Recent content by Trenton

Whoa! Both very nice documents with a lot to digest, particularly the most recent one. I notice it talks about MOND - a concept I am deeply skeptical of although of course, on galactic scales the expansion of space would begin to creep in as a factor. Plus the above papers will have to be read...

I keep reading articles that assert that spiral galaxies would fly apart if it were not for the presence of a dark matter halo. The observation that rotational speeds vary little with distance from the center is usually cited as the 'proof' of dark matter since this behavior would otherwise...

I too have contemplated this issue at length but too little avail. Firstly as I understand it, it is spacetime that is curved. Space is simply contracted under the stress-energy tensor. Secondly, there appears to be no way of measuring how contracted the space you are in is. Indeed this is the...

Been out of the loop for a while but on this issue, obviously any dark matter outside a formed star would simply fall in, gain speed and then re-escape. But this would be less the case when a gas cloud was coallescing into a star. I remain open on dark matter but I also remain convinced that...

I can't remember who it was that said I should 'learn some physics' instead of playing devil's advocate but I do accept they have a point. I have a physics degree which I just managed to pass by the skin of my teeth with the key problem being the math. My maths is good enough for engineering...

Bruce - yes I am very keen on learning about this whole area but I am coming from a long way behind! I had a similar problem with GR which I have now more or less got on top of. What I found was that the established concepts were largely obscured by strange language that eventually one...

This seems to me a semantic issue. I am not sold on either borrowed energy or virtual particles of negative energy. There is though, one very good and visible example of 'negative energy' on a macroscopic scale - the sudden outflow of water that can occur before a tsunami. The drained area is...

When I was at school I concluded the following:- "A particle in everyday terms, is a 'solid' object of such small radius that it may be considered as having a single x,y,z,t coordinate. A wave is more or less the exact opposite. It is entirely possible for a wave to approximate to and behave as...

I have wondered this also and I read or rather tried to read, the wikipedia article. It leaves or seems to leave more questions than it answers. Both the particle and the anti-particle produced have positive mass-energy and the only counterbalance on offer seems to be that the particles exist...

I was aware of MOND's formula being successful at matching observed galactic rotation. And of course, it should never be forgotten that science is all about formulating theories that match observations. But it lacks consistancy as you say and for me that is a very big hurdle to overcome. But...

For the record I am firmly non-MOND. I remain just about 'open' on the subject of dark matter although I really am baffled as to why nobody seems to think it would all end up in the stars - therby negating its 'purpose' which is to account for missing mass. The only way it could avoid this fate...

I am not qualified to say but anything involving more than 3 spatial dimensions plus time sounds like someone has been watching too much Dr Who. Worse than this string theorists are divided into two camps. One says there are 10 dimensions, the other says 11. Presumably the camp that says 10...

String theory is weird but GR is, when properly explained, quite straightforward. There is a lot in GR that will be of interest to zero net energy theorists. On the dark matter front my last entry inolved a joke that went a bit awry. Not point explaining it now though. However a question to...

A quick note on Gabriel's comments - there is a certain amount of voltage to the zero net universe concept. It has a very deep appeal but I found trying to conceive of a counter balance more mind blowing than GR (which I eventually managed to get my head around). One obvious candidate was the...

I had thought that while the 21 cm line measurments were good for spotting clouds of gas they were not accurate at measuring the mass of such clouds - and that for measuring density of extreamly diffuse gas they were hopelessly inaccurate. I take it this is not the case? Nor did I think the...