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This article from Discover explores the concept of time and whether it will ever come to an end. The author explains that time always moves forward, from the past to the future, and that it can slow down but never stop. The theory of special relativity by Einstein suggests that the faster an object moves through space, the slower it moves through time. However, this time dilation is only observed by outside observers, not by the person experiencing it. The article also mentions that it is theoretically possible to skip forward into the future by traveling at high speeds. Ultimately, the author concludes that time will not come to an end in the future, as the universe continues to expand. [Extracted from the article]

Editor's pick Caution required when tinkering with plant diet 8 July, p 17 From Matthew Stevens, Sydney, Australia While the gradual shift to a more sustainable, plant-based diet globally is a good thing, I feel some concern at the news that UK company Moolec has created soya beans with 25 per cent pig protein. In this view, a sufficiently complex brain is necessary, but not sufficient, for consciousness to arise, and if that is so, we need have no worries about even much larger lab-grown brains that need constant supervision to stay alive. Grounds to say lab-grown brains aren't conscious Letters, 24 June From James Whalley, Hinchinbrooke, Quebec, Canada Eric Kvaalen says that if consciousness arises out of brains, we should stop experiments on lab-grown organoids. [Extracted from the article]

Even if these effects make it impossible for ring wormholes to exist, their relative simplicity compared with regular wormholes means studying them could help us understand these quantum wrinkles better, or why time travel seems to be off-limits in our universe, says Wiseman. WORMHOLES are often thought of as tunnels through space-time with black holes for entrances, but they could theoretically be flat instead, like a door into another location, another universe or the past. [Extracted from the article]

From one former Olds diesel owner to another, I think you might be a car guy - Ed. Car and Driver issues may be getting thinner and less frequent, but every article was car-oriented. His well-crafted tale is a great memorial to the late P.J. O'Rourke, whose Car and Driver pieces were treasures. Typically, the delta between us is 0.5 second or less, with the assigned driver being quicker due to more familiarity with the car in question - Ed. [Extracted from the article]

AN INTERVIEW WITH PHYSICIST JUN YE ON ATOMIC CLOCKS, TIME DILATION AND TESTING THE LIMITS OF RELATIVITY [ABSTRACT FROM AUTHOR]

News News & Technology Physics WORMHOLES are often thought of as tunnels throughspace-time with black holes for entrances, but they couldtheoretically be flat instead, like a door into another location,another universe or the past. These "ring wormholes" would be made up of a string ofexotic matter with negative energy -- a property that ispossible due to quantum effects, but only, as far as we know,in extremely small amounts. [Extracted from the article]

But if the shower is a "horizontal" one, coming from the direction of the Tibetan Plateau mountains, it cannot be due to an incoming cosmic-ray particle or a high-energy gamma ray: Charged particles and photons are not able to penetrate kilometers of rock. "But we expect that ultra-high-energy cosmic rays are accompanied by extremely energetic neutrinos", says GRAND project manager Charles Timmermans (Radboud University, the Netherlands), "and because neutrinos have no electrical charge, they point back to their source." Just like the new radio antennas of Pierre Auger, GRAND will also detect air showers produced by cosmic-ray particles, but its ultimate goal is to hunt for extremely energetic neutrinos. Instead, the culprit must be a neutrino, and at least some of the highest-energy neutrinos are expected to be generated in the same extragalactic sources that also produce ultra-high-energy cosmic rays. [Extracted from the article]

A few years ago, I had a car crash. James also suggested that new experiences, such as foreign travel, have a similar time-expanding effect. If there was an association between information processing and time perception in these experiences, then the degree of information processing would also have to increase very significantly. Significantly, similar degrees of dramatic time expansion were reported in altered states of consciousness, such as drug experiences and spiritual experiences. [Extracted from the article]

The article focuses on the construction of time machines, which are machines that allow human travel through time. Topics include the use of wormholes in time travel, the theory of relativity, and human understanding of space and time. Information is provided on the time dilation effect and human perception of time flow.

The article focuses on the twin paradox, which describes the time dilation of humans in speed of light travel. Topics include human perception of time flow, the slowing of time due to motion, and if time is relative. Information is provided on time acceleration, theories on time and space, and time travel's effect on humans.

