Best 538 quotes in «physics quotes» category

The more important fundamental laws and facts of physical science have all been discovered, and these are now so firmly established that the possibility of their ever being supplanted in consequence of new discoveries is exceedingly remote. Nevertheless, it has been found that there are apparent exceptions to most of these laws, and this is particularly true when the observations are pushed to a limit, i.e., whenever the circumstances of experiment are such that extreme cases can be examined. Such examination almost surely leads, not to the overthrow of the law, but to the discovery of other facts and laws whose action produces the apparent exceptions. As instances of such discoveries, which are in most cases due to the increasing order of accuracy made possible by improvements in measuring instruments, may be mentioned: first, the departure of actual gases from the simple laws of the so-called perfect gas, one of the practical results being the liquefaction of air and all known gases; second, the discovery of the velocity of light by astronomical means, depending on the accuracy of telescopes and of astronomical clocks; third, the determination of distances of stars and the orbits of double stars, which depend on measurements of the order of accuracy of one-tenth of a second-an angle which may be represented as that which a pin's head subtends at a distance of a mile. But perhaps the most striking of such instances are the discovery of a new planet or observations of the small irregularities noticed by Leverrier in the motions of the planet Uranus, and the more recent brilliant discovery by Lord Rayleigh of a new element in the atmosphere through the minute but unexplained anomalies found in weighing a given volume of nitrogen. Many other instances might be cited, but these will suffice to justify the statement that 'our future discoveries must be looked for in the sixth place of decimals.

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.

The most fundamental laws of physics are not restrictions on the behaviour of matter. Rather, they are restrictions on the way physicists may describe that behaviour.

The myth of quantum consciousness sits well with many whose egos have made it impossible for them to accept the insignificant place science perceives for humanity, as modern instruments probe the farthest reaches of space and time. ... quantum consciousness has about as much substance as the aether from which it is composed. Early in this century, quantum mechanics and Einstein’s relativity destroyed the notion of a holistic universe that had seemed within the realm of possibility in the century just past. First, Einstein did away with the aether, shattering the doctrine that we all move about inside a universal, cosmic fluid whose excitations connect us simultaneously to one another and to the rest of the universe. Second, Einstein and other physicists proved that matter and light were composed of particles, wiping away the notion of universal continuity. Atomic theory and quantum mechanics demonstrated that everything, even space and time, exists in discrete bits – quanta. To turn this around and say that twentieth century physics initiated some new holistic view of the universe is a complete misrepresentation of what actually took place. ... The myth of quantum consciousness should take its place along with gods, unicorns, and dragons as yet another product of the fantasies of people unwilling to accept what science, reason, and their own eyes tell them about the world.

Then there are those who think their bodies don't exist. They live by mechanical time. They rise at seven o'clock in the morning. They eat their lunch at noon and their supper at six. They arrive at their appointments on time, precisely by the clock. They make love between eight and ten at night. They work forty hours a week, read the Sunday paper on Sunday, play chess on Tuesday nights. When their stomach growls, they look at their watch to see if it is time to eat. When they begin to lose themselves in a concert, they look at the clock above the stage to see when it will be time to go home. They know that the body is not a thing of wild magic, but a collection of chemicals, tissues, and nerve impulses. Thoughts are no more than electrical surges in the brain. Sexual arousal is no more than a flow of chemicals to certain nerve endings. Sadness no more than a bit of acid transfixed in the cerebellum. In short, the body is a machine, subject to the same laws of electricity and mechanics as an electron or clock. As such, the body must be addressed in the language of physics. And if the body speaks, it is the speaking only of so many levers and forces. The body is a thing to be ordered, not obeyed.

The opposite of a correct statement is an incorrect statement. The opposite of a profound truth is another profound truth (Niels Bohr)." By this, he means that we require a larger reading of the human past, of our relations with each other, the universe and God, a retelling of our older tales to encompass many truths and to let us grow with change.

