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The new theory, developed by physicists at Aalto University, describes gravity in a way that’s compatible with the Standard Model of particle physics, opening the door to an improved understanding of how the Universe began. The Standard Model of particle physics describes electromagnetic, weak, and strong interactions, which are three of the four known fundamental forces of nature. The unification of the fourth interaction, gravity, with the Standard Model has been challenging due to incompatibilities of the underlying theories — general relativity and quantum field theory. While quantum field theory utilizes compact, finite-dimensional symmetries associated with the internal degrees of...

If you've been following my channel for a really long time, you might remember that some years ago I made a video about whether faster-than-light travel is possible. I was trying to explain why the arguments saying it's impossible are inconclusive and we shouldn't throw out the possibility too quickly, but I'm afraid I didn't make my case very well. This video is a second attempt. Hopefully this time it'll come across more clearly!I Think Faster Than Light Travel is Possible. Here's Why. | 23:46Sabine Hossenfelder | 943K subscribers | 1,569,919 views | April 8, 2023

For decades physicists have tried to rectify the Standard Model of Particle Physics, which is great at describing the behavior of particles, interactions, and quantum processes on the micro scale, with gravity...the Standard Model, as it is currently constructed, fails to account for gravity at this extremely small scale. ...a number of mathematical models have been proposed that would unify these disparate phenomena, including something called string theory [and] a number of these models feature elements that can be tested in a lab setting. One is known as the Pauli exclusion principle. Pauli exclusion basically means that no two electrons...

Avi Loeb, bestselling author and the former chair of Harvard’s astronomy department, penned an op-ed in Scientific American this week positing that the universe could have been formed in a lab by an “advanced technological civilization.”….

Last year, scientists detected the most energetic gamma ray burst we've ever seen. A distant galaxy spat out a colossal flare in the range of a trillion electron volts (TeV), providing invaluable new insight into the physics of these incredibly energetic events. That was pretty amazing on its own - but now astrophysicists have used the burst to perform a new, precise test of the theory of general relativity. And - quelle surprise! - this test found that the speed of light is constant in a vacuum. Relativity, once again, has passed with flying colours. The test hinges on a...

Gravitational waves are caused by calamitous events in the Universe. Neutron stars that finally merge after circling each other for a long time can create them, and so can two black holes that collide with each other. But sometimes there's a burst of gravitational waves that doesn't have a clear cause. One such burst was detected by LIGO/VIRGO on January 14, and it came from the same region of sky that hosts the star Betelgeuse. Yeah, Betelgeuse, aka Alpha Orionis. The star that has been exhibiting some dimming behaviour recently, and is expected to go supernova at some point in...

Earth's gravitational wave observatories -- which hunt for ripples in the fabric of space-time -- just picked up something weird. The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors recorded an unknown or unanticipated "burst" of gravitational waves on Jan. 14. The gravitational waves we've detected so far usually relate to extreme cosmic events, like two black holes colliding or neutron stars finally merging after being caught in a death spiral. Burst gravitational waves have not been detected before and scientists hypothesize they may be linked to phenomena such as supernova or gamma ray bursts, producing a tiny "pop" when...

The concept of time travel has always captured the imagination of physicists and laypersons alike. But is it really possible? Of course it is. We're doing it right now, aren't we? We are all traveling into the future one second at a time. But that was not what you were thinking. Can we travel much further into the future? Absolutely. If we could travel close to the speed of light, or in the proximity of a black hole, time would slow down enabling us to travel arbitrarily far into the future. The really interesting question is whether we can travel...

The Universe we know and love — with Einstein’s General Relativity as our theory of gravity and quantum field theories of the other three forces — has a problem that we don’t often talk about: it’s incomplete, and we know it. Einstein’s theory on its own is just fine, describing how matter-and-energy relate to the curvature of space-and-time. Quantum field theories on their own are fine as well, describing how particles interact and experience forces. Normally, the quantum field theory calculations are done in flat space, where spacetime isn’t curved. We can do them in the curved space described by...

John Forbes Nash Jr. was a mathematical genius who had his life chronicled in the movie A Beautiful Mind. One of Nash’s colleagues says that just days before he died in a New York taxi cab accident, he had discussed his latest and possibly most brilliant discovery to date. Mathematician Cédric Villan says that Nash told him that he had replaced Einstein’s Theory of Relativity and that the new equation would further explain quantum gravity. The Daily Mail reports that on May 20, 2015, just three days before the tax cab accident that would take his life, Nash spoke to...

The road uniting quantum field theory and general relativity -- the two great theories of modern physics -- has been impassable for 80 years. Could a tool from condensed matter physics finally help map the way?

December 7, 2004 String Theory, at 20, Explains It All (or Not) By DENNIS OVERBYE SPEN, Colo. - They all laughed 20 years ago. It was then that a physicist named John Schwarz jumped up on the stage during a cabaret at the physics center here and began babbling about having discovered a theory that could explain everything. By prearrangement men in white suits swooped in and carried away Dr. Schwarz, then a little-known researcher at the California Institute of Technology.Only a few of the laughing audience members knew that Dr. Schwarz was not entirely joking. He and his...

The Future According to Professor Paul Davies "Scientists have no doubt whatever that it is possible to build a time machine to visit the future". Since the publication of Einstein’s Special Theory of Relativity in 1905, few, if any, scientists would dispute that time travel to the future is perfectly possible. According to this theory, time runs slower for a moving person than for someone who is stationary. This has been proven by experiments using very accurate atomic clocks. In theory, a traveller on a super high-speed rocket ship could fly far out into the Universe and then come back...