We consider Aumann's famous result on “agreeing to disagree” in the context of imprecise probabilities. Our primary aim is to reveal a connection between the possibility of agreeing to disagree and the interesting and anomalous phenomenon known as dilation. For such a purpose it is convenient to use Geanakoplos and Polemarchakis' communication setting, where agents repeatedly announce and update credences until no new information is conveyed by the announcements. We show that for agents who share the same set of priors and update by conditioning on every prior, once the procedure of communicating credences stops, it is impossible to agree to disagree on the lower or upper probability of a hypothesis unless a certain dilation occurs. With some common topological assumptions, the result entails that it is impossible to agree not to have the same set of posterior probability values unless dilation is present. This result may be used to generate sufficient conditions for guaranteed full agreement for some important models of imprecise priors, and we illustrate the potential with an agreement result involving density ratio classes. We also provide a formulation of our results in terms of “dilation-averse” agents who ignore information about the value of a dilating partition but otherwise update by full Bayesian conditioning. [ABSTRACT FROM AUTHOR]

In this paper, the controllability problem is addressed for temporally switching networks and the associated temporally switching systems. The state controllability criterion of temporally switching systems is firstly obtained, which stands for structural controllability of temporally switching networks with the same structure. With a new temporal interpretation of the dilation and intersection concepts, some algebraic and graphic criteria are precisely derived. Specifically, it reveals that the essence for the structural controllability is the existence of $n$ temporally independent walks (the $n$-walk theory), which generalizes the classical concept of cactus in graph theory to temporal networks. Furthermore, from the perspective of the new $n$-walk theory, its uniqueness makes the notion of strong structural controllability more precise and clearer for temporal networks. This comprehension of the (strong) structural controllability concept not only is of particular advantage for more in-depth studies of network control problems, but also provides useful guidance for constructing controllable temporal networks. [ABSTRACT FROM PUBLISHER]

The article offers information on medical care provided to a pregnant women who underwent abortion at 28 weeks in Washington DC. It discusses the difference between the rhetoric of pro-choice activists who argue women choose abortion with full knowledge and autonomy and the reality on the ground in the clinic.

Film THE decline of Pixar can be charted with relative precision from its acquisition by Disney in 2006. The new Lightyear is, officially, the movie Andy loved, the franchise that produced the Lightyear toy and gave the plastic Buzz his confidence and brio. In the original Toy Story, Buzz (then voiced by Tim Allen) was presented as the main character in a space opera beloved by the pre-teen Andy, the owner of the movie's toys. [Extracted from the article]

This work presents a method for color texture analysis based on fractal geometry. The method is based on its predecessor [4] and consists of mapping each color channel onto a surface and dilating such surface by spheres with a variable radius. The descriptors are obtained from the relation between the volumes of the dilated surfaces and the dilation radii. The dilation process creates a mutual interference among the color channels. The proposed descriptors measure the degree of such interference as well as the complexity of pixel intensity arrangements. This combination provides a robust and precise texture description. The efficiency of the method is assessed in a classification task of well-known texture data sets and the results demonstrate that it outperforms the best approaches described in the literature. [ABSTRACT FROM AUTHOR]

GLO:nyo/27sep21:80n1.jpg PHOTO (COLOR): . gl Martyna Majok's Sanctuary City contains other romances, other yearnings. The CULTURE PAGES CRITICS Helen Shaw on Sanctuary City Angelica Jade Bastienon Y: The Last Man. Alison Willmore on The Eyes of TammyFaye. [Extracted from the article]

We propose an implementation of a twin-paradox scenario in superconducting circuits, with velocities as large as a few percent of the speed of light. Ultrafast modulation of the boundary conditions for the electromagnetic field in a microwave cavity simulates a clock moving at relativistic speeds. Since our cavity has a finite length, the setup allows us to investigate the role of clock size as well as interesting quantum effects on time dilation. In particular, our theoretical results show that the time dilation increases for larger cavity lengths and is shifted due to quantum particle creation. [ABSTRACT FROM AUTHOR]

The article discusses time dilation, focusing on physicist Albert Einstein's general theory of relativity and special theory of relativity. Topics include the effect of velocity and gravitational potential on time; the Hafele-Keating experiment on time dilation; and research at the National Institute of Standards and Technology (NIST) involving high-precision optical atomic clocks.

