb, and it is up to each of us to decide which path to take. — Fritjof Capra

The role of gender in society is the most complicated thing I've ever spent a lot of time learning about, and I've spent a lot of time learning about quantum mechanics. — Randall Munroe

In quantum mechanics no object has a definite position, except when colliding headlong with something else. — Carlo Rovelli

A popular feel for scientific endeavors should, if possible, be restored given the needs of the twenty-first century. This does not mean that every literature major should take a watered-down physics course or that a corporate lawyer should stay abreast of quantum mechanics. Rather, it means that an appreciation for the methods of science is a useful asset for a responsible citizenry. What science teaches us, very significantly, is the correlation between factual evidence and general theories, something well illustrated in Einstein's life. — Walter Isaacson

The basic idea is to shove all fundamental difficulties onto the neutron and to do quantum mechanics in the nucleus. — Werner Heisenberg

The theory of relativity and quantum mechanics argue that you can twist time and space, that something can appear out of nothing, and that a cat can be both alive and dead at the same time. This makes a mockery of our common sense, yet nobody seeks to protect innocent schoolchildren from these scandalous ideas. Why? The theory of relativity makes nobody angry, because it doesn't contradict any of our cherished beliefs. Most people don't care an iota whether space and time are absolute or relative. If you think it is possible to bend space and time, well, be my guest. Go ahead and bend them. What do I care? In contrast, Darwin has deprived us of our souls — Yuval Noah Harari

When the province of physical theory was extended to encompass microscopic phenomena through the creation of quantum mechanics, the concept of consciousness came to the fore again. It was not possible to formulate the laws of quantum mechanics in a fully consistent way without reference to the consciousness. — Eugene Wigner

Quantum mechanics says that it is completely correct to say that the universe's
evolution is determined not by how it started in the Big Bang, but by the final
state of the universe. Every stage of universal history, including every stage of logical and human history, is determined by the ultimate goal of the universe. And
if I am correct that the universal final state is indeed God, then every stage of universal
history, in particular every mutation that has ever occurred, or ever will occur
in any living being, is determined by the action of God. — Frank J. Tipler

Apparently, when people travel between dimensions, their physical forms are "no longer observable," which is a quantum mechanics thing, and explaining it involves this whole story about a cat that's in a box and is simultaneously alive and dead until you open the box, and it gets seriously complicated. Never ask a physicist about that cat. — Claudia Gray

The unsolved problems of the physical world now seem even more formidable than those solved in the twentieth century.

Though in application it works splendidly, we do not even understand the physical meaning of quantum mechanics, much less how it might be united with general relativity.

We don't know why the dimensionless constants (ratios of masses of elementary particles, ratios of strength of gravitational to electric forces, fine structure constant, etc.) have the values they do, unless we appeal to the implausible anthropic principle, which seems like a regression to Aristotelian teleology. — Gerald Holton

All of the patterns we've discussed of course exist in four dimensions rather than three, and the metaphors about braids, cables and trees, shouldn't be taken too literally. The key point is simply that you can be an unchanging pattern in spacetime-the specific details of this pattern are less important for the points we're making. This pattern is part of the mathematical structure that is our Universe, and the relations between different parts of the pattern are encoded in mathematical equations. As we saw in Chapter 8, Everett's quantum mechanics endows you with an even more interesting-but no less mathematical-structure, since a single you (the tree trunk) can split into many branches, each feeling that they're the one and only you
we'll return to this later. — Max Tegmark

Einstein comes along and says, space and time can warp and curve, that's what gravity is. Now string theory comes along and says, yes, gravity, quantum mechanics, electromagnetism - all together in one package, but only if the universe has more dimensions than the ones that we see. — Brian Greene

If the business of physics is ever finished, the world will be a much less interesting place in which to live . . . — John Gribbin

In relativity, movement is continuous, causally determinate and well defined, while in quantum mechanics it is discontinuous, not causally determinate and not well defined. — David Bohm

The universe, according to quantum mechanics, participates in a game of chance. — Brian Greene

Most 20th century academic physicists, and academia as a whole, simply did not want to touch the subject of consciousness. We have seen psychology grow up, and we've seen the development of neurophysiology and other much more sophisticated science, but only in the recent years have the tools of quantum mechanics been applied to anything representing human scale size. — Edgar Mitchell

If there is to be a resolution to the mystery of how mind relates to matter, it will emerge from explaining the data of the human brain in terms of these laws-laws capable of giving rise to a very different view of the causal efficacy of human consciousness. Quantum mechanics makes it feasible to describe a mind capable of exerting effects that neurons alone cannot. — Jeffrey M. Schwartz

A university student attending lectures on general relativity i the morning and others on quantum mechanics in the afternoon might be forgiven for thinking that his professors are fools, or have neglected to communicate with each other for at least a century. — Carlo Rovelli

Men wanted to be strong. One way to be strong was to be knowledgeable. In so many areas, it was not possible to be knowledgeable without getting a Ph.D. and doing a postdoc. Guns and hunting provided an out for men who wanted to be know-it-alls but who couldn't afford to spend the first three decades of their lives getting up to speed on quantum mechanics or oncology. — Neal Stephenson

