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Archive for the ‘cosmology’ category: Page 51

May 21, 2024

NA64 uses the high-energy SPS muon beam to search for dark matter

Posted by in categories: cosmology, particle physics

The NA64 experiment started operations at CERN’s SPS North Area in 2016. Its aim is to search for unknown particles from a hypothetical “dark sector.” For these searches, NA64 directs an electron beam onto a fixed target. Researchers then look for unknown dark sector particles produced by collisions between the beam’s electrons and the target’s atomic nuclei.

May 20, 2024

If we consider the spacetime of the universe to be four-dimensional, does the Big Bang lie in its center?

Posted by in categories: cosmology, physics

Apologies for the (hopefully now somewhat less) clickbait-y title. Now, of course, I know that the Big Bang did not happen at any point connected to a single point in our current $3$-dimensional observable universe by a one-dimensional causal curve. I also know that at any point in the universe, all other points seem to be moving away from that point. However, according to our current understanding of physics, the universe is (at least) $4$-dimensional. Just like how in the classical “balloon” analogy for an expanding universe, the points do in fact all move away from a common point on the interior of the balloon, all spacetime points do move away from the Big Bang, or at least some kind of cosmological horizon which surrounds it — this is how I understand going forward in time, at least. Does it make sense to think of this as a sort of “center” for the full, $4$-dimensional spacetime? Or are there further subtleties to this situation?

May 19, 2024

Black hole singularities defy physics. New research could finally do away with them

Posted by in categories: cosmology, physics

Black hole singularities defy the laws of physics. New research presents a bold solution to this puzzle: Black holes may actually be a theoretical type of star called a ‘gravastar,’ filled with universe-expanding dark energy.

May 19, 2024

Why a giant ‘cold spot’ in the cosmic microwave background has long perplexed astronomers

Posted by in category: cosmology

Leftover light from the young universe has a major flaw, and we don’t know how to fix it. It’s the cold spot. It’s just way too big and way too cold. Astronomers aren’t sure what it is, but they mostly agree that it’s worth investigating.

The cosmic microwave background (CMB) was generated when our universe was only 380,000 years old. At the time, our cosmos was about a million times smaller than it is today and had a temperature of over 10,000 kelvins (17,500 degrees Fahrenheit, or 9,700 degrees Celsius), meaning all of the gas was plasma. As the universe expanded, it cooled, and the plasma became neutral. In the process, it released a flood of white-hot light. Over the billions of years since, that light has cooled and stretched to a temperature of around 3 kelvins (minus 454 F, or minus 270 C), putting that radiation firmly in the microwave band of the electromagnetic spectrum.

May 19, 2024

Evolutionary Emergence: From Primordial Atoms to Living Algorithms of Artificial Superintelligence

Posted by in categories: biological, cosmology, information science, particle physics, quantum physics, robotics/AI

To be clear, humans are not the pinnacle of evolution. We are confronted with difficult choices and cannot sustain our current trajectory. No rational person can expect the human population to continue its parabolic growth of the last 200 years, along with an ever-increasing rate of natural resource extraction. This is socio-economically unsustainable. While space colonization might offer temporary relief, it won’t resolve the underlying issues. If we are to preserve our blue planet and ensure the survival and flourishing of our human-machine civilization, humans must merge with synthetic intelligence, transcend our biological limitations, and eventually evolve into superintelligent beings, independent of material substrates—advanced informational beings, or ‘infomorphs.’ In time, we will shed the human condition and upload humanity into a meticulously engineered inner cosmos of our own creation.

Much like the origin of the Universe, the nature of consciousness may appear to be a philosophical enigma that remains perpetually elusive within the current scientific paradigm. However, I emphasize the term “current.” These issues are not beyond the reach of alternative investigative methods, ones that the next scientific paradigm will inevitably incorporate with the arrival of Artificial Superintelligence.

