Best 538 quotes in «physics quotes» category

He (Comings) has in the past performed successful energy-converting experiments, creating a ringing resonance by injecting certain frequencies into piezo-electric crystals. When the crystal was in resonance with the plenum of space, the power output rose significantly higher than the input. He concluded that, if allowed politically, such discoveries could guide humankind in building a completely clean energy infrastructure -- resonant technologies that allow us to live in harmony with the universal energy field and the Earth.

Heisenberg's uncertainty relation measures the amount by which the complementary descriptions of the electron, or other fundamental entities, overlap. Position is very much a particle property - particles can be located precisely. Waves, on the other hand, have no precise location, but they do have momentum. The more you know about the wave aspect of reality, the less you know about the particle, and vice versa. Experiments designed to detect particles always detect particles; experiments designed to detect waves always detect waves. No experiment shows the electron behaving like a wave and a particle at the same time.

He needs "space" and "time," as if this were physics and not a human relationship.

Here the attention of the research workers is primarily directed to the problem of reconciling the claims of the special relativity theory with those of the quantum theory. The extraordinary advances made in this field by Dirac ... leave open the question whether it will be possible to satisfy the claims of the two theories without at the same time determining the Sommerfeld fine-structure constant.

Highly complex numbers like the Comma of Pythagoras, Pi and Phi (sometimes called the Golden Proportion), are known as irrational numbers. They lie deep in the structure of the physical universe, and were seen by the Egyptians as the principles controlling creation, the principles by which matter is precipitated from the cosmic mind. Today scientists recognize the Comma of Pythagoras, Pi and the Golden Proportion as well as the closely related Fibonacci sequence are universal constants that describe complex patterns in astronomy, music and physics. ... To the Egyptians these numbers were also the secret harmonies of the cosmos and they incorporated them as rhythms and proportions in the construction of their pyramids and temples.

His laws changed all of physics and astronomy. His laws made it possible to calculate the mass of the sun and planets. The way it's done is immensely beautiful. If you know the orbital period of any planet, say, Jupiter or the Earth and you know its distance to the Sun; you can calculate the mass of the Sun. Doesn't this sound like magic? We can carry this one step further - if you know the orbital period of one of Jupiter's bright moons, discovered by Galileo in 1609, and you know the distance between Jupiter and that moon, you can calculate the mass of Jupiter. Therefore, if you know the orbital period of the moon around the Earth (it's 27.32 days), and you know the mean distance between the Earth and the moon (it's about 200,039 miles), then you can calculate to a high degree of accuracy the mass of the Earth. … But Newton's laws reach far beyond our solar system. They dictate and explain the motion of stars, binary stars, star clusters, galaxies and even clusters of galaxies. And Newton's laws deserve credit for the 20th century discovery of what we call dark matter. His laws are beautiful. Breathtakingly simple and incredibly powerful at the same time. They explain so much and the range of phenomena they clarify is mind boggling. By bringing together the physics of motion, of interaction between objects and of planetary movements, Newton brought a new kind of order to astronomical measurements, showing how, what had been a jumble of confused observations made through the centuries were all interconnected.

I am an atheist.

...I am not, however, militant in my atheism. The great English theoretical physicist Paul Dirac is a militant atheist. I suppose he is interested in arguing about the existence of God. I am not. It was once quipped that there is no God and Dirac is his prophet.

I am more often wrong than right.

I believe that this Nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to earth.

I am not religious in any sense; in fact, I consider myself an atheist.

I am supposed to be helping her prepare for the GRE. Instead, we spend most of the time talking about color. The color of my clothes and shoes. The color of other people's clothes and shoes. The color of the sky when the sun has dipped just low enough to cause red light to bend the most and then, voilà, a sunset.

