problem with modified Newtonian dynamics

Wait- this could be relevant! How would you visualize the following?
(or why)

Gravity conundrum

• 20 May 2006 by Robert Barclay, Glasgow, UK
• Magazine issue 2552.

It strikes me that modified Newtonian dynamics (MOND) still has two problems, despite being reformulated to be compatible with general relativity (29 April, p 52). First, there is still no clear physical basis for the theory; and second, unless the reformulation has changed some of MOND's predictions, it fails to cope with very large-scale situations - such as the behaviour of large galaxy cluster cores.

Dark matter has problems too. No one knows what it is made of, and no one has ever found any. What's more, as MOND has highlighted, there is a consistent pattern to its distribution within galaxies that hasn't been explained.

A resolution to all these problems would come from a source of mass (or equivalent energy) that is potentially present everywhere, is not normally detectable and could be brought into being due to the mass of baryonic matter in galaxies. It seems to me that the obvious candidate is vacuum energy, in the form of virtual particles, that pervades space.

From Tim Hely

The addition of two extra fields in the TeVeS model of modified Newtonian dynamics reminds me of the addition of epicycles in the flawed geocentric theory of the solar system. I predict with some confidence that the model will fit the data even better if we keep adding on extra fields. Why stop at only three? Why not choose four, five - or even 11 to match the number of dimensions in M-Theory? Unfortunately, I believe that our understanding of the astronomical processes involved will vary inversely with the number of fields required.

Edinburgh, UK

note from ann: how many dimensions are we prepared to work with?

1 point in space

2 line

3 z-space (a cube)

4 time

5 sound ( I may have made this one up)