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Einsteinian physics

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Gravitational waves

Einstein for Everyone. Einstein for Everyone Nullarbor Press 2007revisions 2008, 2010, 2011, 2012, 2013 Copyright 2007, 2008, 2010, 2011, 2012, 2013 John D.

Einstein for Everyone

Norton Published by Nullarbor Press, 500 Fifth Avenue, Pittsburgh, Pennsylvania 15260 with offices in Liberty Ave., Pittsburgh, Pennsylvania, 15222 All Rights Reserved John D. An advanced sequel is planned in this series:Einstein for Almost Everyone 2 4 6 8 9 7 5 3 1 ePrinted in the United States of America no trees were harmed web*bookTM This book is a continuing work in progress. January 1, 2015. Preface For over a decade I have taught an introductory, undergraduate class, "Einstein for Everyone," at the University of Pittsburgh to anyone interested enough to walk through door.

With each new offering of the course, I had the chance to find out what content worked and which of my ever so clever pedagogical inventions were failures. At the same time, my lecture notes have evolved. This text owes a lot to many. I i i.


Physical laws. Flash simulation, Animation, Illustration, Picture, Diagram. General relativity. Big bang. The Scale of the Universe. The Scale of the Universe 2. Time. On the Origin of Gravity and the Laws of Newton. Integral challenges physics beyond Einstein. Integral challenges physics beyond Einstein Gamma-ray burst 30 June 2011 ESA’s Integral gamma-ray observatory has provided results that will dramatically affect the search for physics beyond Einstein.

Integral challenges physics beyond Einstein

It has shown that any underlying quantum ‘graininess’ of space must be at much smaller scales than previously predicted. Einstein’s General Theory of Relativity describes the properties of gravity and assumes that space is a smooth, continuous fabric. One of the great concerns of modern physics is to marry these two concepts into a single theory of quantum gravity. Now, Integral has placed stringent new limits on the size of these quantum ‘grains’ in space, showing them to be much smaller than some quantum gravity ideas would suggest. According to calculations, the tiny grains would affect the way that gamma rays travel through space. Einstein field equations. The Einstein field equations (EFE) or Einstein - Hilbert equations are a set of 10 equations in Albert Einstein's general theory of relativity which describe the fundamental interaction of gravitation as a result of spacetime being curved by matter and energy.[1] First published by Einstein in 1915[2] as a tensor equation, the EFE equate local spacetime curvature (expressed by the Einstein tensor) with the local energy and momentum within that spacetime (expressed by the stress–energy tensor).[3] As well as obeying local energy-momentum conservation, the EFE reduce to Newton's law of gravitation where the gravitational field is weak and velocities are much less than the speed of light.[4] Exact solutions for the EFE can only be found under simplifying assumptions such as symmetry.

Einstein field equations

Special classes of exact solutions are most often studied as they model many gravitational phenomena, such as rotating black holes and the expanding universe. Mathematical form[edit] where. Chronology of Gravitational Physics and Relativity. Friedmann equations. And pressure .

Friedmann equations

The equations for negative spatial curvature were given by Friedmann in 1924.[2] Assumptions[edit] The Friedmann equations start with the simplifying assumption that the universe is spatially homogeneous and isotropic, i.e. the Cosmological Principle; empirically, this is justified on scales larger than ~100 Mpc. Physics and Astronomy. Epic study confirms Einstein on space-time vortex around Earth. Einstein was right: There is a four-dimensional space-time vortex around Earth, and the spin of Earth does twist space-time. That’s according to NASA, in an announcement made 52 years after scientists first imagined how to test Einstein’s theory on space-time – before the technology to test it had even been invented. NASA announced confirmation of the four-D space-time vortex around Earth on May 4, 2011. What does it mean? As Einstein suggested in his general theory of relativity, published in 1916, gravity can be described as the motion of objects following curved lines in space – or rather space-time , as Einstein more accurately depicted it.

The curved lines are caused by the presence of a mass, for example our Earth or sun. Gravitation. Gravitation, or gravity, is a natural phenomenon by which all physical bodies attract each other.


It is most commonly recognized and experienced as the agent that gives weight to physical objects, and causes physical objects to fall toward the ground when dropped from a height. During the grand unification epoch, gravity separated from the electronuclear force. Gravity is the weakest of the four fundamental forces, and appears to have unlimited range (unlike the strong or weak force).