Best 538 quotes in «physics quotes» category

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.

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 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 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is sarcastic and seemingly very self-assured when he first appears in Incredible Hulk #1, but is also emotionally withdrawn in most fashions...Banner is considered one of the greatest scientific minds on Earth, possessing "a mind so brilliant it cannot be measured on any known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.

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

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.

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.

[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.

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.

Our image is here and will for ever stay, and there is comfort in knowing that the memory of our lives will always be there, traveling among the stars.

People have always wanted answers to the big questions. Where did we come from? How did the universe begin? What is the meaning and design behind it all? Is there anyone out there? The creation accounts of the past now seem less relevant and credible. They have been replaced by a variety of what can only be called superstitions, ranging from New Age to Star Trek. But real science can be far stranger than science fiction, and much more satisfying. I am a scientist. And a scientist with a deep fascination with physics, cosmology, the universe and the future of humanity. I was brought up by my parents to have an unwavering curiosity and, like my father, to research and try to answer the many questions that science asks us. I have spent my life travelling across the universe, inside my mind. Through theoretical physics, I have sought to answer some of the great questions. At one point, I thought I would see the end of physics as we know it, but now I think the wonder of discovery will continue long after I am gone. We are close to some of these answers, but we are not there yet.

Philosophy has an image problem. Philosophers are thought to be mystics, religious figures, bullshit artists—anything divorced from reality... Why is philosophy held in such contempt by many physicists? ... one part of the answer probably lies in the split between the two major branches of modern Western philosophy, Analytic and Continental philosophy. Continental philosophers tend to be much more suspicious of scientific claims about knowledge and truth than are their analytic colleagues. Yet the distinction between the two kinds of philosophy is not apparent from a distance—most scientists have never heard of the analytic-Continental divide. So, given that most of the highly visible philosophers in the public sphere today are Continental, and given the attitude that some (not all) Continental philosophers have toward science, it’s not terribly surprising that scientists often have disdain for all philosophers, and sometimes even think that they can do philosophy better than the philosophers can.

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.

Plato considered the golden section proportion the most binding of all mathematical relations, making it the key to the physics of the cosmos.

Please beware," came his reply, "There are a lot of people who believe that just because we don't have an explanation for something, it's quantum mechanics.

Physicists have yet to find anything capable of exceeding our known speed of light. The Tao cannot be named, and so I say there is one thing that out-paces all things: we call it “thought.” I can fill a room a with light before I’m anywhere near the switch.

Physicists love this number not just because it is dimensionless, but also because it is a combination of three fundamental constants of nature. Why do these constants come together to make the particular number 1/137.036 and not some other number?

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.

Privacy, in fact, was almost as desirable for physics as it was for sex.

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.

QED [quantum electrodynamics] reduces ... "all of chemistry and most of physics," to one basic interaction, the fundamental coupling of a photon to electric charge. The strength of this coupling remains, however, as a pure number, the so-called fine-structure constant, which is a parameter of QED that QED itself is powerless to predict.

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 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.

Rather than being handed down from above, like the Ten Commandments, they [the laws of physics] look exactly as they should look if they were not handed down from anywhere...they follow from the very lack of structure at the earliest moment.

...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.

Relationships are physics. Time transforms things- it has to, because the change from me to we means clearing away the fortifications you'r put up around your old personality. Living with Susannah made me feel as if I started riding Einstein's famous theoretical bus. Here's my understanding of that difficult idea, nutshelled: if you're riding a magic Greyhound, equipped for light-speed travel, you'll actually live though less time than will any pedestrians whom the bus passes by. So, for a neighbor on the street with a stopwatch, the superfast bus will take two hours to travel from Point A to Point B. But where you're on that Greyhound, and looking at the wipe of the world out those rhomboidial coach windows, the same trip will take just under twenty-four minutes. Your neighbor, stopwatch under thumb, will have aged eighty-six percent more than you have. It's hard to fathom. But I think it's exactly what adult relationships do to us: on the outside, years pass, lives change. But inside, it's just a day that repeats. You and your partner age at the same clip; it seems not time has gone by. Only when you look up from your relationship- when you step off the bus, feel the ground under your shoes- do you sense the sly, soft absurdity of romance physics.

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.

Real Martial Arts is Mathematics, Physics, Poetry; Meditation in Action

Science is opposed to theological dogmas because science is founded on fact. To me, the universe is simply a great machine which never came into being and never will end. The human being is no exception to the natural order. Man, like the universe, is a machine. Nothing enters our minds or determines our actions which is not directly or indirectly a response to stimuli beating upon our sense organs from without. Owing to the similarity of our construction and the sameness of our environment, we respond in like manner to similar stimuli, and from the concordance of our reactions, understanding is born. In the course of ages, mechanisms of infinite complexity are developed, but what we call 'soul' or 'spirit,' is nothing more than the sum of the functionings of the body. When this functioning ceases, the 'soul' or the 'spirit' ceases likewise. I expressed these ideas long before the behaviorists, led by Pavlov in Russia and by Watson in the United States, proclaimed their new psychology. This apparently mechanistic conception is not antagonistic to an ethical conception of life.

