Search

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]

Subjective time dilation is an effect discovered using the oddball paradigm, where expanding visual stimuli, but not shrinking ones, induce a prolongation of subjective temporal perception compared to static stimuli. This disparity is often seen as another demonstration of humans' evolved reaction to approaching threats, since visual expansion resembles approaching potential threats and warrants extra attention. In this study, we show that by manipulating the relative sizes of stimuli, both expanding and shrinking stimuli can induce prolongation of subjective time in an oddball paradigm. We propose an alternative explanation based on information theory, linking subjective temporal perception to entropy, an objective property of stimulus that is information uncertainty. Temporal function as a logistic function thus serves as the framework inside which content functions like information processing are able to operate coherently. [ABSTRACT FROM AUTHOR]

Whether they are theologians, lay people, or non-believers, most have at least anecdotally heard of the miracle of Jesus walking on water. Many important lessons and insights can be gleaned from this important passage, including testimony to the identity of Jesus that bolsters belief in Him and His deity and a non-trivial display of Jesus' power over His creation. However, was God trying to convey more than just His ability to elude physics, and displaying His authority over the dimension of time and its creation? The dimension of time is an elusive and much debated dimension that is difficult to understand, and in the context of God and heaven, it is in many respects beyond human comprehension. However, as expressed by Albert Einstein, "the distinction between the past, present and future is only a stubbornly persistent illusion." This illusion can only be unlocked by God, and thus it was created by God. In this article, the miracle of Jesus walking on water is explored in relation to the phenomenon of gravitational time dilation; it is considered as an instance that reveals God's relation to time, as well as the complexity and awesomeness of creation in general. We show that the equations for time dilation around a massive body may serve as a model to show the independence of God from His creation of spacetime. [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]

Time-resolved studies have so far relied on rapidly triggering a photo-induced dynamic in chemical or biological ions or molecules and subsequently probing them with a beam of fast moving photons or electrons that crosses the studied samples in a short period of time. Hence, the time resolution of the signal is mainly set by the pulse duration of the pump and probe pulses. In this paper, we propose a different approach to this problem that has the potential to consistently achieve orders of magnitude higher time resolutions than what is possible with laser technology or electron beam compression methods. Our proposed approach relies on accelerating the sample to a high speed to achieve relativistic time dilation. Probing the time-dilated sample would open up previously inaccessible time resolution domains. [ABSTRACT FROM AUTHOR]

Time dilation (TD) is a principal concept in the special theory of relativity (STR). The Einstein TD formula is the relation between the proper time t 0 measured in a moving frame of reference with velocity v and the dilated time t measured by a stationary observer. In this paper, an integral approach is firstly presented to rededuce the Einstein TD formula. Then, the concept of TD is introduced and examined in view of the fractional calculus (FC) by means of the Caputo fractional derivative definition (CFD). In contrast to the explicit standard TD formula, it is found that the fractional TD (FTD) is governed by a transcendental equation in terms of the hyperbolic function and the fractional-order α. For small v compared with the speed of light c (i.e., v ≪ c ), our results tend to Newtonian mechanics, i.e., t → t 0 . For v comparable to c such as v = 0.9994 c , our numerical results are compared with the experimental ones for the TD of the muon particles μ + . Moreover, the influence of the arbitrary-order α on the FTD is analyzed. It is also declared that at a specific α , there is an agreement between the present theoretical results and the corresponding experimental ones for the muon particles μ + . [ABSTRACT FROM AUTHOR]

We present a novel test of the cosmological principle: the idea that, on sufficiently large scales, the Universe should appear homogeneous and isotropic to observers comoving with the Hubble flow. This is a fundamental assumption in modern cosmology, underpinning the use of the Friedmann–Lemaître–Robertson–Walker metric as part of the concordance ΛCDM paradigm. However, the observed dipole imprinted on the cosmic microwave background (CMB) is interpreted as our departure from the Hubble flow, and such a proper motion will induce a directionally-dependent time dilation over the sky. We illustrate the feasibility of detection of this 'time dilation dipole' and sketch the practical steps involved in its extraction from a catalogue of sources with intrinsic time-scales. In essence, whilst the scale of this dilation is small, being of the order of 0.1 per cent, it will in principle be detectable in large-scale surveys of variable cosmological sources, such as quasars and supernovae. The degree of alignment of the time dilation dipole with the kinematic dipole derived from the CMB will provide a new assessment of the cosmological principle and address the tension in dipole measures from other observations. [ABSTRACT FROM AUTHOR]