Theoretical physics is the deepest and purest branch of science. It is the outpost of science closest to philosophy, and religion. Experimental scientists occupy themselves with observing and measuring the cosmos, finding out what stuff exists, no matter how strange that stuff may be. Theoretical physicists, on the other hand, are not satisfied with observing the universe. They want to know why .

The origin and the operation of the universe do not require any violations of the laws of physics.

The prime number 137 had continuously occupied Pauli's mind. It is an approximate value for a constant appearing in the fine structure theory of atomic spectra which in its theoretical expression ties together electromagnetism, relativity and quantum theory. Pauli saw the fine structure theory of spectra as a key in understanding the deepest contemporary problems of theoretical physics. For that reason the number 137 possessed a mysterious attraction for him.

The particles that are the very building blocks of all things, are in all possible locations until observation/measurement causes them to choose a specific position.

The philosophers make still another objection: "What you gain in rigour," they say, "you lose in objectivity. You can rise toward your logical ideal only by cutting the bonds which attach you to reality. Your science is infallible, but it can only remain so by imprisoning itself in an ivory tower and renouncing all relation with the external world. From this seclusion it must go out when it would attempt the slightest application.

The person who wishes to attain human perfection should study logic first, next mathematics, then physics, and, lastly, metaphysics.

The power and beauty of physical laws is that they apply everywhere, whether or not you choose to believe in them. In other words, after the laws of physics, everything else is opinion.

The power of the deductive network produced in physics has been illustrated in a delightful article by Victor F. Weisskopf. He begins by taking the magnitudes of six physical constants known by measurement: the mass of the proton, the mass and electric charge of the electron, the light velocity, Newton's gravitational constant, and the quantum of action of Planck. He adds three of four fundamental laws (e.g., de Broglie's relations connecting particle momentum and particle energy with the wavelength and frequency, and the Pauli exclusion principle), and shows that one can then derive a host of different, apparently quite unconnected, facts that happen to be known to us by observation separately ....

The ray of light has to know where it will ultimately end up before it can choose the direction to begin moving in" "Fermat's principle sounds weird because it describes light's behavior in goal-oriented terms. It sounds like a commandment to a light beam: "Thou shalt minimize or maximize the time taken to reach thy destination.

The realization that time can behave like another direction of space means one can get rid of the problem of time having a beginning, in a similar way in which we got rid of the edge of the world. Suppose the beginning of the universe was like the South Pole of the earth, with degrees of latitude playing the role of time. As one moves north, the circles of constant latitude, representing the size of the universe, would expand. The universe would start as a point at the South Pole, but the South Pole is much like any other point. To ask what happened before the beginning of the universe would become a meaningless question, because there is nothing south of the South Pole.

… there are no arbitrary constants ... nature is so constituted that it is possible logically to lay down such strongly determined laws that within these laws only rationally determined constants occur (not constants, therefore, whose numerical value could be changed without destroying the theory).

There are only two types of waves that can travel across the universe bringing us information about things far away: electromagnetic waves (which include light, X-rays, gamma rays, microwaves, radio waves…); and gravitational waves. Electromagnetic waves consist of oscillating electric and magnetic forces that travel at light speed. When they impinge on charged particles, such as the electrons in a radio or TV antenna, they shake the particles back and forth, depositing in the particles the information the waves carry. That information can then be amplified and fed into a loudspeaker or on to a TV screen for humans to comprehend. Gravitational waves, according to Einstein, consist of an oscillatory space warp: an oscillating stretch and squeeze of space. In 1972 Rainer (Rai) Weiss at the Massachusetts Institute of Technology had invented a gravitational-wave detector, in which mirrors hanging inside the corner and ends of an L-shaped vacuum pipe are pushed apart along one leg of the L by the stretch of space, and pushed together along the other leg by the squeeze of space. Rai proposed using laser beams to measure the oscillating pattern of this stretch and squeeze. The laser light could extract a gravitational wave’s information, and the signal could then be amplified and fed into a computer for human comprehension. The study of the universe with electromagnetic telescopes (electromagnetic astronomy) was initiated by Galileo, when he built a small optical telescope, pointed it at Jupiter and discovered Jupiter’s four largest moons. During the 400 years since then, electromagnetic astronomy has completely revolutionised our understanding of the universe.