Is the purpose of theoretical physics to be no more than a cataloging of all the things that can happen when particles interact with each other and separate? Or is it to be an understanding at a deeper level in which there are things that are not directly observable (as the underlying quantized fields are) but in terms of which we shall have a more fundamental understanding? — Julian Schwinger

All perception is the result of electrical impulses in the brain - the world of the individual is tantamount to a highly advanced computer running and analyzing programs in its working memory. — Kevin Michel

The belief in causality is metaphysical. It is nothing but a typical metaphysical hypostatization of a well-justified methodological rule- the scientist's decision never to abandon his search for laws. The metaphysical belief in causality seems thus more fertile in its various manifestations than any indeterminist physics metaphysics of the kind advocated by Heisenberg. Indeed, we can see that Heisenberg's comments have had a crippling effect on research. Connections which are not far to seek may easily be overlooked if its continually repeated that the search for any such connections is 'meaningless'. — Karl Popper

There is a widespread belief about quantum mechanics, as also about relativity, that it is something that one is entitled to ignore for most ordinary philosophical and scientific purposes, since it only seriously applies at the micro level of reality; where 'micro' means something far smaller than would show up in any conventional microscope. What sits on top of this micro level, so the assumption runs, is a sufficiently good approximation of the old classical Newtonian picture to justify our continuing, as philosophers, to think about the world in essentially classical terms. I believe this to be a fundamental mistake. What I shall be arguing...is that the world is quantum-mechanical through and through; and that the classical picture of reality is, even at the microscopic level, deeply inadequate. — Stephen T. DeBerry

The fine structure constant is undoubtedly the most fundamental pure (dimensionless) number in all of physics. It relates the basic constants of electromagnetism (the charge of the electron), relativity (the speed of light), and quantum mechanics (Planck's constant). — David J. Griffiths

I finished up my graduate degree in quantum mechanics, but underwent a bit of a personal crisis, recognizing that I didn't want to do that for the rest of my life. It was too abstract, too far removed from human concerns. — Francis Collins

In the world of the very small, where particle and wave aspects of reality are equally significant, things do not behave in any way that we can understand from our experience of the everyday world ... all pictures are false, and there is no physical analogy we can make to understand what goes on inside atoms. Atoms behave like atoms, nothing else. — John Gribbin

It has been said that the three great develpments in twentieth century science are relativity, quantum mechanics, and chaos. That strikes me the same as saying that the three great developments in twentith century engineering are the airplane, the computer, and the pop-top aluminum can. Chaos and fractals are not even twentieth century ideas: chaos was first observed by Poincare and fractals were familiar to Cantor a century ago, although neither man had the computer at his disposal to show the rest of the world the beauty he was seeing. — Robert L. Devaney

A. Douglas Stone, a physicist who has spent his life using quantum mechanics to explore striking new phenomena, has turned his considerable writing skills to thinking about Einstein and the quantum. What he finds and makes broadly understandable are the riches of Einstein's thinking not about relativity, not about his arguments with Bohr, but about Einstein's deep insights into the quantum world, insights that Stone shows speak to us now with all the vividness and depth they had a century ago. This is a fascinating book, lively, engaging, and strong in physical intuition. — Peter Galison

Wolfgang Pauli, in the months before Heisenberg's paper on matrix mechanics pointed the way to a new quantum theory, wrote to a friend, "At the moment physics is again terribly confused. In any case, it is too difficult for me, and I wish I had been a movie comedian or something of the sort and had never heard of physics." That testimony is particularly impressive if contrasted with Pauli's words less than five months later: "Heisenberg's type of mechanics has again given me hope and joy in life. To be sure it does not supply the solution to the riddle, but I believe it is again possible to march forward. — Wolfgang Pauli

One of the older professors in the department didn't find my talk very convincing and made sure that everyone in the room knew of his unhappiness. The next day he sent an e-mail around to the department faculty, which he was considerate enough to copy to me: Finally, the magnitude of the entropy of the universe as a function of time is a very interesting problem for cosmology, but to suggest that a law of physics depends on it is sheer nonsense. Carroll's statement that the second law owes its existence to cosmology is one of the dummest [sic] remarks I heard in any of our physics colloquia, apart from [redacted]'s earlier remarks about consciousness in quantum mechanics. I am astounded that physicists in the audience always listen politely to such nonsense. Afterwards, I had dinner with some graduate students who readily understood my objections, but Carroll remained adamant. I hope he reads this book. — Sean Carroll

Werner Heisenberg put it, "what we observe is not nature in itself, but nature exposed to our method of questioning." Heisenberg, a German physicist, made this observation regarding quantum mechanics, but it holds equally true for explorations of the animal — Frans De Waal

I find the idea quite intolerable that an electron exposed to radiation should choose of its own free will not only its moment to jump off but its direction. In that case I would rather be a cobbler, or even an employee in a gaming house, than a physicist. — Albert Einstein