Latest news with #EnriqueGaztanaga
Yahoo
a day ago
- Science
- Yahoo
We May Be Living in a Black Hole from a Parent Universe, Here's Why That Matters
A group of physicists just put forward a theory that could shake our understanding of where we came from, and where we're going. According to their new model, our universe may have originated not in a singular explosion, but as a bounce from inside a black hole formed in a previous 'parent' universe. That's right: you could be living inside a black hole. This bold claim comes from a paper led by Professor Enrique Gaztanaga of the Institute of Cosmos Sciences in Barcelona published in Physical Review D. He and his team argue that the Big Bang wasn't the beginning of everything, but rather a cosmic transition point in a cycle that never really starts or ends. The idea centers around the Pauli exclusion principle, which is a well-known quantum rule that prevents identical particles from occupying the same space. Gaztanaga believes this principle prevents the total collapse of matter in a dying universe, forcing it to "bounce" and expand again, forming a new universe inside what we would call a black hole. Here's the twist: unlike many speculative physics models, this one doesn't require exotic particles or untestable fields. The bounce, according to the paper, occurs naturally within Einstein's framework of general relativity. Even the two phases of expansion, what we call inflation and dark energy, can be explained by the dynamics of the bounce itself. What makes this model especially compelling is that it's testable. The team predicts a slightly curved universe and a small but measurable cosmological constant. These could potentially be confirmed by upcoming missions like the European Space Agency's Arrakihs satellite. If proven correct, it would upend one of the most deeply held beliefs in modern physics—that the universe began with a singularity. Instead, we'd be part of an endless chain of universes, each born from the collapse of the last. 'We are not witnessing the birth of everything from nothing,' Gaztanaga writes. 'But rather the continuation of a cosmic cycle.' And if he's right, the Big Bang wasn't our beginning. It was just our turn. We May Be Living in a Black Hole from a Parent Universe, Here's Why That Matters first appeared on Men's Journal on Jun 9, 2025
Yahoo
3 days ago
- Science
- Yahoo
Scientists Calculate That the Entire Big Bang Must Have Taken Place Inside a Black Hole
The standard model of cosmology may be the best explanation we've got for why the universe is the way it is and how it all came to be. But it's not the only explanation. Enter black hole cosmology. It's a radical idea which proposes that the Big Bang — the rapid unraveling of an infinitely dense point, believed to have given birth to the cosmos as we know it — actually took place in a black hole, which itself formed inside a larger "parent" universe. Ergo, all of us — and every star, planet, galaxy, and internet rando — are living inside one of these mysterious singularities. Enrique Gaztanaga, lead author of a new study published in the journal Physical Review D and a professor at the Institute of Cosmology and Gravitation at the University of Portsmouth, isn't the first to propose this controversial idea. But his team's research offers a new model for imagining how this hypothetical scenario took place. "Our calculations suggest the Big Bang was not the start of everything, but rather the outcome of a gravitational crunch or collapse that formed a very massive black hole — followed by a bounce inside it," Gaztanaga wrote in an essay for The Conversation. Certainly, there are a lot of holes you could poke in the standard model. Why is there more matter than anti-matter, when the universe should be uniform? Why did the universe undergo a period of "cosmic inflation" in which it expanded at faster than light speeds, then stopped? And why does its present day rate of expansion appear to be different depending on how we measure it? Gaztanaga's main gripe seems to be with our current understanding of a singularity. To him, the idea of the universe starting as a point of infinite density is immensely unsatisfying. "This is not just a technical glitch; it's a deep theoretical problem that suggests we don't really understand the beginning at all," he wrote. Gaztanaga also takes aim at other convenient cosmological constructions like dark energy, which is intended to explain why the universe's expansion is mysteriously accelerating. This hypothetical force is thought to make up 68 percent of the universe but is completely unobservable, leaving room for different-minded scientists to call its existence into question. Rethinking singularities could neatly resolve many of these conundrums. We return to Gaztanaga's paper. "Gravitational collapse does not have to end in a singularity," he wrote for The Conversation. "Our maths show that as we approach the potential singularity, the size of the universe changes as a (hyperbolic) function of cosmic time." This is a bold claim. The consensus is that gravitational collapse — like a star imploding into a black hole — must result in an infinitely dense singularity. What Gaztanaga is arguing happens instead is that the collapse not only halt