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Archive for the ‘cosmology’ category: Page 23

Sep 23, 2024

Thermodynamics of frozen stars

Posted by in categories: cosmology, information science, quantum physics

New study suggests that black holes may not be the featureless, structureless entities that Einstein’s general theory of relativity predicts them to be.


The frozen star is a recent proposal for a nonsingular solution of Einstein’s equations that describes an ultracompact object which closely resembles a black hole from an external perspective. The frozen star is also meant to be an alternative, classical description of an earlier proposal, the highly quantum polymer model. Here, we show that the thermodynamic properties of frozen stars closely resemble those of black holes: frozen stars radiate thermally, with a temperature and an entropy that are perturbatively close to those of black holes of the same mass. Their entropy is calculated using the Euclidean-action method of Gibbons and Hawking. We then discuss their dynamical formation by estimating the probability for a collapsing shell of “normal’’ matter to transition, quantum mechanically, into a frozen star.

Sep 23, 2024

Scientists propose a new method to search for dark matter using LIGO

Posted by in categories: cosmology, physics

A new study published in Physical Review Letters (PRL) proposes using gravitational wave detectors like LIGO to search for scalar field dark matter.

Sep 22, 2024

Primordial Dark Energy: Solving Astronomy’s Biggest Mysteries

Posted by in category: cosmology

Discover how primordial dark energy could unravel astronomy’s greatest puzzles—from the Hubble tension to early galaxy formation—with FreeAstroScience.

Sep 22, 2024

A 150-Year Flight to a New Earth | Sci-Fi Documentary 4K | ReYOUniverse

Posted by in categories: cosmology, education, media & arts

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

Sep 22, 2024

Bubbling, frothing and sloshing: Long-Hypothesized Plasma Instabilities Finally Observed

Posted by in categories: cosmology, nuclear energy, particle physics

Results could aid understanding of how black holes produce vast intergalactic jets. Scientists have observed new details of how plasma interacts with magnetic fields, potentially providing insight into the formation of enormous plasma jets that stretch between the stars.

Whether between galaxies or within doughnut-shaped fusion devices known as tokamaks, the electrically charged fourth state of matter known as plasma regularly encounters powerful magnetic fields, changing shape and sloshing in space. Now, a new measurement technique using protons, subatomic particles that form the nuclei of atoms, has captured details of this sloshing for the first time, potentially providing insight into the formation of enormous plasma jets that stretch between the stars.

Scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) created detailed pictures of a magnetic field bending outward because of the pressure created by expanding plasma. As the plasma pushed on the magnetic field, bubbling and frothing known as magneto-Rayleigh Taylor instabilities arose at the boundaries, creating structures resembling columns and mushrooms.

Sep 22, 2024

Transcendence: Many seek a path to enlightenment through study and meditation, but what does science tell us about transcendence?

Posted by in categories: cosmology, media & arts, science

And could entire civilizations seek to leave this reality behind?

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Continue reading “Transcendence: Many seek a path to enlightenment through study and meditation, but what does science tell us about transcendence?” »

Sep 21, 2024

Entire Swarm of Black Holes Detected Moving Through The Milky Way

Posted by in category: cosmology

I find it weird that black holes would be moving throughout the galaxy because most are stationary.


A fluffy cluster of stars spilling across the sky may have a secret hidden in its heart: a swarm of over 100 stellar-mass black holes.

The star cluster in question is called Palomar 5. It’s a stellar stream that stretches out across 30,000 light-years, and is located around 80,000 light-years away.

Continue reading “Entire Swarm of Black Holes Detected Moving Through The Milky Way” »

Sep 21, 2024

Mysterious Signal Hints at The Smallest Black Hole Ever Detected

Posted by in category: cosmology

A star wiggling oddly around in space may be the signpost to one of the most sought-after objects in the galaxy.

Some 5,825 light-years from Earth, a red giant star has been spotted moving as though in a slow orbital dance with a binary companion. The problem? There’s absolutely no light coming from the place where the binary companion should be.

It gets more interesting. Based on the behavior of the red giant, astronomers led by Song Wang of the Chinese Academy of Sciences have determined that the mass of the invisible object is just 3.6 times the mass of the Sun. There’s only one thing it could be: a black hole, one with a petite size that’s smack bang in the middle of a mysterious void in the data known as the lower mass gap.

Sep 20, 2024

Roger Penrose: Time, Black Holes, and the Cosmos

Posted by in categories: cosmology, evolution

Nobel Laureate Roger Penrose joins Brian Greene to explore some of his most iconic insights into the nature of time, black holes, and cosmological evolution.

Moderator: Brian Greene.
Participant: Sir Roger Penrose.

Continue reading “Roger Penrose: Time, Black Holes, and the Cosmos” »

Sep 19, 2024

The Secrets Behind The World’s Most Powerful Electric Motor — The Koenigsegg ‘Dark Matter’

Posted by in category: cosmology

The Dark Matter is built with incredibly complex technology. “Raxial Thrust” is a new term coined to describe the way the Dark Matter engine works. “Raxial” is a portmanteau of “radial” and “axial”. Typically, electric motors use one or the other. Radial motors have the magnetic coils of the electric motor perpendicular to the axis of its rotation. Axial motors are built with flux parallel to the rotation. Both have advantages and disadvantages.

Radial are typically easier to build and maintain, but axial are smaller and can create more power by weight and volume. Koenigsegg has figured out a way to do both in one motor. Since they do not have to show us the inside of their Dark Matter, we don’t exactly understand how they’ve done this, but clearly, it is effective in generating power and torque. Despite this, the motor does not actually revolve at a very high rate. The website shows a max RPM of 8,500.

Koenigsegg makes use of its own battery packs. It doesn’t build the cells from the ground up, but it creates the system that actually delivers the power to the car. For the Gemera, it has created batteries that have dielectric oil (an insulator that will prevent unwanted electrical reactions) funneled directly into them as a cooling system. Most batteries on EVs now use airflow systems directly attached to the battery to cool them, but Koenigsegg has gone for a liquid approach instead. If it’s effective, it may become a more widespread approach to battery cooling technology.

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