Best 538 quotes in «physics quotes» category

It has today occurred to me that an amplifier using semiconductors rather than vacuum is in principle possible. [Laboratory notebook, 29 Dec 1939.]

I think nature's imagination Is so much greater than man's, she's never going to let us relax

It is hardly surprising that there are more things in heaven and earth, dear reader, than have been dreamed of in our philosophy - or in our physics.

Nature is not embarrassed by difficulties of analysis. She avoids complication only in means. Nature seems to be proposed to do much with little: it is a principle that the development of physics constantly supports by new evidence.

It is interesting to note that the quantum-mechanical revolution was made by a virtually orphaned generation of scientists. Many members of the generation above them had been slaughtered in World War I. There simply weren't many senior scientists around to tell them they were crazy.

It is very desirable to have a word to express the Availability for work of the heat in a given magazine; a term for that possession, the waste of which is called Dissipation. Unfortunately the excellent word Entropy, which Clausius has introduced in this connexion, is applied by him to the negative of the idea we most naturally wish to express. It would only confuse the student if we were to endeavour to invent another term for our purpose. But the necessity for some such term will be obvious from the beautiful examples which follow. And we take the liberty of using the term Entropy in this altered sense ... The entropy of the universe tends continually to zero.

It was like bouncing tennis balls off a mystery piece of furniture and deducing, from the direction in which the balls ricocheted, whether it was a chair or a table or a Welsh dresser.

It was quite the most incredible event that has ever happened to me in my life. It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you. [Recalling in 1936 the discovery of the nucleus in 1909, when some alpha particles were observed instead of travelling through a very thin gold foil were seen to rebound backward, as if striking something much more massive than the particles themselves. He won the Nobel Prize in Chemistry for this discovery.]

It will reward enough for me if, by the publication of the present experiment, I have directed the attention of investigators to this subject, which still promises much for physical optics and appears to open a new field.

I was a young impressionable 13 year old hearing the pro-left and pro-right argument. So one day I would be convinced that one side was right. the other day I would be convinced the other side was right. And then I was getting confused. How can both of these things be true if they were contrary to each other. So I decided to focus on a field where the truth didn't dependent upon the eloquence of the speaker. The truth was absolute.

Love is a chemical reaction, But it cannot be fully understood or defined by science. And though a body cannot exist without a soul, It too cannot be fully understood or defined by science. Love is the most powerful form of energy, But science cannot decipher its elements. Yet the best cure for a sick soul is love, But even the most advanced physician Cannot prescribe it as medicine. INCOMPLETE SCIENCE by Suzy Kassem

Love was actually more like calculus or physics. What was the half-life of love? Did it have cosigns and slopes, or quarks that morphed from wave to particle faster than you could say, please don’t leave?

Mapenzi, kama ilivyo kwa vitu vyote hapa ulimwenguni, hayawezi kuwepo bila kujumuishwa na fizikia na kemia yake! Bila kemia hakuna mapenzi ya kudumu. Tamaa ya ngono kimsingi huanza pindi unapokutana na mtu. Tamaa hiyo huweza kukua na kuwa kitu kingine kadiri muda unavyokwenda lakini chanzo kinakuwepo toka siku ya kwanza mlipokutana. Kemikali inayosababisha tamaa ya ngono na hata kuikuza tamaa hiyo ni 'phenyl ethylamine' ('fino itholamine') au PEA ambayo ni kemikali ya mapenzi ndani ya ubongo. Husisimua watu na huongeza nguvu za kimwili (fizikia) na kihisia (kemia). Tamaa husababisha mtu azalishe PEA nyingi zaidi, kitu kinachosababisha kujisikia kizunguzungu (cha hisia za kimapenzi) na dalili zingine kama magoti kutetemeka, jasho kutoka viganjani na kutokutulia. Kemikali hii inapozalishwa kwa kiwango kikubwa, hutuma alamu ('signals') kutoka kwenye ubongo mpaka kwenye viungo vingine vya mwili na kutumika kama 'dopamine' au 'amphetamine' ambazo ni kemikali za ulevi ndani ya ubongo. Iwapo unajiuliza kwa nini wewe au mtu mwingine unavutiwa na mtu ambaye hamwendani kimapenzi, inaweza kuwa ni kwa sababu una kiwango kikubwa cha kemikali hizo kuliko mwenzako, kitu ambacho huzidi uwezo wa kutumia kichwa na kutoa maamuzi bora kulingana na akili ya kuzaliwa. Kwa jumla, mapenzi yote ya kweli uhitaji angalau kiwango kidogo cha PEA kwa wale wanaopendana. Cha msingi kukumbuka ni kwamba kemikali hizi huja kwa vituo, nikiwa simaanishi kwamba tamaa ya ngono hupotea pale mtu anapoelekea kwenye uhusiano wa kudumu. Lakini mambo hubadilika. Hatuwezi kuvumilia zile hisia kali kadiri tunavyozidi kusafiri kuelekea kwenye uhusiano wa kudumu na kwenye maisha ya pamoja yenye furaha. Katika uhusiano wenye afya hata hivyo matatizo hutokea hapa na pale. Chanzo cha Murphy na Debbie kupendana kilikuwa kemia zaidi kuliko fizikia. Kama hakuna kemia hakuna mapenzi.

