Comment by staplers
18 hours ago
the lowest mass dark object currently measured
one million times the mass of the Sun
Sometimes you read things that remind you how vast and untamable our universe really is.
18 hours ago
the lowest mass dark object currently measured
one million times the mass of the Sun
Sometimes you read things that remind you how vast and untamable our universe really is.
Yep, this still blows my mind, has a radius of 330 million light years, of, er, nothing (well 60 galaxies compared to what should be several thousand). https://en.wikipedia.org/wiki/Bo%C3%B6tes_Void
sssh, that's where we store the hammers
I think there is a shortcut being taken here.
We are surrounded by dark objects, a rock is a dark object, exoplanets are dark objects, and so are black holes. Pretty much everything but stars are dark objects. They are all dark because they don't emit light.
Here, I think they mean stuff (whatever it is) that can only be detected by gravitational lensing, and it makes sense that it has to be extremely heavy, because gravity is so weak.
I'm not a physicist but every definition of dark matter that I read says it does not interact with electromagnetic radiation hence it is invisible, and rocks are not that dark matter (wiki. NASA, etc)
So how do we know that these "dark matter objects" aren't actually just massive collections of normal matter that is dim enough and at such a far distance that it would appear (angular resolution-wise) to be invisible, but we can still detect the lensing?
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> ... every definition of dark matter that I read says it does not interact with electromagnetic radiation ...
Actually, dark matter does interact with electromagnetic radiation -- it can deflect it, as in the case of gravitational lensing. But dark matter doesn't either emit nor absorb electromagnetic radiation directly.
We only know about dark matter because of its gravitational effects.
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yeah all those other things absorb light so they can be detected by the light they block and the infrared light the re-emit.
Dark matter seems more ghostly , like gravitational shadow of matter
If you think that's crazy, it's likely a drop in the bucket comared to the noumenonal world.
There's no reason to think that our senses encompass the vast majority of understanding everything in reality and current evidence that they, in fact, do not, via dark matter as a primary source.
I suspect our senses encompass a meaningless fraction of the noumenon.
In what way is dark matter not a phenomenon? Just because we don't know what it is doesn't make it a noumenon.
It's that it demonstrates that some sort of noumenon can likely have partial but not 'full' overlap as we understand it with a phenomenon.
To elaborate, the noumenon can have properties that are unknown to us and outside the purview of certain senses (if not all) but still have partial phenomenal effects such as gravitational effects.
Given partial overlap, we could, and likely should, surmise that overlap, if partial, can also be zero. In fact, partial overlap with certain things (such as the gravitational field) but no sensory experience is exactly what we'd predict if this were true.
The mistake is thinking I'm asserting that things are phenomenon or noumenon when that's not quite right. Mostly, the supposition is that things can exist and have either 'full' (unlikely I think), partial, or zero overlap with our sensory experience. Things that demonstrably have partial overlap suggest a wider world of things. I simply find the idea that our evolved sensory experience encompass even a sizable fraction of reality to lack epistemic humility.
This is obviously speculative.
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