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The escape speed from one point-mass M1 is u1 = (--2U1)'=2 with U1 (= --M1G/s1) the (Newtonian) gravitational potential energy and s1 the distance between M1 and a chosen point. Observing that the escape speed, from two or more masses, increases, the total escape speed (i.e., from all the masses in universe) becomes u = (--2U)'=2, with U the total potential (energy), which is related, as shown, to the universe mass MU: According to many authors, Mu « 1053kg, and, on these bases, we found, on Earth, u ! c, so we assumed c = u. This equality implies the massiveness of the light, and because of its two related parameters, k and v, we inferred that the light has to be composed of longitudinal massive particles, photons (each one having length k), moving, along rays (succession of photons along the same direction), toward infinity with speed c (function of U), while their frequency v turns out to be their number, of the same ray, flowing in time unit. These particles, due to their speed and mass, have a momentum, and therefore, if photons and a circling electron should have, at their impact, opposite direction, the electron could fall into its nucleus; hence, the electron should have a different structure, where its charge is not uniformly distributed, whereas it can be considered as a point particle, fixed on the electron surface, facing the atom nucleus during the electron orbits, while the electron charge turns out to be the photons-electron impact point, where photons are absorbed and released. Due to this electron structure, the incident photons always force the impacting circling electron to move, with a radial velocity w (function of the incident photons frequency) toward wider orbits. On these bases, during these impacts, the electron becomes the source of re-emitted photons; hence, because of the Doppler effect involving both the incident photons and the recoiled electron, the frequency of the re-emitted photons decreases, while their length (due to the electron radial velocity w lasting as long as the interaction time T) increases by the value wT, inducing the invariance of the speed of light, despite any relative motion observer-source; we also found this invariance (which regards the interaction light-matter only) through the conservation of energy of the incident photons. Regarding the claimed time dilation, which occurs between two atomic clocks (ACs) at different potential U (e.g., at different altitude on Earth), it is shown that any variation DU implies a variation Dc, and, contemporarily, since the ACs are sources of photons at a given frequency on Earth, DU gives a variation of the ACs frequency Dv, hence of their ticking time T = 1/v, and therefore a variation of their counted time. Finally, the equality c = u implies a cosmological reason regarding an endless balance between collapse and dispersion of the universe masses. [ABSTRACT FROM AUTHOR]

It is well known that simultaneity within an inertial frame is defined in relativity theory by a convention or definition. This definition leads to different simultaneities across inertial frames and the well-known principle of relativity of simultaneity. The lack of a universal present implies the existence of past, present, and future as a collection of events on a four-dimensional manifold or continuum wherein three dimensions are space like and one dimension is time like. However, such a continuum precludes the possibility of evolution of future from the present as all events exist "forever" so to speak on the continuum with the tenses past, present, and future merely being perceptions of different inertial frames. Such a far-reaching ontological concept, created by a mere convention, is yet to gain full acceptance. In this paper, we present arguments in favor of an absolute present, which means simultaneous events are simultaneous in all inertial frames, and subscribe to evolution of future from the present. [ABSTRACT FROM AUTHOR]

The Robertson-Walker (RW) metric, derived from the cosmological principle and Weyl's postulate, characterizes the ACDM cosmological model. Traditionally, in this framework, the assumption of a constant speed of light leads to specific cosmological time dilation (TD). However, because the Robertson-Walker metric lacks a way to define time dilation, the speed of light, like wavelength and temperature, may vary with cosmic time. The minimally extended varying speed of light (meVSL) model fits standard cosmological observations while considering the evolution of physical constants. One model-independent test for the meVSL model is cosmological time dilation. However, current data cannot distinguish between the meVSL model and the standard model. [ABSTRACT FROM AUTHOR]

A very simple, fundamental physical explanation is presented of time dilation and length contraction. This explanation is obtained from a classical model of physics that is Galilean. It assumes the existence of a medium (ether) that acts as an absolute reference in accordance with Mach's principle. Time and space are conventional, i.e., a three-dimensional space independent of time. In addition, the explanation relies on the assumption that all physics, including matter such as clocks and measuring rods, has a scalar wave structure. Matter is assumed to consist of locally stable scalar wave structures, specifically scalar standing wave structures. The scalar waves are just variations in space and time of medium density. Also, an element of special relativity is used, namely, the one taking into account the finite velocity of light. [ABSTRACT FROM AUTHOR]

