Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: cosmology

The Universe Is Accelerating…and No One Knows Why

Support the Research Behind this Channel on Patreon:
/ arvinash.

REFERENCES
How black holes may be responsible for Dark Energy • How BLACK HOLES May be Responsible for DAR…
Is Dark Energy made of particles? • Is Dark ENERGY made of PARTICLES? The Quin…
What is Dark Energy made of? • What is Dark Energy made of? Quintessence?… CHAPTERS 0:00 The 70% mystery 0:58 How Dark Energy was discovered? 4:26 What could be causing Dark Energy? 6:58 Repulsive Gravity? 10:16 What is the energy made of? 11:56 Evolving Dark energy? Quintesssence 14:18 Could Dark Energy be a particle? 16:43 Could Black Holes cause Dark Energy? SUMMARY Dark energy is one of the greatest mysteries in modern physics. It appears to make up nearly 70% of the universe, yet scientists still do not know what it is. Unlike matter, it does not clump together. Unlike radiation, it does not dilute as space expands. Instead, it causes the expansion of the universe to accelerate, pushing galaxies apart faster over time. The discovery of this acceleration came in the late 1990s when astronomers measured distant Type Ia supernovae, which act as reliable “standard candles.” By comparing their brightness and redshift, researchers could determine how fast the universe expanded at different points in cosmic history. Instead of finding that gravity slowed expansion—as expected—they discovered the opposite: the universe was expanding faster and faster. This unexpected result led to the concept of dark energy, the unknown driver behind cosmic acceleration. One possible explanation is that dark energy is a cosmological constant, represented by the Greek letter lambda in Einstein’s equations. In this model, empty space itself contains a constant energy density known as vacuum energy. Quantum mechanics predicts that empty space is not truly empty; quantum fields constantly fluctuate, producing short-lived “virtual particles.” These fluctuations create energy even in a vacuum. Experiments like the Casimir effect provide evidence that vacuum energy is real. However, this explanation has a major problem. When physicists calculate vacuum energy using quantum theory, the predicted value is about 10¹²⁰ times larger than what observations of the universe allow. This enormous mismatch is widely considered the worst prediction in physics. In general relativity, cosmic acceleration can occur if the universe contains energy with negative pressure. In the Friedmann equation, expansion accelerates when pressure is sufficiently negative relative to energy density. Dark energy appears to have exactly this property, effectively producing a form of repulsive gravity that stretches spacetime. Another possibility is that dark energy is not constant but comes from a dynamic field known as quintessence. In quantum theory, fields can have particle-like excitations, meaning dark energy might correspond to extremely weakly interacting particles. If the strength of this field changes over time, the acceleration of the universe could grow stronger. In extreme scenarios, this could eventually lead to a catastrophic future known as the Big Rip, where galaxies, stars, atoms, and even spacetime itself are torn apart. A more speculative idea suggests a connection between supermassive black holes and dark energy. Some recent studies have observed that black holes appear to grow more massive over billions of years than expected from normal matter accretion alone. Researchers have proposed that black holes might somehow be linked to dark energy, though current evidence only shows a correlation and not a confirmed causal explanation. #darkenergy For now, dark energy remains an observed phenomenon with multiple possible explanations. Whether it is a property of empty space, a new field of physics, or something even deeper, it stands as one of the most profound open questions in cosmology.

CHAPTERS
0:00 The 70% mystery
0:58 How Dark Energy was discovered?
4:26 What could be causing Dark Energy?
6:58 Repulsive Gravity?
10:16 What is the energy made of?
11:56 Evolving Dark energy? Quintesssence
14:18 Could Dark Energy be a particle?
16:43 Could Black Holes cause Dark Energy?

SUMMARY
Dark energy is one of the greatest mysteries in modern physics. It appears to make up nearly 70% of the universe, yet scientists still do not know what it is. Unlike matter, it does not clump together. Unlike radiation, it does not dilute as space expands. Instead, it causes the expansion of the universe to accelerate, pushing galaxies apart faster over time.

The discovery of this acceleration came in the late 1990s when astronomers measured distant Type Ia supernovae, which act as reliable “standard candles.” By comparing their brightness and redshift, researchers could determine how fast the universe expanded at different points in cosmic history. Instead of finding that gravity slowed expansion—as expected—they discovered the opposite: the universe was expanding faster and faster. This unexpected result led to the concept of dark energy, the unknown driver behind cosmic acceleration.

One possible explanation is that dark energy is a cosmological constant, represented by the Greek letter lambda in Einstein’s equations. In this model, empty space itself contains a constant energy density known as vacuum energy. Quantum mechanics predicts that empty space is not truly empty; quantum fields constantly fluctuate, producing short-lived “virtual particles.” These fluctuations create energy even in a vacuum. Experiments like the Casimir effect provide evidence that vacuum energy is real.