Relativistic time deals with concepts as spacetime and time dilation. I will try to explain this as clearly as possible. To explain the concept of spacetime is not at all impossible, although it is four-dimensional. But that means that we define it using four numbers. If we describe us through age, weight, height, and IQ, that would be a fourdimensional representation of us. [ABSTRACT FROM AUTHOR]

Researchers in standard gravity theory and cosmology seldom take into account Lorentz relativistic mass. The dismissal of Lorentz relativistic mass by the research community has happened without first properly investigating what predictions incorporating it in gravity models have led to. We show that the inclusion of Lorentz relativistic mass in some gravity theories has a dramatic impact on the predicted redshift from objects with high gravitational field such as stellar objects fitting the mathematical properties of black holes. Taking into account Lorentz relativistic mass provides diverse interpretations of quasars and many other objects. As relevant example, it may explain the lack of observed velocity time dilation in quasars. [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]

In special relativity, the time dilation formula has been obtained by particles propagation in a straight line trajectory relative to an observer in motion. Up to now, there are no available formulas for other possible trajectories of particles. However, this paper obtains formulas of time dilation for several trajectories of particle such as parabolic, elliptic, and circular and finds a relatively accurate trajectory. The obtained formulas are employed in order to analyze the time dilation of the muon particles decay. In this paper, it is found that the time dilation of the parabolic and the elliptical trajectories exceed the corresponding results utilizing the standard Lorentz-Einstein time dilation formula. Consequently, if we are able to control the trajectory of unstable particles by some external forces, then their life-times might be increased. Probably, the increase in lifetime via a curved trajectory occurs at lower relative velocity & acceleration energy if compared to the straight line trajectory. In addition, the circular trajectory leads to multiple values of time dilation at certain velocities of an observer in motion, which may give an interpretation of fluctuations of time dilation in quantum mechanics. The result arises from the present relatively accurate formula of time dilation that is very close to the experimental data of muon decay (CERN experiment) when it is compared to the result obtained by the Lorentz-Einstein formula. Finally, it may be concluded that the time dilation not only depends on relative velocity and acceleration energy of particles but also on curved trajectories. The present work may attract other researchers to study different trajectories. [ABSTRACT FROM AUTHOR]

The authors consider a game problem of soft meeting of controlled oscillating systems, i.e., their simultaneous convergence in geometric coordinates and velocities. Applying Pontryagin's first direct method [1] to solve this problem is noted to be impossible since the condition underlying this method is not satisfied. This condition is an instantaneous advantage of the pursuer (the one who strives to achieve this meeting) over the evader (the one who tries to avoid it). In the method, we apply the principle of time dilation, which weakens this condition and makes it possible to terminate the game in a finite time. The paper outlines the problem solution method that employs a certain time dilation function. Also, an algorithm, versions of constructing pursuer's control, and an example of computer implementation of the process of convergence on the plane are provided. [ABSTRACT FROM AUTHOR]

This essay weaves together elements of the concepts of spacetime, demons and the U.S. popular culture concept of demon time to postulate the end of the world and bring a conclusion to white supremacist and anti-African American worlds. Topics discussed are Black posthumanism as the foundation of Black transhumanism or technological materialization, time dilation as an element for understanding how African Americans experience time, and demon time as a way to bring African American realities.