Mars One has the power to show people around the globe what is possible if we just all work on one goal. No human has left Earth’s orbit since 1972 and no one ever ploughed beyond the moon into deep space. It’s finally time to inspire the world and make the next giant leap for mankind.

Maybe somewhere telepaths walked the Earth, but I wasn't one of them. In the process, I began to realize that the wondrous exploits of telepaths were probably impossible--at least without outside assistance. But in the years that followed, I also slowly learned another lesson: to fathom the greatest secrets in the universe, one did not need telepathic or superhuman abilities. One just had to have an open, determined, and curious mind. In particular, in order to understand whether the fantastic devices of science fiction are possible, you have to immerse yourself in advanced physics. To understand the precise point when the possible becomes the impossible, you have to appreciate and understand the laws of physics.

MUSIC OF THE UNIVERSE Without the orchestra of the universe, There would be no ether. And without its instrumentation By the ether, There would be no waves. And without any waves, There would be no sound. And without sound, There would be no music. And without music, There would be no life. And without a life force, There would be no matter. But it does not matter - Because what is matter, If there is no light?

Newton's laws specifically state that, while the gravity of a planet gets weaker and weaker the farthest from it you travel, there is no distance where the force of gravity reaches zero. The planet Jupiter, with its mighty gravitational field, bats out of harm's way many comets that would otherwise wreak havoc on the inner solar system. Jupiter acts as a gravitational shield for Earth, a burly big brother, allowing long (hundred-million-year) stretches of relative peace and quiet on Earth. Without Jupiter's protection, complex life would have a hard time becoming interestingly complex, always living at risk of extinction from a devastating impact.

No non-poetic account of reality can be complete.

It is said that Mathematics is the language of nature. If so, Physics is its poetry.

It's tough for magic to argue with physics, most of the time.

It will all stop someday, but not for billions of years. Many billions. Even the stars run down, you know. Entropy must increase.

Lots of wrongs eventually makes it right!

Many scientists have tried to make determinism and complementarity the basis of conclusions that seem to me weak and dangerous; for instance, they have used Heisenberg's uncertainty principle to bolster up human free will, though his principle, which applies exclusively to the behavior of electrons and is the direct result of microphysical measurement techniques, has nothing to do with human freedom of choice. It is far safer and wiser that the physicist remain on the solid ground of theoretical physics itself and eschew the shifting sands of philosophic extrapolations.

Mister Geoffrey, my experiment shows that the dynamo and the bulb are both working properly," I said. "So why won't the radio play?" "I don't know," he said. "Try connecting them here." He was pointing toward a socket on the radio labeled "AC," and when I shoved the wires inside, the radio came to life. We shouted with excitement. As I pedaled the bicycle, I could hear the great Billy Kaunda playing his happy music on Radio Two, and that made Geoffrey start to dance. "Keep pedaling," he said. "That's it, just keep pedaling." "Hey, I want to dance, too." "You'll have to wait your turn." Without realizing it, I'd just discovered the difference between alternating and direct current. Of course, I wouldn't know what this meant until much later. After a few minutes of pedaling this upside-down bike by hand, my arm grew tired and the radio slowly died. So I began thinking, "What can do the pedaling for us so Geoffrey and I can dance?