Ich selbst spiele nie Billard, [...],aber ich weiß, dass man den Ball hoch oder tief, rechts oder links nehmen kann; man kann den zweiten Ball voll treffen oder streifen; man kann stark oder schwach stoßen; die Fälsche stärker oder schwächer wählen; und sicher gibt es noch viele solcher Möglichkeiten. Ich kann mir nun jedes dieser Elemente beliebig abgestuft denken, so gibt es also nahezu unendlich viele Kombinationsmöglichkeiten. Wollte ich sie theoretisch ermitteln, so müßte ich außer den Gesetzen der Mathematik und der Mechanik starrer Körper auch die der Elastizitätslehre berücksichtigen; ich müßte die Koeffizienten des Materials kennen; den Temperatureinfluß; ich müßte die feinsten Maßmethoden für die Koordination und Abstufung meiner motorischen Impulse besitzen; meine Distanzschätzung müßte genau wie ein Nonius sein; mein kombinatorisches Vermögen schneller und sicherer als ein Rechenschieber; zu schweigen von der Fehlerrechnung, die Streungsbreite und dem Umstand, daß das zu erreichende Ziel der richtigen Koinzidenz der beiden Bälle selbst kein eindeutiges ist, sondern eine um einen Mittelwert gelagerte Gruppe von eben noch genügenden Tatbeständen darstellt.

If all astronomical processes cease, how will the passage of time manifest itself? It is doubtful if vacuum fluctuations can provide a clock for the recording of time. Will time itself come to a stop? Is this a meaningful question? Such questions are difficult to answer.

I don't believe any scientific field to be superior to another.

If and when all the laws governing physical phenomena are finally discovered, and all the empirical constants occurring in these laws are finally expressed through the four independent basic constants, we will be able to say that physical science has reached its end, that no excitement is left in further explorations, and that all that remains to a physicist is either tedious work on minor details or the self-educational study and adoration of the magnificence of the completed system. At that stage physical science will enter from the epoch of Columbus and Magellan into the epoch of the National Geographic Magazine!

If antimatter and matter make contact, both are destroyed instantly. Physicists call the process ‘annihilation.

I forget if it was the Mathematician of Alexandria who said that geometry is beauty laid bare or the Father of Relativity who made the claim for physics,” Darger said. “She is, in either case, ravishing.

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.

If magic violates the fundamental laws of nature, they clearly weren't all that fundamental.

If the deep logic of what determines the value of the fine-structure constant also played a significant role in our understanding of all the physical processes in which the fine-structure constant enters, then we would be stymied. Fortunately, we do not need to know everything before we can know something.

If someone tells you that something is impossible and you believe them, you should probably not be a researcher.

If the universe is movement, it will not be in one direction only. We think of our lives as linear but it is the spin of the earth that allows us to observe time. Walk with me.

If these d'Herelle bodies were really genes, fundamentally like our chromosome genes, they would give us an utterly new angle from which to attack the gene problem. They are filterable, to some extent isolable, can be handled in test-tubes, and their properties, as shown by their effects on the bacteria, can then be studied after treatment. It would be very rash to call these bodies genes, and yet at present we must confess that there is no distinction known between the genes and them. Hence we can not categorically deny that perhaps we may be able to grind genes in a mortar and cook them in a beaker after all. Must we geneticists become bacteriologists, physiological chemists and physicists, simultaneously with being zoologists and botanists? Let us hope so.

If we ascribe the ejection of the proton to a Compton recoil from a quantum of 52 x 106 electron volts, then the nitrogen recoil atom arising by a similar process should have an energy not greater than about 400,000 volts, should produce not more than about 10,000 ions, and have a range in the air at N.T.P. of about 1-3mm. Actually, some of the recoil atoms in nitrogen produce at least 30,000 ions. In collaboration with Dr. Feather, I have observed the recoil atoms in an expansion chamber, and their range, estimated visually, was sometimes as much as 3mm. at N.T.P. These results, and others I have obtained in the course of the work, are very difficult to explain on the assumption that the radiation from beryllium is a quantum radiation, if energy and momentum are to be conserved in the collisions. The difficulties disappear, however, if it be assumed that the radiation consists of particles of mass 1 and charge 0, or neutrons. The capture of the a-particle by the Be9 nucleus may be supposed to result in the formation of a C12 nucleus and the emission of the neutron. From the energy relations of this process the velocity of the neutron emitted in the forward direction may well be about 3 x 109 cm. per sec. The collisions of this neutron with the atoms through which it passes give rise to the recoil atoms, and the observed energies of the recoil atoms are in fair agreement with this view. Moreover, I have observed that the protons ejected from hydrogen by the radiation emitted in the opposite direction to that of the exciting a-particle appear to have a much smaller range than those ejected by the forward radiation. This again receives a simple explanation on the neutron hypothesis.