The era of traditional, human-centric theoretical modeling and problem-solving—developing hypotheses, uncovering principles, and validating them through deduction, logic, and repeatable experimentation—may be nearing the end. A confluence of factors—Big Data, algorithms, and computational resources—are steering us towards a new type of discovery, one that transcends the limitations of human-like logic and decision-making— the one driven solely by AI superintelligence, nestled in quantum neo-empiricism and a fluidity of solutions. These novel scientific methodologies may encompass, but are not limited to, computing supercomplex abstractions, creating simulated realities, and manipulating matter-energy and the space-time continuum itself.

May 18, 2024

What If the Universe had No Beginning?

Posted by in categories: cosmology, quantum physics

In this episode, we’ve embarked on an exciting journey into the heart of quantum cosmology, exploring Stephen Hawking’s revolutionary \.

May 16, 2024

The chorus of gravitational waves ripple throughout the universe has finally been ‘heard’ by scientists

Posted by in categories: cosmology, physics

For the first time, scientists have seen the small ripples that result from black holes’ motion, which are gently stretching and squeezing everything in the universe.

They revealed that they could “hear” low-frequency gravitational waves, which are produced by massive objects colliding and moving around in space and causing changes in the universe’s fabric.

May 16, 2024

Is Dark Energy Evolving?

Posted by in categories: cosmology, futurism

Life is shaped by choices. The fundamental debate is whether to live life for learning or for pleasure. This weekend, my existential tension boiled down to a simple question: why am I writing my next book and my next scientific paper rather than having fun in the sun?

After some contemplation, I came up with the realization that learning is pleasure. But there is another benefit to writing. Most people will live in the future and I wish to communicate my thoughts to those who will be born long after I am gone. I weigh my priorities in life based on the number of people who might benefit from my actions.

There are currently 8.1 billion people on Earth, about 7% of the total number of humans who have ever lived since the Big Bang, 117 billion. Based on the star count from the Gaia sky survey, the number of stars in the Milky-Way galaxy is comparable to this total value within a factor of a few. This implies that for the foreseeable future, Milky-Way stars could be named after each person who ever lived on Earth.

May 16, 2024

The hubble tension

Posted by in category: cosmology

The first anomaly concerns the speed at which the Universe is expanding. Astronomers determine this in two ways and herein lies the problem: the two methods yield different values.

The obvious method is to observe galaxies (the basic building blocks of the Universe) in the nearby Universe and measure how fast they’re moving away from us. They’re scattering like pieces of cosmic shrapnel in the aftermath of the Big Bang, the titanic explosion in which the Universe was born 13.82 billion years ago.

May 16, 2024

Using a Floquet quantum detector to constrain axion-like dark matter

Posted by in categories: cosmology, particle physics, quantum physics

A team of researchers affiliated with several institutions in Israel has used a Floquet quantum detector to constrain axion-like dark matter, hoping to reduce its parameter space. In their paper published in the journal Science Advances, the group describes their approach to constraining the theoretical dark matter particle as a means to learning more about its properties.

Despite several years of effort by physicists around the world, remains a mystery. Most physicists agree that it exists, but thus far, no one has been able to prove it. One promising theory involving the existence of interacting has begun to lose its luster, and some teams are looking for something else. In this new effort, the researchers seek axions, or axion-like particles. Such dark matter particles have been theorized to be zero-spin and able to possess any number of combinations of mass and interaction strength. The team sought to constrain the features of axion-like particles to reduce the number of possibilities of their existence and thereby increase the chances of proving their existence.

The researchers used a shielded glass cell filled with rubidium-85 and xenon-129 atoms. They fired two lasers at the cell—one to polarize the rubidium atoms’ electronic spin and the xenon’s nuclear spin, and the other to measure spin changes. The experiment was based on the idea that the oscillating field of the axions would impact on the xenon’s spin when they are close in proximity. The researchers then applied a to the cell as a means of blocking the spin of the xenon to within a narrow range of frequencies, allowing them to scan the possible oscillation frequencies that correspond to the range of the axion-like particles. Under this scenario, the Floquet field is theorized to have a frequency roughly equal to the difference between the (NMR) and the electron paramagnetic resonance, and their experiment closes that gap.

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