An Extended Abstract Theory of special and general relativity (SR and GR, respectively), received so much popularity and attention from the scientific media that a lot of papers in modern physics are devoted to it. One of the main constituents in the special relativity is a very known Lorentz Transformations (LT). There are many derivations of Lorentz Transformations (1-5). In all of the known derivations methods of the Lorentz Transformation model (LT-model), it is assumed that the observation signal is the light, which has the same (constant) speed in both observer and moving systems. So, one of the remaining questions is: are there possibilities to generalize LT-model in the sense of employing of a set of different observation signals including the light signal? It is expected that this generalization should contain both Lorentz-Einstein and Galilean Transformations, and could be helpful in a new unification of electromagnetic and gravitational fields. This paragraph was the basic motivation why this investigation started with a new general approach to derivation of Lorentz Transformations. This has been resulted with a new General Lorentz Transformation model (GLT-model), proposed in this paper. In Galilean space-time model the physical existence of an absolute time is assumed. The pioneer of physics Isaac Newton defined it in the reference (6). On the contrary, Minkowski space-time model does not know any absolute time which is physically meaningful. It was the revolutionary idea of Albert Einstein to give the notion of simultaneity a new definition. Especially, because all experimental tests to determine the motion with respect to some absolute space-time frame had failed, Einstein decided to abandon the notion of absolute time at all. It implies, in contrast to Galilean space-time model, that simultaneity is not an absolute physical quality, but a relative one, depending on the motion of the observer ( i.e. the reference frame). The applications of original Lorentz-Einstein Transformations properly expresses the apparent contraction of moving rods (Lorentz-Fitzgerald contraction) and the slowing of moving clocks (time dilation). This paragraph was the grate motivation for a second part of our investigation, where we consider the influences of GLT-model on the phenomena as a moving rods contraction (a length contraction), and a time dilation, as well as on an absolute time, and a relativistic time. Applying GLT-model, in this paper, the four new observation phenomena, called a length neutrality, a time neutrality, a length dilation and a time contraction have been discovered and considered. Contemporary physics states that no object should be travel faster than the speed of light. Although the speed of light appears to be enormous when compared with conventional travelling speeds, it suggests a limit which renders a practical realization of interstellar travel improbable. Whereas Galilean space-time model allows an observation of faster than light speeds, at least in principle, Minkowski space-time model does not. What is the reason for this difference ? In the reference (7), Schatzer exposed that the key point is the conception of global time, i.e. the physical significance of the term simultaneity. Although the one-way speed of light maybe is not constant in general (i.e. when expressed in an arbitrary reference frame), the mean-speed of light c of a round-trip is again constant (8,9). This is in accordance with all experiments, like Michelson-Morley experiment. It should be emphasized that there has been no experiment which determined the one-way speed of light (10), since this would require the possibility of synchronizing physical clocks by some other means than finite-speed signals. Thus, in fact, a certain experimental proof of the constancy of the one-way speed of light has not been given so far. This paragraph states the motivation for the third part of our investigation. In this part we consider the influences of GLT-model to limitations of the particle velocities, in relation to the possibility of observation of faster than light speeds, as well as the possibility of reduction of travel times. The success of the theory of relativity can be understood from the fact that the possibility to formulate all physical laws covariantly, appears most tempting (10, 11). However, there exists no covariant representation of the state reduction postulate (12). One example is the violation of the Bell inequalities (13), which has been confirmed experimentally (14, 15). Thus, quantum mechanics