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General discussion

Obvious what dark matter is

Aug 3, 2019 8:16AM PDT

Hi,
Dark matter is just matter. Consider the space between known matter. Consider the size of the Universe.

Now "remove" all the, what we call known matter (15%-25%?).

All the remaining space is filled with matter that is molecules in size more or less. Can't be detected can't be seen.

AL

Discussion is locked

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Ya, you betcha.
Aug 3, 2019 10:07AM PDT

Still potholes on my street, though.Happy
Have you visited sciencenews.org? Great site. You'll find similar minds there.

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Update.
Nov 8, 2019 3:25PM PST

Science News online is no longer a comment site. Too much trolling and hating for their mods. Can't blame 'em.
Good magazine, though.

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Matter
Aug 3, 2019 1:57PM PDT

What makes you think it's not just a void and filled with nothing?

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Matter
Aug 7, 2019 8:16AM PDT

It is better logic than to make up a substance.

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visible matter as in galaxies - is only 5% mass and energy
Aug 3, 2019 4:40PM PDT

(approx.) last time I checked. Dark matter is detectable from surveys of galaxy rotation curves and galaxy cluster movement analysis - it is inferred because otherwise the rotation rates actually seen would not make sense from a gravitational standpoint from just what mass is _known_ from stars, gas, interstellar and "halo" objects - all this data from visible light (stars) plus radio telescope data (gas, molecular and otherwise such as ionized gas (single atoms stripped of electrons). Sooo, the idea is there must be "dark" matter around galaxies big and small to hold it all together - rotation rates are too fast to be explained by "normal" interacting matter, thus *something* that does not interact or is otherwise visible or detectable is there. We _only_ know about it from the mismatch between what the rotation rates should be and what is actually observed.

The dark matter is around 27% of total mass of the galaxies, clusters, everything in the universe. The unknown form (really unknown!) of dark "energy" - is 68% added to this makes 85% total mass plus dark matter = 95% mass - energy content. this leaves what we *used to* think of everything as only 5%. The Wikipedia article goes into far more detail about
how astrophysicists figured all this out - quite recently, I should add!

Anyway, now that that's as clear as mud, I'll bow out... :^)

Rick " I'm still stuck trying to wrap my brain around time-space " Jones

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(NT) "In the beginning God ..."
Aug 3, 2019 5:10PM PDT
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5%
Aug 7, 2019 8:23AM PDT

Dark matter a theory to excuse logic.

Atoms, for example, (matter) that makes up a solid detectable 'body' is 0.000000001% matter - but solid, detectable and heavy - such as a boulder.

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I'm of the same mind -
Aug 7, 2019 2:58PM PDT

to me, the theories that account for the discrepancies through modified forms of general relativity (and other theories, too) are much more plausible to me, but run into huge difficulties accounting for the data recorded. To physicists, the "elegant" solutions are the "best" - and so rewarded with more support.

But I'm reminded of the notion that the Universe is under no stricture to be comprehensible to _us_ at all... :^)

Rick

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Elegant is used in maths as well.
Aug 7, 2019 3:14PM PDT

Among other things, it means 'no kluges to make it work'.
Stuff Ockham would like.

More than once I've seen scientists say that some natural phenomena is elegant.
Stuff Jehovah would like. "And he saw that it was good ..."

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Forgot. Add "no kluges".
Aug 7, 2019 3:16PM PDT

Unlike today's physics and cosmology. Grin

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Hmm, thought it was spelled Kludge ?
Aug 7, 2019 3:38PM PDT

But yes, I'm aware of William and his 'razor'. Works well most of the time, but not always...

Rick

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That's correct, even unto the capital K.
Nov 8, 2019 3:17PM PST

kluge is cited as secondary by my go-to, the American Heritage Dictionary.
Go-thou-to and read for thyself for an interesting story. Given that, kluge can't ever have been correct.

Having spent much of my work life making and fixing Kludge-like devices, including a couple of copier paper-feeders, I appreciated the information. Thanks.

Wasn't ignoring my mistake; just missed the chance back in August.

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and also
Aug 7, 2019 7:05PM PDT

Acts 17:28 'For in Him we live and move and have our being.'

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Good point.
Aug 7, 2019 3:09PM PDT

I've always marveled at the apparent contradiction. A brick is mostly space, but it will break your head.
The answer is simple. The subatomic forces at work make it seem solid.

Except, that explanation isn't that simple, is it?
"In the beginning God created the heavens and the earth", just don't ask me how. Happy

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(NT) And I'm still waiting on those potholes, geniuses!
Aug 7, 2019 3:05PM PDT
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Update.
Nov 8, 2019 3:22PM PST

My small community has become the only one in the county with no potholes. Good job, guys!
I'll have to find another illustrative complaint.

You can be sure I will.

Grin

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Nothing wrong with inference BTW.
Nov 7, 2019 1:35PM PST

In ancient times, using eyeballs as tools, looking at the earth, most inferred flatness. A few inferred circle or sphere.
It was better observation that settled it.
Except on breitbart. Grin

One who didn't have either the physical viewpoint or the maths said 'circular' or 'spherical'. Isa 40:22.
Another, much earlier, flatly contradicted good inferencing of the day. No doubt lost tenure as a result. Job 26:7

Post was last edited on November 7, 2019 6:01 PM PST

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Maybe it's just invisible or "see through"...
Aug 3, 2019 5:35PM PDT

....like water, as the Bible says.

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Good answer as it is _almost_ "not there" -
Aug 4, 2019 6:54PM PDT

similar in some respects to neutrinos, which can and do pass through ordinary matter like it is not even there! ...

Rick

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Not a bad analogy, but I think it's because
Nov 7, 2019 1:39PM PST

of the tininess of the neutrino relative to the hugeness of the spaces between.
Which means statistics, not magic or physics. Which means there ought to be an occasional collision. Which means ???

Post was last edited on November 7, 2019 2:25 PM PST

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Just A Dark Matter Theory
Nov 7, 2019 7:50AM PST

I have another theory about where dark matter and dark energy comes from. Dark matter is simply real matter that has been subjected to the forces of a black hole. We all know what happens when a black hole overeats, it creates a quasar. Now, who says for absolutely sure a black hole only ejects matter at the time of the of a quasar? My theory is that black holes eject matter continually all the time. It’s been proven that galaxies rotate at the same pace out at the edges as the inner part. It’s like they’re sandwiched between to invisible pieces of bread. The black hole creates converted matter at its north and south poles all the time. Each and every atom of matter is crushed and mixed and stripped of most of its subatomic particles. When these particles are ejected from the black hole, the instantaneously expand at about 10 to the 280 in size. The particles that cause them to reflect light have been destroyed in the black hole. With this many particles coming out and expanding, they create what we call space/time. They are what’s causing the galaxies to speed away from each other so fast because each galaxy has its own black hole. This is called dark energy. You can use the math that measure the speed that the galaxies are moving to figure out how much dark matter is being ejected from all the super massive black holes in the universe. I am not an astronomer nor a physicist but I’m open to other theories.

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Some of us turn to SE for
Nov 7, 2019 1:40PM PST

proof of the existence of dark stuff.
Grin

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For drpruner.
Nov 7, 2019 2:09PM PST
"Mission Accomplished"
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Dark matter
Feb 19, 2020 9:24AM PST

I believe gravity is dark matter and it pushes down on us and not a pulling force. Just putting it out there..?

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I've been following dark matter, but
Feb 19, 2020 12:24PM PST

I just can't see it.