Dilation Definition and 1000 Threads

hi all I was thinking abt the time dilation derivation thought experiment a flash of light shone on a mirror(imagine a window on the left and motion of vehicle towards right), transverse to the direction of motion.according to the derivation the person in the rest frame,P would see the light...

At an origin there is an observer (A) who fires a laser at a series of beacons in a straight line spaced 186,000 miles (1 light second) apart each. At the same time as the laser is fired, a second observer (B) starts traveling on a path perpendicular to that of the laser, stopping and...

From https://www.physicsforums.com/showthread.php?t=40391 in gravitational time dilation. At the center of neutron star PSR J1614-2230 at 1.97 SM mass of Sun 1.9891×10^30 kg mass of PSR J1614-2230. 4 ×10^30 gravitational constant = 6.67300 × 10-11 m3 kg-1 s-2 radius(rough estimate) =...

I recently read that the center of a quasar does not or almost doesn't experience time dilation, can anybody help me understand this more? The text didn't help much.

Suppose, there are two inertial frame first is in motion with constant speed and second is motionless. We can say that two frames are relatively in motion with each other with constant speed. So time would slowdown for each frame referenced by other frame. But after some long journey first frame...

I (think I) understand that: 1. With the Schwarzschild metric, the ratio of proper time to coordinate time decreases ("clock runs slower") with decreasing radial distance. (And ratio of proper distance to coordinate distance increases.) 2. The geodesic path followed by a freely falling...

While gravitational redshift refers to what is seen, gravitational time dilation refers to what is deduced to be "really" happening once observational effects are taken into account. When using special relativity's relativistic Doppler relationships to calculate the change in energy and...

If one wants to calculate the elapsed time from the perspective of an object A moving at velocity, v, for time, t, relative to a stationary object B, all you have to do is calculate: \int_{t_o}^{t_f}\frac{t}{\gamma} Of course, \gamma has no dependence on t because v is constant, so we get...

Homework Statement In which of the following situations is the time interval between the two events in one frame equal to (LORENZ FACTOR (special y symbol)) multiplied by the time interval in the other frame. explain briefly. a) A muon is created (event #1) high in Earth's atmosphere and...

Homework Statement Concicer the dilation operator D = \vec{r} * \vec{p} Compute [D,\vec{r} ] and [D, \vec{p}] Homework Equations p = - i * hbar The Attempt at a Solution I think the question is really if [D, \vec{r}] commutes I got this: D = \vec{r} * \vec{p}...

Homework Statement The nearest star to Earth is Proxima Centauri, 4.3 light-years away. At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 3.7 years, as measured by travelers on the spacecraft ? How long does the trip take according to Earth...

Here's a scenario: A crew travels through the Universe in a spaceship capable of 100% light speed. Relativity states that anyone inside of said craft will experience time dilation, possibly to the point of time coming to a complete stop for the crew/passengers. But time passes much quicker...

I have been wondering this ever since I was in elementary school and I am hoping for an answer. The time dilation equation for general relativity is time dilation=e^(gh/(c^2)). This applies to any object that has mass, and I am wondering if it also applies to the Big Bang (which has mass). I...

I have some questions about time dilation I not really understand to come further (and I find it all very interesting). 1) I understand that the situation between A (standing still) and (moving) B is SRT symmetric, so if they compare clocks they both see the same time. In fact there is no...

Hi, I've been listening to a Professor Jim Al-Khalil's scipod on time travel. I think this guy is bloody excellent by the way. http://reader.mac.com/mobile/v1/http%3A%2F%2Fwww.jimal-khalili.com%2Fpodcast%2Fjim.rss Anyway, He said to an observer on the Earth a clock on a...

As I currently understand it from the point of view of an observer falling into a black hole it takes a finite time to cross the event horizon and reach the singularity. From the point of view of a far away observer the person falling into the black hole never actually crosses the event horizon...

Special relativity homework question time dilation 1. Homework Statement You are a passenger on a brand-new spaceship that travels at 95% of the speed of light, i.e., v = 0.95 × c. The spaceship is bound for the star, Altair, at a distance of 17 light years from Earth. If the spaceship...

Homework Statement You are a passenger on a brand-new spaceship that travels at 95% of the speed of light, i.e., v = 0.95 × c. The spaceship is bound for the star, Altair, at a distance of 17 light years from Earth. If the spaceship departs on your 21st birthday, at a speed of v = 0.95c, how...

Thought experiment: Say for instance that a Baseball game is being played out on a planet that is orbiting the outer edge of a black hole. You, from deep in space away from any gravitational source, are watching this game from a powerful telescope. The batter comes up to bat; the pitcher...

So, according to my understanding, if we leave Earth and travel close to speed of light and then come back we may have time dilation (there will be one year for us, but 10 years for the people on Earth). But how does this work as long as there is no frame of reference? Why can't we consider...

For instance you have time dilation in special relativity which is said to be due to something moving faster than something else relative to it. You also have the time dilation in GR where time speeds up the further away you go from a body such as the Sun, Earth, etc. Now could it really...

My idea of explaining time dilation to others (average people) was : see a light wave as the time, person A standing still sees the time (light wave) passing, person B moving sees lesser time passing when going in the direction of the light wave (while "looking" to the light wave) because he is...

Does relativity theory make a connection between gravitational time dilation, and the time dilation experienced at high velocity?

A clock falling towards the event horizon of a black hole would appear slowed down to the point of being frozen in time (or almost). But I'd like to understand properly what happens to the length contraction experienced by an observer falling together with that clock. Would he experience...

I just had a quick question on time dilation that I'm stumped on. There are three observers: two are traveling on separate ships traveling close to the speed of light (their speeds are the same) in opposite directions parallel to each other. One observer is standing still on a space station...

