Papers by Gordon Liu
Physicists have employed various approaches to solve the “paradox” and offered a consistent concl... more Physicists have employed various approaches to solve the “paradox” and offered a consistent conclusion that the traveller twin is younger than the homebody twin. However, some authors attribute the cause of differential aging to acceleration, while others believe that acceleration should not be regarded as the source of differential aging, but frame switch is. So far there is no agreement on this issue. Actually, acceleration and frame switch should not be regarded as the source of differential aging. The author will introduce a thought experiment in which two very long spacecraft are moving in opposite directions at a speed close to the speed of light to discuss the real cause of differential aging. The author found that the real cause of differential aging in the twin “paradox” is because of the asymmetry of destination choice. People always choose their destinations in the universe rather than in spacecraft. The destinations are always stationary relative to the homebody twin and...
Although mass is a very common and fundamental concept, but the problem of mass is still one of t... more Although mass is a very common and fundamental concept, but the problem of mass is still one of the key problems of modern Physics, up to the present the experts are not able to reach a consensus. In this paper, we have discussed the problems relating to mass, energy and matter, and been aware that mass is neither the amount of matter an object has, nor the measure of inertia and the source of gravitational field, whereas energy is the measure of the inertia of an object and also is the source of gravitational field. As before, Mass being used to measure the inertia and to calculate gravitational force is just an approximate method only for very slowly moving bodies and particles for which the rest energy is much larger than the kinetic energy. Actually the concept of mass is a superfluous artificial concept, just rest energy divided by a constant 2 c (If selecting , the mass is exactly equal to the rest energy), does not have any other meaning. If the concept of mass is completely superseded by energy(or more precisely, rest energy), the physical equations are completely perfect, their meanings are clearer, and the puzzles such as the relationship of mass and energy, nature of matter, the essence of the weak equivalence principle, the physical meaning of Higgs mechanism, etc., can be made clearer.
In present paper, we have proposed an alternative theory on the spacetime of non-inertial referen... more In present paper, we have proposed an alternative theory on the spacetime of non-inertial reference frame (NRF) which bases on the requirement of general completeness (RGC) and the principle of equality of all reference frames (PERF). The RGC is that the physical equations used to describe the dynamics of matter and/or fields should include the descriptions that not only the matter and/or fields are at rest, but also they move relative to this reference frame, and the structure of the spacetime of reference frame has been considered. The PERF is that any reference frame can be used to describe the motion of matter and/or fields. The spacetime of NRF is inhomogeneous and deformed caused by the accelerating motion of the reference frame. The inertial force is the manifestation of deformed spacetime. The Riemann curvature tensor of the spacetime of NRF equals zero, but the Riemann-Christoffel symbol never vanishs no matter what coordinate system is selected in the NRF. The physical equations satisfied the RGC remain covariance under the coordinate transformation between the reference frames. Mach's principle is incorrect. The problem of spacetime of NRF can be solved without considering gravitation.
The success of Special Relativity (SR) comes from the requirement of Lorentz covariance to all ph... more The success of Special Relativity (SR) comes from the requirement of Lorentz covariance to all physical equations. The explanation with regard to the Lorentz covariance is based on two hypotheses, namely the principle of special relativity and the constancy of the speed of light. However, the statements of the principle of special relativity are various and confusing. The covariance of physical equations and the equality of inertial frames of reference are mixed up. The equality of inertial frames of reference is obvious, but the covariance of the physical equations is a more advanced requirement. Additionally, the way that the propagation property of light is placed in a central position of SR has caused people misunderstandings towards space-time, and also there is a logical circularity between the measurement of speed of light and the synchronization of clocks. These have obstructed to correctly extend the theory of space-time from an inertial frame of reference to a non-inertial frame of reference. These are the main reasons why many people criticize SR. In present paper, the two hypotheses have been discussed in detail and a new requirement to the equations of Physics has been proposed. The requirement is the Requirement of Special Completeness, namely, the physical equations used to describe the dynamics of matter and/or fields should include the descriptions that not only the matter and/or fields are at rest relative to an inertial frame of reference, but also they move relative to this frame. Basing on this requirement and the equality of the inertial frames of reference, we can approach to SR. Thereby let the theory of Lorentz covariance has a clear and solid foundation. The constancy of the speed of light is just a deduction, not a premise. The Lorentz covariance is just a characteristic of the Special Complete equations. Maxwell equations automatically satisfy the Lorentz transformations without any modification, while Newton law of gravity does not, because Newton law of gravity is not Special Complete and Maxwell equations are. The new approach has paved a road leading towards the generalizing of the theory of space-time from the inertial frame of reference to non-inertial frame of reference without considering gravitation. Résumé: Le succès de la relativité restreinte (RR) provient de l'exigence de la covariance de Lorentz à toutes les équations physiques. L'explication en ce qui concerne la covariance de Lorentz est fondée sur deux hypothèses, à saa
Let the coordinate system i x of flat space-time to absorb a second rank tensor field ij of the... more Let the coordinate system i x of flat space-time to absorb a second rank tensor field ij of the flat space-time deforming into a Riemannian space-time, namely, the tensor field is regarded as a metric tensor with respect to the coordinate system x . After done this,
Conference Presentations by Gordon Liu
Uploads
Papers by Gordon Liu
Conference Presentations by Gordon Liu