[HN Gopher] Reforming the Mathematical Language of Physics (2002...
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       Reforming the Mathematical Language of Physics (2002) [pdf]
        
       Author : alokrai
       Score  : 57 points
       Date   : 2021-02-14 21:39 UTC (2 days ago)
        
 (HTM) web link (worrydream.com)
 (TXT) w3m dump (worrydream.com)
        
       | ktpsns wrote:
       | I think the author proposes geometric algebra for widespread use
       | in teaching fundamental physics. That's a good idea, it unifies a
       | lot of things and brings new insights! Hestens seems to be quite
       | popular with his opinion, see for instance
       | https://link.springer.com/chapter/10.1007/978-94-011-5036-1_...
       | and https://en.wikipedia.org/wiki/Geometric_algebra
       | 
       | Very interesting! But it requires really a skilled lecturer to
       | make students understand the concepts. I've heard advanced
       | mathematical physics by a, well, bad lecturer, who taught
       | everything on some abstract level which I never heard from
       | previously (and after). I had to learn differential geometry and
       | all that later on my own in order to graduate in some topic in
       | general relativity.
        
       | abelaer wrote:
       | (Disclaimer: haven't read the whole thing) This just seems like
       | one of these situations: https://xkcd.com/927/
       | 
       | The fact that the same physical system can be described by very
       | different kinds of mathematics is often very illuminating and
       | interesting, rather than confusing. It's one of the reasons that
       | physics can inspire mathematics, rather than maths just being a
       | tool that physicists use. Different types of mathematics often
       | allow you to emphasise different properties of the same system,
       | so being comfortable in more than one language brings you freedom
       | and new insights.
        
         | zentiggr wrote:
         | I've never had a chance to dive deeply into most 'advanced'
         | math topics, but I've readd more than one of Hestenes's papers
         | (and cohorts) and honestly GA looks to be so much clearer,
         | concise, and more easily worked than having to blend together
         | vectors, matrixes, and other constructs in order to do the same
         | work in more complicated ways, with extra notational layers.
         | 
         | Again, I don't use any of this in real life, so YMMV, but it
         | looks very clean, fast, and intuitive compared to (waves at
         | everything else).
        
       | Ceezy wrote:
       | There is some very good propositions in this paper. Physics
       | should definitively have less redundant mathematics formulations
       | of problems. Hamiltonian physics is quite close to Newtonian in
       | comparison quantum physics.
        
       | jojobas wrote:
       | First I thought it would be about dumbing down the existing maths
       | so more people can understand.
       | 
       | Some 10 pages in I realized it's explaining the concepts I've
       | internalized years ago in a way I can't comprehend at all.
        
       | mncharity wrote:
       | Hestenes; The Genesis of Geometric Algebra: A Personal
       | Retrospective (2017)[1]
       | 
       | [1]
       | https://link.springer.com/content/pdf/10.1007/s00006-016-066...
        
       | carapace wrote:
       | Hestenes on Victor's radar, that seems promising! :)
       | 
       | I like to mention on such threads:
       | 
       | "Geometric Algebra for Electrical and Electronic Engineers"
       | 
       | > In this paper, we explicate the suggested benefits of
       | Clifford's geometric algebra (GA) when applied to the field of
       | electrical engineering. Engineers are always interested in
       | keeping formulas as simple or compact as possible, and we
       | illustrate that geometric algebra does provide such a simplified
       | representation in many cases. We also demonstrate an additional
       | structural check provided by GA for formulas in addition to the
       | usual checking of physical dimensions. Naturally, there is an
       | initial learning curve when applying a new method, but it appears
       | to be worth the effort, as we show significantly simplified
       | formulas, greater intuition, and improved problem solving in many
       | cases.
       | 
       | https://ieeexplore.ieee.org/document/6876131
        
