<p>No, &quot;dark fluid&quot; is not a synonym for dark matter.</p>
<p>The Daily Mail article derives from a <a href="http://actu.epfl.ch/news/galaxy-clusters-collide-dark-matter-still-a-myst-2/" rel="nofollow noreferrer">press release by the EPFL</a> and an article in <a href="http://science.sciencemag.org/content/347/6229/1462.full" rel="nofollow noreferrer">Science magazine</a>, neither of which mention the word 'fluid'.</p>
<p>We don't know what dark matter is yet. There are several theories. <a href="http://www.digitaljournal.com/science/is-dark-matter-a-fluid-its-particles-aren-t-particles-at-all/article/429310" rel="nofollow noreferrer">One of them</a> compares dark matter to a fluid:</p>
<blockquote>
<p>Normally speaking, subatomic particles exchange momentum when they interact. Consequently, galactic collisions should also lead to interaction by dark matter particles and by studying it, we would have a better idea of what dark matter really is.</p>
<p>To verify whether dark matter is made up of particles, the researchers explored two possible outcomes. The first, was that particles of dark matter often interact, but don't exchange much momentum. The second was that they seldom interact, but exchange a lot of momentum.</p>
<p>If the first case was true, dark matter would slow down after the collision, since the greater frequency of the interactions would have drag-like effect. If the second case was proven to be true, then dark matter would likely be dispersed into space.</p>
<p>Surprisingly, the study discovered that the dark matter particles from two colliding galaxies, simply pass through each other, suggesting that dark matter particles do not interact with themselves, <em>but have a more fluid-like character instead</em>.</p>
</blockquote>
<p>(emphasis mine). So they're not saying dark matter is exactly like a fluid, they're saying dark matter has some properties that are comparable to the behavior of fluids.</p>

CC BY-SA 3.0
2016-06-14T14:42:39.650Z
(second yellow text insert)" ‘Alternatively, dark matter could be some kind of fluid, rather than a particle with a property in space,’ Dr Massey said. Read more: dailymail.co.uk/sciencetech/article-3013284/… Follow us: @MailOnline on Twitter | DailyMail on Facebook – NormLDude Jun 9 at 14:55
NormLDude
CC BY-SA 3.0
2016-06-14T14:57:59.447Z
In my opinion, it is likely the Daily Mail writer interviewed a scientist and misunderstood the point the scientist was making. None of the original sources referred to a fluid.
Hobbes
CC BY-SA 3.0
2016-07-05T19:59:57.397Z
@NormLDude The day people use the Daily Mail as a source of factual information, especially as regards any science topic, is the day that they lose all sense of reality.
Simon
CC BY-SA 3.0
2016-06-09T17:04:26.907Z
2016-06-09T17:04:26.907Z
2020-06-17T09:47:40.653Z
Hobbes
<p>Is this term official jargon/wording for 'Dark Matter'?
If so, why include the word "Fluid" if there is supposedly no viscosity in actual space. It would be like saying 'Hey, want to go swim in my 'gravel' pool?"
<a href="http://www.dailymail.co.uk/sciencetech/article-3013284/Is-dark-matter-FLUID-Mystery-particles-mapped-galaxy-clusters-results-suggest-not-particles-all.html" rel="nofollow">http://www.dailymail.co.uk/sciencetech/article-3013284/Is-dark-matter-FLUID-Mystery-particles-mapped-galaxy-clusters-results-suggest-not-particles-all.html</a></p>

CC BY-SA 3.0
2016-06-09T14:55:38.813Z
(second yellow text insert)" ‘Alternatively, dark matter could be some kind of fluid, rather than a particle with a property in space,’ Dr Massey said. 

Read more: http://www.dailymail.co.uk/sciencetech/article-3013284/Is-dark-matter-FLUID-Mystery-particles-mapped-galaxy-clusters-results-suggest-not-particles-all.html#ixzz4B5uIb6A7 
Follow us: @MailOnline on Twitter | DailyMail on Facebook
NormLDude
CC BY-SA 3.0
2016-06-09T15:17:35.620Z
I'm on my first cup of 'dark fluid' right now ... let me give this some thought.
Howard Miller
CC BY-SA 3.0
2016-06-09T15:20:49.820Z
Fluid is a really weird choice of terminology; fluid matter interacts with solid or fluid matter, it doesn't "pass through it" in a galactic-scale collision.
Russell Borogove
CC BY-SA 3.0
2016-06-09T15:32:06.553Z
https://en.wikipedia.org/wiki/Dark_fluid
aventurin
CC BY-SA 3.0
2016-06-09T15:47:59.863Z
@aventurin I think that is a separate concept. It appears that the linked article is just trying to posit that dark matter may be something closer to a fluid than a collection of individual particles.
zephyr
<dark-matter>
What is 'Dark Fluid'?
NormLDude
# What is 'Dark Fluid'?

