Mass of a galaxy without dark matter and with dark matter

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wabbit

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I didn't read his post as calling you stupid , but saying the way he initially understood it sounded stupid. OP is clearly not using his first language here.
 
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If you don't like what I said, provide a counterexample or counterargument, or at least ask a question. Don't just call it stupid. It's not just unhelpful. It's rude.

If you bothered to type "dark matter rich galaxies" in Google, you would have gotten 70,600 hits. If I were you, I'd do a bit more research before telling other people that they are wrong.
I didnt tell you stupid.If you understand like that I am very very sorry.

"I didn't read his post as calling you stupid , but saying the way he initially understood it sounded stupid. OP is clearly not using his first language here"

Wabbit is right.I tried to say this idea sounds like stupid And he is right again my first language is not english.
 
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Examples include: http://arxiv.org/abs/astro-ph/0308518, A Dearth of Dark Matter in Ordinary Elliptical Galaxies; and http://arxiv.org/abs/1410.8141, Forty-Seven Milky Way-Sized, Extremely Diffuse Galaxies in the Coma Cluster.
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I read them and I found them interesting.But I want to ask something , this cases are extraordinary but this cannot be the hole story.I want to ask you in generally how DM affects mass of galaxy.Theres 100 billion galaxies generally what can we say ?
 
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The mass of the galaxy is a bit more than the mass of its dark matter. Where "a bit" depends on which galaxy you look at, but it is somewhere around 20% more on average.
Most of the mass in the universe is dark.
 
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Lets suppose we have a galaxy mass 5m then dark matter mass will be 4m then total mass will be 9m so total mass is 2 times bigger then the galaxy mass in the average isnt it ?
 
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"Galaxy mass" includes the dark part.

Your galaxy would (on average) have 4m dark matter and 1m visible matter (more precise: baryonic matter), for a total of 5m. 80% of the 5m are dark.
 
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Ok thanks
 
Checked post # 10, but wonder, has there been a galaxy the Hubble has locked on, that does not have dark matter to some degree? My questions: what is DM and what is its reason for its being, if in fact it exists?
 
O

officialmanojsh

I am curious about mass of a galaxy without dark matter and with dark matter.I searched but I couldnt found.I ll be happy If you help me.

Thanks
There are many Theories which define the start of universe differently. 1 among them say that universe begin with the break down of black holes and would end when entire mass of universe is pulled back by black hole. Yet the reality is undiscovered :)
 
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There are many Theories which define the start of universe differently. 1 among them say that universe begin with the break down of black holes and would end when entire mass of universe is pulled back by black hole. Yet the reality is undiscovered :)
I am not aware of mainstream theories suggesting that. Please give a source for that claim.
 
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That is a news article, I was asking for a peer-reviewed publication (see our forum rules). News articles nearly always get the science wrong. The preprint linked there is not peer-reviewed, and it does not describe what you wrote in your previous post.
 

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