Did abstract mathematics, such as Pythagoras’s theorem, exist before the big bang?
Simon McLeish Lechlade, Gloucestershire, UK
The notion of the existence of mathematical ideas is a complex one.
One way to look at it is that mathematics is about the use of logical thought to derive information, often information about other mathematical ideas. The use of objective logic should mean that mathematical ideas are eternal: they have always been, and always will be.
Astronomers have discovered a black hole with a mass about 33 times greater than that of our sun, the biggest one known in the Milky Way aside from the supermassive black hole lurking at the center of our galaxy.
The newly identified black hole is located about 2,000 light-years from Earth — relatively close in cosmic terms — in the constellation Aquila, and has a companion star orbiting it, researchers said on Tuesday. A light year is the distance light travels in a year, 5.9 trillion miles.
Black holes are extraordinarily dense objects with gravity so strong that not even light can escape, making it difficult to spot them. This one was identified through observations made in the European Space Agency’s Gaia mission, which is creating a huge stellar census, because it caused a wobbling motion in its companion star. Data from the European Southern Observatory’s Chile-based Very Large Telescope and other ground-based observatories were used to verify the black hole’s mass.
The study found that black holes in old, inactive galaxies have grown significantly in mass over the last 9 billion years, suggesting they interact with the expanding universe.
If black hole mass development happened only through accretion or merging, the masses of these black holes would be anticipated to remain relatively constant. However, if black holes gain mass by interacting with the expanding cosmos, these passively developing elliptical galaxies might disclose this process.
The researchers discovered that the further back in time they examined, the smaller the black holes were in mass compared to their masses today. These changes were significant: black holes were 7 to 20 times bigger now than they were 9 billion years ago, leading the researchers to hypothesize cosmic coupling.
Such decoupling of dark and normal matter has been seen before, most famously in the Bullet Cluster. In that collision, the hot gas can be seen clearly lagging behind the dark matter after the two galaxy clusters shot through each other. The situation that took place in MACS J0018.5+1626 (referred to subsequently as MACS J0018.5) is similar, but the orientation of the merger is rotated, roughly 90 degrees relative to that of the Bullet Cluster.
In other words, one of the massive clusters in MACS J0018.5 is flying nearly straight toward Earth while the other one is rushing away. That orientation gave researchers a unique vantagepoint from which to, for the first time, map out the velocity of both the dark matter and normal matter and elucidate how they decouple from each other during a galaxy cluster collision.
“With the Bullet Cluster, it’s like we are sitting in a grandstand watching a car race and are able to capture beautiful snapshots of the cars moving from left to right on the straightaway,” says Sayers. “In our case, it’s more like we are on the straightaway with a radar gun, standing in front of a car as it comes at us and are able to obtain its speed.”
Researchers have created a quantum tornado in superfluid helium to simulate black hole conditions, advancing our understanding of black hole physics and the behavior of quantum fields in curved spacetimes, culminating in a unique art and science exhibition.
Scientists have, for the first time, created a giant quantum vortex in superfluid helium to mimic a black hole. This breakthrough has enabled them to observe in greater detail how analog black holes behave and interact with their surroundings.
Research led by the University of Nottingham, in collaboration with King’s College London and Newcastle University, has created a novel experimental platform: a quantum tornado. They have created a giant swirling vortex within superfluid helium that is chilled to the lowest possible temperatures. Through the observation of minute wave dynamics on the superfluid’s surface, the research team has shown that these quantum tornados mimic gravitational conditions near rotating black holes. The research has been published today in Nature.
New research may have found a link between supermassive black holes and dark matter particles which might solve an issue which has irked astrophysicists for decades: the “final parsec problem.”
Last year, an international team of researchers discovered a background “hum” of gravitational waves. They hypothesised that this background signal is emanating from millions of merging pairs of supermassive black hole.
Supermassive black holes are hundreds of thousands to billions of times larger than our Sun.
When a large star runs out of fuel, its core collapses into a dense object, ejecting the remaining gas outward in an event known as a supernova. What’s left are largely neutron stars and black holes. And now Hubble appears to have observed a supernova blink out, implying that it captured the instant a black hole took over.
What makes this occurrence unique is that the formation of a black hole was not foreseen. Normally, when a star of this size reaches the end of its life, it explodes in a massive event called a supernova. Instead, it appears that this star chose to go out quietly.
A recent discovery by NASA’s James Webb Space Telescope (JWST) confirmed that luminous, very red objects previously detected in the early universe upend conventional thinking about the origins and evolution of galaxies and their supermassive black holes.
An international team, led by Penn State researchers, using the NIRSpec instrument aboard JWST as part of the RUBIES survey identified three mysterious objects in the early universe, about 600–800 million years after the Big Bang, when the universe was only 5% of its current age. They announced the discovery today June 27 in Astrophysical Journal Letters.
The team studied spectral measurements, or intensity of different wavelengths of light emitted from the objects. Their analysis found signatures of “old” stars, hundreds of millions of years old, far older than expected in a young universe.
Quantum field theory (QFT) was a crucial step in our understanding of the fundamental nature of the Universe. In its current form, however, it is poorly suited for describing composite particles, made up of multiple interacting elementary particles. Today, QFT for hadrons has been largely replaced with quantum chromodynamics, but this new framework still leaves many gaps in our understanding, particularly surrounding the nature of strong nuclear force and the origins of dark matter and dark energy. Through a new algebraic formulation of QFT, Dr Abdulaziz Alhaidari at the Saudi Center for Theoretical Physics hopes that these issues could finally be addressed.
The emergence of quantum field theory (QFT) was one of the most important developments in modern physics. By combining the theories of special relativity, quantum mechanics, and the interaction of matter via classical field equations, it provides robust explanations for many fundamental phenomena, including interactions between charged particles via the exchange of photons.
Still, QFT in its current form is far from flawless. Among its limitations is its inability to produce a precise description of composite particles such as hadrons, which are made up of multiple interacting elementary particles that are confined (cannot be observed in isolation). Since these particles possess an internal structure, the nature of these interactions becomes far more difficult to define mathematically, stretching the descriptive abilities of QFT beyond its limits.