If you can fathom quantum mechanics without getting dizzy, you don't get it Et kvantebitte spring nærmere supercomputeren

If you see an antimatter version of yourself running towards you, think twice before embracing.

I have led an extraordinary life on this planet, while at the same time travelling across the universe by using my mind and the laws of physics. I have been to the furthest reaches of our galaxy, travelled into a black hole and gone back to the beginning of time. On Earth, I have experienced highs and lows, turbulence and peace, success and suffering. I have been rich and poor, I have been able-bodied and disabled. I have been praised and criticised, but never ignored. I have been enormously privileged, through my work, in being able to contribute to our understanding of the universe. But it would be an empty universe indeed if it were not for the people I love, and who love me. Without them, the wonder of it all would be lost on me. And at the end of all this, the fact that we humans, who are ourselves mere collections of fundamental particles of nature, have been able to come to an understanding of the laws governing us, and our universe, is a great triumph. I want to share my excitement about these big questions and my enthusiasm about this quest.

If you want to win this argument with Dad, look in chapter two of the first book of the Feynman Lectures on Physics. There's a quote there about how philosophers say a great deal about what science absolutely requires, and it is all wrong, because the only rule in science is that the final arbiter is observation - that you just have to look at the world and report what you see. Um... off the top of my head I can't think of where to find something about how it's an ideal of science to settle things by experiment instead of arguments -

If you were standing in the path of the beam, you would obviously die pretty quickly. You wouldn't really die of anything, in the traditional sense. You would just stop being biology and start being physics.

I have been able to solve a few problems of mathematical physics on which the greatest mathematicians since Euler have struggled in vain ... But the pride I might have held in my conclusions was perceptibly lessened by the fact that I knew that the solution of these problems had almost always come to me as the gradual generalization of favorable examples, by a series of fortunate conjectures, after many errors. I am fain to compare myself with a wanderer on the mountains who, not knowing the path, climbs slowly and painfully upwards and often has to retrace his steps because he can go no further—then, whether by taking thought or from luck, discovers a new track that leads him on a little till at length when he reaches the summit he finds to his shame that there is a royal road by which he might have ascended, had he only the wits to find the right approach to it. In my works, I naturally said nothing about my mistake to the reader, but only described the made track by which he may now reach the same heights without difficulty.

I could use the fresh air. I think that put my brain to sleep.” She pointed at the text as if it was a piece of rotten meat. “Physics?” I said. “You must need a more advanced text.” “No, it’s just boring.” I picked the book up and double checked the title, to make sure I hadn’t misidentified the subject. “Boring?” I said. “How can physics be …?” I looked up to see she’d already left the room. Simon pointed at the text, grinned and faked a yawn. “Hold on,” I said, striding after her. “Physics is not boring. Maybe you just need me to explain it better. Chloe? Chloe!

I'll never understand. Advanced physics is about describing things you can't know intuitively, so you describe it in numbers, but I've got it in front of me." He was looking around the room rather than at her. He seemed to like it, and since coming in, had eased closer to the burners. "It's like listening to blind people with no sense of touch prove atom by atom the existence and possible features of an elephant when I'm not even very interested in elephants.

In conclusion, I return to Einstein. If we find a planet in the Alpha Centauri system, its image, captured by a camera travelling at a fifth of light speed, will be slightly distorted due to the effects of special relativity. It would be the first time a spacecraft has flown fast enough to see such effects. In fact, Einstein’s theory is central to the whole mission. Without it we would have neither lasers nor the ability to perform the calculations necessary for guidance, imaging and data transmission over twenty-five trillion miles at a fifth of light speed. We can see a pathway between that sixteen-year-old boy dreaming of riding on a light beam and our own dream, which we are planning to turn into a reality, of riding our own light beam to the stars. We are standing at the threshold of a new era. Human colonisation on other planets is no longer science fiction. It can be science fact. The human race has existed as a separate species for about two million years. Civilisation began about 10,000 years ago, and the rate of development has been steadily increasing. If humanity is to continue for another million years, our future lies in boldly going where no one else has gone before. I hope for the best. I have to. We have no other option.

