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updated Mon. May 7, 2018

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Third, inference to the best explanation is not just a passionless move in some deduction game. Einstein was not led to his theories of special and general relativity through attention to data alone, as if following some experimental breadcrumbs. His theories were the offspring of his imagination as much as ...
He is perhaps best known for his subsequent work unifying different flavours of string theory, an attempt to move beyond general relativity to a “theory of everything” that unifies all of nature's forces. In a less formal award, a poll of physicists attending a cosmology conference the same year saw him dubbed ...

This feat—a revolution in physics that would supplant Isaac Newton's law of universal gravitation and result in Einstein's theory of general relativity—would require some new ideas. Fortunately, Einstein's friend and collaborator Marcel Grossmann swooped in like a waiter bearing an exotic, appetizing ...
OSWEGO — The SUNY Oswego planetarium will examine “General Relativity, Generally” at 7 p.m. every Sunday during May. Using SUNY Oswego's planetarium, host Richard Frieman of the atmospheric and geological sciences department will explore the fundamentals of general relativity as proposed by ...
When the theory of relativity appeared in the early 1900s, it upended centuries of science and gave physicists a new understanding of space and time. Isaac Newton saw space and time as fixed, but in the new picture provided by special relativity and general relativity they were fluid and malleable.
But according to general relativity, gravity is the result of massive objects like the sun and planets warping spacetime. The warping caused by the sun, Einstein realized, would affect the rotation of each planet's orbit slightly and would be most noticeable for Mercury, since it is closest to the sun. But a smaller ...

His dissertation, “Stability and instability results in general relativity,” provides the first rigorous proof of the instability of Anti-de Sitter (AdS) spacetime in the presence of matter. “While the instability of AdS spacetime in the absence of matter remains a challenging open problem, the ideas and techniques ...
Alongside quantum mechanics, a second modern, or post-1900, physical principle that Einstein called “general relativity” emerged. This theory provided a unified description of gravity, describing natural phenomena on a much larger scale than quantum mechanics at the level of orbiting planets and ...
“The existence of quantum [fluctuations] due to gravitational fields has been known since the late 1970s,” explains Carballo-Rubio. But physicists didn't know how to take this effect into account in collapsing stars. Carballo-Rubio derived equations that combine general relativity and quantum mechanics in a ...
Since the formulation of Einstein's theory of general relativity in 1915, every theoretical physicist has been dreaming of reconciling our understanding of the infinitely small world of atoms and particles with that of the infinitely large scale of the cosmos. While the latter is effectively described by Einstein's ...
According to a straightforward interpretation of general relativity, the Big Bang wasn't the start of 'everything'. Taking Einstein's famous equations at face value and making as few assumptions as possible, a team of researchers has rewound the clock on our Universe to find it wouldn't lead to a stopping ...
Now, though, we know that this precession is actually due to the effects of general relativity, as the Sun's mass deforms space-time around it. Mercury rotates on its axis with nearly no tilt whatsoever, meaning the planet experiences no seasons and there are places at the poles where sunlight never touches, ...
In addition to general relativity, Hawking was a leader in the search for extraterrestrial life. He served as a board member of the Breakthrough Starshot Initiative, which aims to visit our nearest neighboring star, Alpha Centauri. I was a member of the advisory committee, and now my students characterize the ...
"He dove into the chasm between quantum theory and general relativity and came back with a pearl," says Adam Riess, Nobel Laureate in Physics for his work providing evidence of accelerated universal expansion and a Bloomberg Distinguished Professor of astronomy and physics at Johns Hopkins ...
Stephen Hawking's biggest accomplishment shone through both his physics work and his outreach to the public, bridging gaps between things that once seemed incompatible. Whether he was demonstrating that black holes did indeed radiate material or that popular culture could embrace the mysteries of ...
Hawking made his reputation with his study of “singularities,” unimaginable objects predicted by Einstein's theory of general relativity. When a star with several times the mass of our sun exhausts its nuclear fuel, it collapses, its matter crushing together with such force that it forms a singularity, an infinitely ...
And that means that black holes eventually evaporate and even explode. The finding was so important because, first off, it provided a clue that one day, quantum mechanics and general relativity could be united into one grand theory. In other words, if quantum mechanics and relativity could come together ...