has proven to be correct (16). Although non-local effects are a constituent of quantum mechanics, most physicists still believe that faster signals than speed of light are impossible. It is because EPR-like effects (17), have not allowed to transmit information at superluminal speeds so far. Yet, EPR-correlations remain a mystery if local realism is assumed to be valid. Therefore, the possibility of superluminal communication has been acknowledged by various authors (18). In the reference (19) Cramer pointed out a quantum nonlocality and the possibility of superluminal effects, within a transactional interpretation of quantum mechanics and a non-linear quantum mechanics ( Weinberg, (20) ). Two years after Weinberg 's non-linear quantum mechanics was published, Polchinski presented that Weinberg' s non-linear corrections upset the balance in quantum mechanics that prevents superluminal communication using EPR experiments (21). Meanwhile, several tests indicated that any non-linearities in the quantum mechanics are extremely small, if they exist at all. Besides, it is well known that one can define a universal time, which appears in cosmological models as the cosmological time (22). Therefore, there exists no covariant 4-position operator in quantum mechanics. Since GLT-model contains both Lorentz-Einstein and Galilean space-time models (it means relativistic and absolute time approaches) this paragraph motivates for consideration of possibilities of an unification of the general relativity and the quantum mechanics approaches applying GLT-model. If it is possible at all, the first step must be a new unification of electromagnetic and gravitational fields. The preliminary investigation results indicate that GLT-model can help in this unification. Resent investigations of electromagnetic radiation propagating over cosmological distances seem to reveal a true anisotropy in the structure of our universe. It suggests that the speed of light might be not a true constant, but dependent on direction and polarization. These results might possibly represent a further indication in favour of the existence of an absolute reference frame (23). In the reference (24) Alcubierre presented that even within the frame work of general relativity faster than light speed is allowed, provided that the space-time metric of the universe is globally hyperbolic, and assuming that an exotic matter exists. The last two paragraphs suggest considerations of the possible ways (methods) for dynamic control of gravity or inertia in order to travel by faster than light speed, or at least close to this speed. This is the fourth objective of our investigation in this paper. As it is well known (25, 26) ideal interstellar drive would have ability to manipulate the connection between mass and space-time. One approach is to analyse the possibility of using of electromagnetism. It is known that electromagnetism and gravity are coupled phenomena, and we only need to recognize how to control inertial or gravitational forces. Although gravity's affects on electromagnetism have been confirmed (27, 28) , the possibility of using electromagnetism to affect gravity is unknown. Meanwhile, the resent investigations (29, 30) suggest that inertia is nothing but an electromagnetic illusion, and that gravity is nothing other than an electromagnetic side-effect. Following the previous paragraphs, a new general structure of Lorentz Transformations, in the form of General Lorentz Transformation model ( GLT-model ), has been derived. This structure includes both Lorentz-Einstein and Galilean Transformations as its particular ( special ) realizations. If GLT-model is correct then there are exist four new observation phenomena ( a length and time neutrality, and a length dilation and a time contraction ). Besides, the well known phenomena ( a length contraction, and a time dilation ) are also the constituents of GLT-model. It means that there is a symmetry in GLT-model, where the center of this symmetry is represented by a length and a time neutrality. An observation of the mentioned phenomena of GLT-model, in a particular case, depends on an observation signal velocity in both observer and moving systems, and on a velocity of a moving system relative to an observer system. A special consideration is devoted to a correlation between GLT-model and a limitation on particle velocities in order to investigate the possibility of a travel time reduction. The next goal is the investigation of influences of a time neutrality and a time contraction to the possibility