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Searching for Dark Matter

lpetrich

lpetrich

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Dark Matter is the name given to a mysterious substance that contributes much of the Universe's mass. Strictly speaking, it is not "dark" but invisible. The only evidence that we have of its existence is from its gravity -- we have yet to discover any convincing nongravitational evidence of its existence.

4 Dark Matter Experiments to Keep an Eye on in 2019
LIGO comes back online
Can LIGO Find the Missing Dark Matter?
It might be primordial black holes, and LIGO might detect g-wave evidence of them.

Physicists will try to figure out whether MiniBooNE gave up the ghost of a neutrino
Possible evidence of "sterile neutrinos" in its data.

First light at the Large Synoptic Survey Telescope (LSST)
There's a telescope being built in Chile that will make detailed images of vast regions of the sky every 15 seconds, completing a full scan of the sky every three days. Over the course of 10 years, it will compare those images to one another again and again to track how the sky shifts and changes, providing the most in-depth-ever resource for understanding how dark matter pushes and pulls on the cosmos.
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The race to build a next-generation detector will heat up
Particle physicists have speculated for a long time that the first direct sign of dark matter might be a sparkle. Here's how it might work: As dark matter collides with inert substances in very dark rooms, those substances would emit faint specks of light. For decades, scientists have built detectors according to this principle, but so far, none have produced a conclusive result.
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Not just sparkles of light, but "sparkles" of sound, from dark-matter particles bouncing off of detector-material atomic nuclei.

Three experiments are being worked on, each of which will look at 4 to 10 tons of xenon. They should start operation this year or the next.
 
So, is there really a Planck energy for a particle at which it basically will be its own black hole?

https://en.wikipedia.org/wiki/Planck_energy

So, even the Oh My God particle was somewhere on the order of 2.5×10−8 Planck Energy and this article says that the LHC is 10^-15 times as energetic per particle than the Planck Energy.

https://www.scientificamerican.com/article/quantum-black-holes-2007-04/

Could it be that Dark Matter and Baryonic Matter can only inter-convert at appreciable rates at say 10-4 Planck Energy?

This is just spitballing, of course.

But that may explain why Dark Matter is inert now.
 
Review of Direct Dark-Matter Searches

A new elementary particle? It would be a Weakly Interacting Massive Particle, a WIMP.

Supersymmetry neutralino? Gravitino? Axion? Sterile neutrino? Something else?

WIMP's would be relics of the early Universe, produced when the Universe was hot enough to do so. Temperature ~ energy ~ mass*c^2.

How to make them?
  • The LHC: protons -> WIMP's + a lot of other stuff
  • Indirect: WIMP + WIMP -> familiar particles
  • Direct: WIMP + nucleus -> WiMP + kicked nucleus

We are in our galaxy's dark-matter halo, and our orbit in our galaxy will make a dark-matter "wind". Our orbit around the Sun will make a modulation of that wind: 30 km/s out of 220 km/s.

Need to reduce background events. To avoid cosmic rays, one must go deep underground. One must also try to remove radioactive isotopes of materials in the detectors. The ultimate background will be neutrinos, but we are still some way off from observing those particles. But upcoming experiments are getting closer and closer.
 
For the modeling of the early universe, there was the point when neutrinos decoupled from matter and now those neutrinos are not detectable due to cosmological redshifting except maybe in insanely subtle ways that also are affected by other processes. There was a thread on this a couple months ago.

Is it possible that if dark matter is made of elementary particle(s) that these also decoupled early on and are similarly redshifted and nearly undetectable? Of course it is the tiny mass of the neutrinos that allowed the high level of redshifting.

But even all the relic neutrino mass is not much, could these dark matter elementary particles add up to the missing mass and not totally mangle the big bang model?

This looks interesting

https://arxiv.org/abs/1706.06801
 
Information in our brains or in computers or books involves matter and energy. It is inescapable. To record information o any kind requires expending energy to change a state of matter.

As I understand it dark matter si a placeholder. It was coined to bringing theory back in line with observation. It has properties that make the theory work.

It is possible there is phemomrna that have an affecton our realty that we are unable to detect with our instrumentation.

Somethig is affecting motion ino ur observable unverse.
 
Swammerdami said:
We've all heard of mass-energy equivalence. But what about mass-energy-information equivalence? And thus the mystery of dark matter is solved!?!?!? The extra mass is just the extra mass due to information.

There is no dark matter. Instead, information has mass, physicist says.

Wow.
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In Scientology it has been discovered that mental energy is simply a finer, higher-level physical energy.

The test of this is conclusive in that a thetan, mocking-up (creating) mental image pictures and thrusting them into the body, can increase the body mass. And, by casting them away again, can decrease the body mass. This test has actually been made and an increase of as much as thirty pounds (actually measured on scales) has been added to and subtracted from a body by creating mental energy.
- L. Ron Hubbard

 
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