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Bayero Journal of Pure and Applied , 1(1):108 – 111 Received: December, 2008 Accepted: December, 2008

NUMERICAL CALCULATIONS IN THE GENERAL DYNAMICAL THEORY OF GRAVITIONAL DIALATION

*1Mai- Unguwa, H. and 2Owoneku, Z. 1Department of Physics, Bayero University, P.M.B. 3011, Kano 2Department of Physics Jigawa State College of Education, Gumel *Correspondence Author

ABSTRACT It is well known that, Einsten’s Geometrical Principles and Laws of Gravitation may be used to construct a corresponding theory of Gravitational . In (Howusu, 1991) paper, it was shown how to extend Newton’s Dynamical Principles and Laws based upon the experimental facts of inertia, active and passive available today. In this paper, we apply this extended Dynamical Principles and Laws and compare to construct a corresponding theory of Gravitational Time Dilation and compute the ratio of the to for both general and dynamical theory of gravitation.

Key words: Dynamic, Gravitational Time Dilation, Einstein, Numerical, Theory

INTRODUCTION well known, its instantaneous T is given In the paper (Howusu 1991) entitled, “On Gravitation by of Moving Bodies”, the following postulates were Thv= (1) introduced:- where is a quantity and vanishes when the photon The Instantaneous inertial mi and passive and is at rest. Also by definition and postulate in section mass mp and active mass mA of a photon of frequency ν is given by (1) the instantaneous gravitational potential energy vg of photon is given by hv (2) mmmAr===1 It therefore follows by definition that the c2 instantaneous mechanical energy E of the photon is In all inertial frames and proper , where c is the given by of light in vacuum and h is plank’s constant. This postulate was based upon the ⎡ 1 ⎤ experimental physical facts available today, such as Ehv= ⎢1+Φg ⎥ (3) phenomena of Compton Scattering (Roser 1954; ⎣⎢ c2 ⎦⎥ Hoffman 1989) and radiation pressure (Jackson 1975; Therefore, it follows from the principle of Joos 1950). Conservation of mechanical Energy in gravitational This forms the basis of the General fields that the instantaneous frequency of the photon Dynamical Theory of Gravitation for photons. It was is given by shown immediately how the general dynamical theory −1 of gravitation resolves the phenomena of (i) ⎧⎫11⎪⎪⎧⎫ gravitational spectral shift and (ii) gravitational υυ[]rt1,=+Φ⎨⎬⎨⎬11goo⎡ rt⎤⎡⎤ +Φgrt[], r , t c2 ⎣ ⎦⎣⎦ deflection (lensing) (Howusu, 1991) in solar system in ⎩⎭⎩⎭⎪⎪c2 excellent agreement with experiment, (Howusu 1991; Reasenberg 1976; Richard 1975; Eddington 1923). Now in this papar we construct the general dynamical where is the frequency at the particular position r law of gravitational time dilation for comparison with o at time t . This is the General Dynamical Law of experimental measurements. o Gravitational Spectral Shift for photons, (Howusu,

2001).

Now it is well known that the frequency of a is MATERIALS AND METHODS directly proportional to its successive ticks. It Calculations therefore follows from the General Dynamical Law of Consider a photon with instantaneous frequency in Gravitational Spectral Shift that the coordinate time a gravitational field of potential . Then as is (t) measured by the photon and all other in a gravitational field satisfied the relation,

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−1 ⎪⎪⎪⎪⎧⎫⎧⎫11 dt() r=+Φ⎨⎬⎨⎬ 1ggoo () r 1 +Φ () r dt ( r ) (5) ⎩⎭⎩⎭⎪⎪⎪⎪cc22 This is the General Dynamical Law of Gravitational It may be noted that for a clock located in the Time Dilation (Aatwater, 1974). gravitational field of stationary homogenous spherical body of radius r and rest mass Mo GM Φ=()rro ; > R o r Consequently the General Dynamical Law of Gravitational Time Dilation, equation (5), become:- −1 ⎡⎤GM⎡⎤ GM

dt() r=−⎢⎥ 12 1 − dtoo ( r ) (7) ⎢⎥c2 ⎣⎦cro ⎣⎦r and choosing the particular point at infinite distance from the body: r = ∞ (8) This time is the proper time; t (9) Thus (7) become −1 ⎡⎤GM dt (r) = ⎢⎥1− dr (10) ⎣⎦⎢⎥cr2 This is the relation between coordinate and proper field of a stationary homogenous spherical body such time in the gravitational field exterior to a stationary as the sun in (7) and (10). homogenous spherical body according to the General It may be noted that the expression for Dynamical Law of Gravitational Time Dilation. It is Einstein’s graviotational time violation in the field of a now obvious from the relation to the proper clock. stationary homogenous body according to the geometrical theory of general relatively is given by RESULTS AND DISCUSSION (Atwater, 1974; Foster, 1979), In this paper we derived the general dynamical law of gravitational time dilation (5) and specialized it to the

(11)

