<p>There are (at least) a couple of problems with your hypothesis.</p>

<p>The first problem is that dark matter is just that - dark, in other words it emits no light that we can detect. The exploded remnants of stars are not dark at all. Indeed the winds and superwinds associated with exploding stars are often extremely hot and luminous in the UV and X-ray region. Even when these winds have slowed and cooled, they will then form warm dust (because they are enriched in heavy elements) that is then detectable in the infrared part of the spectrum.</p>

<p>The second problem is that we know that the majority of dark matter is not just non-luminous "normal" matter. Estimates of the cosmic abundances of helium, deuterium and lithium produced in the big bang are sensitive to the overall density of this "normal" matter. These estimates tell us that only about 20% of the gravitating matter that appears to be required to explain the dynamics of the universe, the dynamics of galaxy clusters and the dynamics of galaxies, can be in the form of "normal" matter. But the atoms and particles released from an exploding star are just part of this "normal" matter budget - they have already been accounted for and so contribute nothing to solving this second dark matter problem.</p>

CC BY-SA 4.0
2018-02-05T16:51:38.817Z
2018-11-03T19:56:45.450Z
2018-11-03T19:56:45.450Z
ProfRob
<h3>Newton's shell theorem explicitly contradicts this hypothesis</h3>
<p><a href="https://en.wikipedia.org/wiki/Shell_theorem" rel="nofollow noreferrer">Newton's shell theorem</a> would seem to most directly comment on this hypothesis.</p>
<p>Historically, this theorem was instrumental in providing motivation to support <a href="https://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation" rel="nofollow noreferrer">Newton's theory of gravity</a>, which at that time was a speculative model that physicists around Newton's time were considering following <a href="https://en.wikipedia.org/wiki/Hooke%27s_law" rel="nofollow noreferrer">Hooke's model for springs</a>.</p>
<p>A central premise of the shell theorem is that shells cancel out their own internal gravity.  For example, a perfectly spherical planet would be expected to have zero gravity as its center.  Also, Earth's gravity gets weaker as the center is approached.</p>
<p>So, say that a star explodes.  Then according to Newton's law of gravity, the exploding shell should have zero gravitational pull within it.</p>
<h3>This hypothesis would likely be modified Newtonian dynamics</h3>
<p>For more information on alternative theories of gravity, Wikipedia's article on <a href="https://en.wikipedia.org/wiki/Modified_models_of_gravity" rel="nofollow noreferrer">&quot;<em>Alternatives to general relativity</em>&quot;</a> may be helpful.</p>
<p>In particular, this hypothesis would likely be described as <a href="https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics" rel="nofollow noreferrer"><em>modified Newtonian dynamics</em> (MOND)</a> since it explicitly contradicts Newtonian mechanics.</p>

CC BY-SA 3.0
2018-02-05T06:53:19.790Z
Thank you @Nat.  The page on Newton's shell theorem was informative.  It seems that any object outside of the exploded shell would still feel the full force of gravity as though the object had not exploded at all. I don't know how long it would take for a galaxy to become enveloped by a nova star's expanding shell.  It seems like my hypothesis could still be explained using Newtonian physics and General Relativity.
Rob Erwin
CC BY-SA 3.0
2018-02-05T16:55:51.643Z
I don't see how this addresses the question (about dark matter) at all. There is nothing wrong with applying the shell theorem here. The gravitational effect of a (spherically symmetric) exploded star can indeed by modelled as if all the mass were situated at the centre of mass. The gravitational field is not zero at the centre of the shell because there is a field (of course) produced by all the other mass in the universe.
ProfRob
CC BY-SA 3.0
2018-02-04T09:52:37.883Z
2018-02-04T10:13:34.207Z
2020-06-17T09:47:40.653Z
Nat
<p>I've hypothesized for many years in my head that dark matter are the gravitational after effects of objects that have exploded. My understanding of physics is that when an object explodes, its center of mass remains in the same location. If that's the case, it seems that the gravity of that center of mass could remain. What observations or theories are there that counteract this hypothesis?</p>

CC BY-SA 3.0
2018-02-03T23:47:15.980Z
What object that have exploded are you thinking about? Remember that there is much more dark matter than visible matter in the universe.
James K
CC BY-SA 3.0
2018-02-04T12:09:41.433Z
The wiki page on dark matter has a few discussion points there: https://en.wikipedia.org/wiki/Dark_matter#Observational_evidence
AtmosphericPrisonEscape
CC BY-SA 3.0
2018-02-04T14:28:47.283Z
I think Rob's answer to [How is dark matter different from visible matter](https://astronomy.stackexchange.com/questions/24139/how-is-dark-matter-different-from-ordinary-visible-matter) answers this.
James K
CC BY-SA 3.0
2018-02-04T15:10:11.177Z
And how would you make all this exploded matter invisible (i.e. dark)?
ProfRob
CC BY-SA 3.0
2018-02-05T06:42:56.447Z
@JamesK, I'm thinking mostly of Nova stars.  It seems that more massive stars have shorter lifetimes.  Perhaps this could account for more matter being dark.
[StellarEvolution]: https://en.wikipedia.org/wiki/Stellar_evolution
Rob Erwin
CC BY-SA 3.0
2018-02-05T07:35:45.897Z
@RobJeffries, I was thinking that the exploded matter would be too minute and too dispersed to detect, but I see now that Nova stars become detectable Nebula.  
I was also thinking that gravity located at the center of mass of a large number of small objects could account for "massless" starter black holes at the center of galaxies, but shell theory would seem to counteract that.
Thanks to everyone for helping me through this hypothesis.
Rob Erwin
<gravity><dark-matter>
Dark matter virtual objects hypothesis
Rob Erwin
# Dark matter virtual objects hypothesis