The article discusses the creation story in the book of Genesis from a scientific view. It argues that the creation of the universe was portrayed in six days for homiletic reasons, as a reminder to the Hebrew people of their obligation to rest and worship on the Sabbath. However, using Albert Einstein's theory of relativity, it also sought to reconcile how six calendar days of creation can be equal to the 15 billion years estimated age of the universe based on the concept of time dilation.

In order to solve the Tolman-Oppenheimer-Volkoff equations for neutron stars, one routinely uses the equations of state which are computed in the Minkowski spacetime. Using a first-principle approach, it is shown that the equations of state which are computed within the curved spacetime of the neutron stars include the effect of gravitational time dilation. It arises due to the radially varying interior metric over the length scale of the star and consequently it leads to a much higher mass limit. As an example, for a given set of parameters in a σ-ω model of nuclear matter, the maximum mass limit is shown to increase from 1.61 M⊙ to 2.24 M⊙ due to the inclusion of gravitational time dilation. [ABSTRACT FROM AUTHOR]

Atomic clocks can measure the gravitational redshift predicted by general relativity with great accuracy and for height differences as little as 1 cm. All existing experiments, however, involve the comparison of two independent clocks at different locations rather than a single clock in a delocalized quantum superposition. Here we present an interferometry scheme employing group-II-type atoms, such as Sr or Yb, capable of measuring the gravitational time dilation in a coherent superposition of atomic wave packets at two different heights. In contrast to other recent proposals, there is no need for pulses that can efficiently diffract both internal states. Instead, the scheme relies on very simple atom optics for which high diffraction efficiencies can be achieved with rather mild requirements on laser power. Furthermore, the effects of vibration noise are subtracted by employing a simultaneous Rb interferometer that acts as an inertial reference. Remarkably, the recently commissioned VLBAI facility in Hannover, a 10-m atomic fountain that can simultaneously operate Yb and Rb atoms and enables up to 2.8 s of free evolution time, meets all the requirements for a successful experimental implementation. [ABSTRACT FROM AUTHOR]

We obtain a remarkable semianalytic expression concerning the role of purely tidal curvature on accelerated probes, revealing some novel insights into the role of absolute vs tidal acceleration in the response of such probes. The key quantity we evaluate is the relation between geodesic (τgeod) and proper time (τacc) intervals between events on the probe trajectory. This is obtained as a covariant power series in curvature using a combination of analytical and numerical tools. A serendipitous observation then reveals that one can exactly sum all terms involving the purely tidal component ℰn=Rabcdϵabϵcd of curvature, with ϵab the binormal to the plane of motion, τgeod=.... For classical clocks, the above result represents an interesting closed form contribution of tidal curvature to the differential ageing of twins in the classic twin paradox. For quantum probes, it gives a thermal contribution to the detector response with a modified Unruh temperature, [kBT]ℰn=.... As an operational tool, the computational framework we present and the corresponding results should find applications to a wide range of physical problems that involve measurements and observations by use of accelerated probes in curved spacetimes. [ABSTRACT FROM AUTHOR]

We propose a novel probe of fundamental physics that involves the exploration of temporal correlations between the multi-frequency electromagnetic (EM) signal and the subthreshold GW signal or stochastic gravitational wave background (SGWB) originating from coalescing binaries. This method will be useful for the detection of EM counterparts associated with the subthreshold/SGWB signal. Exploiting the time delay between concomitant emission of the gravitational wave and EM signals enables inference of the redshifts of the contributing sources by studying the time delay dilation due to cosmological expansion, provided that the time-lag between the emission of gravitational wave signal and the EM signal acts like a standard clock. Measurement of the inevitable time-domain correlations between different frequencies of gravitational and EM waves, most notably in gamma-rays, will test several aspects of fundamental physics and gravitation theory, and enable a new pathway for current and future gravitational wave telescopes to study the universal nature of binary compact objects to high redshifts. [ABSTRACT FROM AUTHOR]