There are over a million types of fish in the sea as there are flowers in all of the world's gardens. There are at least a million different types of minerals as there are species of birds or monkeys. The possible configurations of lifeforms that could be created from a single atom are infinite. There are at least a billion people on this earth, and no two faces look the same. It is very arrogant to assume that we have seen all of God's miracles.

There are reasons to doubt that what we call the laws of physics necessarily apply everywhere in the universe—or that they were applicable to every time in its history.

There are other reasons we use math in physics. Besides keeping us honest, math is also the most economical and unambiguous terminology that we know of. Language is malleable; it depends on context and interpretation. But math doesn’t care about culture or history. If a thousand people read a book, they read a thousand different books. But if a thousand people read an equation, they read the same equation.

There was a young lady named Bright, Whose speed was far faster than light; She started one day In a relative way, And returned on the previous night.

There is a strange ring of feeling and emotion in these reactions [of scientists to evidence that the universe had a sudden beginning]. They come from the heart whereas you would expect the judgments to come from the brain. Why? I think part of the answer is that scientists cannot bear the thought of a natural phenomenon which cannot be explained, even with unlimited time and money. There is a kind of religion in science; it is the religion of a person who believes there is order and harmony in the Universe. Every event can be explained in a rational way as the product of some previous event; every effect must have its cause, there is no First Cause. … This religious faith of the scientist is violated by the discovery that the world had a beginning under conditions in which the known laws of physics are not valid, and as a product of forces or circumstances we cannot discover. When that happens, the scientist has lost control. If he really examined the implications, he would be traumatized.

There is only one universal language, which is the language of numbers and proportions that are so striking and stunningly built into the Great Pyramid and to which our current science has no appropriate response. We can no longer ignore that this ancient civilization was aware of our units used in modern mathematics and physics and were even aware of our metric system. Our metric system originating in the eighteenth century, designed and implemented by a committee of mathematicians and physicists commissioned by the French revolutionary government.

There's a variation of the ever popular multiverse idea in which the multiple universes that comprise it are not separate universes entirely, but isolated, non-interacting pockets of space within one continuous fabric of space time - like multiple ships at sea, far enough away from one another so that their circular horizons do not intersect. As far as any one ship is concerned (without further data), it's the only ship on the ocean, yet they all share the same body of water.

There was no room for dust devils in the laws of physics, as least in the rigid form in which they were usually taught. There is a kind of unspoken collusion going on in mainstream science education: you get your competent but bored, insecure and hence stodgy teacher talking to an audience divided between engineering students, who are going to be responsible for making bridges that won’t fall down or airplanes that won’t suddenly plunge vertically into the ground at six hundred miles an hour, and who by definition get sweaty palms and vindictive attitudes when their teacher suddenly veers off track and begins raving about wild and completely nonintuitive phenomena; and physics students, who derive much of their self-esteem from knowing that they are smarter and morally purer than the engineering students, and who by definition don’t want to hear about anything that makes no fucking sense. This collusion results in the professor saying: (something along the lines of) dust is heavier than air, therefore it falls until it hits the ground. That’s all there is to know about dust. The engineers love it because they like their issues dead and crucified like butterflies under glass. The physicists love it because they want to think they understand everything. No one asks difficult questions. And outside the windows, the dust devils continue to gambol across the campus.

The rules of physics are, in some cases, suspiciously anthropic.