short of completely crushing the matter, but reverses course — a "bounce," in his terminology. "What emerges on the other side of the bounce is a universe remarkably like our own," Gaztanaga explains. "Even more surprisingly, the rebound naturally produces the two separate phases of accelerated expansion — inflation and dark energy — driven not by a hypothetical fields but by the physics of the bounce itself." It's a fascinating explanation, but there's a lot that remains to be proved. It relies on discounting some very well-established physics behind singularities. The standard model may not be perfect, but it's the standard for a reason. It'll take a lot more to dethrone it, and Gaztanaga is optimistic that future missions like the European Space Agency's ARRAKIHS, which will study invisible structures of dark matter to test the model, could reveal the answers we're looking for. More on cosmology: Astronomers Confused to Discover That a Bunch of Nearby Galaxies Are Pointing Directly at Us
Daily Mail
6 days ago
- General
- Daily Mail
Scientists claim the Big Bang theory is WRONG - as they reveal how the universe really began
For decades, almost every scientist has agreed that the universe began in an enormous explosion known as the Big Bang. But one group of researchers now controversially claims that everything we think about the birth of the cosmos might be wrong. In a radical new research paper, Professor Enrique Gaztanaga, of the University of Portsmouth and his co-authors have proposed a new theory they call the 'Black Hole Universe'. They claim that the universe was formed by a gravitational crunch, forming a massive black hole that then 'bounced' outwards. Professor Gaztanaga claims this theory can explain everything we know about the structure of the universe without the need for any exotic elements such as dark energy. Importantly, the theory also predicts that space should be slightly curved rather than completely flat as the Big Bang model suggests. This is something that current NASA missions such as Euclid may soon be able to confirm, possibly offering a strong hint that the Black Hole Universe theory is correct. However, the Black Hole Universe theory may also have some staggeringly strange consequences for humanity's place in the universe. According to the Big Bang theory, before the universe as we know it came to be, all the matter that currently exists was packed into an infinitely dense point called a 'singularity'. From this point, around 13.8 billion years ago, the universe exploded outwards in an extraordinarily rapid phase of expansion known as cosmic inflation. The shape etched into matter as that initial explosion cooled laid out the patterns that would become stars, galaxies, and even larger structures like galactic superclusters. Since then, as observations from space telescopes like Hubble have shown, the universe has been expanding outwards at a steadily accelerating rate. This so-called 'standard model of cosmology' works well for explaining many big questions such as why galaxies are where they are, but Professor Gaztanaga wasn't satisfied. The problem was that the standard model only works well when scientists make some big assumptions about how the world might work. For example, to explain why the universe is still accelerating scientists have been forced to add mysterious 'dark energy' to the picture - a force that is pushing against gravity but has never been directly observed. So, instead of looking at the expanding universe and trying to work out where it comes from, the researchers looked at what happens when matter collapses in on itself. The Black Hole Universe Theory The Black Hole Universe theory claims that the cosmos did not begin with the Big Bang. The Big Bang theory says the universe exploded outwards from a single, infinitely dense point. The Black Hole Universe suggests that the universe we now see started after a cloud of matter collapsed into a black hole. At a certain point that black hole couldn't compress any more and started to bounce outwards. Our entire universe is inside this black hole, which is nested inside a larger host universe. When large stars collapse in on themselves, they form black holes - objects so dense that not even light can escape their gravitational pull. According to the standard view proposed by Stephen Hawking and British physicist Roger Penrose, when this happens gravity squishes matter down into an infinitely dense point. This would mean that singularities, like the one in the Big Bang theory, are a natural and inevitable part of the universe. However, some scientists now think that the rules of quantum physics mean you can't keep squishing matter together forever. According to quantum physics, you can't pin down a quantum particle to a single point and two particles can't occupy the exact same location. This means that black holes must stop collapsing before gravity squishes matter into a single infinitely dense point. Professor Gaztanaga told MailOnline: 'Infinities may appear in mathematics, but they have no physical meaning. Nature doesn't work with infinite masses or infinite precision.' Therefore, when a cloud of matter like the universe collapses under gravity it will squeeze on itself until it forms a black hole