31 jan. 2017
learning physics
gravity & relativity.
https://www.newscientist.com/round-up/instant-expert-general-relativity/
(Image: XMM-Newton/ESA/NASA)
learning physics
gravity & relativity.
https://www.newscientist.com/round-up/instant-expert-general-relativity/
Instant Expert: General relativity
(Image: XMM-Newton/ESA/NASA)
Welcome
to the first in our new monthly "Instant Expert" series.
This month, astrophysicist Pedro Ferreira of the University of Oxford offers a concise, up-to-the minute summary of what a well-informed person should know about general relativity.
Find out more about Instant Expert
Pedro
Ferreira is professor of astrophysics at the University of Oxford. He
works on the origin of large-scale structures in the universe, on the
general theory of relativity and on the nature of dark matter and dark
energy
This month, astrophysicist Pedro Ferreira of the University of Oxford offers a concise, up-to-the minute summary of what a well-informed person should know about general relativity.
Find out more about Instant Expert
ABOUT THE AUTHOR
Pedro
Ferreira is professor of astrophysics at the University of Oxford. He
works on the origin of large-scale structures in the universe, on the
general theory of relativity and on the nature of dark matter and dark
energy1. PAST, PRESENT AND FUTURE
Albert
Einstein's general theory of relativity is one of the towering
achievements of 20th-century physics.
Published in 1916, it explains that what we perceive as the force of gravity in fact arises from the curvature of space and time.
Einstein proposed that objects such as the sun and the Earth change this geometry.
In the presence of matter and energy it can evolve, stretch and warp, forming ridges, mountains and valleys that cause bodies moving through it to zigzag and curve.
So although Earth appears to be pulled towards the sun by gravity, there is no such force. It is simply the geometry of space-time around the sun telling Earth how to move.
The general theory of relativity has far-reaching consequences.
It not only explains the motion of the planets; it can also describe the history and expansion of the universe, the physics of black holes and the bending of light from distant stars and galaxies.
Einstein’s general theory of relativity is an undoubted work of genius.
Yet 100 years on, it still raises many questions – and physicists continue to look for something better.
(Image: Quibe)
Click here to find out more.
Published in 1916, it explains that what we perceive as the force of gravity in fact arises from the curvature of space and time.
Einstein proposed that objects such as the sun and the Earth change this geometry.
In the presence of matter and energy it can evolve, stretch and warp, forming ridges, mountains and valleys that cause bodies moving through it to zigzag and curve.
So although Earth appears to be pulled towards the sun by gravity, there is no such force. It is simply the geometry of space-time around the sun telling Earth how to move.
The general theory of relativity has far-reaching consequences.
It not only explains the motion of the planets; it can also describe the history and expansion of the universe, the physics of black holes and the bending of light from distant stars and galaxies.
General relativity at 100: Einstein’s unfinished masterpiece
Einstein’s general theory of relativity is an undoubted work of genius.Yet 100 years on, it still raises many questions – and physicists continue to look for something better.
(Image: Quibe)
Click here to find out more.
EINSTEIN'S INSIGHT
General relativity: Einstein’s insight
How Einstein moved from his 1905 special theory of relativity to general relativity a decade later, via a brainwave he had at his day job2. HOW GENERAL RELATIVITY SHAPES OUR UNIVERSE
Einstein's
general theory of relativity has revealed that the universe is an
extreme place. We now know it was hot and dense and has been expanding
for the past 13.7 billion years.
It is also populated with incredibly warped regions of space-time called black holes that trap anything falling within their clutches.
It is also populated with incredibly warped regions of space-time called black holes that trap anything falling within their clutches.