(Asked by: username_0 on 2016-06-09)

Is this term official jargon/wording for 'Dark Matter'?
If so, why include the word "Fluid" if there is supposedly no viscosity in actual space. It would be like saying 'Hey, want to go swim in my 'gravel' pool?"
<http://www.dailymail.co.uk/sciencetech/article-3013284/Is-dark-matter-FLUID-Mystery-particles-mapped-galaxy-clusters-results-suggest-not-particles-all.html>

**Tags:** dark-matter
> **Comments:**
> **username_0**: (second yellow text insert)" ‘Alternatively, dark matter could be some kind of fluid, rather than a particle with a property in space,’ Dr Massey said.   Read more: http://www.dailymail.co.uk/sciencetech/article-3013284/Is-dark-matter-FLUID-Mystery-particles-mapped-galaxy-clusters-results-suggest-not-particles-all.html#ixzz4B5uIb6A7  Follow us: @MailOnline on Twitter | DailyMail on Facebook  
> **username_1**: I'm on my first cup of 'dark fluid' right now ... let me give this some thought.  
> **username_2**: Fluid is a really weird choice of terminology; fluid matter interacts with solid or fluid matter, it doesn't "pass through it" in a galactic-scale collision.  
> **username_3**: https://en.wikipedia.org/wiki/Dark_fluid  
> **username_4**: @aventurin I think that is a separate concept. It appears that the linked article is just trying to posit that dark matter may be something closer to a fluid than a collection of individual particles.  

---

## 1 answers

### Answer by username_5 on 2016-06-09. Score: 2

No, "dark fluid" is not a synonym for dark matter.

The Daily Mail article derives from a [press release by the EPFL](http://actu.epfl.ch/news/galaxy-clusters-collide-dark-matter-still-a-myst-2/) and an article in [Science magazine](http://science.sciencemag.org/content/347/6229/1462.full), neither of which mention the word 'fluid'.

We don't know what dark matter is yet. There are several theories. [One of them](http://www.digitaljournal.com/science/is-dark-matter-a-fluid-its-particles-aren-t-particles-at-all/article/429310) compares dark matter to a fluid:

> Normally speaking, subatomic particles exchange momentum when they interact. Consequently, galactic collisions should also lead to interaction by dark matter particles and by studying it, we would have a better idea of what dark matter really is.
>
> To verify whether dark matter is made up of particles, the researchers explored two possible outcomes. The first, was that particles of dark matter often interact, but don't exchange much momentum. The second was that they seldom interact, but exchange a lot of momentum.
>
> If the first case was true, dark matter would slow down after the collision, since the greater frequency of the interactions would have drag-like effect. If the second case was proven to be true, then dark matter would likely be dispersed into space.
>
> Surprisingly, the study discovered that the dark matter particles from two colliding galaxies, simply pass through each other, suggesting that dark matter particles do not interact with themselves, *but have a more fluid-like character instead*.

(emphasis mine). So they're not saying dark matter is exactly like a fluid, they're saying dark matter has some properties that are comparable to the behavior of fluids.

> **Comments:**
> **username_0**: (second yellow text insert)" ‘Alternatively, dark matter could be some kind of fluid, rather than a particle with a property in space,’ Dr Massey said. Read more: dailymail.co.uk/sciencetech/article-3013284/… Follow us: @MailOnline on Twitter | DailyMail on Facebook – NormLDude Jun 9 at 14:55  
> **username_5**: In my opinion, it is likely the Daily Mail writer interviewed a scientist and misunderstood the point the scientist was making. None of the original sources referred to a fluid.  
> **username_6**: @NormLDude The day people use the Daily Mail as a source of factual information, especially as regards any science topic, is the day that they lose all sense of reality.  

---