The Friedmann–Lemaître–Robertson–Walker model establishes the correlation between redshifts and distances. It has a metric expansion of space. As a result, the wavelength of photons propagating through the expanding space is stretched, creating the cosmological redshift, z. It also relates the frequency of light detected by a local observer to that emitted from a distant source. In standard cosmology (i.e. a constant speed light model), this relation is given by a factor 1/(1 + z). However, this ratio is modified in the minimally extended varying speed of light model (meVSL, c  = c 0 a b /4) as 1/(1 + z)1 − b /4. This time dilation effect is detected as the observed rate of the time variation in the intensity of emitted radiation. The spectra of Type Ia supernovae (SNe Ia) provide a reliable way to measure the apparent aging rate of distant objects. We use data on 13 high-redshift (0.28 ≤ z ≤ 0.62) SNe Ia to obtain b  = 0.198 ± 0.415 at the 1-σ confidence interval. The current data is too sparse to give meaningful constrain on the meVSL and cannot distinguish the meVSL model from the standard model. [ABSTRACT FROM AUTHOR]

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Introduce a standard Euclidean geometric model with a maximum speed c, which may help us understand why the speed of light c is the universe's maximum speed, why parameter c is a constant, and the geometric mechanism that causes time dilation and length contraction. Finally, based on this model, this paper will present a new coordinate transformation and general velocity addition formula. The new general velocity addition formula is not only consistent with the Michelson-Morley experiment but also consistent with the one-way speed of light experiment and the linear Sagnac experiment. [ABSTRACT FROM AUTHOR]

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The speed of light is observed differently depending on the observer's velocity. Therefore, the Lorentz contraction cannot be derived; the length contraction is unnecessary in physics. Time dilation has been experimentally confirmed. Using Einstein and Feynman light clock, we show that the Lorentz time dilation is derived in Fresnel's ether. The Galilean transformation with Lorentz time dilation is introduced. [ABSTRACT FROM AUTHOR]

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One of the biggest unsolved problems in physics is explaining what time is. The paper explains what time is in kinematics theories. It has been proved that in the kinematics of Special Theory of Relativity (STR) and Special Theory of Ether (STE) time is measured by the light clock. Therefore, all properties of time in kinematics result from the properties of a signal clock. The paper explains the time dilation phenomenon on the basis of STE. The presented explanation is not only a classic description of time dilation but is based on the construction of an innovative technical model of this phenomenon. Time dilation is due to the properties of the light clock. It is a natural property of this clock. The article shows that the claim that the speed of light in a vacuum is the maximum speed in the real world has no theoretical basis. In modern physics, such a doctrine has been adopted as a result of an overinterpretation of the mathematics on which the Special Theory of Relativity is based. The presented model shows how, using atomic clocks, it may be possible to determine the movement in relation to the universal frame of reference in which electromagnetic signals propagate. This article contains only original research. [ABSTRACT FROM AUTHOR]

Generalized Doppler shift for light is derived by considering both velocity and acceleration, and is used to calculate time dilation ratio. A circular mirror used to measure time is transformed to the elliptical mirror in a reference frame when it is in motion. The special relativistic Doppler shift is calculated in any propagation direction of light for a constant velocity of motion. Furthermore, the generalized Doppler shift is derived by considering both the velocity and the acceleration effect. The ratio of the frequency shifts are shown as a function of velocity, acceleration, and detection angle. [ABSTRACT FROM PUBLISHER]

In General Relativity, the gravitational field of a spherically symmetric non-rotating body is described by the Schwarzschild metric. This metric is invariant under time reversal, which implies that the power series expansion of the time dilation contains only even powers of v / c . The weak-field post-Newtonian approximation defines the relativistic time dilation of order ϵ (or of order (v / c) 2 ) of the small parameter. The next non-zero term of the time dilation is expected to be of order ϵ 2 , which is impossible to measure with current technology. The new model presented here, called Relativistic Newtonian Dynamics, describes the field with respect to the coordinate system of a far-removed observer. The resulting metric preserves the symmetries of the problem and satisfies Einstein's field equations, but predicts an additional term of order ϵ 3 / 2 for the time dilation. This term will cause an additional periodic time delay for clocks in eccentric orbits. The analysis of the gravitational redshift data from the Galileo satellites in eccentric orbits indicates that, by performing an improved satellite mission, it would be possible to test this additional time delay. This would reveal which of the coordinate systems and which of the above metrics are real. In addition to the increase of accuracy of the time dilation predictions, such an experiment could determine whether the metric of a spherically symmetric body is time reversible and whether the speed of light propagating toward the gravitating body is the same as the speed propagating away from it. More accurate time dilation and one-way speed of light formulas are important for astronomical research and for global positioning systems. [ABSTRACT FROM AUTHOR]

