Annalen der Physik. 7. Folge, Band 47, Heft 6, 1990, S. 605-506 J. A. Barth, Leipzig Comment on "Sketch of a New 5-dimensional Projective Unified Field Theory" By Josh A. FERRARI Institut fur Theoretische Physik, Technische Universitlit Berlin (West) Kommentar zu ,,Skizze einer neuen 5-dimensionalen Projektiven Einheitlichen Feldthe~rie'~ E. Schmutzer has recently published a new version of a 5-dimensional Projective Unified Field Theory unifying gravitation, electromagnetism and a new interaction called scalarism [ l]. I n this theory a qualitatively new physical quantity (scalaric substrate density) occurs as a source term for scalarism. Since this quantity stems from the nongeometrized matter (substrate),i t must be handled as an ansatz (i.e., the source term for scalarism cannot be deduced from the geometrized theory). I n [ l ] the author make the tentative hypothesis that leptons (c.g. electrons and positrons) could possess the scalarism inducing property. I n the quasi-Newtonian approximation, the equation of motion of a test-body with "scalaric body parameter" Tois given by (eq. (go), [l]) + i = -(I I'0j70/3) grad @ , (1) where @ is the Newtonian potential and yo is the scalaric substrate parameter of the sources of the external fields. To is defined by (eq. (94), [l]) here mOeand mOlzare taken as the electron rest inass and the nucleon rest mass, respectively; N a is the number of atoms of sort 52 in the sources of the external fields; Za is the atomic number (i.e., electrons per atom) and An is the number of nucleon per atom of sort 52. Tois given by an equation similar to eq. 2 (see eqs. (85)-(89), [l]). Eq. (1) predicts a composition-dependent gravitational-to-inertial mass ratio for the test-body given by mclmr = 1 i-Fobyo/3 (i.e., it depends on the composition of the test-body itself and on the composition of the source). We will here point out that this composition-dependent ratio contradicts the experimental results of Dicke et al. , and Braginskii et al. ; these are the main experiments on the validity of the principle of eqiiivalence. 506 Ann. Physik Leipzig 47 (1990) 6 Dicke et al. investigated the difference of gravitational-to-inertial mass ratios for Aluminium (Al) and Gold (Au) in the field of the Sun. They found j (mG/ml)al - ( ~ G / m l ) A uI < 3 x (3) Braginskii and Panov compared Aluminium and Platinum (Pt) also in the field of the Sun, and found I (mO/ml)*l - (mc/mr)rt j < 0.9 x (4) To compare the above mentioned composition-dependent ratio with Dicke’s and Braginskii’s results, we have to calculate I‘, for Al, Au arid Pt, and a lower limit for To. Since (ZR/An)2 1/3 holds for all elements, from eq. (2) we get For the scalaric body parameter r, I‘,,we have (eq. (89), ) 5.45 x 10-4 Z/A, hence, we obtain 2.62 x ( Z / A M 0.48), ( Z / A = 0.40), I‘(;pt) M 2.18 x (see footnote l)). Then, the difference of gravitational-to-inertial mass ratio for A1 and Au is M M 2.18~ (7) (8) (9) and for A1 and Pt, we also have I (mG/mI)Al - (mG/mI)Pt I I~o(AI) 1 - r o ( p t ) 7 0 / 3 > 2.6 X lop9. (11) Thus, we have a contradiction with the experimental results shown in (3) and (4). References [l] SCHMUTZER, E.: Ann. Physik (Leipzig) 45 (1988) 678. R. ; DIUKE, R. H. : Ann. of Physics 26 (1964) 442.  ROLL,P. G.; KROTKOV,  BRAGINSKII, V. B.; PANOV, V. I.: Zh. Eksp. Teor. Fiz. 61 (1971) 873 /Sov. Phys. JETP 34 (1972) 4631. Bei der ltedaktion eingegangen am 24. Juli 1989. Anschr. d. Verf.: Dr. J. A. FERRARI Institut fur Theoretische Physik Technische Universitat Berlin Hardenbergstr. 36 D-1000 Berlin (West) 12 I) In the computation of To for Pt we must use the more general formula given in eq. (85), [l], which is similar to eq. (2); that is, we must “average” over the natural isotopes of Pt, and weight its contributions according to its relative frequency in the nature. In this case R 2 NnAn R M 0.40.