       | yesenadam wrote:
       | I recently read John Vince's _Geometric Algebra for Computer
       | Graphics_ , which seemed excellent - written, the author
       | explains, because he realized you had to virtually be a
       | mathematician to understand the books in the field, and he wanted
       | to write something much more accessible. It sounded great until
       | Chapter 11, _Conformal Geometry_..                 Various
       | arguments have been proposed for adopting this model such as,
       | conformal space:       * is homogeneous and consequently removes
       | the origin as being a special point       * supports points and
       | lines at infinity       * provides a single geometric mechanism
       | for representing lines, circles, planes and spheres, which
       | introduces a rare quality of elegance to problem solving       *
       | enjoys all the normal features of Euclidean space.       A model
       | of space that possesses such a range of positive features sounds
       | too good to be true! But remember, in mathematics there is no
       | such thing as a free lunch. So what price must we pay for this
       | model?
       | 
       | Then Vince explains that the conformal model, "an alternative
       | space to Euclidean space for solving 3D geometric problems", is
       | covered by a patent..of Hestenes, _US Patent 6,853,964 System for
       | encoding and manipulating models of objects_. Vince says
       | "Licences to employ this system for commercial purposes are
       | available through the patent holders, although there are no
       | restrictions for academic research and educational use. All of
       | the above may be a small price to pay for the benefits associated
       | with the conformal model, and I will do my best to explain the
       | model in this chapter."
       | 
       | Uh what?! So it actually costs money to use... That rather put me
       | off Hestenes' noble mission. It seems...bizarre that what seems a
       | whole subfield of mathematics is patented, rather different to
       | patenting a particular algorithm or technique. Very strange,
       | after reading so much of Hestenes' wondering why the superior GA
       | isn't used everywhere. (Is it to make the world a better
       | place..or to make Hestenes rich?..) I stopped reading at that
       | point.
       | 
       | As far as using Geometric Algebra in a Euclidean setting goes,
       | most of my programming is in 2D, but when I do 3D next I will
       | consider using it, it seems very cool. Most of the
       | features/differences/advantages over the usual vector/matrix
       | geometry only appear in 3 or more dimensions. Vince's book is
       | great at explaining it, highly recommended.
        
         | gg80 wrote:
         | It seems the patent has been discontinued:
         | https://patents.google.com/patent/US6853964B1/en
        
           | yesenadam wrote:
           | Oh thank you. Hmm "Status Expired - Fee Related .. 2022-07-13
           | Adjusted expiration" .. is that like when your power gets cut
           | off from not paying the bill? p.s. Vince's book was published
           | in 2008.
        
         | benrbray wrote:
         | Is this... legal? How on earth was a patent like that approved,
         | and surely it wouldn't hold up to scrutiny, right?
        
           | dmitrybrant wrote:
           | Most people familiar with the US patent office will agree
           | that it's totally broken. The reviewers are not scientists,
           | and aren't required to understand what's being proposed in a
           | patent. They simply perform a search for prior art.
           | 
           | As a result, all kinds of pseudoscience has gotten
           | "patented", for example this patent for detecting
           | "tachyonized" materials (you know, materials that have been
           | infused with tachyons, the hypothetical particles that travel
           | faster than light):
           | 
           | https://patents.google.com/patent/US7760357B2/en
        
           | jcranmer wrote:
           | It looks like the patent was approved in between the CAFC
           | decision of State St. (subject matter is patentable if it
           | produces a "useful, concrete, and tangible result") and
           | SCOTUS's Bilski decision (State St. is on crack and not good
           | case law). Bilski and later Alice have made it rather clear
           | that these kinds of abstract patents aren't going to fly, not
           | that it stops patent attorneys from pretending otherwise.
           | 
           | So this patent very likely wouldn't hold up in court. It was
           | approved in a time when the USPTO more or less gave up on
           | adjudicating patentability (thanks to the State St.
           | decision).
        
       | WildParser wrote:
       | Good that people sometimes remember that a more modern base for
       | physics would be nice.
       | 
       | Doing electrodynamics without using alternating products and
       | differential forms feels so wrong...
        
       | wolfram74 wrote:
       | This line on page 6 confuses me a bit --For example, for
       | applications to rotations, quaternions are demonstrably more
       | efficient than the vectorial and matrix methods taught in
       | standard physics courses
       | 
       | And then claims that aerospace engineers mostly use quaternions.
       | It's from 2002, so it's sense of what's in vogue might be dated,
       | but I'd understood at least in the graphics manipulation world,
       | the vector/matrix methods were dominant. Those are separate
       | industries, so both statements could be true, anybody have
       | opinions?
        
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