In fact, meta- and particle physicists have more in common than one might suppose: both tug, if in slightly different directions, at the knots which hold the cosmos together, both look beyond the immediate world of sense perception into one where cause can only be deduced from effect - a quark is as invisible as an angel; both are confronted by Manichaean polarities - miracles and black magic, cheap energy versus total destruction.

[In high school] my interests outside my academic work were debating, tennis, and to a lesser extent, acting. I became intensely interested in astronomy and devoured the popular works of astronomers such as Sir Arthur Eddington and Sir James Jeans, from which I learnt that a knowledge of mathematics and physics was essential to the pursuit of astronomy. This increased my fondness for those subjects.

In modern society, it is not enough to be an engineer, a doctor, a chemist, a biologist, or a physicist, you must be all of them to understand why human health is failing on such a massive scale.

‎In modern physics, there is no such thing as "nothing." Even in a perfect vacuum, pairs of virtual particles are constantly being created and destroyed. The existence of these particles is no mathematical fiction. Though they cannot be directly observed, the effects they create are quite real. The assumption that they exist leads to predictions that have been confirmed by experiment to a high degree of accuracy.

In mathematics, in physics, people are concerned with what you say, not with your certification. But in order to speak about social reality, you must have the proper credentials, particularly if you depart from the accepted framework of thinking. Generally speaking, it seems fair to say that the richer the intellectual substance of a field, the less there is a concern for credentials, and the greater is concern for content.

...in microphysics the observer interferes with the experiment in a way that can't be measured and that therefore can't be eliminated. No natural laws can be formulated, saying "such-and-such will happen in every case." All the microphysicist can say is "such-and-such is, according to statistical probability, likely to happen." This naturally represents a tremendous problem for our classical physical thinking. It requires a consideration, in a scientific experiment, of the mental outlook of the participant-observer: It could this be said that scientists can no longer hope to describe any aspects or qualities of outer objects in a completely independent, "objective" manner.

I noticed that the [drawing] teacher didn't tell people much... Instead, he tried to inspire us to experiment with new approaches. I thought of how we teach physics: We have so many techniques - so many mathematical methods - that we never stop telling the students how to do things. On the other hand, the drawing teacher is afraid to tell you anything. If your lines are very heavy, the teacher can't say, "Your lines are too heavy." because *some* artist has figured out a way of making great pictures using heavy lines. The teacher doesn't want to push you in some particular direction. So the drawing teacher has this problem of communicating how to draw by osmosis and not by instruction, while the physics teacher has the problem of always teaching techniques, rather than the spirit, of how to go about solving physical problems.

In short, the idea dawns that the one universal principle which possibly ... between force and structure, the embodiment of the Principle of Least Action and the (unknown) force, which in mathematics is known as the attractor which pulls ... in the direction of the most optimal and relatively stable self-organized criticality, could very well be the Golden Ratio dynamic. the universal principle which as the balance between finiteness and infinity, stability and flexibility underlies self-similar fractal forms emerging at the 'edge of chaos' indeed seems to be the Golden Ratio Spiral.

Instead, I opened my eyes to find the thing in front of my face, wafting dead horse breath across my chin and up my nose, its mouth like a gaping maw; its eyes, two giant wormholes, twisting and bending with some apparitional substance that could have been space and time if I’d known anything about physics.

Interestingly enough, whenever I cite examples from superhero comic books in a lecture, my students never wonder when they will use this information in their "real life". Apparently they all have plans, post-graduation, that involve protecting the City from all threat while wearing spandex. As a law-abiding citizen, this notion fills me with a great sense of security, knowing as I do how many of my scientist colleagues could charitably be termed "mad".

In the 1920s, there was a dinner at which the physicist Robert W. Wood was asked to respond to a toast ... 'To physics and metaphysics.' Now by metaphysics was meant something like philosophy—truths that you could get to just by thinking about them. Wood took a second, glanced about him, and answered along these lines: The physicist has an idea, he said. The more he thinks it through, the more sense it makes to him. He goes to the scientific literature, and the more he reads, the more promising the idea seems. Thus prepared, he devises an experiment to test the idea. The experiment is painstaking. Many possibilities are eliminated or taken into account; the accuracy of the measurement is refined. At the end of all this work, the experiment is completed and ... the idea is shown to be worthless. The physicist then discards the idea, frees his mind (as I was saying a moment ago) from the clutter of error, and moves on to something else. The difference between physics and metaphysics, Wood concluded, is that the metaphysicist has no laboratory.