Hence to the order of c-2, the general dynamical law It may be immediately seen that, within the of gravitational time dilation is identically equivalent to General Dynamical Theory of Gravitation the Einstein’s expression in . phenomenon of Gravitational Time Dilation is a Consequently, to the order of c-2, the general consequence of the electrical mean field. Therefore, dynamical theory of gravitation resolves the within the General Dynamical Theory of Gravitation phenomenon of gravitational time dilation as the phenomenon of Gravitational Time Dilation excellently as Einstein’s theory of general relativity becomes understandable in the most natural and (*GR). physical way that if the total mechanical energy of the This agreement between the gravitational clock remains constant and the Gravitational Potential time dilation according to Einstein’s general relativity Energy changes then the state of motion of the clock and the general dynamical theory in this paper is must change accordingly. And this can be seen and illustrated in Table 1. appreciated in the cases of all real such as It may be noted further that to order finer c- 2 the mechanical and pendulum and atomic clocks. Now the expression for the gravitational time dilation of a clock dynamical concept of Gravitational Time Dilation may in the field of a Centro symmetric spherical massive be compared with the corresponding Einstein theory body due to the general dynamical theory of to which Gravitational Time Dilation is due to the so- gravitation in this paper is different for the called “curvature” or “bending” of – time corresponding Einstein’s expression due to his around a massive body. it is also most interesting and geometrical theory of classical gravitation (GR). This instructive to note immediately the great difference is most welcome as a means of mathematical simplicity of the Dynamical Theory of distinguishing ultimately between the general classical gravitation in this paper which is formulated dynamical theory of gravitation and Einstein’s in terms of the natural three- dimensional space geometrical theory of gravitation, as the accuracy of vectors and proper times. experimental measurement increases in the .

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Table1: calculated values of the ratio of coordinate time to proper time for both general relativity and dynamical theory of gravitation.

Body Mass (M) Kg Orbital Radius ® M General Relativity Dynamical Theory of Gravitation 1 1 − − ⎡⎤dT⎡⎤2 GM 2 ⎡⎤dT⎡⎤2 GM 2 −11=−⎢⎥ 1 −11=−⎢⎥ 1 ⎢⎥dt ⎢⎥dt ⎣⎦⎣⎦⎢⎥cR2 ⎣⎦⎣⎦⎢⎥cR2

Sun 1.960 x 1030 6.96 x 108 2.105 x 10-6 2.105 x 2710-6 Mercury 3.360 x 1020 5.79 x 1010 4.300 x 10-15 4.305 x 10-15 Venus 4.920 x 1024 1.08 x 1011 3.376 x 10-14 3.376 x 10-14 6.000 x 1024 1.49 x 1011 2.984 x 10-14 2.984 x 10-14 Mars 6.600 x 1023 2.28 x 1011 2.145 x 10-15 2.145 x 10-15 Jupiter 1.920 x 1027 7.78 x 1011 1.829 x 10-12 1.829 x 10-12 Saturn 5.700 x 1026 1.43 x 1012 2.954 x 10-13 2.954 x 10-13 Uranus 9.000 x 1025 2.87 x 1012 2.324 x 10-14 2.324 x 10-14 Neptune 1.020 x 1026 4.50 x 1012 1.680 x 10-14 1.680 x 10-14 Pluto 4.800 x 1024 4.80 x 1012 6.050 x 10-16 6.050 x 10-16

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This simplicity may be compared with the Howusu, S.X.K. (1991). : On the Gravitation of Moving mathematically more rigorous formulation [Phipps Bodies.” Phys. Essays 4(1), 81 – 93. 1926] of Einstein’s Geometrical Theory of Gravitation Howusu, S.X.K. (2001); the natural philosophy of (GR) in terms of tensors of several ranks and types in gravitation. University of Jos press, Jos the abstract four-dimensional space – time. Nigeria. Jackson, J.D. (1973): Classical Electrodynamic. CONCLUSION (J.Wiley, New York), PP. 265. It is obvious that to the order of c-2, the general Joos J.G., Freeman, I.M. (1950); Theoretical Physics theory of dynamical gravitation is in perfect (Hafiner, New York ), pp.678 -706. agreement with the Einstein’s general relativity theory Reasenberg, R.O. et al (1976): “ Solar System Tests of Gravitation. General Relativity”, in preceeding of the international Symposium on Experimental REFERENCES Gravitation. Pivia 1976, edited by Bertotti, B. Atwater, H.A. (1974). “Introduction to General (Academic National del Lincei, AM. J. Phys. Relativity (Pergamon, New York), pp. 99 – 54(3), 245 – 247. 104. Richard, J.P.(1975): “Tests of Theories of Gravity I Eddington, A.S. (1923). “The Mathematical Theory of the Solar Systems”, in General Relativity and Relativity” (Cambridge, London), pp. 40 – Gravitation, edited by G. Staviv and J.Ross 41. (Wiley, New York), pp. 169 – 188. Foster , J., Nightingale, J.D. (1979). A shout Course in Rosser, W.G.V. (1964): An introduction to the Theory General Relativity) (Longman, New York), of Relaivity. (Butterworth, London), pp. 174 pp. 92 – 130. – 247. Hoffman, M.F.J. (1989).” The Compton Effects as an Experimental Approach

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