Research is turning the unknown into reality.

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.

Scientists have no proof that life was not the result of an act of creation, but they are driven by the nature of their profession to seek explanations for the origin of life that lie within the boundaries of natural law.

See, those who wield the primordial forces of creation have a long-running grudge with physics.

Robert Oppenheimer used to tell of the pioneer mysteries of building reliable Geiger counters that had low background noise. Among his friends, he said, there were two schools of thought. One school firmly held that the final step before one sealed off the Geiger tube was to peel a banana and wave the skin three times, sharply to the left. The other school was equally confident that success would follow if one waved the banana peel twice to the left and then, once, smartly to the right. (My counters were unbelievably bad because I didn't use either of these techniques.)

Same as you, Arthur. I hitched a ride. After all, with a degree in maths and another in astrophysics it was either that or back to the dole queue on Monday. Sorry I missed the Wednesday lunch date, but I was in a black hole all morning.

Science began with a gadget and a trick. The gadget was the wheel; the trick was fire. We have come a long way from the two-wheel cart to the round-the-world transport plane, or from the sparking flint to man-made nuclear fission. Yet I wonder whether the inhabitants of Hiroshima were more aware of the evolution of science than ancient man facing an on-storming battle chariot. It isn't physics that will make this a better life, nor chemistry, nor sociology. Physics may be used to atom-bomb a nation and chemistry may be used to poison a city and sociology has been used to drive people and classes against classes. Science is only an instrument, no more than a stick or fire or water that can be used to lean on or light or refresh, and also can be used to flail or burn or drown. Knowledge without morals is a beast on the loose.

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.

Some segments of this book may be rough going. That's the nature of real science. It requires thought. Sometimes deep thought. But thinking can be rewarding. You can just skip the rough parts, or you can struggle to understand.

Since ancient times artists and architects have seen in the golden mean the most aesthetically satisfying geometric ratio.

Since every piece of matter in the Universe is in some way affected by every other piece of matter in the Universe, it is in theory possible to extrapolate the whole of creation - every sun, every planet, their orbits, their composition and their economic and social history from, say, one small piece of fairy cake.

Some astrophysicists have convinced themselves that the fifth significant figure of the fine structure constant has changed over the past ten billion years.

So many of the properties of matter, especially when in the gaseous form, can be deduced from the hypothesis that their minute parts are in rapid motion, the velocity increasing with the temperature, that the precise nature of this motion becomes a subject of rational curiosity. Daniel Bernoulli, John Herapath, Joule, Krönig, Clausius, &c., have shewn that the relations between pressure, temperature and density in a perfect gas can be explained by supposing the particles move with uniform velocity in straight lines, striking against the sides of the containing vessel and thus producing pressure. (1860)

Some people, including Hawking, think that we may be able to understand the big bang or the big crunch (in particular, whether time has a beginning or an end at these events) when we have a satisfactory quantum theory of gravitation.

Some recent work by E. Fermi and L. Szilárd, which has been communicated to me in manuscript, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation seem to call for watchfulness and, if necessary, quick action on the part of the Administration. ... This new phenomenon would also lead to the construction of bombs, and it is conceivable—though much less certain—that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat or exploded in a port, might well destroy the whole port altogether with some of the surrounding territory. However, such bombs might well prove to be too heavy for transportation by air.

Spheres are indeed fertile theoretical tools that help us gain insight into all manner of astrophysical problems. But one should not be a sphere-zealot. I am reminded of the half-serious joke about how to increase milk production on a farm: An expert in animal husbandry might say, "Consider the role of the cow's diet..." An engineer might say, "Consider the design of the milking machines..." But it's the astrophysicist who says, "Consider a spherical cow...

Stay upbeat and keep your head held high. There is no end to the power of positive thinking. I AM looking forward to all the wealth, success, and abundance speeding my way!

That day, the great mind in neuroscience Michael A. Persinger, who is now a good friend of mine, made me realize that it was no other field of Science but Neuroscience that held the key to solving the quintessential problems of consciousness. He coaxed me into the science of the neurons and the rest as you know is history. Without Persinger, Naskar and Neuroscience would never have been linked together. Imbued with new knowledge, confidence and excessive curiosity, I officially turned my attention to one of the loftiest goals of modern science - understanding the biological nature of the human mind. That day on, I officially got into the world of Neuroscience.