Time dilation (TD) is a principal concept in the special theory of relativity (STR). The Einstein TD formula is the relation between the proper time t0 measured in a moving frame of reference with velocity v and the dilated time t measured by a stationary observer. In this paper, an integral approach is firstly presented to rededuce the Einstein TD formula. Then, the concept of TD is introduced and examined in view of the fractional calculus (FC) by means of the Caputo fractional derivative definition (CFD). In contrast to the explicit standard TD formula, it is found that the fractional TD (FTD) is governed by a transcendental equation in terms of the hyperbolic function and the fractional-order α. For small v compared with the speed of light c (i.e., v≪c), our results tend to Newtonian mechanics, i.e., t→t0. For v comparable to c such as v=0.9994c, our numerical results are compared with the experimental ones for the TD of the muon particles μ+. Moreover, the influence of the arbitrary-order α on the FTD is analyzed. It is also declared that at a specific α, there is an agreement between the present theoretical results and the corresponding experimental ones for the muon particles μ+.

In special relativity, the time dilation formula has been obtained by particles propagation in a straight line trajectory relative to an observer in motion. Up to now, there are no available formulas for other possible trajectories of particles. However, this paper obtains formulas of time dilation for several trajectories of particle such as parabolic, elliptic, and circular and finds a relatively accurate trajectory. The obtained formulas are employed in order to analyze the time dilation of the muon particles decay. In this paper, it is found that the time dilation of the parabolic and the elliptical trajectories exceed the corresponding results utilizing the standard Lorentz-Einstein time dilation formula. Consequently, if we are able to control the trajectory of unstable particles by some external forces, then their life-times might be increased. Probably, the increase in lifetime via a curved trajectory occurs at lower relative velocity & acceleration energy if compared to the straight line trajectory. In addition, the circular trajectory leads to multiple values of time dilation at certain velocities of an observer in motion, which may give an interpretation of fluctuations of time dilation in quantum mechanics. The result arises from the present relatively accurate formula of time dilation that is very close to the experimental data of muon decay (CERN experiment) when it is compared to the result obtained by the Lorentz-Einstein formula. Finally, it may be concluded that the time dilation not only depends on relative velocity and acceleration energy of particles but also on curved trajectories. The present work may attract other researchers to study different trajectories.

The authors propose a method for solving the game problem where the trajectory of a quasi-linear non-stationary system approaches a cylindrical terminal set varying with time. The case is considered where Pontryagin's condition (the condition of the first player's advantage) is not satisfied. A time dilation function is introduced, which postpones the time of game termination and is used to introduce a modified Pontryagin's condition, which allows making a measurable choice of control. The basic method is the method of resolving functions. Using the technique of set-valued mappings and their selectors, the strategies are generated, which guarantee the problem solution. The process of convergence of the trajectory and the terminal set consists of two sections: active and passive, where the control of the first player is selected using the control of the second player with a certain time delay, which depends on the time dilation function. The scheme of the method is outlined and sufficient conditions for the game termination in a finite time are obtained. [ABSTRACT FROM AUTHOR]

This paper develops the approach to special relativity put forward by John S. Bell. The classical dynamics of an electron orbiting a nucleus in uniform motion is solved analytically and compared to numerical simulations for an accelerated nucleus. The relativistic phenomena of length contraction and time dilation are shown to result from the electric and magnetic forces on the electron when its motion is analyzed in a single frame of reference. The relevance of these results for understanding the theory of special relativity is discussed. In this paper, the author explores a suggestion by John Bell for teaching special relativity: to introduce length contraction and time dilation as dynamical phenomena arising from the laws of motion, without reference to the Lorentz transformations. The paper provides historical and philosophical insight into the development of special relativity alongside an analysis of electron orbits in a classical model of an atom. Using only the Lorentz force law, the author illustrates the deformation of orbits of moving and accelerating atoms with approximate, exact, and numerical calculations that reveal time dilation and length contraction. Instructors may find these derivations useful in teaching courses on modern physics, relativity, classical mechanics, electrodynamics, or numerical methods. [ABSTRACT FROM AUTHOR]

