> On 12 Jan 2019, at 23:17, Brent Meeker <[email protected]> wrote: > > > > On 1/12/2019 2:51 AM, Philip Thrift wrote: >> >> >> On Friday, January 11, 2019 at 7:19:06 PM UTC-6, Brent wrote: >> >> >> On 1/11/2019 1:57 PM, Philip Thrift wrote: >>> >>> >>> On Friday, January 11, 2019 at 2:46:35 PM UTC-6, Brent wrote: >>> >>> >>> On 1/11/2019 6:01 AM, John Clark wrote: >>>> On Thu, Jan 10, 2019 at 8:18 PM Brent Meeker <[email protected] <>> >>>> wrote: >>>> >>>> > The fine structure constant is e^2/hbar*c. Those three values are >>>> > measured independent of any Feynman diagrams >>>> >>>> Absolutely correct. So if you use Feynman diagrams to predict what some >>>> physical system is going to do, such as a physical system of 2 electrons >>>> being hit by a photon of light with a wavelength small enough to contain >>>> enough energy to prevent the electrons repulsion, then you'd better get a >>>> number very close to the Fine Structure Constant. If you don't then >>>> Feynman Diagrams aren't any good. >>>> >>>> They didn't use 12,672 Feynman Diagrams because they wanted to know what >>>> the Fine Structure Constant was, they already knew what that number was to >>>> many decimal places from exparament, they used 12,672 Feynman Diagrams >>>> because they wanted to see if Feynman Diagrams worked. And it turned out >>>> they worked spectacularly well in that situation, and that gives >>>> scientists great confidence they can use Feynman Diagrams in other >>>> situations to calculate what other physical systems will do that involve >>>> the Electromagnetic Force. >>> >>> There's always an interplay between theory and experiment. It's completely >>> analogous to Maxwell's discovery that light is EM waves. There were already >>> experimental values of the permittivity and permeability of the vacuum and >>> there were values for the speed of light. Maxwell showed that his theory >>> of EM predicted waves and using the permittivity and permeability values >>> the speed of the waves matched that of light. Now the speed of light is a >>> defined constant and so are the permittivity and permeability of the >>> vacuum. So the connecting of the three values by a theory allows their >>> values to be defined. In the case of the anomalous magnetic moment of the >>> electron, hbar and c are already defined constants. So quantum field >>> theory (for which Feynman diagrams are just a calculational tool) linked >>> them and e to g. >>> >>> Brent >>> >>> >>> >>> >>> If Feynman Diagrams (tools) are sufficient (to match experimental data) >>> then Quantum Field Theory can be thrown in the wastebasket. >> >> ?? Feynman Diagrams are just a mathematical trick for summing up terms to >> approximate the propagator of QFT. >> >> Brent >> >> >> You just make Feynman Diagrams the fundamental elements of the theory, and >> propagators derived from them. > > How many diagrams? The propagator has a clear interpretation as connecting > the field at x with the field at y. Feynman showed that his diagrams > provided a good mnemonic for the infinite number of terms that would sum to > the propagator. If you take the diagrams as fundamental you then need to > specify how many. > >> >> Just like histories are made fundamental, and Hilbert Spaces are derived >> from them. > > Hilbert spaces are infinite dimensional vector spaces. So you have the same > problem: How many histories?
The aleph_1 one on which your consciousness can differentiate, but in practice we can use only the aleph_0 local pieces of histories (which are indexical sets of past/memories+future/accessible-worlds). Bruno > > Brent > >> >> https://arxiv.org/abs/1002.0589 >> <https://arxiv.org/abs/1002.0589> >> >> Theories do not come from Mount Olympus. >> >> - pt >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] >> <mailto:[email protected]>. >> To post to this group, send email to [email protected] >> <mailto:[email protected]>. >> Visit this group at https://groups.google.com/group/everything-list >> <https://groups.google.com/group/everything-list>. >> For more options, visit https://groups.google.com/d/optout >> <https://groups.google.com/d/optout>. > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