Newton's laws of physics can rarely be applied to the real world. There is more to life than cause and effect. Things just aren't that simple

Nobody knows how the stand of our knowledge about the atom would be without him. Personally, Bohr is one of the amiable colleagues I have met. He utters his opinions like one perpetually groping and never like one who believes himself to be in possession of the truth.

Nothing can be truly infinite at a single point in time, as it would have taken an infinite amount of time to have arisen; something may however, have infinite potential

Numbers, furthermore as archetypal structural constants of the collective unconscious, possess a dynamic, active aspect which is especially important to keep in mind. It is not what we can do with numbers but what they do to our consciousness that is essential.

Nowhere in Nature does one equal zero.

Number ... should not be understood solely as a construction of consciousness, but also as an archetype and thus as a constituent of nature both without and within.

One may characterize physics as the doctrine of the repeatable, be it a succession in time or the co-existence in space. The validity of physical theorems is founded on this repeatability.

One hundred thirty-seven is the inverse of something called the fine-structure constant. ...The most remarkable thing about this remarkable number is that it is dimension-free. ...Werner Heisenberg once proclaimed that all the quandaries of quantum mechanics would shrivel up when 137 was finally explained.

One must divide one's time between politics and equations. But our equations are much more important to me, because politics is for the present, while our equations are for eternity.

One of my friends compared me to Bruce Banner, due to my work with radiation and human health. So I looked up Bruce Banner and this is what I found: Banner, a physicist, is sarcastic and seemingly very self-assured when he first appears in Incredible Hulk #1, but is also emotionally withdrawn in most fashions...Banner is considered one of the greatest scientific minds on Earth, possessing "a mind so brilliant it cannot be measured on any known intelligence test." He holds expertise in biology, chemistry, engineering, physiology, and nuclear physics.

One day, I hope we will know the answers to all these questions. But there are other challenges, other big questions on the planet which must be answered, and these will also need a new generation who are interested and engaged, and have an understanding of science. How will we feed an ever-growing population? Provide clean water, generate renewable energy, prevent and cure disease and slow down global climate change? I hope that science and technology will provide the answers to these questions, but it will take people, human beings with knowledge and understanding, to implement these solutions. Let us fight for every woman and every man to have the opportunity to live healthy, secure lives, full of opportunity and love. We are all time travellers, journeying together into the future. But let us work together to make that future a place we want to visit. Be brave, be curious, be determined, overcome the odds. It can be done.

[On the practical applications of particle physics research with the Large Hadron Collider.] Sometimes the public says, 'What's in it for Numero Uno? Am I going to get better television reception? Am I going to get better Internet reception?' Well, in some sense, yeah. ... All the wonders of quantum physics were learned basically from looking at atom-smasher technology. ... But let me let you in on a secret: We physicists are not driven to do this because of better color television. ... That's a spin-off. We do this because we want to understand our role and our place in the universe.

Only three of the naturally occurring elements were manufactured in the big bang. The rest were forged in the high-temperature hearts and explosive remains of dying stars, enabling subsequent generations of star systems to incorporate this enrichment, forming planets and, in our case, people. For many, the Periodic Table of Chemical Elements is a forgotten oddity—a chart of boxes filled with mysterious, cryptic letters last encountered on the wall of high school chemistry class. As the organizing principle for the chemical behavior of all known and yet-to-be-discovered elements in the universe, the table instead ought to be a cultural icon, a testimony to the enterprise of science as an international human adventure conducted in laboratories, particle accelerators, and on the frontier of the cosmos itself.

On September 14, 2015, the LIGO gravitational-wave detectors (built by a 1,000-person project that Rai and I and Ronald Drever co-founded, and Barry Barish organised, assembled and led) registered their first gravitational waves. By comparing the wave patterns with predictions from computer simulations, our team concluded that the waves were produced when two heavy black holes, 1.3 billion light years from Earth, collided. This was the beginning of gravitational-wave astronomy. Our team had achieved, for gravitational waves, what Galileo achieved for electromagnetic waves. I am confident that, over the coming several decades, the next generation of gravitational-wave astronomers will use these waves not only to test Stephen’s laws of black hole physics, but also to detect and monitor gravitational waves from the singular birth of our universe, and thereby test Stephen’s and others’ ideas about how our universe came to be. During our glorious year of 1974–5, while I was dithering over gravitational waves, and Stephen was leading our merged group in black hole research, Stephen himself had an insight even more radical than his discovery of Hawking radiation. He gave a compelling, almost airtight proof that, when a black hole forms and “and then subsequently evaporates away completely by emitting radiation, the information that went into the black hole cannot come back out. Information is inevitably lost.