For the first time, the possibility of measuring the difference in gravitational potentials and orthometric heights by a quantum level based on the gravitational effect of time dilation using ground communication lines is considered. The duplex mode of measurements using two opposite radio channels is theoretically described. The dilation effect was experimentally measured using a one-way radio communication line implemented based on a fiber-optic link. For measurements, stationary and mobile (transportable) quantum hydrogen clocks were used with relative instabilities of (0.5-0.7)×10-15 and 1×10-15, respectively. It was found that in the experiment, the gravitational redshift of the frequency between the utilized clocks has two components: the redshift of the master oscillator frequency and the classical redshift in the radio channel. Based on the measurement results, the displacement height of the transportable quantum hydrogen clock was calculated to be (–34.0 ± 0.8) m, while the actual height was –34 m. [ABSTRACT FROM AUTHOR]

Einstein's special and general relativity are relics from before quantum physics. If forces are transmitted by quanta, this must also apply to gravity. As light consist of quanta, it is only logical that gravitational quanta interact with light. In my article "Cognitive bias in physics with respect to Einstein's relativity, demonstrated by the famous experiment of Pound and Rebka (1960), which in reality refutes Einstein's general relativity" [R. G. Ziefle, Phys. Essays 35, 91 (2022)], I could demonstrate that Einstein's "proper time" t0 does not refer to reference frames but to gravitational potentials. That is why "Newtonian quantum gravity" [R. G. Ziefle, Phys. Essays 33, 99 (2020)] can predict the correct curvature of a light beam at the surface of the Sun. Also, the phenomena observed at the binary pulsar PSR B1913þ16 can precisely be predicted by merely applying Kepler's second law. If gravitational quanta move away from masses with the constant speed c of light, this coincides with Einstein's postulate of a constant speed c of light with respect to reference frames, as a mass, such as a star or a planet, can also be defined as a reference frame. Therefore, Einstein's found by chance an artificial and complicated method to calculate changes in space-time caused by motion, which are in reality additional gravitational effects caused by the relative velocity between gravitational quanta emitted by masses and other masses or photons. [ABSTRACT FROM AUTHOR]

This article describes the analytical estimation of time dilation along the elliptical orbit of a satellite due to effects of relativity where the functioning has been time-dependent. The satellites in circular orbit are calibrated as moving frame of reference at constant velocity in constant non inertial frame of reference, namely Global Positioning System satellites where effects of both relativistic and gravitational time dilations can be seen. This article deals with the variation of the time dilation along the elliptical orbit whose speed of reference frame varies with respect to time and also varying the non-inertial frame of reference. The relativistic effects on the time dilation, is caused by the Earth rotation, due to the orbit eccentricity. The estimated values have a scope in the field of space mechanics. As a result the plot has been intended along the orbit comparing to circular orbit in both special and general relativity perspective.

Reciprocal length contraction and time dilation, as enshrined in the Lorentz transformation, are the bulwark of the special relativity theory. Reciprocal time dilation is typically discussed (in the context of its apparent contradiction) and usually explained away as the result of differing synchronization in inertial reference frames and the relativity of simultaneity. Further, it is generally suggested that time is an abstract concept, and its perceptions may differ with context. However, we suggest that regarding length measurements no such abstraction can be envisaged. In this manuscript, we examine the reciprocal length contraction in detail to assess whether it leads to any contradiction. [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.)

The explanation of Einstein’s special theory of relativity in his original 1905 paper is examined. His analysis is confusing, as terms x, y, z, t, etc., have different meanings at various points, and he presents equations based on different and inconsistent assumptions. Adding subscripts clarifies these issues but exposes errors in his reasoning. To calculate his transformation equations, he selects a combination of equations which gives results matching the Lorentz transformation but he ignores other possible valid solutions. Also his calculations contain serious errors. Therefore, he fails to prove that his theory leads to the Lorentz equations as a unique solution. Einstein’s analysis includes “moving” clocks which show “stationary” time t, so the idea that a moving clock should run slower than a stationary clock is incompatible with his theory. Also, his calculation of time dilation contains serious errors. As a result, he fails to provide a theoretical justification for his famous “clocks paradox.” [ABSTRACT FROM AUTHOR]

