To explain the "dark matter" phenomena, there is also a much weirder explenation.

Let us for example assume that - like the electric charge, which can be positve and negative - there exist also postive and negative mass. Current physics regards that (based on quantum theory, I guess) as unphysical. But suppose that is wrong. How would that change the picture?

Well, the negative mass matter would have some weird properties.

Gravitationally, it would mean that like masses have an attractive force, and unlike masses and repulsive force. However, taken that the inertial mass is equal to the gravitational mass, the acceleration of negative mass would be in the opposite direction in which the force is applied!

This would mean:

- positive masses accelerate towards each other

- negative masses accelerate away from each other (like a repulsive force on positive matter)

- a positive mass would accelerate away from a negative mass, but a negative mass would accelerate towards a positive mass!

There have been done some theoretical studies on this, for example by Bondi.

See for example

this paper.

The paper suggests that the positive/negative mass pair would not actually chase each other but would perform what is called a "zitterbewegung".

Suppose we have intially both positive and negative mass matter. What would occur?

The positive mass matter would gravitationally bind together.

The negative mass matter would spread out and dilute itself initially. But because negative mass matter still is accelerating towards positive mass matter, it would accumulate in a halo around clusters of positive mass matter.

Note also that the attraction/repulsion for the electric force for negative mass matter is opposite to that of positive mass matter: like charges would accelerate towards each other (like an attractive force for positive mass matter) and unlike charges would accelerate away from each other (like a repulsive force for positive mass matter).

So this would give some weird interference between positive and negative mass matter, both gravitationally and electrically!

However, the existence of negative mass matter has not been confirmed, and is clearly outside of the "standard model".

Only thing is I think they do need to try to model it, and see if that explains all the anomalous gravitational phenomena that used to be attributed to dark matter.

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Some papers on this:

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NB. "negative mass matter" is not the same as "anti-matter" because the latter is just a charge-symetry (opposite charge as normal matter) but with positive mass. That is why it costs energy to create a matter/enti-matter particle and annihilation of such a pair, creates energy. A positive/neagative mass pair of equal absolute magnitude would cost no energy.

See also:

this page,