Theory Of Gravity Quotes & Sayings

Superstring theories provide a framework in which the force of gravity may be united with the other three forces in nature: the weak, electromagnetic and strong forces. Recent progress has shown that the most promising superstring theories follow from a single theory. For the last generation, physicists have studied five string theories and one close cousin. Recently it has become clear that these five or six theories are different limiting cases of one theory which, though still scarcely understood, is the candidate for superunification of the forces of nature. — Edward Witten

We can summarize electricity, magnetism and gravity into equations one inch long, and that's the power of field theory. And so I said to myself: I will create a field theory of strings. And when I did it one day, it was incredible, realizing that on a sheet of paper I can write down an equation which summarized almost all physical knowledge. — Michio Kaku

Einstein wrestled with a problem back before we even knew the universe was expanding, and he was looking for a way to keep the universe from collapsing. And so he discovered, in his theory of gravity, something like this dark energy - he called it a cosmological constant - could play this role, pushing things away. — Adam Riess

The French need a thrashing. If the Prussians win, the centralisation of the state power will be useful for the centralisation of the German working class. German predominance would also transfer the centre of gravity of the workers' movement in Western Europe from France to Germany, and one has only to compare the movement in the two countries from 1866 till now to see that the German working class is superior to the French both theoretically and organisationally. Their predominance over the French on the world stage would also mean the predominance of our theory over Proudhon's, etc. — Karl Marx

...a useful coorective to the triumphalism of some scientists. For example, Maddox went out of his way to emphasise the provisional nature of much physics - he referred to black holes as 'putative' only, to the search for theories of everything as 'the embodiment of a belief, even a hope' and stated that the reason why the quantum gravity project is 'becalmed' right now is because 'the problem to be solved is not yet fully understood' and that the idea that the universe began with a Big Bang 'will be found to be false'. — Peter Watson

We find, counterintuitively, that a small population correlates with shorter humans, and a larger population correlates with taller humans. This only makes sense in light of the FSM theory of gravity. With more people on earth today, there are fewer Noodly Appendages to go around, so we each receive less touching - pushing down toward the earth - and thus, with less force downward, we're taller. — Bobby Henderson

Tokyo is a model of that serial big-bang theory of the universe. It explodes at five P.M. and people matter is hurled to the suburbs, but by 5 A.M. the people-matter gravity reasserts itself, and everything surges back toward the center, where mass densens for the next explosion. — David Mitchell

Evolution is just a theory? Well, so is gravity and I don't see you jumping out of buildings. — Richard Dawkins

What the string theorists do is arguably physics. It deals with the physical world. They're attempting to make a consistent theory that explains the interactions we see among particles and gravity as well. That's certainly physics, but it's a kind of physics that is not yet testable. — Sheldon Lee Glashow

Over the last three decades, theorists have proposed at least a dozen new approaches. Each approach is motivated by a compelling hypothesis, but none has so far succeeded. In the realm of particle physics, these include Technicolor, preon models, and supersymmetry. In the realm of spacetime, they include twistor theory, causal sets, supergravity, dynamical triangulations, and loop quantum gravity. Some of these ideas are as exotic as they sound. — Lee Smolin

Both loop quantum gravity and string theory assert that there is an atomic structure to space. In the next two chapters we shall see that loop quantum gravity in fact gives a rather detailed picture of that atomic structure. The picture of the atomic structure one gets from string theory is presently incomplete but, as we shall see in Chapter 11, it is still impossible in string theory to avoid the conclusion that there must be an atomic structure to space and time. In Chapter 13 we shall discover that both pictures of the atomic structure of space can be used to explain the entropy and temperature of black holes. — Lee Smolin

His new idea was published that month in what became yet another seminal Einstein paper, "Cosmological Considerations in the General Theory of Relativity."9 On the surface, it did indeed seem to be based on a crazy notion: space has no borders because gravity bends it back on itself. Einstein — Walter Isaacson

I imagine Einstein had a full sensational experience when he formulated his Theory of Relativity. He might have envisioned (inner) the sun and its weight in space as a billiard ball resting on a sheet. While he looked (outer) down at his notes, he might have remembered (inner) a past conversation with his good friend, the mathematician Marcel Grossmann, about mathematics and gravity. He might have felt (outer) tightness in his gut as he waited for an eclipse to take place, which would prove his theory right or wrong. — Sarah Wood Vallely

