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Dark Matter

I've recently read a report that they are conjectured to have two up, two down, and two strange. up have +2/3, down and strange have -1/3 charge, so they would be electrically neutral, and doubly-strange (literally).

I'll have to look that up.Thanks.
 
A long-lost type of dark matter may resolve the biggest disagreement in physics

Source: livescience.com
Date: 29 April, 2020

One of the deepest mysteries in physics, known as the Hubble tension, could be explained by a long-since vanished form of dark matter.

The Hubble tension, as Live Science has previously reported, refers to a growing contradiction in physics: The universe is expanding, but different measurements produce different results for precisely how fast that is happening. Physicists explain the expansion rate with a number, known as the Hubble constant (H0). H0 describes an engine of sorts that’s driving things apart over vast distances across the universe. According to Hubble’s Law (where the constant originated), the farther away something is from us, the faster it's moving.

And there are two main ways of calculating H0. You can study the stars and galaxies we can see, and directly measure how fast they're moving away. Or you can study the cosmic microwave background (CMB), an afterglow of the Big Bang that fills the entire universe, and encodes key information about its expansion.

As the tools for performing each of these measurements have gotten more precise, however, it's become clear that CMB measurement and direct measurements of our local universe produce incompatible answers.

Researchers have offered different explanations for the disparity, from problems with the measurements themselves to the possibility we live in a low-density "bubble" within the larger universe. Now, a team of physicists is suggesting that the universe might have fundamentally changed between the time after the Big Bang and today. If an ancient form of dark matter decayed out of existence, that loss would have changed the mass of the universe; and with less mass, there would be less gravity holding the universe together, which would have impact the speed at which the universe expands — leading to the contradiction between the CMB and the direct measurements of the universe's expansion rate.

https://www.livescience.com/amp/lost-dark-matter-hubble-tension.html
 
Simulation Reveals What Dark Matter Might Look Like if We Could See It

Source: sciencealert.com
Date: 7 September, 2020

How do you study something invisible? This is a challenge that faces astronomers who study dark matter.

Although dark matter comprises 85 percent of all matter in the Universe, it doesn't interact with light. It can only be seen through the gravitational influence it has on light and other matter. To make matters worse, efforts to directly detect dark matter on Earth have been unsuccessful so far.

Despite the elusive quality of dark matter, we have learned several things about it.

We know that it is not just dark but cold. As a result, it clumps together, forming the seeds of galaxy clusters. It also often forms halos around galaxies, making up the majority of a galaxy's mass.

However, there are still many unanswered questions about dark matter, so astronomers often develop new models for dark matter, comparing them to observation to test their accuracy.

One way this is done is through sophisticated computer simulations.

Recently a team from the Harvard & Smithsonian Center for Astrophysics ran a detailed simulation of the dark matter cosmos, and it has produced some surprising results.

[...]

https://www.sciencealert.com/simulation-reveals-what-dark-matter-might-look-like-if-we-could-see-it
 
Physicists May Have The First Experimental Evidence of a New Type of Dark Boson

Dark bosons are dark matter candidates based on force-carrying particles that don't really pack much force.

Unlike the bosons we're more familiar with, such as the photons that bind molecules and the gluons that hold atomic nuclei together, an exchange of dark bosons would barely affect their immediate surroundings.

If they existed, on the other hand, their collective energy could be responsible for making up dark matter - the missing mass that provides the extra gravity needed to keep our Universe of stars in their familiar formations.

Unfortunately, the presence of such bosons would be about as detectable as a murmur in a storm. For a physicist, however, a murmur might be enough to still be noticeable given the right kind of experiment.

It would seem to be theoretical - 2 experiments were carried out, one by MIT, the other Aarhus University. One found something odd, the other didn't. If you can understand the details you're doing better than me.
 
A new dark matter map appears to show its distribution throughout the universe.

"An international team of researchers has created the largest and most detailed map of the distribution of so-called dark matter in the Universe.

The results are a surprise because they show that it is slightly smoother and more spread out than the current best theories predict.

The observation appears to stray from Einstein's theory of general relativity - posing a conundrum for researchers.
The results have been published by the Dark Energy Survey Collaboration.

Dark Matter is an invisible substance that permeates space. It accounts for 80% of the matter in the Universe."

https://www.bbc.com/news/science-environment-57244708
 
Just turn the lights off in your lounge at night. I did and my shin discovered some 'dark matter' within seconds.

Worldwide coordinated search for dark matter
An international team of researchers (...) has published for the first time comprehensive data on the search for dark matter using a worldwide network of optical magnetometers.
https://phys.org/news/2022-01-worldwide-dark.html
 
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