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The Search for Dark Matter Continues, More Than a Mile Underground
Popular Mechanics ^ | May 9, 2018 | Jay Bennett

Posted on 05/10/2018 7:40:41 AM PDT by C19fan

For decades, astrophysicists have pondered the odd movements of galaxies across the cosmos. The visible matter of the universe appears to be tugged around by an invisible counterpart, material that does not interact with surrounding matter in any observable way save gravity: dark matter. Refined measurements have since led scientists to hypothesize that 85 percent of all the matter in the universe is dark matter, while only 15 percent accounts for you, me, the planet, the stars, and everything else we can see.

It's a satisfactory explanation for our observations that has one major problem: a dark matter particle has never been detected directly. But the search for elusive dark matter is about to get a shot in the arm, and rather than looking for evidence of the substance written in the stars, scientists are constructing ambitious experiments deep underground.

The SLAC National Accelerator Laboratory, partnered with Stanford University and multiple additional labs and universities around the world, just announced that the U.S. Department of Energy has approved funding and construction a of dark matter experiment 6,800 feet underground in an old nickel mine. The project, called the SuperCDMS SNOLAB experiment, will use supercooled silicon and germanium crystals in an attempt to detect dark matter particles as they pass through our planet. The experiment is expected to be 50 times more sensitive than previous efforts, and it is slated to come online in the early 2020s.

(Excerpt) Read more at popularmechanics.com ...


TOPICS: Astronomy; Science
KEYWORDS: gravity; matter; stringtheory
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To: rjsimmon

I recommend “the 4% Universe” by Panek.

As for what it is, I am still putting my $.02 on unobserved dust and gravel.

But, the gravitation abnormalities caused by black holes and other deep gravity wells may still be part.


41 posted on 05/10/2018 12:06:50 PM PDT by Conan the Librarian (The Best in Life is to crush my enemies, see them driven before me, and the Dewey Decimal System)
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To: Justa

Though the matter that we do see is likewise comprised of sub-atomic particles. How could such a medium that couples to gravitation, an is said to be so pervasive that it dominates the structures of galaxies, not occasionally coalesce into a clump, forming larger clumps? We are told that its total mass within the universe exceeds ordinary matter, yet we see and feel the effects of the lesser but not the greater.

I feel we need a better theory. But damned if I know what it should contain.


42 posted on 05/10/2018 12:16:04 PM PDT by onedoug
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To: rjsimmon

This is the latest example of physicists saying “trust us, we’re smarter than you” without any evidence to back up their claims.

...

I wonder why they would bother with this experiment that is fifty times more sensitive if what you’re saying is true.


43 posted on 05/10/2018 12:17:57 PM PDT by Moonman62 (Give a man a fish and he'll be a Democrat. Teach a man to fish and he'll be a responsible citizen.)
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To: onedoug

Though the matter that we do see is likewise comprised of sub-atomic particles. How could such a medium that couples to gravitation, an is said to be so pervasive that it dominates the structures of galaxies, not occasionally coalesce into a clump, forming larger clumps?

...

By its very nature dark matter can’t form dense clumps like matter that “feels” the other forces.

When you’re standing, there is more ordinary matter below your feet than above, so the scale goes bonkers when you stand on it.

With dark matter there is just as much mass above as there is below, so you don’t feel it and it has no effect on your poor scale.

What we need is more precise observations, so we can determine what makes up dark matter.


44 posted on 05/10/2018 12:28:49 PM PDT by Moonman62 (Give a man a fish and he'll be a Democrat. Teach a man to fish and he'll be a responsible citizen.)
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To: PLMerite

Just rock down there. Though the presence of bacteria in the deepest well samples sets me to wondering if biology extends into the mantle. Though I suspect life pretty much ceases near the Moho. Pretty frickin’ hot therein.


45 posted on 05/10/2018 12:29:37 PM PDT by onedoug
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To: thoughtomator

I’ll leave you to your weird metaphors and overheated rhetoric. My knowledge is in the scientific area.