Our experience of time is strikingly plastic: Depending on contextual factors, the same objective duration can seem to fly by or drag on. Perhaps the most direct demonstration of such subjective time dilation is the oddball effect: when seeing identical objects appear one after another, followed by an "oddball" (e.g., a disc that suddenly grows in size, in a sequence of otherwise static discs), observers experience this oddball as having lasted longer than its nonoddball counterparts. Despite extensive work on this phenomenon, a surprisingly foundational question remains unasked: What actually gets dilated? Beyond the oddball, are the objects just before (or just after) the oddball also dilated? As in previous studies, observers viewed sequences of colored discs, one of which could be the oddball—and subsequently reproduced the oddball's duration. Unlike previous studies, however, there were also critical trials in which observers instead reproduced the duration of the disc immediately before or after the oddball. A clear pattern emerged: oddball-induced time dilation extended to the post-oddball disc, but not the pre-oddball disc. Whence this temporal asymmetry? We suggest that an oddball's sudden appearance may induce uncertainty about what will happen next, heightening attention until after the uncertainty is resolved. [ABSTRACT FROM AUTHOR]

Background: This study aims to compare patency rates of the 0- and 30-s (sec) balloon dilation time in hemodialysis (HD) patients with restenosis after percutaneous transluminal angioplasty (PTA). Methods: The patients who underwent PTA within 6 months for failed arteriovenous fistula at the forearm were randomly assigned the 0-s or 30-s dilation time group. Effect of dilation time on the 3- and 6-month patency rates after PTA was examined. Results: Fifty patients were enrolled in this study. The 3-month patency rate in the 30-s dilation group was better than that in the 0-s dilation group (P = 0.0050), while the 6-month patency rates did not show a significant difference between the two groups (P = 0.28). Cox's proportional hazard model revealed that 30-s of inflation time (hazard ratio 0.027; P = 0.0072), diameter of the proximal (hazard ratio 0.32; P = 0.031), and dilation pressure (hazard ratio 0.63; P = 0.014) were associated with better 3-month patency. Dilation pressure between previous and present PTA did not differ in the 0-s (P = 0.15) and 30-s dilation groups (P = 0.16). The 6-month patency rate of the present PTA in the 30-s dilation group was higher than that of the previous PTA (P = 0.015). The visual analog scale did not differ between the two groups (P = 0.51). Conclusion: The presenting data suggest that 30-s dilation potentially results in a better 3-month patency rate than 0-s dilation in HD patients with restenosis after PTA. [ABSTRACT FROM AUTHOR]

Recently, the physics education community has taken a keen interest in modernising physics education. However, while topics in modern physics have great potential to engage students, these topics are abstract and hard-to-visualise. Therefore, many students hold mistaken pictures and misconceptions, which can impede learning. In this article, we expose a pervasive misconception about relativistic time dilation by presenting a thought experiment illustrating the difference between visual observation and coordinate measurement. We also point out how existing language can mislead and confuse students. In response, we describe an instructional approach that introduces world-maps, world-pictures and event-diagrams to clarify the applicability of key equations in special relativity for improved understanding. By unpacking 'the invisibility of time dilation' from the perspectives of both physics and pedagogy, we aim to help teachers provide clearer instruction. [ABSTRACT FROM AUTHOR]

Introductory textbooks for the theory of special relativity discuss the time dilation effect after introducing the Lorentz transformations. Reading the dictum 'moving clocks run slow' a student is likely to have the impression that this is a measured effect. On the other hand, after considering the relativistic Doppler effect the same student might be puzzled that this effect depends on the relative emitter-observer direction, contrary to Einstein's time dilation. Simple thought experiments are presented here where the inferred time dilation and the observed relativistic Doppler effect give quite opposite answers. Before solving the puzzle, we show how easily one can get confused and obtain apparently contradictory results. [ABSTRACT FROM AUTHOR]