In 1965, when Dr. Hawking was 23, the British mathematician Roger Penrose proved that if Einstein's theory of gravity, general relativity, was correct there is a point of infinite density — a singularity — at the center of a black hole. In 1970, building on work in Dr. Hawking's doctoral dissertation, he and Dr.
General relativity was meant to supplant Newtonian gravity. This meant it had to explain all the same physical phenomena Newton's equations could, plus other phenomena that Newton's equations couldn't. Yet in mid-1913, Einstein convinced himself, incorrectly, that his new theory couldn't account for ...
According to general relativity, light affected by a strong gravitational field will get stretched out, or redshifted. The orbit will also shift, ever so slightly changing trajectory. As S0-2 moves in for its closest approach at 17 light-hours away from the centre of the galaxy (about four times the distance between the ...
Astronomers are so eager for this close approach because it will serve as yet another stringent test of Einstein's Theory of General Relativity. But, until last week, there was a slight sense of unease in the air as astronomers suspected S0-2 was a binary star system like many other S-stars. This would have ...
“General relativity has been the staple of gravitational understanding for 100 years,” says Katie Chamberlain, a physics student at Montana State University. “We have to rule out the potential for other existing theories to come in and replace [it].” Many alternative theories of gravity are out there, designed to ...
Over the last year, however, mathematicians have brought the mathematics of general relativity into sharper focus. Two groups have come up with proofs related to an important problem in general relativity called the black hole stability conjecture. Their work proves that Einstein's equations match a physical ...
... an alternative explanation of the anomaly. In three preprints uploaded to the arXiv server, the duo calculate that effects due the curvature of space-time could result in an increase in the measured value of the magnetic moment. This effect of general relativity is related to the gravitational field of the Earth.
To date, Einstein's theory of general relativity may have stood up to test after test, but that doesn't mean it's infallible - or that scientists should stop trying to test it. Every time the theory holds, we learn something valuable about the Universe.
An idea for an experiment that could unite the stubborn fields of quantum mechanics and general relativity has been given new life by two groups of physicists from the UK. The fact that quantum theory doesn't play well with gravity is a massive stumbling block in physics, one that has long eluded some of ...
He created his theory of general relativity to account for this: gravity is a manifestation of the warping of spacetime caused by massive bodies like the sun. Mercury's orbit shows this warping most clearly—and, indeed, before Einstein's work, scientists were long puzzled by its strangeness, even attributing it ...
General Relativity is, currently, the best theory to explain gravitational phenomena. Published by Albert Einstein in 1915, the theory found agreement with known astronomical observations, and it stated novel predictions that have been confirmed with great accuracy. Such predictions are actually ...
However, new research by Vitor Cardoso from the University of Lisbon, Portugal, and colleagues [1] suggests that this predictability of the laws of physics can fail in general relativity. The researchers find that it might be possible for a star that undergoes gravitational collapse to form a black hole containing a ...
Patsyk stated that “Einstein's equations of general relativity determine, among other issues, the evolution of electromagnetic waves in curved space. It turns out that the evolution of electromagnetic waves in curved space according to Einstein's equations is equivalent to the propagation of electromagnetic ...
We all know how successful Einstein was as a scientist, with his ideas reshaping our understanding of the universe and becoming a part of our everyday thinking and culture. But for all his accomplishments, like transforming our conception of space and time with his theory of general relativity, the Nobel ...
Despite huge research efforts, the relation between the two big theories of the 20th century – General Relativity and Quantum Mechanics is still not clearly understood. The idea that all interactions are fundamentally quantum, albeit extremely successful with all non-gravitational interactions, seems to fail in ...
Editor's note: Both Albert Einstein's Theory of General Relativity and Isaac Newton's Law of Universal Gravitation explain gravity through science. In the language of science, the word "law" describes an analytic statement. It gives us a formula that tells us what things will do. While laws rarely change, ...
... show the jets' streams gradually change direction in the sky, or precess, as a result of space-time being dragged into the rotation of the black hole. This behavior aligns with Albert Einstein's predictions about extreme gravity near rotating black holes, published in his famous theory of general relativity.