46 posted on 05/10/2018 12:43:02 PM PDT by Steely Tom ([Seth Rich] == [the Democrat's John Dean])
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To: Steely Tom

Simple version - one of the following is more likely to be true:

a) the theory of gravity, as we know it, is wrong

b) the universe is almost entirely composed of stuff that exists only to make the theory of gravity compatible with our observations

Why would any sane person pick (b)?


47 posted on 05/10/2018 1:36:01 PM PDT by thoughtomator (Number of arrested coup conspirators to date: 0)
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To: thoughtomator
OK, so how is the theory of gravity "wrong" ?

What is your fix?

48 posted on 05/10/2018 1:39:44 PM PDT by Steely Tom ([Seth Rich] == [the Democrat's John Dean])
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To: Steely Tom

How, is a question I can’t answer. But people should be looking into it instead of spending money on dark matter boondoggles.

By how much, ironically, I can answer. Our theory of gravity is approximately 96% wrong, if estimates of dark stuff are correct. That’s how much of the universe they needed to invent out of thin air to make this theory of gravity work.

If the idea of “dark matter” has any use at all, it’s to establish precisely how wrong our theory of gravity is.

Clearly there’s more to it than “there should be stuff here, but there’s no stuff, but let’s assume there’s stuff anyway because we have to to make the theory work”.


49 posted on 05/10/2018 2:10:16 PM PDT by thoughtomator (Number of arrested coup conspirators to date: 0)
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To: thoughtomator
How, is a question I can’t answer.

You can't say how it's wrong, but you know something called "dark matter" can't be part of the solution.

The subatomic particle called the neutrino was originally hypothesized by Wolfgang Pauli as a way to explain mysterious results that were seen when observing the distribution of beta particle (electron) velocities during radioactive decay.

Pauli knew that these "particles" would have strange characteristics and would be very hard to detect by direct observation, but that they were necessary under the known and widely accepted conservation laws for momentum and energy.

The first direct experimental evidence for the actual physical existence of neutrinos wasn't detected until 1956, twenty-six years after Pauli hypothesized their existence; their proof wasn't rewarded with a Nobel prize until 1995, almost fourty years later, 65 years after Pauli conjured up the neutrino as a conceptual entity that was necessary in order not to have to question basic conservation principles that were seen as underlying all of physics.

For long stretches of that 65 year time interval, from Pauli's first suggestion until the neutrino was accorded the gold standard of acceptance represented by the Nobel prize, it was seen as "dark matter" too, in a way. People looked and looked and looked for them. Another test that confirmed the physical existence of the neutrino was that of the Homestake Experiment of Davis and Bahcall, which detected the flux of neutrinos issuing from the sun; this experiment was the first to reveal an even stranger, weirder characteristic of neutrinos, which is that they change characteristics as they fly through space. Weird, strange, crazy... but — apparently — true. This phenomenon, called neutrino oscillation, won for its discoverers another Nobel Prize, in 2002.

At least four Nobel Prizes have been awarded for work on neutrinos; the latest was in 2015, 85 years after their existence was first proposed.

I don't know whether "dark matter" really exists, or whether that term is a stand-in, a metaphor, a conceptual model, for something more subtle than a particle or a field phenomenon. I don't think of it as anything like that. No one has seen it directly; it exists only as a construct supported only by inferential evidence.

But the story of the neutrino demonstrates that sometimes the most inferential evidence for a thing called 'X' can be borne out by later results, and eventually, after many years of experimental observation, 'X' is found to literally exist.

50 posted on 05/10/2018 2:59:20 PM PDT by Steely Tom ([Seth Rich] == [the Democrat's John Dean])
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To: DrainBamage

Kevmo? Is that you?


51 posted on 05/10/2018 4:51:28 PM PDT by samtheman (LetÂ’s elect as many Republicans as possible in 2018)
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To: onedoug

Consider the amount of energy released from splitting an atom. Wouldn’t a similar amount of energy be required to create an atom?

Dark matter may only form clumps in the presence of atomic or finite matter. Without sufficient energy to create an atom dark matter is incapable of interacting with anything by any known means. It can only accompany matter, it cannot interact with it. We can see its effects in such things as the rotational speed of galaxies which is way too fast for the estimated mass.

