Do the three dimensions of space only look linear too? Can you have negative size?
Incidentally you didn't answer this question.
D1, D2 and D3? He is not elaborating on that. In my opinion, negative size will be defined by your postion in a 3D environment. The first three dimensions create boundaries of perception. Whoever will be inside those boundaries, will define the accessible perceived elements as physical reality.
Theoretically, each dimension can be described as a layer, and our reality can be defined by the contact zone of those layers. Each layer penetrates the other layers but is not identified as doing so.
Our lives were contained in this frame of reference for so long that we are generally thinking that is all there is, but is not all there is.
Your question - That is public info at
http://www.mikeblaber.org/ on the left of the page.
I think this professor is playing with the notion of dimensions, like we are racing GT6 at Suzuka in a Fiat 500. I thought you were jumping on conclusions a little. Here you have his Curriculum vita/resume
http://www.mikeblaber.org/cvita.html
If I am trying to achieve something, that will be the same thing he tries to achieve by publishing that info on his website. Some of the GTP members might be interested to figure where this theory is coming form, by not willing to digg it out from the rest of the internet.
it ignores what we already know about the universe
We know very little about our universe, about our brains, about our feelings.
We have a solid understanding of where life comes from
Many will argue that. I think there are more things we don't know about or we do not understand, than viceversa. I support science 100% but I also want to stay honest about our very limited knowledge as humans.
I don't know if life is or is not a dimension. What we understand is defined by our boundaries of perception and physical reality (see above). The rest is theory and theories are limitless.
I want to be clear here, and let you all know how much I appreciate your input. There are few theories about a 5th dimension, and this is one of them. I personally like the concept, because, the more you think of it, the more you can emphasize on how this 5th layer looks like, and what its properties are.
An interesting approach can be the connection between our brains and hearts in relation to our life (D5). D4 (time) is generating experience thru ageing in a constantly changing limited (by the other 3 dimensions) reality. On top of that you have the concept of "spirit", which includes life forms feelings and thoughts. And on top of that you have "dreaming" when your movements are different than real life, and can be associated to a projection from previous individual forms inside life as a dimension.