"Previous attempts considered statements of general relativity and quantum mechanics to be applicable to the same world. My approach separates the two—quantum mechanics allows for a quantum state to be a 'superposition' of many classical worlds; statements of quantum mechanics apply to the ...
A pair of researchers have uncovered a potential bridge between general relativity and quantum mechanics — the two preeminent physics theories — and it could force physicists to rethink the very nature of space and time. Albert Einstein's theory of general relativity describes gravity as a geometric ...
Shortly after Albert Einstein wrote his equations for General Relativity, which describe gravity, he included an "antigravity" factor called the "cosmological constant" to balance gravitational attraction and produce a static universe. But Einstein later called the cosmological constant his greatest mistake.
Shortly after Albert Einstein wrote his equations for General Relativity, which describe gravity, he included an “antigravity” factor called the “cosmological constant” to balance gravitational attraction and produce a static universe. But Einstein later called the cosmological constant his greatest mistake.
Although the laws of general relativity and quantum mechanics work exceptionally well in their own spheres, some of the rules that govern one area don't work in the other, and vice-versa. For instance, Relativity explains the gravitational force as it relates to bodies on Earth or in space. But it falls apart on ...
His “strong cosmic censorship” conjecture states that there is some mechanism within general relativity – a censor – that prohibits the appearance of Cauchy horizons. In the case of a charged black hole, he calculated that even the slightest perturbation in the initial conditions of the imploding star destroys ...
Two separate groups in the UK; Chiara Marletto and Vlatko Vedral at the University of Oxford, and a team led by Sougato Bose from University College London, have proposed experiments that may for the first time reveal a link between the theories of quantum mechanics and general relativity. Within their ...
According to general relativity, an object's composition has no impact on how gravity pulls on it: Earth's gravity accelerates a sphere of iron at the same rate as a sphere of lead. That's what's known as the weak equivalence principle. A slew of experiments have confirmed that principle — beginning with ...
Einstein's theory of general relativity therefore describes gravity as not just a force, but geometry – it is a consequence of how matter warps spacetime. Unlike Newton's theory, general relativity correctly describes the changing orbit of Mercury by taking into account the disturbances of spacetime caused by ...
Now, a team of researchers at the California Institute of Technology led by Sean Carroll has suggested that this interpretation can explain away inconsistencies pertaining to black holes. They say that general relativity is upheld within each single possible world, while information is preserved across the ...
Einstein's theory of gravity, known as general relativity, marks a fundamental break in our conception of the universe. Whereas Newton envisaged gravity as a force of attr action between two objects in empty space, relativity instead tells us that gravity is a distortion of space (and time) itself. The theory was ...
LYON, France—Partial results of the experiment conducted aboard Europe's Microscope mini-satellite have confirmed with unprecedented precision a key principle in the theory of general relativity postulated by Albert Einstein, French space agency CNES announced earlier this .
Einstein's theory of relativity usually covers two interrelated theories: special relativity and general relativity. This theory was proposed in 1905 and depicts the relationship between space and time. Special relativity brought in ideas like the speed of light being a universal speed limit and the passage of time ...
While the theory of general relativity has succeeded in describing the force of gravity over cosmological distances, it has not been tested in the microscopic realm. This is the subject of quantum gravity theory, which suggests the existence of gravitons, massless particles that remain theoretical at the moment ...
That question requires a quick dive into Albert Einstein's general relativity, or theory of gravity — the same theory that predicted gravitational waves a century ago. Einstein overthrew Isaac Newton's idea of “absolute time.” Newton thought time marched onward everywhere at an identical pace — regardless ...
Scientists still don't know how to combine general relativity with quantum mechanics, the physics of the very small. “The two theories seems to be very different, and people would like to merge these two theories,” Rodrigues says. But some attempts to do that predict violations of the equivalence principle on ...


 

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