/Evening thoughts.


52 posted on 05/10/2018 5:05:06 PM PDT by Justa
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To: Steely Tom

I’m saying that if you were going to follow the exact opposite of what Occam’s Razor demands, then you would solve the problem of why gravity isn’t performing as expected by doing something like multiplying the amount of stuff in the universe by 20.

As a practice, it’s qualitatively different from predicting a minor particle’s existence as a necessary result of laws of energy conservation. The minor particle is the smallest part of the picture, it doesn’t require something as radical as completly altering the size and shape of the universe in order to fit the theory.

The scale and scope of the proposed alteration to our picture of reality is so vast, and grounded on so little, and the experiments so essentially flawed in their anti-scientific method property of non-reproducability, that pursuit of dark matter amounts to a religion at this point, and not science.


53 posted on 05/10/2018 5:10:33 PM PDT by thoughtomator (Number of arrested coup conspirators to date: 0)
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To: Justa
It can only accompany matter, it cannot interact with it. We can see its effects in such things as the rotational speed of galaxies which is way too fast for the estimated mass.

If I understand your latter point here, it's dark matter which keeps galaxies from flying apart, which they would given their measurable masses if not so corralled. So there must be interaction there, as both systems couple to gravity.

I rather suspect we're missing something in the overall masses. A black hole of ~one million solar masses is thought to reside at the cores of most galaxies. But who knows how many of these there actually are in any given galaxy? It could be millions, and even billons. That's an awful lot of mass otherwise unaccounted for.

Maybe I'm screwy. But the universe tends to be simple in nature...even if we can't figure it out all at the same time.

54 posted on 05/10/2018 5:52:45 PM PDT by onedoug
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To: Justa
Consider the amount of energy released from splitting an atom. Wouldn’t a similar amount of energy be required to create an atom?

I might review my textbooks a bit, but that goes to the relationships twixt fission and fusion reactions. It takes a lot more energy re the latter.

55 posted on 05/10/2018 6:01:47 PM PDT by onedoug
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To: thoughtomator
"The dark matter fraudpothesis demands that you accept the infallability of current theories of gravity."

It may be based on current theories of gravity, but nobody is demanding you accept the infallibility of anything. That's you making things up.

56 posted on 05/10/2018 9:56:59 PM PDT by mlo
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To: Safetgiver
"Take a full bucket of water and sling it around in a circle from your shoulder. The water don’t fall out. Same principle."

Centrifugal force does not reduce or change gravity. It's an additional force acting upon an object, related to the object's inertia.

57 posted on 05/10/2018 9:59:15 PM PDT by mlo
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To: mlo

I’m not making anything up. The entire purpose of the invention of dark matter is to patch the failure of the theory to match observation, and starts from the (IMO faith-based) premise that the theory must be correct.

Dark matter is literally the invention of new data to make the theory work. That all the key advances are now non-reproducable, tightly-controlled experiments with limited transparency only serve to reinforce its fraudulent nature.


58 posted on 05/11/2018 8:04:06 AM PDT by thoughtomator (Number of arrested coup conspirators to date: 0)
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To: Moonman62
I wonder why they would bother with this experiment that is fifty times more sensitive if what you’re saying is true.

Is it not obvious?

$$$$


59 posted on 05/11/2018 11:23:46 AM PDT by rjsimmon (The Tree of Liberty Thirsts)
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To: thoughtomator
"I’m not making anything up."

You are. You are making up the notion that someone is running around demanding you have "faith" in dark matter. Nobody is doing that. It's a theory. Nobody cares whether you or I believe it.

"The entire purpose of the invention of dark matter is to patch the failure of the theory to match observation,"

That's exactly how theories get developed. That's how science works. Theories are supposed to agree with observation, and incomplete theories may need to be modified to do so.

"...and starts from the (IMO faith-based) premise that the theory must be correct."

See above. But again, faith is not required to posit a theory, even by the people proposing it. They are ideas, subject to testing. Science evaluates different ideas. Not all of them work out in the end. That's how it's supposed to work. You fail to understand the scientific process.

60 posted on 05/12/2018 10:37:16 AM PDT by mlo
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