The theory of special relativity is one of the most significant achievements in modern physics, with several important predictions such as time dilation, size contraction for a moving object, and mass-energy equivalence. Recent studies have demonstrated size contraction for an antiferromagnetic (AFM) domain wall (DW). Here, we show the excitation of terahertz (THz) magnons from a moving AFM DW under the magnetic anisotropy energy gradient. The energy of magnons comes from the loss of the effective DW mass due to the reduction in anisotropy energy. Also, the excitation of THz magnons is accompanied by a DW width broadening, overcoming the Lorentz contraction effect. Our results pave the way to study relativistic physics in AFM textures and to efficiently generate THz magnons by DC electric means. [ABSTRACT FROM AUTHOR]

The perceived duration of time does not veridically reflect the physical duration but is distorted by various factors, such as the stimulus magnitude or the observer's emotional state. Here, we showed that knowledge about an event's termination time is another significant factor. We often experience time passage differently when we know that an event will terminate soon. To quantify this, we asked 33 university students to report a rotating clock hand's duration with or without a termination cue that indicated the position at which the clock hand disappeared. The results showed that the presence of the termination cue dilated perceived durations, and the dilating effect was larger when the stimulus duration was longer, or the speed of the rotating stimulus was slower. A control experiment with a start-cue excluded the possibility that the cue's mere existence caused the results. Further computational analyses based on the attention theory-of-time perception revealed that the size of dilation is best explained by neither an event's duration nor the distance traveled by the clock hand, but by how long the clock hand spends time near the termination cue. The results imply that an event-termination cue generates a field in which the perceived time dilates. [ABSTRACT FROM AUTHOR]

We demonstrate that the de Broglie wave of a particle in a gravitational field turns toward the region of lower gravitational potential, causing the particle to fall. This turning is caused by clocks running slower in the smaller potential. We use the analogy of ocean waves that are slower in shallower water and turn toward beaches. This approach implies that the motion is along a geodesic and explains the free fall qualitatively and quantitatively with only elementary algebra. [ABSTRACT FROM AUTHOR]

For a given physical duration, certain events can be experienced as subjectively longer than others, an illusion referred to as subjective time dilation. Many factors have been shown to lead to this illusion in perceived duration, including low-level visual properties of the stimulus (e.g., increase in motion, brightness, and flicker), an unexpected stimulus in a sequence of events, as well as affective factors. Here we report the results of two experiments in which we tested for the influence of scene and object knowledge on subjective time dilation. Based on the results of earlier studies, we predicted that visual scenes and objects containing semantic violations would be judged as lasting longer than control stimuli. The findings from both experiments indicate that stimuli containing semantic violations were judged to be present for longer than stimuli without semantic violations. We interpret our results to mean that neural processes that encode for perception of duration can operate on conceptually integrated scene and object representations. We further conjecture that the underlying neural code for duration perception is likely correlated with the amplitude of neural activity expended on the processing of incoming sensory information. [ABSTRACT FROM AUTHOR]

The precision of optical atomic clocks is approaching a regime where they resolve gravitational time dilation on smaller scales than their own extensions. Hence, an accurate description of quantum clocks has to take their spatial extension into account. In this article, as a first step toward a fully relativistic description of extended quantum clocks, we investigate a quantized version of Einstein's light clock fixed at a constant distance from a large massive object like the Earth. The model consists of a quantum light field in a one-dimensional cavity in Schwarzschild spacetime, where the distance between the mirrors is fixed by a rigid rod. By comparing a vertical and a horizontal clock, we propose an operational way to define the clock time when the clock resolves gravitational time dilation on scales smaller than its extension. In particular, we show that the time measured by the vertical light clock is equivalent to the proper time defined at its center. We also derive fundamental bounds on the precision of these clocks for measurements of proper time and the Schwarzschild radius. [ABSTRACT FROM AUTHOR]

Human timing and interoception are closely coupled. Thus, temporal illusions like, for example, emotion-induced time dilation, are profoundly affected by interoceptive processes. Emotion-induced time dilation refers to the effect when emotion, especially in the arousal dimension, leads to the systematic overestimation of intervals. The close relation to interoception became evident in previous studies which showed increased time dilation when participants focused on interoceptive signals. In the present study we show that individuals with particularly high interoceptive accuracy are able to shield their timing functions to some degree from interference by arousal. Participants performed a temporal bisection task with low-arousal and high-arousal stimuli, and subsequently reported their interoceptive accuracy via a questionnaire. A substantial arousal-induced time dilation effect was observed, which was negatively correlated with participants' interoceptive accuracy. Our findings support a pivotal role of interoception in temporal illusions, and are discussed in relation to neuropsychological accounts of interoception. [ABSTRACT FROM AUTHOR]

