Lifeboat Foundation

Quantum gravity is a theoretical attempt to reconcile general relativity and the quantum field theories of particle physics. The theory holds that space and time are both quantized in a way that quantum field theory doesn’t account for. Attempts to find evidence in support of the theory have focused on the gravitational effects of black holes. Now, some are using the data collected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) project that has now detected two instances of gravitational waves from the collision of black holes. And there are hints that the data has the evidence the researchers are looking for.

But Afshordi’s idea overthrows what physicists believed they knew about black holes. In Albert Einstein’s theory of general relativity, the event horizon of a black hole – the surface beyond which there is no escape – is insubstantial. Nothing special happens upon crossing it, just that there is no turning around later. If Afshordi is right, however, the inside of the black hole past the event horizon no longer exists. Instead, a Planck-length away from where the horizon would have been, quantum gravitational effects become large, and space-time fluctuations go wild. (The Planck length is a minuscule distance: about 10^-35 metres, or 10^-20 times the diameter of a proton.) It’s a complete break with relativity.

When he heard of the LIGO results, Afshordi realised that his so-far entirely theoretical idea could be observationally tested. If event horizons are different than expected, the gravitational-wave bursts from merging black holes should be different, too. Events picked up by LIGO should have echoes, a subtle but clear signal that would indicate a departure from standard physics. Such a discovery would be a breakthrough in the long search for a quantum theory of gravity. ‘If they confirm it, I should probably book a ticket to Stockholm,’ Afshordi said, laughing.

Continue reading “Do ripples in space-time herald a new theory of gravity?” »

The past few years have been incredible for physics discoveries. Scientists spotted the Higgs boson, a particle they’d been hunting for almost 50 years, in 2012, and gravitational waves, which were theorized 100 years ago, in 2016. This year, they’re slated to take a picture of a black hole. So, thought some theorists, why not combine all of the craziest physics ideas into one, a physics turducken? What if we, say, try to spot the dark matter radiating off of black holes through their gravitational waves?

Meanwhile, the Hubble image offered a clue about what dislodged the black hole from its galaxy’s centre. The host galaxy bore faint, arc-shaped features called tidal tales, which are produced by the gravitational tug-of-war that takes place when two galaxies collide. This suggested that galaxy 3C 186 had recently merged with another system, and perhaps their black holes merged too.

What happened next, scientists can only theorize. Chiaberge and his colleagues suggest that as the galaxies collided, their black holes began to circle each other, flinging out gravity waves “like water from a lawn sprinkler,” as NASA described it. If the black holes had unequal masses and spin rates, they might have sent more gravitational waves in one direction than the other. When the collision was complete, the newly merged black hole would have then recoiled from the strongest gravitational waves, shooting off in the opposite direction.

“This asymmetry depends on properties such as the mass and the relative orientation of the back holes’ rotation axes before the merger,” Colin Norman of STScI and Johns Hopkins University, a co-author on the paper, said in the NASA news release. “That’s why these objects are so rare.”

Theoretical physicists have put forward a new hypothesis that aims to connect the world of visible physics to the hidden forces of our Universe: what if there’s a portal that bridges the gap between the standard model to dark matter and dark energy?

The idea is that the reason we struggle to understand things such as dark matter and dark energy isn’t because they don’t exist — it’s because we’ve been oblivious to a portal through which regular particles and these ‘dark particles’ interact. And it’s something that could be tested experimentally.

The idea of portals in the Universe might sound pretty crazy, but let’s be clear for a second: we’re talking portals on the quantum, teeny-tiny scale here — nothing that you could drive a spacecraft through.

Continue reading “Theoretical Physicists Suggest There’s a Portal Linking the Standard Model to Dark Physics” »

Astronomers have uncovered a supermassive black hole that has been propelled out of the center of a distant galaxy by what could be the awesome power of gravitational waves.

Though there have been several other suspected, similarly booted black holes elsewhere, none has been confirmed so far. Astronomers think this object, detected by NASA’s Hubble Space Telescope, is a very strong case. Weighing more than 1 billion suns, the rogue black hole is the most massive black hole ever detected to have been kicked out of its central home.

Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole. The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two hefty black holes at the center of the host galaxy.

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A new computer simulation helps explain the existence of puzzling supermassive black holes observed in the early universe. The simulation is based on a computer code used to understand the coupling of radiation and certain materials. “Supermassive black holes have a speed limit that governs how fast and how large they can grow,” said Joseph Smidt of the Theoretical Design Division at Los Alamos National Laboratory, “The relatively recent discovery of supermassive black holes in the early development of the universe raised a fundamental question, how did they get so big so fast?”

Using computer codes developed at Los Alamos for modeling the interaction of matter and radiation related to the Lab’s stockpile stewardship mission, Smidt and colleagues created a simulation of collapsing stars that resulted in supermassive black holes forming in less time than expected, cosmologically speaking, in the first billion years of the universe. “It turns out that while supermassive black holes have a growth speed limit, certain types of massive stars do not,” said Smidt. “We asked, what if we could find a place where stars could grow much faster, perhaps to the size of many thousands of suns; could they form supermassive black holes in less time?” A video about the discovery: https://www.youtube.com/watch?v=LD4xECbHx_I&feature=youtu.be

Of all the laws of physics, this is arguably one of the strangest — scientists have discovered that the forces controlling the behaviour of a black hole’s event horizon are also at play in superfluid helium, an extraordinary liquid that flows without friction.

This entanglement area law has now been observed at both the vast scale of black holes and the atomic scale of cold helium, and could be the key to finally establishing the long sought-after quantum theory of gravity — the solution to one of the deepest problems in theoretical physics today.

Continue reading “A Bizarre Physics Law Is Making Superfluid Helium Behave Like an Actual Black Hole” »

A team of scientists has discovered that a law controlling the bizarre behavior of black holes out in space—is also true for cold helium atoms that can be studied in laboratories. “It’s called an entanglement area law,” says Adrian Del Maestro, a physicist at the University of Vermont who co-led the research. That this law appears at both the vast scale of outer space and at the tiny scale of atoms, “is weird,” Del Maestro says, “and it points to a deeper understanding of reality.”

A central goal that modern physicists share is finding a single theory that can explain the entire Universe and unite the forces of nature.

The standard model, for example, leaves dark matter, dark energy, and even gravity out of the picture — meaning that it really only accounts for a very small percentage of what makes up the Universe.

Continue reading “Why String Theory Could Be the Key to Uncovering the ‘Theory of Everything’” »