I am using the word theory as a scientist means it: a set of ideas so well established by observations and physical models that it is essentially indistinguishable from fact. That is different from the colloquial use that means "guess." To a scientist, you can bet your life on a theory. Remember, gravity is "just a theory" too. — Philip Plait

Even today, I am in total awe of the following wondrous chain of ideas and interconnections. Guided throughout by principles of symmetry, Einstein first showed that acceleration and gravity are really two sides of the same coin. He then expanded the concept to demonstrate that gravity merely reflects the geometry of spacetime. The instruments he used to develop the theory were Riemann's non-Euclidean geometries-precisely the same geometries used by Felix Klein to show that geometry is in fact a manifestation of group theory (because every geometry is defined by its symmetries-the objects it leaves unchanged). Isn't this amazing? — Mario Livio

In essence, String Theory describes space and time, matter and energy, gravity and light, indeed all of God's creation ... as music. — Roy H. Williams

Three of the four forces (excluding gravity) are therefore united by quantum theory, giving us unification without geometry, which appears to contradict the theme of this book and everything we have considered so far. — Michio Kaku

Technically you need the extra dimensions. At first people didn't like them too much, but they've got a big benefit, which is that the ability of string theory to describe all the elementary particles and their forces along with gravity depends on using the extra dimensions. — Edward Witten

We're going to need a definitive quantum theory of gravity, which is part of a grand unified theory - it's the main missing piece. — Kip Thorne

Some claim evolution is just a theory. As if it were merely an opinion. The theory of evolution, like the theory of gravity, is a scientific fact. Evolution really happened. Accepting our kinship with all life on Earth is not only solid science. In my view, it's also a soaring spiritual experience. — Neil DeGrasse Tyson

I always found it satisfying that gravity was described by Einstein's geometric theory of general relativity. — Antony Garrett Lisi

The supposed astronomical proofs of the theory [of relativity], as cited and claimed by Einstein, do not exist. He is a confusionist. The Einstein theory is a fallacy. The theory that ether does not exist, and that gravity is not a force but a property of space can only be described as a crazy vagary, a disgrace to our age. — Charles Lane Poor

The theory of evolution, like the theory of gravity, is a scientific fact. — Neil DeGrasse Tyson

The evolution of higher and of lower forms of life is as well and as soundly established as the eternal hills. It has long since ceased to be a theory; it is a law of Nature as universal in living things as is the law of gravitation in material things and in the motions of the heavenly spheres. — Henry Fairfield Osborn

By the time I began my study of physics in the early 1970s, the idea of unifying gravity with the other forces was as dead as the idea of continuous matter. It was a lesson in the foolishness of once great thinkers. Ernst Mach didn't believe in atoms, James Clerk Maxwell believed in the aether, and Albert Einstein searched for a unified-field theory. Life is tough. — Lee Smolin

So we may now pose a question which could be answered only if we have a quantum theory of gravity. What is the nature of the information trapped in a quantum black hole? Keep this in mind as we go ahead and explore the different approaches to quantum gravity, for a good test of a theory of quantum gravity is how well it is able to answer this question. — Lee Smolin

There was a long history of speculation that in quantum gravity, unlike Einstein's classical theory, it might be possible for the topology of spacetime to change. — Edward Witten

String theory is based on the simple idea that all the four forces of the universe: gravity, the electromagnetic force and the two nuclear forces, can be viewed, as music. — Michio Kaku

One of the most exciting things about dark energy is that it seems to live at the very nexus of two of our most successful theories of physics: quantum mechanics, which explains the physics of the small, and Einstein's Theory of General Relativity, which explains the physics of the large, including gravity. — Adam Riess

So, Einstein's theory of gravity is a theory of causal structure. It tells us that the essence of spacetime is causal structure and that the motion of matter is a consequence of alterations in the network of causal relations. What is left out from the notion of causal structure is any measure of quantity or scale. — Lee Smolin