Continue reading “The Universe Is Accelerating…and No One Knows Why” | >

Do decoherence, gravity, dark matter and dark energy all originate from quantum corrections?

Only about 5% of the universe is composed of normal matter that we can directly observe, while the remaining 95% is widely believed to consist of dark matter and dark energy. Paradoxically, however, the nature of these dark components remains unknown. Is this due to limitations in our observational capabilities, or does it reflect a more fundamental incompleteness in the classical laws of physics that have long underpinned our understanding of the universe?

In a recent study published in the International Journal of Modern Physics D, I proposed that dark matter and dark energy may not correspond to physically existing substances, but could instead emerge as effective phenomena arising from the quantum nature of gravity.

The Universe Is Expanding Too Fast and Scientists Can’t Explain Why

The most precise measurement yet shows the Universe is expanding faster than expected, deepening the Hubble tension. The result hints that something may be missing from our current understanding of the cosmos.

An international team of astronomers has produced one of the most accurate measurements so far of how quickly the nearby Universe is expanding. Rather than settling a long-standing debate, the new result intensifies one of the biggest unresolved problems in cosmology. The collaboration includes John Blakeslee of NSF NOIRLab, which is funded by the U.S. National Science Foundation, and draws on data from telescopes across two NSF NOIRLab Programs.

Two competing ways to measure cosmic expansion.

CHIME tracks a hyperactive repeating fast radio burst source

Using the Canadian Hydrogen Intensity Mapping Experiment (CHIME), an international team of astronomers has performed radio observations of FRB 20220912A—a highly active source of repeating fast radio bursts. Results of the monitoring campaign, published April 10 on the preprint server arXiv, could help us better understand the nature of these enigmatic sources.

Fast radio bursts (FRBs) are intense bursts of radio emission lasting milliseconds showcasing the characteristic dispersion sweep of radio pulsars. The physical nature of these bursts is yet unknown, and astronomers consider a variety of explanations ranging from synchrotron maser emission from young magnetars in supernova remnants to cosmic string cusps.

Our Universe Might Be a Giant Brain, According to New Theories

There’s something quietly unsettling about placing a photograph of a human neuron next to a simulated image of the large-scale cosmic web. The two look almost identical: delicate, branching filaments connecting dense clusters, with vast open spaces in between. One fits inside your skull. The other stretches across billions of light-years. The resemblance is hard to dismiss, and for a growing number of researchers, it’s far more than a visual coincidence.

What started as a striking observation in cosmology and neuroscience has evolved into a serious theoretical question. Could the universe, at its most fundamental level, operate the way a brain does? The ideas being put forward aren’t purely philosophical. Some of them come with testable mathematics, published peer-reviewed papers, and the names of well-regarded physicists attached. What follows is an honest look at where the science currently stands.

The estimated 200 billion detectable galaxies aren’t distributed randomly, but are lumped together by gravity into clusters that form even larger clusters, which are connected to one another by “galactic filaments,” long thin threads of galaxies. This vast architecture is what scientists call the cosmic web. When you zoom far enough out, the structure of the entire observable universe begins to take on a shape that looks startlingly familiar.

Monster black holes are silencing star formation across the universe

Giant black holes may be secretly controlling how entire clusters of galaxies grow. A blazing supermassive black hole can influence far more than its own galaxy. Scientists found that quasars emit radiation strong enough to shut down star formation in nearby galaxies millions of light-years away. This could explain why some galaxies near early quasars appear faint or missing. The finding suggests galaxies grow and evolve together, not in isolation.

Powerful radiation from active supermassive black holes, which are believed to sit at the center of most galaxies, can do more than shape their own surroundings. A new study led by Yongda Zhu at the University of Arizona suggests these black holes can also slow the formation of stars in galaxies located millions of light-years away.

“Traditionally, people have thought that because galaxies are so far apart, they evolve largely on their own,” said Zhu, the study’s lead author, whose findings were published in The Astrophysical Journal Letters. “But we found that a very active, supermassive black hole in one galaxy can affect other galaxies across millions of light-years, suggesting that galaxy evolution may be more of a group effort.”

Does the Universe SPIN once every 500 billion years?!

AD | Up to 30% off on the Hoverpen Traverse on Kickstarter : https://www.kickstarter.com/projects/.… code DRBECKY to receive 10% off all Hoverpens and free shipping to most countries.
North America / UK / Australia / International: https://bit.ly/drbecky_noviumeu
EU: https://bit.ly/drbecky_noviumeu
Does the Universe spin? Think about it, planets spin, the Sun spins, galaxies spin, even black holes spin — so what about the entire Universe? And if it was spinning could this help solve one of the biggest problems in astrophysics today — the \.

/* */