The reason Dick's physics was so hard for ordinary people to grasp was that he did not use equations. The usual theoretical physics was done since the time of Newton was to begin by writing down some equations and then to work hard calculating solutions of the equations. This was the way Hans and Oppy and Julian Schwinger did physics. Dick just wrote down the solutions out of his head without ever writing down the equations. He had a physical picture of the way things happen, and the picture gave him the solutions directly with a minimum of calculation. It was no wonder that people who had spent their lives solving equations were baffled by him. Their minds were analytical; his was pictorial.

There can never be a clock at the center of the Universe to which everyone can set their watches. Your entire life can be the blink of an eye to an alien who leaves Earth traveling close to the speed of light, then returns an hour later to find that you have been dead for centuries.

There is a voice that doesn't use words. LISTEN. Listen to silence, it has so much to say. Let silence take you to the core of life.

[There is] no direct relationship between IQ and economic opportunity. In the supposed interests of fairness and “social justice”, the natural relationship has been all but obliterated. Consider the first necessity of employment, filling out a job application. A generic job application does not ask for information on IQ. If such information is volunteered, this is likely to be interpreted as boastful exaggeration, narcissism, excessive entitlement, exceptionalism [...] and/or a lack of team spirit. None of these interpretations is likely to get you hired. Instead, the application contains questions about job experience and educational background, neither of which necessarily has anything to do with IQ. Universities are in business for profit; they are run like companies, seek as many paying clients as they can get, and therefore routinely accept people with lukewarm IQ’s, especially if they fill a slot in some quota system (in which case they will often be allowed to stay despite substandard performance). Regarding the quotas themselves, these may in fact turn the tables, advantaging members of groups with lower mean IQ’s than other groups [...] sometimes, people with lower IQ’s are expressly advantaged in more ways than one. These days, most decent jobs require a college education. Academia has worked relentlessly to bring this about, as it gains money and power by monopolizing the employment market across the spectrum. Because there is a glut of college-educated applicants for high-paying jobs, there is usually no need for an employer to deviate from general policy and hire an applicant with no degree. What about the civil service? While the civil service was once mostly open to people without college educations, this is no longer the case, and quotas make a very big difference in who gets hired. Back when I was in the New York job market, “minorities” (actually, worldwide majorities) were being spotted 30 (thirty) points on the civil service exam; for example, a Black person with a score as low as 70 was hired ahead of a White person with a score of 100. Obviously, any prior positive correlation between IQ and civil service employment has been reversed. Add to this the fact that many people, including employers, resent or feel threatened by intelligent people [...] and the IQ-parameterized employment function is no longer what it was once cracked up to be. If you doubt it, just look at the people running things these days. They may run a little above average, but you’d better not be expecting to find any Aristotles or Newtons among them. Intelligence has been replaced in the job market with an increasingly poor substitute, possession of a college degree, and given that education has steadily given way to indoctrination and socialization as academic priorities, it would be naive to suppose that this is not dragging down the overall efficiency of society. In short, there are presently many highly intelligent people working very “dumb” jobs, and conversely, many less intelligent people working jobs that would once have been filled by their intellectual superiors. Those sad stories about physics PhD’s flipping burgers at McDonald's are no longer so exceptional. Sorry, folks, but this is not your grandfather’s meritocracy any more.

There is no logical necessity for the existence of a unique direction of total time; whether there is only one time direction, or whether time directions alternate, depends on the shape of the entropy curve plotted by the universe.

There is something lamentable, degrading, and almost insane in pursuing the visionary schemes of past ages with dogged determination, in paths of learning which have been investigated by superior minds, and with which such adventurous persons are totally unacquainted. The history of Perpetual Motion is a history of the fool-hardiness of either half-learned, or totally ignorant persons.

There is something stunningly narrow about how the Anthropic Principle is phrased. Yes, only certain laws and constants of nature are consistent with our kind of life. But essentially the same laws and constants are required to make a rock. So why not talk about a Universe designed so rocks could one day come to be, and strong and weak Lithic Principles? If stones could philosophize, I imagine Lithic Principles would be at the intellectual frontiers.