Our mind seems to be formatted to imagine a "motionless" material particle (or more accurately a region of spacetime at rest relative to that material particle) fixed in space as an absolute reference and to consider the existence of space and time as independent universal entities, as we perceive when we measure them with a ruler and a clock, respectively. Instead, let us first hypothesize that singularities are the absolute reference for the universe, that the speed of light in vacuum (c = 299 792 458 m/s) is universal and absolute, and that deceleration/acceleration is the "driving force" that defines spacetime. Frames of reference anchored on material particles/objects may be grouped as having zero acceleration (inertial frames), nonzero, constant acceleration (pseudoinertial frames) or nonzero, variable acceleration (noninertial proper frames), so that a noninertial proper frame may be considered as composed of an infinite number of pseudoinertial frames. The universality of c is ensured by its absolute constancy, when both observer and moving beam of photons are in frames of reference differing neither in speed nor in acceleration, as is the case within inertial or pseudoinertial frames, respectively. However, its value (as that of any other speed) is measured as different when the observer is at an inertial or pseudoinertial frame and the beam of photons is moving in another, thus differing in Lorentz factor (c) or acceleration, respectively. Speed, velocity, and acceleration (including the effect of gravity on a material particle/object) are all defined in terms of space and time. However, space and time do not exist as independent universal entities, as they are integral components of one and the same inextricable physical entity, spacetime. Assuming spacetime forms a continuum, it is expected that anything affecting one will affect the other. This has been widely recognized for gravity, but not for speed--something which becomes clearer if we assume that it should in fact be acceleration/deceleration that moves a material particle from one frame of reference into another. Several conditions that are grouped under gravity-dependent and non-gravity-dependent act individually or in combination to submit a matter particle to acceleration. Therefore, when perceived from the Earth (or any other place at v < 299 792 458 m/s), any departure from c caused by deceleration should expand space and contract time. Any further deceleration or subsequent acceleration (for as long as v< c) will alter spacetime. Hence, in astrophysics, deceleration rather than acceleration should be the main driving or direct physical quantity. It is proposed that any deceleration/acceleration distorts spacetime. A method to combine the effects of several conditions that define the acceleration status of a material particle in spacetime is proposed. The higher v/c and/or gravity-dependent acceleration, the greater time dilation and space contraction will be. At the singularity, time dilation and space contraction will be maxima. The actual "position" of a material particle in spacetime may therefore be defined by the sum of all changes it suffered in deceleration/acceleration (due to changes in gravity-dependent and non-gravity-dependent accelerations) since the singularity. The impossibility of exceeding the speed of light in vacuum is discussed and tentatively demonstrated. In line with the present hypothesis, both time and space are relative, but only partially due to the limits imposed by c, opening the possibility for the concept of spacetime partial relativity. According to our proposal, spacetime is defined by a special form of deceleration, which we have termed relativistic or Lorentz deceleration: it is a decelerationdependent elastic property of any matter particle moving at v < c. It expands/contracts precisely because of the effect of deceleration/acceleration on matter particles moving at v < c. According to these views, defining a singularity should depend on the perspective. When perceived from the Earth or any other place at v < c, a singularity is a spaceless point of infinite density, associated with the speed of light and where a second lasts forever. However, when "perceived" from within a singularity, space is there and time flows. Based on this work, a singularity may be defined in higher detail as the embryonic state of the universe (or a part of it), associated with two universal absolute constants: the speed of photons (c = 299 792 458 m/s) and the quantity of spacetime. It also corresponds to a standard spacetime condition, in which time is dilated and space contracted to maximum values. The Big Bang is interpreted not as an explosion or bang, but rather as an infinitesimal deceleration from the singularity, thus triggering the initial exponential space expansion and time contraction and leading to matter formation. Neither space nor time are created or destroyed--They are always there since the singularity but vary widely in contraction/expansion magnitude with each precise spacetime condition, as deceleration-dependent fluctuations take place in spacetime. Gravity, an inherent property of matter, and entropy are key players in the subsequent evolution of the universe. Uncountable successive and cumulative changes in deceleration suffered by material particles determine the precise conditions they occupy at each moment in spacetime, thus allowing the build-up of a gigantic and highly dynamic noninertial frame of reference, i.e., our universe. Individual observers at single points of the universe should all see light photons moving in vacuum at 299 792 458 m/s (or any material particle/object moving at v < 299 792 458 m/s) and perceive space and time identically, each within their own spacetime condition. Differences arise only when one observer "looks" at other observers in distinct spacetime conditions. An attempt is made to interpret spacetime and light when we "look" at frames of reference distinct from our own, since this is precisely what we "see" when we observe the universe from the Earth. Cosmological models are typically based on several assumptions. The hypothesis formulated in the present article is no different, with a singularity as its major reference. We conceptualize on a cosmological model that challenges some currently accepted views of the universe. [ABSTRACT FROM AUTHOR]

