Dark Matter explained away.

New Scientist has reported that University of Waterloo physicists have released a gravitational variant that doesn't require dark matter (or at least as much of it) and explains a few weird effects that otherwise aren't well explained. The other advantage of the theory is its resurrectance of the graviton, which if it exists would create a whole new (valid) field of mathematics in dealing with spin-2 particles (the few articles that exist read more like apologies). It would also vastly reduce the requirement for Dark Matter, which despite the fears of some I would gladly welcome. I did a project on dark matter back in my undergrad physics days, and kept running into the great two hurdles of dark matter:

Firstly, its relatively rare, making up maybe some 10% of the matter out there. Problem is that the theory calls on 23% dark matter, or worse: 85-90%. There just isn't that much out there. WIMPS have to take up way too much of the slack, and the best WIMP candidate out there is the neutrino, which may end up having zero rest mass anyways. If the neutrino does have mass, then we have more neutrino flavours to come up with since the detection of neutrinos so far has come up short of the required total. If that's not enough, the MACHOs have the massive requirements for dark matter, but there just aren't enough of them out there, unless we're missing out on lots of them [which isn't that unreasonable, seeing how they are dark! -ed]. But we can't be missing lots of them, because there are only so many baryons available to be missing out on, and we aren't really missing out on them. So between the two possibilities (and we can't think of a third candidate between things small and almost massless and numerous and things large-ish and massive and light absorbing) dark matter just doesn't seem to be around as much. The dark energy theory was brought in to fill some of the gaps, which brings us to...

The second problem with dark matter is that its coming across far too much as a "fudge factor". You have to start bringing in negative pressure [of course, they once scoffed at negative mass -ed] and even poetic notions such as "cost of (free) space" simply don't carry a whole lot of weight. The dark matter problem is almost a bit of scientific desperation, trying to explain away holes in logic with dark matter plugins. While I don't doubt there is dark matter out there (here's a real-life MACHO and here are real-life WIMPS) there just isn't that much of it, and not a heck of a lot of dark energy either.

So the Scalar-Tensor-Vector Gravity development might seem pretty exciting. (Stupid name though. Basically its called "1-n-3 dimension gravity" or worse, "1-n^2-n dimension graviity") It does already have its share of detractors, and the hard questions still haven't been asked. Of course, its a good time to mention that as a B.Sc. Physics holder myself, I'm available to anybody who's hiring people to help ask and/or answer these questions!