Only three constants are significant for star formation: the gravitational constant, the fine structure constant, and a constant that governs nuclear reaction rates.

On September 14, 2015, the LIGO gravitational-wave detectors (built by a 1,000-person project that Rai and I and Ronald Drever co-founded, and Barry Barish organised, assembled and led) registered their first gravitational waves. By comparing the wave patterns with predictions from computer simulations, our team concluded that the waves were produced when two heavy black holes, 1.3 billion light years from Earth, collided. This was the beginning of gravitational-wave astronomy. Our team had achieved, for gravitational waves, what Galileo achieved for electromagnetic waves. I am confident that, over the coming several decades, the next generation of gravitational-wave astronomers will use these waves not only to test Stephen’s laws of black hole physics, but also to detect and monitor gravitational waves from the singular birth of our universe, and thereby test Stephen’s and others’ ideas about how our universe came to be.

Oppenheimer’s theorizing was so startlingly original — so far in advance of the corroborating observations and so far off the beaten track of astrophysical research — that his colleagues’ ignorance cost him the recognition he deserved.

Sanayah returned to work after a week. She said she had to come back for her clients. 'Ali didn't like it, but that was her choice. She decided that even if Ami were not supportive, the aggressive client was a rarity, a remote risk. Ten-meter hills of brownest humus and blackest ash stood between Sanayah and her return to work. The slopes were at their critical angle of repose so she was afraid to step on them; they might cascade down on her.

Perhaps there are many "nows" of varying duration, depending on just what it is we are doing. We must face up to the fact that, at least in the case of humans, the subject experiencing subjective time is not a perfect, structureless observer, but a complex, multilayered, multifaceted psyche. Different levels of our consciousness may experience time in quite different ways. This is evidently the case in terms of response time. You have probably had the slightly unnerving experience of jumping at the sound of a telephone a moment or two before you actually hear it ring. The shrill noise induces a reflex response through the nervous system much faster than the time it takes to create the conscious experience of the sound. It is fashionable to attribute certain qualities, such as speech ability, to the left side of the brain, whereas others, such as musical appreciation, belong to processes occurring on the right side. But why should both hemispheres experience a common time? And why should the subconscious use the same mental clock as the conscious?

Planck...and Bohr...have invented systems containing electrons of which the motion produces no effect upon external charges...[N]ot only [is this] inconsistent with the accepted laws of electromagnetism, but I may add, is logically objectionable, for that state of motion which produces no physical effect whatsoever may better be called a state of rest.

Primary causes are unknown to us; but are subject to simple and constant laws, which may be discovered by observation, the study of them being the object of natural philosophy. Heat, like gravity, penetrates every substance of the universe, its rays occupy all parts of space. The object of our work is to set forth the mathematical laws which this element obeys. The theory of heat will hereafter form one of the most important branches of general physics.

Pure analysis puts at our disposal a multitude of procedures whose infallibility it guarantees; it opens to us a thousand different ways on which we can embark in all confidence; we are assured of meeting there no obstacles; but of all these ways, which will lead us most promptly to our goal? Who shall tell us which to choose? We need a faculty which makes us see the end from afar, and intuition is this faculty. It is necessary to the explorer for choosing his route; it is not less so to the one following his trail who wants to know why he chose it.

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.

...quantum problems unseat many classical ideas about matter, causality, and change that biologists use, and that disruption in turn entails radical revisions to the ideas about the mechanism in evolution, in ways we don't yet acknowledge.

Quantum jumping is the process by which a person envisions some desired result or state of being that is different from the existing situation—and by clearly observing that possibility and supplying sufficient energy, makes a leap into that alternate reality.

Realizing its fundamental importance in understanding spectral lines, in atomic physics and in the theory of how light and electrons interact, quantum electrodynamics, Pauli and Heisenberg were determined to derive it from quantum theory rather than introducing it from the start. They believed that if they could find a version of quantum electrodynamics capable of producing the fine structure constant, it would not contain the infinities that marred their theories.