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This essay considers that free-space appears to be composed of an energy field with characteristics of an elastic medium evenly dispersed across the Cosmos in an optimal high state of entropy. This spatial energy field or SEF has properties that may explain inertia and gravity. Linear and angular momentum appear to emerge from these properties. SEF is stretched and compressed in the presence of mass. In addition, compression of space by high inertial events slows the flow of time, similar to gravitational time dilation. This is presented as a new concept and called inertial time dilation. Also, it is proposed that the speed of light c is an intrinsic self-imposed limit due to characteristics of space (SEF) as exemplified by the physical constants eo and lo representing electric permittivity and magnetic permeability. [ABSTRACT FROM AUTHOR]

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This article discusses the topic of interstellar travel and its challenges. It highlights the common misconception that distances between celestial objects are much larger than the objects themselves. The article also explores the concept of relativity and its potential implications for space travel. It presents a mathematical equation that can be used to calculate ship time for long journeys, taking into account the effects of acceleration and time dilation. The article concludes by acknowledging the various practical and human factors that would need to be considered for extended space travel. [Extracted from the article]

Statements about relativistic effects are often subtle. In this essay we will demonstrate that the three classical tests of general relativity, namely perihelion precession, deflection of light and gravitational redshift, are passed perfectly by an extension of Newtonian gravity that includes gravitational time dilation effects while retaining a non-relativistic causal structure. This non-relativistic gravity theory arises from a covariant large speed of light expansion of Einstein's theory of gravity that does not assume weak fields and which admits an action principle. [ABSTRACT FROM AUTHOR]

We review how the kinematic structures of special relativity and quantum mechanics both stem from the relativity principle, i.e., "no preferred reference frame" (NPRF). Essentially, NPRF applied to the measurement of the speed of light c gives the light postulate and leads to the geometry of Minkowski space, while NPRF applied to the measurement of Planck's constant h gives "average-only" projection and leads to the denumerable-dimensional Hilbert space of quantum mechanics. These kinematic structures contain the counterintuitive aspects ("mysteries") of time dilation, length contraction, and quantum entanglement. In this essay, we extend the application of NPRF to the gravitational constant G and show that it leads to the "mystery" of the contextuality of mass in general relativity. Thus, we see an underlying coherence and integrity in modern physics via its "mysteries" and the fundamental constants c, h, and G. It is well known that Minkowski and Einstein were greatly influenced by David Hilbert in their development of special relativity and general relativity, respectively, but relating those theories to quantum mechanics via its non-Boolean Hilbert space kinematics is perhaps surprising. [ABSTRACT FROM AUTHOR]

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We consider a thought experiment, equivalent to the Sagnac effect, where a light signal performs a round trip over a closed path. If special relativity (SR) adopts Einstein synchronization, the result of the experiment shows that the local light speed cannot be c in every section of the closed path. No inconsistencies are found when adopting absolute synchronization. Since Einstein and absolute synchronizations can be discriminated, the conventionality of the one-way speed of light holds no longer. Thus, as sustained by specialists, it might be a viable formulation of SR that reinstates the conservation of simultaneity, even though it allows for relativistic effects, such as time dilation. Such an approach may lead to the discovery of new effects and a better understanding of relativistic theories. [ABSTRACT FROM AUTHOR]