This article is devoted to the criticism of the wave-particle dualism and the provisions of the special theory of relativity (SRT). The fallacy of accepting the extended principle of relativity and identifying particles and waves is shown. The substantiation is given that the own fields of physical objects, which are material substances and spatially connect physical objects with each other, are the medium of propagation of light waves. The causal and visual picture of the propagation of light waves is considered, and the features of the mechanism of their propagation in comparison with other types of waves are described. On the basis of an alternative method for obtaining the relativistic law of velocities addition, the inconsistency of the principle of invariance of the interval adopted in the framework of SRT is shown. The inconsistency of the SRT positions and conclusions regarding the so-called relativistic effects-time dilation, mass increase, length decrease, as well as the energy of relativistic particles is shown. The presence of the clock paradox is shown by a simple example. The conclusion is made about the incorrectness of using mathematical transformations of Lorentz and the four-dimensional continuum in the physical representation. [ABSTRACT FROM AUTHOR]

Recent research has indicated that attractive faces often cause a dilation of our time perception thus affecting physical and mental health, and speculates that this could be relevant to the fact that attractive faces capture people's attention. Nevertheless, there was no direct experimental data to support this speculation. The present work was designed to illustrate how attention affects time perception of facial attractiveness. It utilized two experiments to investigate this phenomenon. In Experiment 1, perception of timing and attention bias were assessed using a temporal reproduction task and a dot‐probe task. Increased attention bias was found to mediate the time dilation effect of facial attractiveness. Experiment 2 adopted dual‐task paradigm, combining a temporal reproduction task and attractiveness rating task, to manipulate attention allocation. The findings suggested that allocating more attention to the task requiring timing enhanced the time dilation effect caused by the faces. Results of Experiments 1 and 2 converge to show that attention plays an essential role in the effects of facial attractiveness on time perception. [ABSTRACT FROM AUTHOR]

This paper examines the possibility of controlling the outcome of measured (flat space-time) relativistic effects, such as time dilation or length contractions, using pure rotations and their nontrivial interactions with Lorentz boosts in the isometry group SO + (3 , 1) . In particular, boost contributions may annihilate leaving only a geometric phase (Wigner rotation), which we see in the complex solutions of the generalized Euler decomposition problem in R 3 . We consider numerical examples involving specific matrix factorizations, along with possible applications in special relativity, electrodynamics and quantum scattering. For clearer interpretation and simplified calculations we use a convenient projective biquaternion parametrization which emphasizes the geometric phases and for a large class of problems allows for closed-form solutions in terms of only rational functions. [ABSTRACT FROM AUTHOR]

Perception of time is not always veridical; rather, it is subjected to distortions. One such compelling distortion is that the duration of regularly spaced intervals is often overestimated. One account suggests that excitatory phases of neural entrainment concomitant with such stimuli play a major role. However, assessing the correlation between the power of entrained oscillations and time dilation has yielded inconclusive results. In this study, we evaluated whether phase characteristics of neural oscillations impact time dilation. For this purpose, we entrained 10‐Hz oscillations and experimentally manipulated the presentation of flickers so that they were presented either in‐phase or out‐of‐phase relative to the established rhythm. Simultaneous electroencephalography (EEG) recordings confirmed that in‐phase and out‐of‐phase flickers had landed on different inhibitory phases of high‐amplitude alpha oscillations. Moreover, to control for confounding factors of expectancy and masking, we created two additional conditions. Results, supplemented by the Bayesian analysis, indicated that the phase of entrained visual alpha oscillation does not differentially affect flicker‐induced time dilation. Repeating the same experiment with regularly spaced auditory stimuli replicated the null findings. Moreover, we found a robust enhancement of precision for the reproduction of flickers relative to static stimuli that were partially supported by entrainment models. We discussed our results within the framework of neural oscillations and time‐perception models, suggesting that inhibitory cycles of visual alpha may have little relevance to the overestimation of regularly spaced intervals. Moreover, based on our findings, we proposed that temporal oscillators, assumed in entrainment models, may act independently of excitatory phases in the brain's lower level sensory areas. [ABSTRACT FROM AUTHOR]

