How can distinguish conves and concave gravitational lensing effect?

[icarus2]

How can distinguish conves and concave gravitational lensing effect?

 

Generally, it is possible to examine the existence of dark matter with the existence of additional mass with the effect of gravitational lensing. If negative mass is dark matter, so if we try to examine the effect of gravitational lensing, previously the gravity between positive mass is attraction, so it has the shape of convex lens to collect within the form, whereas the force between negative mass and positive mass is repulsion, so a set of massive negative mass can make the effect that distorts observation target in the form of concave lens.

 

 

If existing measuring instrument recognizes the effect of gravitational lens with distorted aspect of galaxy or galaxy cluster, the effect of concave gravitational lensing owing to the existence of negative mass also plays a role of distorting galaxy or galaxy cluster, so it can be the basis of invisible dark matter. Additionally, in the distribution of dark matter suggested with previously measured effect of gravitational lens, dark matter may be created purely by positive mass, but also it can be created by the distribution of dark matter by negative mass.

 

 

But in the hypothesis of dark matter with negative mass in this study, negative mass is distributed out of galaxy, not within galaxy. Therefore, the effect of concave gravitational lensing by negative mass out of galaxy will be presented to an observer on the earth in the same form as the effect of convex gravitational lensing which galaxy works.

 

 

fig19.Concave Gravitational lensing effect.

The left side is the Gravitational lensing effect that occurs when the galaxy is surrounded by negative mass and the right side is Gravitational lensing effect that occurs when positive mass exists alone

 

 

No the effect of concave gravitational lensing by negative mass has been observed. However, we have never thought about negative mass itself, so we might not have thought about the concave gravitational lensing as well, and it might be difficult to classify the effect of concave gravitational lensing and the effect of convex gravitational lensing.

 

For the situation presented on the left when observing the light on the earth which passed through galaxy surrounded with negative mass, this study suggested that there is invisible dark matter in galaxy, and owing to this gravity it can be happened owing to the effect of convex lens, it means, if there is any matter on the left and right side of galaxy that plays a role of concave lens, it is difficult to classify convex lens and its form.

 

According to the explanation of the effect of concave gravitational lensing from the viewpoint of gravity, not geometrical optics, there is the effect of centripetal force by the distribution of negative mass out of galaxy with the effect of centripetal force in galaxy as described previously, so there is real mass of galaxy plus the gravity when filling the whole galaxy with positive mass that has the same density as that of negative mass in galaxy. Therefore, if the light from the exterior passes inside of galaxy or near galaxy, real gravity of galaxy plus gravity of dark matter(by negative mass) is added, and finally it will present much greater effect of gravitational lensing.

 

 

If we consider the situation that we can observe purely the effect of concave gravitational lensing, that situation is just the same as the situation when there is single concave lens on the right in Figure above.

 

 

First, an observer on the earth must observe it on Position B and C after moving by considerably great distance as compared with the size of galaxy, but the earth has never changed the position of observation from the target for distant observation.

 

second, real observation on the earth is the single B or C situation in Figure on the right, and if an observer on the earth performed observation previously on C, generally an observer of C would describe the effect of gravitational lensing is generated because there is invisible dark matter on the right of black and white area(circle drawn with dotted line on the right).

 

 

As observed the effect of concave gravitational lensing, this can be the evidence for the existence of negative mass.

 

 

I had read below paper.

Charles R. Keeton1(June 2002), [ A Catalog of Mass Models for Gravitational Lensing ]

http://arxiv.org/abs/astro-ph/0102341v2

 

While composite models provide a great deal of freedom and complexity, they are not completely general. This limitation is eliminated in the elegant algorithm by Saha & Williams (1997; also Williams & Saha 2000) for finding non-parametric lens models. The approach is to introduce a set of mass pixels and construct a large linear programming problem for determining their masses.

 

The problem is severely underconstrained, but by requiring positive-definite masses and imposing some smoothness criteria it is possible to find a wide but finite range of non-parametric models consistent with the data.

 

A limitation of the Saha & Williams algorithm is that the constraint of a positive-definite surface density is weaker than the constraint of a positive 3-d mass density — or,better yet, a positive-definite quasi-equilibrium distribution function. In other words, while parametric models may provide too little freedom, the Saha & Williams non-parametric models provide too much. For example, their method does not determine whether models are consistent with stellar dynamics, and many of the models found by the method probably are not consistent.

 

Maybe, Gravitational lensing method has not distinguish positive mass and negative mass.

 

 

How can distinguish conves and concave gravitational lensing effect at the Earth?

 

If some gravitational lensing method can distinguish it, please know to me.

Paper and article!

Edited December 13, 2009 by icarus2

[steevey]

You look at the surrounding masses. As you've showed in the pictures, there are two different scenarios which light can be bent. And generally, physicists will be able to see those surrounding bodies of matter bending light the specific way that it does.

[alpha2cen]

 

fig19.Concave Gravitational lensing effect.

The left side is the Gravitational lensing effect that occurs when the galaxy is surrounded by negative mass and the right side is Gravitational lensing effect that occurs when positive mass exists alone

 

From the left side Figure, if there were a vacant space instead of Galaxy, and the empty space had no pass to travel the light and not absorbed the light, what kind of phenomena would happen?

1) The light could not be passed because of the empty space.

2) The light would be bended to the passable way.

Edited February 7, 2011 by alpha2cen

[IM Egdall]

OK, so waht is "negative" mass? Is there any evidence for it? Or is it just theoretical?