Can the tensor implimentation related to covariant and contravariant co ordinate systems and moving through different co ordinate systems be helpful.I mean to say could covariant and contravariant transforms form the basis for tensor module.Thanks.
On Wed, Apr 24, 2013 at 12:17 AM, F. B. <franz.bona...@gmail.com> wrote: > Hi there! > > There are two books about applications of Geometric Algebra to > Physics (Clifford Algebra to Geometric Calculus by Hestenes and Sobczyk and > Geometric Algebra for Physicists by Doran and Lasenby). An optimal > implementation of Physics would implement a Geometric Algebraic structure > around physical quantities. > > Frankly, I think that there is a very urgent need to implement a working > tensor module enabling the usage of the Einstein summation convention. I > had a look at sympy.tensor, but it looks like that module is still far away > from working (unless I didn't figure out correctly how it works). > > Yesterday evening I wrote a draft about a FourVector object and a Dirac > Spinor object. The underlying engine is based on for-loops for the > FourVector and on matrices for the Dirac Spinor. > > I think that now it would be more appropriate to disregard Geometric > Algebra, for some reasons: > > - Geometric Algebra approach to Physics is not well known. Almost all > physics books use tensor-algebra, so one would have to waste time studying > the basics of this alternative approach to Physics. > - Geometric Algebra is fit for usage only on the areas of Physics > covered by those two books. If you would like to write code on non-standard > physics, you would have to either look for (possibly inexistent) papers or > do a research on your own on (which would be extremely difficult). > - the Geometric Algebra approach is harder and longer to implement > than the Tensor-based approach. > > I suggest the following steps to extend the physics module: > > 1. write some tensor code working with Einstein summation convention. > 2. implement objects with their transformation properties under the > Lorentz group (possibly Poincarè too). > 3. make sure that the end-user interface is different from the > internal engine using tensors. > 4. once this framework is finished, start thinking on how to convert a > tensor-based engine to a GA-based engine. > > By the way, what's the exact status of sympy.tensor? Is it going to work? > I can't wait for it to finish, I think I'll write my own temporary > workaround to start doing some physics. > > > On Tuesday, April 23, 2013 12:33:35 AM UTC+2, Aaron Meurer wrote: > >> There has been discussion on adding modules for other areas of >> physics, such as electromagnetism. I suppose the other big area that >> is missing is relativity. These all really require a graduate level of >> understanding in physics to work with, though. I'm not sure if there >> is much a first year student can do. There is some work on the units >> module at >> https://github.com/sympy/**sympy/pull/1389<https://github.com/sympy/sympy/pull/1389>that >> you can look >> at. >> >> Aaron Meurer >> >> >> On Mon, Apr 22, 2013 at 2:20 PM, Marsci <esteb...@gmail.com> wrote: >> > Hello, >> > I would really enjoy to contributing to this project, especially to the >> > physics module, unfortunately I have no idea what else I can add to the >> > physics module. It appears as all the work to be done is solely on >> quantum >> > mechanics and since I am a first year in university I do not have a >> complete >> > understanding of this field. Can someone recommend a good project where >> my >> > knowledge would be useful? >> > >> > Thanks >> > >> > -- >> > You received this message because you are subscribed to the Google >> Groups >> > "sympy" group. >> > To unsubscribe from this group and stop receiving emails from it, send >> an >> > email to sympy+un...@**googlegroups.com. >> > To post to this group, send email to sy...@googlegroups.com. >> > Visit this group at >> > http://groups.google.com/**group/sympy?hl=en-US<http://groups.google.com/group/sympy?hl=en-US>. >> >> > For more options, visit >> > https://groups.google.com/**groups/opt_out<https://groups.google.com/groups/opt_out>. >> >> > >> > >> > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sympy+unsubscr...@googlegroups.com. > To post to this group, send email to sympy@googlegroups.com. > Visit this group at http://groups.google.com/group/sympy?hl=en-US. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy?hl=en-US. For more options, visit https://groups.google.com/groups/opt_out.