In the beginning, there was physics. "Physics" describes how matter, energy, space, and time behave and interact with one another. The interplay of these characters in our cosmic drama underlies all biological and chemical phenomena. Hence everything fundamental and familiar to us earthlings begins with, and rests upon, the laws of physics. When we apply these laws to astronomical settings, we deal with physics writ large, which we call astrophysics.

In the context of physics, 137 is equal to the integer part of the inverse of the fine structure constant ... The fine structure constant α is the key to the physicist’s quest for a Grand Unified Theory ... The number 137 has intrigued numerous prominent theoretical physicists ... All told, we believe that it is much easier, and more motivating, to remember a number that has deep significance in numerous disciplines, ... with the following terse ode to 137: Bethe was mischievous with 137 Bohr was intrigued by 137 Born was mystified by 137 Fermi was frisky with 137 Feynman was mesmerized by 137 Heisenberg was fascinated by 137 Lederman was enchanted by 137 Pauli was consumed by 137 Turing was matched by 137

In the book of Job, the Lord demands, “Where wast thou when I laid the foundations of the earth?” “I was there!”-surely that is the answer to God’s question. For no matter how the universe came into being, most of the atoms in these fleeting assemblies that we think of as our bodies have been in existence since the beginning. Each breath we take contains hundreds of thousands of the inert, pervasive argon atoms that were actually breathed in his lifetime by the Buddha, and indeed contain parts of all the ‘snorts, sighs, bellows, shrieks” of all creatures that ever existed or will exist. These atoms flow backward and forward in such useful but artificial constructs as time and space, in the same universal rhythms, universal breath as the tides and stars, joining both the living and the dead in that energy which animates the universe.

In the far future, which promises to be vastly longer than our past (like a googolplex of years to our future versus 13.8 billion years to our past), all of the stars in the universe will have run out of fuel. Those that can will collapse to black holes; eventually everything will fall into stellar-mass black holes, and those black holes will fall into supermassive black holes, and then all of the black holes in the universe will eventually vaporize into Hawking radiation. This will take a very long time. ("Eternity is a very long time, especially towards the end.") All of the Hawking radiation will dissipate in an ever-expanding cosmos, unable to fill the swelling void, and the light in the universe will go out. Eventually, ever particle will find itself alone, no bright sky above, no luminous solar systems below. For now, we're here and the skies are bright, if somewhat quite. The gamble is that the skies aren't silent.

In the history of philosophy, the term “rationalism” has two distinct meanings. In one sense, it signifies an unbreached commitment to reasoned thought in contrast to any irrationalist rejection of the mind. In this sense, Aristotle and Ayn Rand are preeminent rationalists, opposed to any form of unreason, including faith. In a narrower sense, however, rationalism contrasts with empiricism as regards the false dichotomy between commitment to so-called “pure” reason (i.e., reason detached from perceptual reality) and an exclusive reliance on sense experience (i.e., observation without inference therefrom). Rationalism, in this sense, is a commitment to reason construed as logical deduction from non-observational starting points, and a distrust of sense experience (e.g., the method of Descartes). Empiricism, according to this mistaken dichotomy, is a belief that sense experience provides factual knowledge, but any inference beyond observation is a mere manipulation of words or verbal symbols (e.g., the approach of Hume). Both Aristotle and Ayn Rand reject such a false dichotomy between reason and sense experience; neither are rationalists in this narrow sense. Theology is the purest expression of rationalism in the sense of proceeding by logical deduction from premises ungrounded in observable fact—deduction without reference to reality. The so-called “thinking” involved here is purely formal, observationally baseless, devoid of facts, cut off from reality. Thomas Aquinas, for example, was history’s foremost expert regarding the field of “angelology.” No one could match his “knowledge” of angels, and he devoted far more of his massive Summa Theologica to them than to physics.