of control of gravity or inertia. The previous investigation results give the hope that GLT-model can be helpful in investigation of the mentioned problems. We believe that for determination of influences between electromagnetism and gravity in both directions, one should make a new unification of electromagnetic and gravitational fields, using a new approach that includes properties of GLT-model. This unification should be done for multivariable gravitational field (two-body or n-body gravitational problems). Maybe this approach will help in the determination of the possibility of control of gravity or inertia. References (1) A. Einstein, " The collected papers of Albert Einstein", Vol. 2: The Swiss years: writings, 1900-1909 (Princeton, NJ, 1989. (2) A. Einstein, " The meaning of relativity " London, 1951. (3) A. I. Miller, " Albert Einstein's special theory of relativity : Emergence (1905) and early interpretation (1905-1911)", Reading, Mass., 1981. (4) I. Supek, " Theoretical physics and structure of matter", Skolska knjiga, Zagreb, (Cro), 1964, 1992. (5) M. A. Baig, " Derivation of Lorentz-Einstein Transforms and their impossibility at v!= 0", in http://www.eecs.uic.edu/nbutt/ , pp. 1-11, 1997. (6) I. Newton, " Mathematical principles of natural philosophy", Dawson, London, 1969. (7) L. Schatzer , " The speed of light - A limit on principle?", in http://monet. physik.unibas.ch/schatzer/space-time.html, pp. 1-10, October 1997. (8) J. P. Hsu, and L. Hsu, " A physical theory based solely on the first postulate of relativity", Physics Letters A 196, pp. 1-6, 1994. (9) F. Selleri, " Theories equivalent to special relativity", in Frontiers of Fundamental Physics, eds. M. Barone, and F. Selleri, Plenum Press, New York, 1994. (10) H. Reichenbach, " The philosophy of space and time", Dover, New York, 1958. (11) J. D. Jackson, " Classical electrodynamics", Wiley, New York, chapter 11, 1975. (12) Y. Aharonov, and D. Z. Albert, " Can we make sense of the measurement process in relativistic quantum mechanics ?", Physical Review D 24, pp. 359-370, 1981. (13) J. S. Bell, " On the Einstein Podolsky Rosen paradox", Physics 1, no. 3, p. 195, 1964. (14) A. Aspect et al., " Experimental realization of Einstein Podolsky Rosen Bohm gedankenexperiment : A new violation of Bell's inequalities", Physical Review Letters 49, no. 2, p. 91, 1982. (15) A. Aspect et al., " Experimental tests of Bell's inequalities using time-varying analyzers", Physical Review Letters 49, no. 25, p. 1804, 1982. (16) R. Y. Chiao, P. G. Kwiat, and A. M. Steinberg, " Faster than light ?", in Scientific American, August 1993. (17) A. Einstein, B. Podolsky, and N Rosen, " Can quantum-mechanical description of physical reality be considered complete?", Physical Review 47, p. 777, 1935. (18) O. Steinmann, " The EPR Bingo", Helv. Phys. Acta, vol. 69, pp. 702-705, 1996. (19) J. G. Cramer, " Quantum nonlocality and the possibility of superluminal effects ", in http://www.npl.washington.edu/npl/int_rep/qm_nl.html , pp 1-6, August, 1997. (20) S. Weinberg, " Non-linear QM theory ", Physical Review Letters 62, p.485, 1989. (21) J. Polchinsky , " Weinberg's non-linear corrections upset the balance in QM that prevents superluminal communication using EPR experiments ", Physical Review Letters 66, p.397, 1991. (22) S. Weinberg, " Gravitation and cosmology", Wiley, New York, chapter 14, 1972. (23) B. Nodland, and J. P. Ralston, " Indication of anisotropy in electromagnetic propagation over cosmological distances", Physical Review Letters 78, no. 16, pp. 3043-3046, 1997. (24) M. Alcubierre , " The warp drive : Hyper-fast travel within general relativity", Classical and Quantum Gravity 11, pp. L73-L77, 1994. (25) M. G. Millis, " Exploring the notion of space coupling propulsion ", in Vision 21: Space Travel for the Next Millennium, Symp. Proceedings, Apr. 1990, NASA-CP-10059, p. 307-316, 1990. (26) M. G. Millis , " Emerging possibilities for space propulsion breakthroughs " , http://www.lerc.nasa.gov/WWW/PAO/html/warp/ipspaper.htm, 1998. (27) R. Pool, " Closing in on Einstein's Special Theory of Relativity", in Science, Vol. 250, p. 1207-1208, Nov. 9, 1990. (28) C. W. Misner, K. S. Thorne, and J. A. Wheeler, " Gravitation " , W. H. Freeman and CO., New York, 1973. (29) B. Haisch, A. Rueda, and H. E. Puthoff," Inertia as a zero-point field Lorentz Force", in Physical Review A, Vol. 49, No. 2, p. 678-694, Feb. 1994. (30) H. E. Puthoff, " Gravity as a zero-point fluctuation force", in Physical Review A, Vol. 39, No. 5, (A89-33278), p. 2333-2342, Mar. 1, 1989.