We present a comprehensive discussion of the formulation of the kinematics of special relativity, i.e., the Lorentz transformation. We begin with a concise new proof that the principle of relativity implies that the transformation of event coordinates between inertial reference frames is linear. We then give a clear derivation of the pre-Lorentz transformation, which follows from the principle of relativity. We then show that the pre-Lorentz transformation and the inertial invariance of the speed of light together result in the Lorentz transformation. This, of course, is essentially the traditional formulation. We next present two additional formulations, one using Lorentz–Fitzgerald contraction and one using time dilation, instead of inertial invariance. This is reasonable since Lorentz–Fitzgerald contraction and time dilation are about as well established as and are arguably less abstract than inertial invariance, and thus may profitably be used instead of inertial invariance to complete the formulation. We then present a complete proof that the pre-Lorentz transformation and the requirement of closure upon composition together imply that the transformation is either a Galilean transformation or a generalized Lorentz transformation. This is noteworthy in that it gets ever so close to the Lorentz transformation without invoking light. In the course of this, we obtain a generalized velocity addition rule, which reduces to the velocity addition rule of special relativity. We next show that the generalized Lorentz transformation, together with inertial invariance, Lorentz–Fitzgerald contraction, and time dilation, used one at a time, yields three more formulations. We then show that the unspecified, nonzero, constant speed in the generalized Lorentz transformation can be determined without any reference to light, thereby obtaining a seventh formulation. Light plays no explicit role in the four formulations employing Lorentz–Fitzgerald contraction and time dilation and plays no role whatsoever in the seventh formulation. Thus, and this is a fact which should be strongly emphasized, the formulation of special relativity in no way depends upon the nature of electromagnetic radiation. We conclude by briefly discussing these seven formulations of the kinematics of special relativity and some associated implications. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the biggest unsolved problems in physics is explaining what time is. The paper explains what time is in kinematics theories. It has been proved that in the kinematics of Special Theory of Relativity (STR) and Special Theory of Ether (STE) time is measured by the light clock. Therefore, all properties of time in kinematics result from the properties of a signal clock. The paper explains the time dilation phenomenon on the basis of STE. The presented explanation is not only a classic description of time dilation but is based on the construction of an innovative technical model of this phenomenon. Time dilation is due to the properties of the light clock. It is a natural property of this clock. The article shows that the claim that the speed of light in a vacuum is the maximum speed in the real world has no theoretical basis. In modern physics, such a doctrine has been adopted as a result of an overinterpretation of the mathematics on which the Special Theory of Relativity is based. The presented model shows how, using atomic clocks, it may be possible to determine the movement in relation to the universal frame of reference in which electromagnetic signals propagate. This article contains only original research.

ABSTRACT Our understanding of the universe has changed widely since Einstein's explanation of time as an axis. In this paper, we aim to study the effect of traveling at speeds beyond the limit assigned by Einstein in his theory of relativity. Using his very equations for time dilation, we will show that it is not only possible to break down the barriers of time, but also to predict with certainty about the effects that a body will undergo if it travels beyond the limit of the speed of light. This article deals with the mathematical proof of time travelling and the derivation of a general formula that is applicable for all speeds greater than, the speed of light. The extent of time dilation will also be under discussion. This article concludes the variation in the dilation of time with concluding help of exemplary questions and the extended articles used in the relativity equations. The methods and the conclusion of our paper conclude the result in favor of relative extension of time. Objectives: To study the influence of different speeds greater than light on the rest or proper time using Einstein's equation of time dilation from the special theory of relativity. To study the relativity equation related to the dilation of time. The possibilities of the time dilation regarding the various masses in case of exceeding the speed of light. [ABSTRACT FROM AUTHOR]

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The author’s previous papers on superluminal time dilation [E. J. Betinis, Phys. Essays 11, 81 (1998)] and the superluminal Schrödinger equation [E. J. Betinis, Phys. Essays 11, 311 (1998)] are mentioned in order to inform the reader of the existence of the superluminal theories developed to date. The superluminal time dilation is utilized in the derivation of the Lorentz transformations in order to show as a first step that the superluminal theory for physics is valid and can maintain the invariance of the metric. Next the most general Einstein equation of gravitation is reduced to the special case of finding the weak and static fields of the gravitational potential for the universe and one receding galaxy. This case is further simplified by assuming that the receding galaxy is only moving radially from the center of the universe. It is found that by restricting the moving galaxy to having a velocity less than the speed of light c (the subluminal case), the turning point or “stopping point” of the receding galaxy would fall far short of the distance of the known observed outermost galaxy. By Hubble’s law, it is shown that the outermost galaxy would have a velocity greater than the speed of light, so the subluminal restriction also contradicts Hubble’s law as well. The superluminal formulation shows that the turning point if it exists can occur at the present assumed location of the outermost galaxy where its velocity is greater than the velocity of light. However, since observations presently show that the outermost galaxy is still receding at a velocity greater than the velocity of light c, the universe does not, at present, seem to be contracting or to be oscillatory. In addition, then the superluminal treatment for finding the gravitational potential as it allows a velocity greater than the velocity of light is also consistent with the Hubble’s law calculation of the velocity of the outermost receding galaxy. In the above formulation of the weak and static gravitational fields of the Einstein equation, spacetime is not really totally flat but is slightly curved. In addition, the group theory aspects of the Lorentz transformations for both the subluminal and superluminal cases are demonstrated. [ABSTRACT FROM AUTHOR]