before hitting this limit and bouncing back. What forms out of that bounce is a universe which looks remarkably like our own, suggesting this could be a possible way our universe began. Professor Gaztanaga says this Black Hole Universe Theory is better than the Big Bang because it solves some 'major questions the Big Bang model leaves unanswered'. Most importantly, this theory gives a natural explanation for the two phases of the universe's expansion: the rapid phase of cosmic expansion and the later acceleration we are now observing. According to the researchers' mathematical solutions, both of these phases emerge from the physics of the bounce itself rather than from other factors like dark energy. Professor Gaztanaga says: 'Inflation is simply part of the same dynamical process - the collapse and bounce - so it doesn't need to be added as a separate mechanism.' However, this theory has some fairly wild consequences for our understanding of the universe as a whole. According to the Black Hole Universe, the entire observable universe is inside a black hole nested inside a large parent universe which could, itself, be inside another black hole. Professor Gaztanaga says: 'We don't know for sure, but the theory allows for black holes within black holes - a nested, possibly endless structure. 'The key insight is that our universe may not be the beginning of everything. We are not unique, just part of a larger system. 'It's a continuation of the Copernican principle: Earth is not the centre of the cosmos, our galaxy is not the only one, and our universe may not be either.' Critically, the Black Hole Universe theory makes predictions about the shape of the universe that we should soon be able to test. The researchers say that the 'smoking gun' would be that the structure of the universe should be ever so slightly curved. That would mean the angles in a giant cosmic triangle would add up to slightly less than the 180 degrees that they would make on a flat surface. Soon, with space telescopes such as Euclid or the European Space Agency's upcoming Arrakhis mission scientists will be able to see whether this is true, potentially re-writing our understanding of the universe. The Big Bang Theory is a cosmological model, a theory used to describe the beginning and the evolution of our universe. It says that the universe was in a very hot and dense state before it started to expand 13,7 billion years ago. This theory is based on fundamental observations. In 1920, Hubble observed that the distance between galaxies was increasing everywhere in the universe. This means that galaxies had to be closer to each other in the past. In 1964, Wilson and Penzias discovered the cosmic background radiation, which is a like a fossil of radiation emitted during the beginning of the universe, when it was hot and dense. The cosmic background radiation is observable everywhere in the universe. The composition of the universe - that is, the the number of atoms of different elements - is consistent with the Big Bang Theory. So far, this theory is the only one that can explain why we observe an abundance of primordial elements in the universe.
IOL News
6 days ago
- General
- IOL News
What if the Big Bang wasn't the beginning? It may have taken place inside a black hole
The Big Bang is often described as the explosive birth of the universe. But what if this was not the beginning at all? Image: Vadim Sadovski/Shutterstock Enrique Gaztanaga The Big Bang is often described as the explosive birth of the universe – a singular moment when space, time and matter sprang into existence. But what if this was not the beginning at all? What if our universe emerged from something else – something more familiar and radical at the same time? In a new paper, published in Physical Review D, my colleagues and I propose a striking alternative. Our calculations suggest the Big Bang was not the start of everything, but rather the outcome of a gravitational crunch or collapse that formed a very massive black hole – followed by a bounce inside it. This idea, which we call the black hole universe, offers a radically different view of cosmic origins, yet it is grounded entirely in known physics and observations. Today's standard cosmological model, based on the Big Bang and cosmic inflation (the idea that the early universe rapidly blew up in size), has been remarkably successful in explaining the structure and evolution of the universe. But it comes at a price: it leaves some of the most fundamental questions unanswered. For one, the Big Bang model begins with a singularity – a point of infinite density where the laws of physics break down. This is not just a technical glitch; it's a deep theoretical problem that suggests we don't really understand the beginning at all. To explain the universe's large-scale structure, physicists introduced a brief phase of rapid expansion into the early universe called cosmic inflation, powered by an unknown field with strange properties. Later, to explain the accelerating expansion observed today, they added another 'mysterious' component: dark energy. In short, the standard model of cosmology works well – but only by introducing new ingredients we have never observed directly. Meanwhile, the most basic questions remain open: where did everything come from? Why did it begin this way? And why is the universe so flat, smooth, and large? New model Our new model tackles these questions from a different angle – by looking inward instead of outward. Instead of starting with an expanding universe and trying to trace back how it began, we consider what happens when an overly dense collection of matter collapses under gravity. This is a familiar process: stars collapse into black holes, which are among the most well-understood objects in physics. But what happens inside a black hole, beyond the event horizon from which nothing can escape, remains a mystery. In 1965, the British physicist Roger Penrose proved that under very general conditions, gravitational collapse must lead to a singularity. This result, extended by the late British physicist Stephen Hawking and others, underpins the idea that singularities – like the one at the Big Bang – are unavoidable. The idea helped win Penrose a share of the 2020 Nobel prize in physics and inspired Hawking's global bestseller A Brief History of Time: From the Big Bang to Black Holes. But there's a caveat. These 'singularity theorems' rely on 'classical physics' which describes ordinary macroscopic objects. If we include the effects of quantum mechanics, which rules the tiny microcosmos of atoms and particles, as we must at extreme densities, the story may change. In our new paper, we show that gravitational collapse does not have to end in a singularity. We find an exact analytical solution – a mathematical result with no approximations. Our maths show that as we approach the potential singularity, the size of the universe changes as a (hyperbolic) function of cosmic time. This simple mathematical solution describes how a collapsing cloud of matter can reach a high-density state and then bounce, rebounding outward into a new expanding phase. But how come Penrose's theorems forbid out such outcomes? It's all down to a rule called the quantum exclusion principle, which states that no two identical particles known as fermions can occupy the same quantum state (such as angular momentum, or 'spin'). And we show that this rule prevents the particles in the collapsing matter from being squeezed indefinitely. As a result, the collapse halts and reverses. The bounce is not only possible – it's inevitable under the right conditions. Crucially, this bounce occurs entirely within the framework of general relativity, which applies on large scales such as stars and galaxies, combined with the basic principles of quantum mechanics – no exotic fields, extra dimensions or speculative physics required. What emerges on the other side of the bounce is a universe remarkably like our own. Even more surprisingly, the rebound naturally produces the two separate phases of accelerated expansion – inflation and dark energy – driven not by a hypothetical fields but by the physics of the bounce itself. The SpaceX Falcon 9 rocket carrying ESA's Euclid mission on the launch pad in 2023. Image: ESA Testable predictions One of the strengths of this model is that it makes testable predictions. It predicts a small but non-zero amount of positive spatial curvature – meaning the universe is not exactly flat, but slightly curved, like the surface of the Earth. This is simply a relic of the initial small over-density that triggered the collapse. If future observations, such as the ongoing Euclid mission, confirm a small positive curvature, it would be a strong hint that our universe did indeed emerge from such a bounce. It also makes predictions about the current universe's rate of expansion, something that has already been verified. This model does more than fix technical problems with standard cosmology. It could also shed new light on other deep mysteries in our understanding of the early universe – such as the origin of supermassive black holes, the nature of dark matter, or the hierarchical formation and evolution of galaxies. These questions will be explored by future space missions such as Arrakhis, which will study diffuse features such as stellar halos (a spherical structure of stars and globular clusters surrounding galaxies) and satellite galaxies (smaller galaxies that orbit larger ones) that are difficult to detect with traditional telescopes from Earth and will help us understand dark matter and galaxy evolution. These phenomena might also be linked to relic compact objects – such as black holes – that formed during the collapsing phase and survived the bounce. The black hole universe also offers a new perspective on our place in the cosmos. In this framework, our entire observable universe lies inside the interior of a black hole formed in some larger 'parent' universe. We are not special, no more than Earth was in the geocentric worldview that led Galileo (the astronomer who suggested the Earth revolves around the Sun in the 16th and 17th centuries) to be placed under house arrest. We are not witnessing the birth of everything from nothing, but rather the continuation of a cosmic cycle – one shaped by gravity, quantum mechanics, and the deep interconnections between them. | The Conversation Enrique Gaztanaga is Professor at Institute of Cosmology and Gravitation (University of Portsmouth), University of Portsmouth