As far as I understand, time dilation corresponding to redshift has been confirmed for distant supernova. However, galaxies are being detected only 480 million years after the bigbang at redshifts of around 10 or more. Does this mean they took less than 45 million years to form in real time?

https://www.physicsforums.com/showthread.php?p=3577768#post3577768" has caused me to question my assumptions. If a target of observation is moving at relativistic velocities but its distance does not change wrt the observer, is it observed to be experiencing time dilation? Alice stands at...

Suppose there are two observers separated by distance of 2 light minutes. They have 2 identical clocks, which are synchronized. Suppose one of the observer shoots a missile at 3 PM. The other observer, who is able to see him, will observe that the missile has been shot at 3.02 PM. According to...

I propose an explanation of the special relativistic time dilation and calculation of its factor in terms of the difference in observational times for incoming and receding objects, based on the following thought experiment: Imagine a spaceship coming from planet X to Earth with velocity V...

Sorry for yet another time dilation question. I have a couple example problems that I can't seem to explain. 1) A ship leaves the Sun and heads for Earth at 0.5c. An observer on Earth would see the the light from the sun take 8 min, and the ship take 16 min. The pilot's clock would show it...

I'm working on a simple time dilation problem: Astronomers discover a planet orbiting around a star similar to our sun that is 20 LY away. How fast must a rocket ship go if the round trip is to take no longer than 40 years in time for the astronauts aboard? I have set up the problem: T=...

As time-dilation is stated in STR, 1.) it is an intrinsic decrease in rate of passing of time, with relative motion(radioactivity half-life change). 2.) it is non-directional, that is, time-dilation depends only on the magnitude of relative speed. Now, please consider the following...

Hi! :smile: Need some help here. Can we perceive time dilation and length contraction in a non-inertial reference frame? If we observe a reference frame experiencing acceleration close to c, do we see the same effects as in an inertial reference frame?

Homework Statement Plans are made to send a spaceship from Earth to a nearby star 10 light-years away and at rest with respect to Earth. The light support systems within the spacecraft will last for a year. (a) what is the minimum speed of the spacecraft relative to the Earth-star system if...

After a fairly long time of thinking I had a decent grip on the concept of time dilation, it has suddenly occurred to me that I don't. My issue is with the concept of the aging twins thought experiment (or whatever it's called) where if one shoots off at some comparable speed to the speed of...

Relative some arbitrary point in Earth’s orbit around the Sun, does Earth experience varying degrees of time dilation specifically from gravity? With Earth's orbit around the sun being elliptical I wondered if Earth experiences varying degrees of time dilation caused by the suns gravity (or...

Homework Statement Anna is on a railroad flatcar moving at 0.6c relative to Bob. Her arm is outstretched in the dirction the flatcar moves, and in her hand is a flashbulb. According to her wristwatch, the bulb goes off at 100 ns. This even according to Bob differs by 27 ns. a) is it earlier...

For the universe to be totally flat, and not just asymptotically closer to being flat as the universe expands, wouldn't there have to be pockets of hyperbolically-curved spacetime? In either case, I still would like to know how one expresses time dilation and length contraction in hyperbolic...

So, I am having trouble understanding how time dilation and length contraction in special relativity merge together and describe space-time. I guess the best way to ask this question is to pose a question, which i know how to answer mathematically, but I would like to discuss some thoughts about...

Can anyone tell me What is the relationship between the orbital radius of a satellite and the time gained per second due to its weaker gravity at its altitude? In relation to that how much time does the International Space station lose per-second due to weaker gravity at its altitude? Also...

Hey there guys I just have a question to ask some of you. Given the occurence of time dilation being related to an objects state of motion I have an interesting thought. This is a very general question, my teacher only briefly covered this topic in class as it's not part of our course but it...

In special relativity we have the velocity 'u', being the difference in speed between two objects, from which we work out time dilation, length contraction etc. But if those objects are separated by some expanding space, but not moving with respect to that space, is there still the dilation...

Hello all. Not sure if this is the right place for this question, or if it even makes sense. This is my first post since registering a week ago, however I have been lurking and reading on here for a while. Great site! Lots of good information on here. Anyways, I have been thinking about...

As mass approaches C it also approaches infinite mass. As it acquires mass, does it also accumulate gravitational forces? I believe this is important when considering the conservation of angular momentum of mass as it spirals towards a Black Hole.

An athlete has learned enough physics to know that if he measures from the Earth a time interval on a moving spacecraft , what he finds will be greater than what somebody on the spacecraft would measure. He therefore proposes to set a world record for the 100m dash by having his time taken by...

moving closer to light speed relative to another clock tick slower? I understand that the waves take longer to reach the stationary observer on the turn around, but that's just appearance. It still seems the clocks would be in sync upon the return. What is making time actually slow down...

Time Dilation --- Help needed Homework Statement Time dilation says, " Moving clocks run slow". Homework Equations The Attempt at a Solution For example, a stationary clock shows 4 PM and at the same 4 PM a spacecraft moves with a clock inside it showing the same 4 PM. Now after...

I only know time dilation in it's basic form and it was explained to me beautifully using mirrors in a spacecraft . The light would go vertically, taking longer if you were at a stationary frame looking into the spacecraft . This all made sense to me; however, what would happen if the mirrors...

2 space stations are separated by a distance of 10 light years and are at rest wrt each other. I set off from A to B at a constant velocity of 0.5c. As I understand it, 20 years would pass for people on the space station but when I arrived at the second station I would have only aged about...

Further to the other current thread, I have a different 'don't understand' issue for time dilation. I've thought it over and I might have a slight grasp of 'the answer', but it is still a bit murky for me: Two space ships of the future pass each other in opposite directions, each traveling at...