(Asked by: username_0 on 2018-02-03)

I've hypothesized for many years in my head that dark matter are the gravitational after effects of objects that have exploded. My understanding of physics is that when an object explodes, its center of mass remains in the same location. If that's the case, it seems that the gravity of that center of mass could remain. What observations or theories are there that counteract this hypothesis?

**Tags:** gravity, dark-matter

> **Comments:**
> **username_1**: What object that have exploded are you thinking about? Remember that there is much more dark matter than visible matter in the universe.  
> **username_2**: The wiki page on dark matter has a few discussion points there: https://en.wikipedia.org/wiki/Dark_matter#Observational_evidence  
> **username_1**: I think Rob's answer to [How is dark matter different from visible matter](https://astronomy.stackexchange.com/questions/24139/how-is-dark-matter-different-from-ordinary-visible-matter) answers this.  
> **username_3**: And how would you make all this exploded matter invisible (i.e. dark)?  
> **username_0**: @username_1, I'm thinking mostly of Nova stars.  It seems that more massive stars have shorter lifetimes.  Perhaps this could account for more matter being dark. [StellarEvolution]: https://en.wikipedia.org/wiki/Stellar_evolution  
> **username_0**: @RobJeffries, I was thinking that the exploded matter would be too minute and too dispersed to detect, but I see now that Nova stars become detectable Nebula.   I was also thinking that gravity located at the center of mass of a large number of small objects could account for "massless" starter black holes at the center of galaxies, but shell theory would seem to counteract that. Thanks to everyone for helping me through this hypothesis.  

---

## 2 answers

### Answer by username_3 on 2018-02-05. Score: 2

There are (at least) a couple of problems with your hypothesis.

The first problem is that dark matter is just that - dark, in other words it emits no light that we can detect. The exploded remnants of stars are not dark at all. Indeed the winds and superwinds associated with exploding stars are often extremely hot and luminous in the UV and X-ray region. Even when these winds have slowed and cooled, they will then form warm dust (because they are enriched in heavy elements) that is then detectable in the infrared part of the spectrum.

The second problem is that we know that the majority of dark matter is not just non-luminous "normal" matter. Estimates of the cosmic abundances of helium, deuterium and lithium produced in the big bang are sensitive to the overall density of this "normal" matter. These estimates tell us that only about 20% of the gravitating matter that appears to be required to explain the dynamics of the universe, the dynamics of galaxy clusters and the dynamics of galaxies, can be in the form of "normal" matter. But the atoms and particles released from an exploding star are just part of this "normal" matter budget - they have already been accounted for and so contribute nothing to solving this second dark matter problem.


---

### Answer by username_4 on 2018-02-04. Score: 1

### Newton's shell theorem explicitly contradicts this hypothesis

[Newton's shell theorem](https://en.wikipedia.org/wiki/Shell_theorem) would seem to most directly comment on this hypothesis.

Historically, this theorem was instrumental in providing motivation to support [Newton's theory of gravity](https://en.wikipedia.org/wiki/Newton%27s_law_of_universal_gravitation), which at that time was a speculative model that physicists around Newton's time were considering following [Hooke's model for springs](https://en.wikipedia.org/wiki/Hooke%27s_law).

A central premise of the shell theorem is that shells cancel out their own internal gravity. For example, a perfectly spherical planet would be expected to have zero gravity as its center. Also, Earth's gravity gets weaker as the center is approached.

So, say that a star explodes. Then according to Newton's law of gravity, the exploding shell should have zero gravitational pull within it.

### This hypothesis would likely be modified Newtonian dynamics

For more information on alternative theories of gravity, Wikipedia's article on ["*Alternatives to general relativity*"](https://en.wikipedia.org/wiki/Modified_models_of_gravity) may be helpful.

In particular, this hypothesis would likely be described as [*modified Newtonian dynamics* (MOND)](https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics) since it explicitly contradicts Newtonian mechanics.

> **Comments:**
> **username_0**: Thank you @username_4.  The page on Newton's shell theorem was informative.  It seems that any object outside of the exploded shell would still feel the full force of gravity as though the object had not exploded at all. I don't know how long it would take for a galaxy to become enveloped by a nova star's expanding shell.  It seems like my hypothesis could still be explained using Newtonian physics and General Relativity.  
> **username_3**: I don't see how this addresses the question (about dark matter) at all. There is nothing wrong with applying the shell theorem here. The gravitational effect of a (spherically symmetric) exploded star can indeed by modelled as if all the mass were situated at the centre of mass. The gravitational field is not zero at the centre of the shell because there is a field (of course) produced by all the other mass in the universe.  

---