A transverse "Doppler" effect is not by necessity the result of time dilation but may result from light traveling relative to a set. of coordinates apart from the coordinates of the source. [ABSTRACT FROM AUTHOR]

The phase shift induced by a uniform rotation in a Michelson interferometer is re-derived in the geometrical framework of the coordinate-free formalism of general relativity from the co-rotating point of view. The effect is second order in the ratio of the interferometer's speed to the speed of light and further suppressed by the ratio of the length of the interferometer's arms to the radius of rotation. The relation of the effect to gravitational time dilation is discussed. [ABSTRACT FROM AUTHOR]

We present a Relativistic Newtonian Dynamics ( R N D ) for motion of objects in a gravitational field generated by a moving source. As in General Relativity ( G R ), we assume that objects move by a geodesic with respect to some metric, which is defined by the field. This metric is defined on flat lab spacetime and is derived using only symmetry, the fact that the field propagates with the speed of light, and the Newtonian limit. For a field of a single source, the influenced direction of the field at spacetime point x is defined as the direction from x to the to the position of the source at the retarded time. The metric depends only on this direction and the strength of the field at x. We show that for a static source, the R N D metric is of the same form as the Whitehead metric, and the Schwarzschild metric in Eddington–Finkelstein coordinates. Motion predicted under this model passes all classical tests of G R . Moreover, in this model, the total time for a round trip of light is as predicted by G R , but velocities of light and object and time dilation differ from the G R predictions. For example, light rays propagating toward the massive object do not slow down. The new time dilation prediction could be observed by measuring the relativistic redshift for stars near a black hole and for sungrazing comets. Terrestrial experiments to test speed of light predictions and the relativistic redshift are proposed. The R N D model is similar to Whitehead's gravitation model for a static field, but its proposed extension to the non-static case is different. This extension uses a complex four-potential description of fields propagating with the speed of light. [ABSTRACT FROM AUTHOR]

The "Breakthrough Starshot" program is planning to send transrelativistic probes to travel to nearby stellar systems within decades. Because the probe velocity is designed to be a good fraction of the light speed, Zhang & Li recently proposed that these transrelativistic probes can be used to study astronomical objects and to test special relativity. In this work, we propose some methods to test special relativity and constrain photon mass using the Doppler effect with the images and spectral features of astronomical objects as observed in the transrelativistic probes. We introduce more general theories to set up the framework of testing special relativity, including the parametric general Doppler effect and the Doppler effect with massive photons. We find that by comparing the spectra of a certain astronomical object, one can test Lorentz invariance and constrain photon mass. Additionally, using the imaging and spectrograph capabilities of transrelativistic probes, one can test time dilation and constrain photon mass. For a transrelativistic probe with velocity v ∼ 0.2c, aperture D ∼ 3.5 cm, and spectral resolution R ∼ 100 (or 1000), we find that the probe velocity uncertainty can be constrained to σv ∼ 0.01c (or 0.001c), and the time dilation factor uncertainty can be constrained to (or 0.001), where is the time dilation factor and γ is the Lorentz factor. Meanwhile, the photon mass limit is set to mγ ≲ 10−33 g, which is slightly lower than the energy of the optical photon. [ABSTRACT FROM AUTHOR]

This paper introduces a new theory called, "the theory of absolutivity", which challenges the two postulates of the special theory of relativity (special relativity). This paper analyzes how special relativity derives the time dilation, and then explains how it leads to a disagreement on the first postulate: the principle of relativity. Next, this paper continues to explain a disagreement on the second postulate: the universal speed of light. Furthermore, the paper written by Gjurchinovski on the reflection of light from a uniformly moving mirror is interpreted to give a classical explanation for the null result of Michelson-Morley experiment, by justifying Lorentz contraction of length without referring to special relativity. [ABSTRACT FROM AUTHOR]

Copyright of Physics Essays is the property of Physics Essays Publication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)