"I AM GLAD THAT I GOT RID OF THE MANUSCRIPT", Einstein wrote in late April 1925 to his wife, Elsa, "and thank you for doing me this favor of love." Einstein's theory, Gutfreund notes, is a hugely complex mathematical formulation of this simplesounding statement. PHOTO (COLOR): IN A NUTSHELL The equation above that Einstein hand-labeled "(53)" encapsulates his general theory of relativity. [Extracted from the article]

Planck scale modified dispersion relations are one way to capture the influence of quantum gravity on the propagation of fundamental point particles effectively. We derive the time dilation between an observer's or particle's proper time, given by a Finslerian length measure induced from a modified dispersion relation, and a reference laboratory time. To do so, the Finsler length measure for general first order perturbations of the general relativistic dispersion relation is constructed explicitly. From this we then derive the time dilation formula for the κ-Poincaré dispersion relation in several momentum space bases, as well as for modified dispersion relations considered in the context of string theory and loop quantum gravity. Most interestingly we find that the momentum Lorentz factor in the present and future colliders can, in principle, become large enough to constrain the Finsler realization of the κ-Poincaré dispersion relation in the bicrossproduct basis as well as a string theory inspired modified dispersion relation, at Planck scale sensitivity with the help of the muon's lifetime. [ABSTRACT FROM AUTHOR]

The article discusses that how ultrafast studies of chemical reactions and other molecular dynamics typically rely on the use of femtosecond.

The article discusses a joint paper published in the journal "Classical and Quantum Gravity" from the film "Interstellar"'s special effects team and scientific consultant Kip Thorne, on the team's decisions to modify real-life models of a black hole deemed to complex for audiences to understand. Topics include the visual effects studio Double Negative and director Christopher Nolan; and elements such as the black hole's accretion disk, spin, color scheme, time dilation, and Doppler shift.

The Wheeler equation, for electromagnetic disturbances in a gravitational field, was found by Fiziev to have exact solutions both above and below the event horizon, in the form of waves propagating both inwardly and outwardly. This observation can be interpreted and verified from the optical point of view, entirely on the basis of the Schwarzschild metric for length contraction and time dilation, in order to derive a differential version of Snell's law for the Schwarzschild black hole. It reveals interesting physics, including the correct amount of light deflection by the Sun, internal and external Oppenheimer-Snyder cones of the black hole, properties of its phonon sphere and the conclusion that light rays are kept below the horizon by length contraction and time dilation rather than deflection. [ABSTRACT FROM AUTHOR]

Recently, Takamoto et al. (2020) have discussed high precision measurements of gravity induced time dilation effects on optical lattice clocks located near the Earth surface. A relative tick frequency change, δν/ν0=(49 337.8±4.3)10-18, is found between two optical lattice clocks, one located at the ground floor, h=0 m, and the second one at an altitude hexp=452.596 m, on the Skytree tower in Tokyo. The results are compared with the predictions of Einstein's equivalence principle (EEP) estimated as an average over gravimeter measurements at h=0 m and h=450 m. We present a different derivation of the EEP prediction based on the calculation of the effective gravitational potential on the ground floor and at h=hexp, in excellent agreement with the value δν/ν0, providing an independent method to validate the differences in time dilation measured experimentally. In addition, we obtain the next-order correction to the present results, which may be tested in future more accurate experiments. [ABSTRACT FROM AUTHOR]

We study the tunneling probability of a massive (mw) uncharged scalar packet out from a near-extremal, static charged black hole (with mass M and charge Q≲M). We show that there is indeed a net probability that a massive uncharged particle tunnels out from the black hole so that the final state (with new mass M′≡M-mw

The article discusses the concept of time travel which was developed based on Albert Einstein's theory of special relativity. Topics include time dilation which refers to the relationship between space and time suggesting that time can move at different rates for different observers in different places, the implication of time dilation and the possibility of backward time travel which is more trickier.

The article presents questions and answers related to astronomy including how gas ejected during a supernova explosion would physically affect a person flying through it, the way National Aeronautics & Space Administration (NASA) is able to navigate Mars without a magnetic field, and time dilation.