I Dark Matter: Can Gravitational Field Be Generated?

[Lorenzo Mambretti]

The dark matter is described as something which can't be detected in any way except for its gravitational attraction.

My question is: may the dark matter be identified with gravitational field generated by the presence (for short times) of matter and anti-matter which is continually created and annihilated in vacuum space?

Because I know that some studies shows that this process take place, and it can be measured for its energy as "vacuum energy", but I would like to know if effectively it can also generate a gravitational field.

Thank you in advance

 

[DrChinese]

My question is: may the dark matter be identified with gravitational field generated by the presence (for short times) of matter and anti-matter which is continually created and annihilated in vacuum space?

If that were the case, it could not have a presence such as it does. I.e. there would be no dark matter maps such as per the below article.

http://www.space.com/29085-dark-matter-maps-unknown-universe.html

 

[ohwilleke]

No. Matter and anti-matter pair creation, or annihilation doesn't violate conservation of mass-energy. It just changes the form of mass-energy. And, all mass-energy gravitates. Moreover, matter-antimatter pairs have electromagnetic charge.

 

[mfb]

the presence (for short times) of matter and anti-matter which is continually created and annihilated in vacuum space?

There is no such thing. That is just a pop-science myth.

and it can be measured for its energy as "vacuum energy"

Dark energy (which has nothing to do with dark matter apart from the similar name) is probably an energy density of the vacuum (which has a gravitational effect), but it has nothing to do with particle/antiparticle pairs. There is a way to guess its density via quantum field theory, but that leads to a value that is too high by 120 orders of magnitude, so clearly that approach does not work.