One readon why it has taken so long to construct a quantum theory of gravity is that all previous quantum theories were background dependent. It proved rather challenging to construct a background independent quantum theory, in which the mathematical structure of the quantum theory made no mention of points, except when identified through networks of relationships. The problem of how to construct a quantum theoretic description of a world in which space and time are nothing but networks of relationships was solved over the last 15 years of the twentieth century. The theory that resulted is loop quantum gravity, which is one of our three roads. — Lee Smolin

Because both quantum theory and Einstein's theory of gravity are united in ten-dimensional space, we expect that the question of time travel will be settled decisively by the hyperspace theory. As in the case of wormholes and dimensional windows, the final chapter will be written when we incorporate the full power of the hyperspace theory. — Michio Kaku

In the classical theory of gravity, which is based on real space-time, there are only two possible ways the universe can behave: either it has existed for an infinite time, or else it had a beginning at a singularity at some finite time in the past. — Stephen Hawking

Evolution is a fact. It is the best explanation of what is known from observations. It's a theory as powerful as the theory of gravity. — Donald Johanson

The most famous story about gravity involves Isaac Newton and an apple that supposedly fell on his head, inspiring him to concoct his theory of universal gravitation. (It's mostly famous because Newton himself couldn't stop telling it later in life, in an unnecessary attempt to add some extra juice to his reputation as a genius.) — Sean Carroll

No one talks about it. No one talks about them at all. "The Ancients prefer discretion," Mom once told me. But some say it's because they're so freakish we'd drop dead of fright. Others say they're too attractive, too tempting. I prefer this theory. — Melissa West

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. — Joseph Fourier

Kepler's laws, although not rigidly true, are sufficiently near to the truth to have led to the discovery of the law of attraction of the bodies of the solar system. The deviation from complete accuracy is due to the facts, that the planets are not of inappreciable mass, that, in consequence, they disturb each other's orbits about the Sun, and, by their action on the Sun itself, cause the periodic time of each to be shorter than if the Sun were a fixed body, in the subduplicate ratio of the mass of the Sun to the sum of the masses of the Sun and Planet; these errors are appreciable although very small, since the mass of the largest of the planets, Jupiter, is less than 1/1000th of the Sun's mass. — Isaac Newton

Whether it is a falling man or an orbiting satellite, the effect of inertia is to create an apparent upward force that depends on the mass of the object. It is the same force we feel when riding in a car that goes around a tight curve. This inertial effect is equal and opposite to gravity and therefore cancels the pull of gravity. In physicist language, the "gravitational mass" and "inertial mass" are equal. This is not a tautology, as Ambrose Bierce thought, but a recognition that the pull of gravity is proportional to the inertia of the object being pulled. Einstein called this the "Principle of Equivalence", and it became the basis for his new theory of gravity that he called the general theory of relativity. — Rodney A. Brooks

How odd that Americans, and not just their presidents, have come to think of their Constitution as something separable from the government it's supposed to constitute. In theory, it should be as binding on rulers as the laws of physics are on engineers who design bridges; in practice, its axioms have become mere options. Of course engineers don't have to take oaths to respect the law of gravity; reality gives them no choice. Politics, as we see, makes all human laws optional for politicians. — Joseph Sobran

Every string theory that's been written down says the speed of light is universal. But other ideas about quantum gravity predict the speed of light has actually increased. — Lee Smolin

It must have appeared almost as improbable to the earlier geologists, that the laws of earthquakes should one day throw light on the origin of mountains, as it must to the first astronomers, that the fall of an apple should assist in explaining the motions of the moon. — Charles Lyell

As we discussed in Chapter 7, we physicists still haven't found a mathematical structure that can describe all aspects of reality, including gravity, but so far, there's no indication that string theory or any of the other most actively pursued candidates for such a description are any less mathematical than quantum field theory. — Max Tegmark

Attachment exerted an invisible but powerful pull on the child, just as heavenly bodies are connected by gravitational forces. But unlike gravity, attachment makes its presence known by a negative inverse square law: the further the attached person is from their secure base, the greater the pull of attachment. The 'elastic band' which constitutes the attachment bond is slack and imperceptible in the presence of a secure base. If the secure base becomes unreliable or the limits of exploration are reached, the bond tugs at the heartstrings. — Jeremy Holmes

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