Three experiments are reviewed, performed (in 2014–2016) at ID18 of ESRF to measure the influence of acceleration on time dilation by measuring the relative shift between the absorption lines of two states of the same rotating absorber with accelerations anti‐parallel and parallel to the incident beam. Statistically significant data for rotation frequencies up to 510 Hz in both directions of rotation were collected. For each run with high rotation, a stable statistically significant 'vibration‐free' relative shift between the absorption lines of the two states was measured. This may indicate the influence of acceleration on time dilation. However, the measured relative shift was also affected by the use of a slit necessary to focus the beam to the axis of rotation to a focal spot of sub‐micrometre size. The introduction of the slit broke the symmetry in the absorption lines due to the nuclear lighthouse effect and affected the measured relative shift, preventing to claim conclusively the influence of acceleration on time dilation. Assuming that this loss of symmetry is of first order, the zero value of the relative shift, corrected for this loss, falls always within the experimental error limits, as predicted by Einstein's clock hypothesis. The requirements and an indispensable plan for a conclusive experiment, once the improved technology becomes available, is presented. This will be useful to future experimentalists wishing to pursue this experiment or a related rotor experiment involving a Mössbauer absorber and a synchrotron Mössbauer source. An indispensable plan, requirements and challenges to overcome for a conclusive experiment to test time dilation due to acceleration, based on three experiments at ESRF, is presented. [ABSTRACT FROM AUTHOR]

Abstract Background A recent meta-analysis left open a significant question regarding altered time perception in depression: Why do depressed people overproduce short durations and under-produce longer durations if their present experience is that time flows slowly? Experience and judgement of time do not seem to accord with one another. Analysis By excluding two of the six studies on methodological grounds from a previous meta-analysis of medium-length interval productions, and re-analysing the remaining four studies, the present paper finds that subjective time accelerates from initial dilation within present experience (approximately 1 s duration) to subsequent acceleration within working memory (approximately 30 s duration) when depressed. Proposals It is proposed that depressive time dilation and acceleration refer to the default mode and central executive networks, respectively. The acceleration effect is suggested to occur due to mood congruency between long intervals, boredom, and depression. This mood congruency leads to the automatic recall of intrusive, negative, and non-specific autobiographical long-term memories used to judge intervals from previous experience. Acceleration in working memory then occurs according to the contextual change model of duration estimation. Limitations The meta-analysis is limited to four studies only, but provides a potential link between time experience and judgement within the same explanatory model. Conclusions Similarities between psychological time dilation/acceleration and physical time dilation/acceleration are discussed. Highlights • Meta-analysis of time experience and judgement when depressed is contradictory. • Experience is dilated at short intervals but longer intervals seem to accelerate. • This paper explains the acceleration effect via working memory processes. • Time experience and judgement can then be explained by the same theoretical model. • Relativistic acceleration of psychological and physical time is also discussed. [ABSTRACT FROM AUTHOR]

This article describes the analytical estimation of time dilation along the elliptical orbit of a satellite due to effects of relativity where the functioning has been time-dependent. The satellites in circular orbit are calibrated as moving frame of reference at constant velocity in constant non inertial frame of reference, namely Global Positioning System satellites where effects of both relativistic and gravitational time dilations can be seen. This article deals with the variation of the time dilation along the elliptical orbit whose speed of reference frame varies with respect to time and also varying the non-inertial frame of reference. The relativistic effects on the time dilation, is caused by the Earth rotation, due to the orbit eccentricity. The estimated values have a scope in the field of space mechanics. As a result the plot has been intended along the orbit comparing to circular orbit in both special and general relativity perspective. [ABSTRACT FROM AUTHOR]