There was a graduate student in my cohort, this guy I dated, who told me he came to realize that doing physics is like this: there's a concrete wall twenty feet thick, and you're on one side, and on the other side is everything worth knowing. And all you have is a spoon. So you just have to take a spoon and start scraping at the wall: no other way. He works in a bookstore now. But I think of it this way. There is a jigsaw puzzle. It's infinitely large, with no edges or corners to help you out. We have to put it together: it's our duty. We will never finish, but we have to find our satisfactions where we can: when we place two pieces together that suggest we may have found the place where the sky touches the sea, or when we discover a piece that is beautiful in and of itself, that has an unusual color or a glimpse of an unexpected pattern. And the pieces that do not join together also tell you something. If there are very few eureka moments, then at least there are a thousand little failures, that point the way toward a hundred little joys.

There was a sense that the one true theory had been discovered. Nothing else was important or worth thinking about. Seminars devoted to string theory sprang up at many of the major universities and research institutes. At Harvard, the string theory seminar was called the Postmodern Physics seminar. This appellation was not meant ironically.

There was yet another disadvantage attaching to the whole of Newton’s physical inquiries, ... the want of an appropriate notation for expressing the conditions of a dynamical problem, and the general principles by which its solution must be obtained. By the labours of LaGrange, the motions of a disturbed planet are reduced with all their complication and variety to a purely mathematical question. It then ceases to be a physical problem; the disturbed and disturbing planet are alike vanished: the ideas of time and force are at an end; the very elements of the orbit have disappeared, or only exist as arbitrary characters in a mathematical formula.

The significance of [the fine-structure constant] goes far beyond atomic physics, however. It is the smallness of 1/137 compared to unity that enables us to treat the coupling between the electromagnetic field and a charged particle such as an electron as a small perturbation, a fact of great computational importance. [Forces of Nature]

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?

The theoretical determination of the fine structure constant is certainly the most important of the unsolved problems of modern physics. We believe that any regression to the ideas of classical physics (as, for instance, to the use of the classical field concept)cannot bring us nearer to this goal. To reach it, we shall, presumably, have to pay with further revolutionary changes of the fundamental concepts of physics with a still farther digression from the concepts of the classical theories.

The standard cosmological theory--an expanding universe--does not really solve the problem of God. It simply makes it more problematical. Once the creator-creation model is discarded as primitive mythology, we still have not touched the ancient conundrum, ex nihilo nihil fit: nothing comes from nothing, and the "axiom" that "Nothing is unstable' rivals in scholastic absurdity anything Aquinas may have said eight hundred years ago and can only be postulated given the reality of something, whereby it becomes a self-evident and unarguable tautology.

The time is my vehicle & the light is my fuel.

The transition of nothing-to-something is a natural one, not requiring any agent.

The universe, the whole mass of things that are, is corporeal, that is to say, body, and hath the dimensions of magnitude, length, breadth and depth. Every part of the universe is ‘body’ and that which is not ‘body’ is no part of the universe, and because the universe is all, that which is no part of it is nothing, and consequently nowhere.

The universe as a giant harpstring, oscillating in and out of existence! What note does it play, by the way? Passages from the Numerical Harmonies, I supposed?

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.

The world offers many possibilities for different sensory universes, which support very different interpretations of the world's significance. In this way our so-called Universe is already very much a multiverse.

The whole point of physics is to use maths to describe the universe.

.... the world is made entirely from quantum fields. These fields do not live *in* spacetime; they live, so to speak, one on top of the other: fields on fields. The space and time that we perceiv in large scale are our blurred and approximage image of one of these quantum fields: the gravitational field (193).

This change in the conception of reality is the most profound and the most fruitful that physics has experienced since the time of Newton. {Referring to James Clerk Maxwell's contributions to physics}