Recent content by space_cadet

LQG for the Bewildered - arXiv:1402.3586 Hello again, Almost precisely one year to the day that I posted the early draft of lqgbewil in this thread, I present for your reading pleasure the beta-version of lqgbewil submitted to arXiv in Feb, 2014. http://arxiv.org/abs/1402.3586 The...

Actually that is not such a new idea. Gibbons and Hawking wrote a paper in 1977 ("Action Integrals and partition functions in quantum gravity") where they showed that on analytically continuing the time component to imaginary values - and, thus, complexifying the metric - the resulting action...

It would be nice to have a clock showing the server time, in some corner of the page. It would help people in time zones, different from the server's. Just saying. You mean they don't already have MathJAX??! :rolleyes:

In GFT the basic building blocks are (n-1)-simplices (a 0-simplex is a point, a 1-simplex is a line-segment, 2-simplex is a triangle, 3-simplex is a tetrahedron ... and so on), which are glued together to form a simplicial complex (a discretized manifold), whose dynamics is given in terms of...

Thanks Marcus. There won't be much of a culture is no one knows what the heck is going on, right? :-D BTW the line in the paper: "Its a truth universally acknowledged ..." is due to Sundance. Haha. Thanks. Walk into the lion's den, you mean? What do you take me for? David? Gurau...

You're right. There is a bit of a jump. That's partially because of my desire to avoid unnecessarily duplicating content which has already been nicely covered elsewhere, and partially because of lack of ideas. lqgbewil is not meant to be entirely self-contained. Its purpose is to serve as an...

Many thanks to Marcus, Leucippus and others for their kind reviews of our paper. Just to make things clear, I'm Deepak. A couple of points: 1. I used to post as "space_cadet" on physics.stackexchange.com ... until that ecosystem became severely imbalanced and I left for good. The content...

Hopefully it reads nice too :smile: Using the latex package "todonotes".

This seems as good an opportunity as any to introduce a paper I have been working on, along with a collaborator, which is intended as a bare-bones intro to LQG. Since the paper is not quite complete yet, it hasn't been uploaded to arXiv. However, since people seem to show continued interest and...

So what about wave-particle duality then? Also it is true that there is ambiguity in the definition of a particle, but there is also ambiguity in the definition of a field. That's what gauge and diffeomorphism invariance are all about, right? Couldn't we switch the words "particle" and...

That's exactly the point. We are transforming from a basis spanned by { a^\dag_{k\sigma}, a_{k'\sigma}} to a new basis {\alpha^\dag_{k\sigma},\alpha_{k'\sigma}} related to the old one by a linear transformation (Boguliubov transformation). Then requiring that the coefficient of the quartic term...

That's the general idea. I wouldn't pursue this scheme unless I felt that it could lead to a more complete description. There are many streams of thought which combine in this topic ~ quantum hall effect, black hole entropy and quantum computing to name three. The hope is that given some simple...

I expect that to be true, only you need to move beyond LQG by including framed ribbons for eg.

I don't have a complete grasp on the physical picture Wen is proposing, but I would guess that is what should happen in the limit that \Lambda \rightarrow 0 , i.e. as SU(2)_k \rightarrow SU(2)

1. The grid or graph or whatever you wish to call the "exoskeleton" of spacetime, is definitely not regular. Of course, to be precise you have to define what you mean by "regular" etc. etc. I'll assume you're talking about the regularity of a cubic or square lattice. The problem with such graphs...