Einstein’s theory of general relativity suggests that our universe originated in a Big Bang. But black holes, and their gravitational forces, challenge the limits of Einstein’s work.
Bright, flickering galaxies called quasars were thought to pose a problem for our understanding of the cosmos – but new research shows Einstein was right yet again.
Particle physics has failed to find some of the evidence physicists were hoping for.
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Our two best theories of nature, quantum mechanics and general relativity, are incompatible with each other in many ways – leaving physicists to dig deeper.
Time gets a little strange as you approach the speed of light.
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Cutting-edge theories of physics suggest time may not be real – but even if they’re right, life can still go on as usual.
Experiments at the Large Hadron Collider in Europe, like the ATLAS calorimeter seen here, are providing more accurate measurements of fundamental particles.
Maximilien Brice
Physicists know a lot about the most fundamental properties of the universe, but they certainly don’t know everything. 2021 was a big year for physics – what was learned and what’s coming next?
An artist’s impression of the Double Pulsar system in which the two pulsars orbit each other every 2.5 hours and send out high-energy beams that sweep across the sky.
Image credit: John Rowe Animations/CSIRO
Such a mission could be developed soon, allowing astrophysicists to take selfies of the solar system and use the Sun’s gravity as a lens to peer deep into space.
Gravity feels like it’s pulling everything toward Earth, but why?
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Gravity is something every person on Earth intuitively understands: It is what keeps you on the ground. But how come gravity pulls down, rather than pushes up? Einstein came up with the answer.
If humanity wants to travel between stars, people are going to need to travel faster than light. New research suggests that it might be possible to build warp drives and beat the galactic speed limit.
Field theory describes the universe as energy flowing along unending lines. With this perspective, it is possible to define a new fundamental building block of matter.
Roger Penrose helped resurrect Einstein’s general theory of relativity, and Reinhard Genzel and Andrea Ghez showed there was a black hole in the middle of our galaxy.
This image of the NGC 1398 galaxy, which is located in the Fornax cluster, was taken with the Dark Energy Camera.
Dark Energy Survey/Flickr