Dilation Definition and 1000 Threads

How can speed of light be absolute yet that fact and relativity of sublight speed implies relativity of space and time intervals; if time time dilation is infinite at v=c, then time stands still only from that reference frame, but light takes a longer time relative to any other reference frame...

Homework Statement A rocket ship carrying passengers blasts off to go from New York to Los Angeles, a distance of about 5000 km. (a) How fast must the rocket ship go to have its own length shortened by 1%? (b) Ignore effects of general relativity and determine how much time the rocket...

Homework Statement It is not an official question but a request for pointers. I am trying to derive the Lorentz time equation to understand the intuition behind it. My math skills are not very good so it might be an obvious question for you. Please see below for my attempt. The variables are...

Hello, Firstly, let me point out that I do not have much knowledge in physics. However, after reading a certain book, I wanted to find out more about time dilation. I spent a few days reading about it. Here is the problem: Homework Statement I would like to be able to calculate the...

I was wondering about how to speed up time because I was bored, so I considered rotating my body clockwise (in the northern hemisphere) in order to speed up the rotation of the Earth by creating angular momentum opposite to that of the earth. I was thinking that this would then speed up the...

Do you know if there are experiments on particles having interacted which illustrate the Neumark dilation theorem?

Can anyone explain how the time dilation formula works? T=t/(√(1-v^2)/c^2))... ... What does the 1 stand for? Why include it? Can you write down the process of the formula?... How does ((C*t)^2))/c^2-v^2 lead to the time dilation formula? Please explain the process.

In mathematics, what is the name (type) for a curve given by velocity and time dilation? Specifically, I want to find a name for the curve y=1/(1-x^2)^{1/2} This curve is derived from the equation of a unit circle (x-a)^2+(y-b)^2=r^2 where y=(1-x^2)^{1/2}

when muons are created in the atmosphere and fall to Earth the Earth clock runs faster. Thus, the "slower" muon clock allows more of them to reach the Earth's surface. But from the muons' perspective, the Earth is moving towards the muon. Shouldn't the muon's clock run "faster" and there should...

I want to write a science-fiction story concerning the rapid increase in technology affecting the speed at which spacecraft travel and passengers age (relative to each other). Theoretically, would it be possible that a son leaves a certain time (a number of years) before his father to...

Do experiments like 1971's Hafele & Keating show that SR relativistic effects of time dilation are not mere products of measuring symmetry? Does such an experiment show that for the jets it is their clock that has kinematic time dilation in relation to the other clock that 'remains'...

Definition/Summary Time dilation is the factor by which an inertial observer measures another observer's clock as going slow. Time dilation is composed of two factors: 1) a relative factor of \sqrt{1\ -\ v^2/c^2} for Lorentz time dilation, which depends only on the velocity of the clock...

We measure time based off of atomic vibrations, so time dilation from gravity and velocity are nothing more than pressure applied to the atoms, slowing their vibrations. This isn't an accurate measure of what we consider time, but more of a measure of the reaction of atomic vibrations under...

If velocity is relative and if we cannot say which is moving away from what *objectivley, how do we say that time dilation is relative as well if we can tell who experienced the time dilation, as special relativity shows - and other experiments (muon concentrations etc). For example the jets...

Hello Forum, An event is a point in spacetime with spatial coordinates and a time coordinate: (x,y,z,t). An event does not have a duration since it only lasts for an instant t. We can talk about time duration to mean the temporal separation between two different events, correct? In the...

Homework Statement A baseball player at home plate hits a pop fly straight up (the beginning event) that is caught by the catcher at home plate (the ending event). Which one or more of the following obeservers record(s) the proper time interval between the two events? (a) A spectator sitting...

Hello Everyone, I am new to this forum. I understood from sources that space-time is like a fabric. The massive bodies bend the space around it, hence the gravity. If time is 4rth dimension, so, the space is bent in time due to mass. that pretty much explains stopping of time in black holes as...

I am trying to get an understanding of general relativity one tidbit at a time. I have a vague concept of why curved spacetime causes the effect we call gravity. However, there's an aspect of it (ok, there' are quite many aspects of it, but I'm concentrating on this one right now) that I can't...

I was browsing through old threads and a user named universal_101 kept asking about why we can use muons as a direct measurement of time dilation but only an indirect measurement of length contraction. It was pointed out that the two go together and cannot be separated, but it got me thinking...

Picture: - - - ---------------------------------- p -> ---------------------------------- + + + Positively charged particle "p" is initially moving to the right between two capacitor plates. Is the...

Homework Statement A spaceship has traveled for 14 years at an average speed of 90% of the speed of light. Its round trip from Earth has taken 14 years according to clocks on the ship. (a) How long has the journey taken according to Earth clocks? Homework Equations t = t’ / (1-v2/c2)-1/2The...

Out of interest I'm studying a book "A first course in general relativity" which is a great book in my opinion because it explains the subject very well. I'm a beginner though and I have a hard time understanding one particular thing mentioned quite early in the book. I'm attaching a scan of a...

Black hole A moves at slow velocity, and there's an Einstein light clock hovering near the event horizon. Black hole B moves at high velocity, and there's an Einstein light clock hovering near the event horizon. The black holes are identical. And the light clocks are at the same...

I will just describe a common thought experiment to do with special relativity and a question I have about it. Note this question only applies to the realms of SPECIAL relativity. Imagine a scenario in which there are 2 spaceships A and B. Each spaceship has its own clock. Spaceship B moves...

Hi people, please could someone enlighten me on gravitational time dilation. I have read online that some places, such as neutrons stars, warp time so much that time can pass 100 times slower than it does on Earth. I was just thinking about a human heart beating. If a healthy heart rate on Earth...

I am trying to get another insight in what I think is currently for me a contradiction. I have searched the forums, and the web but come to the following assertion: The coordinate distance is the computation of the proper distance times the gamma-factor, while the "coordinate" length is a...

Hello Physics Forums! I'll try to cut right to the chase. I'm studying both length contraction and time dilation in my physics class and it seems these two occurrences are mutually exclusive. That is, in any given situation, only time will be dilated or length will be contracted. This doesn't...

Since many authors call simultaneity between events a convention, and that under the specific set of rules we may choose a convention or a coordinate system relative to an IRF (or non-inertial) to describe space time, I wonder what's the relation between this and the effects of length...

This has bothered me for a long time. I understand that time varies with velocity relative to the observer. But what about this case -- Suppose we have 3 space ships: A, B, and C. They are spaced widely apart with B in the middle and A and C at opposite sides to B. A and C are moving towards...

So, I am learning about atomic clocks. I went to this website: http://tycho.usno.navy.mil/simpletime.html And I started watching the atomic clock on that website tick away. It was ok and cool. At the moment, the website is frozen with "Loading..." for each time zone. When I started...

Lets say we have a couple objects, one very close to a black hole, one a little farther out and then one a good distance away. Would the one very close to the black hole see the other ones time moving much quicker than their own time? How about just as they are going to hit the event horizon...

So basically, my physics class has begun focusing on SR. And i just wanted to clarify something. I have been referencing: http://physics.mq.edu.au/~jcresser/Phys378/LectureNotes/SpecialRelativityNotes.pdf On page 23, it states "A clock will be observed to run at its fastest when it is...

The three main effects of SR occur in inertial frames and change the description of space-time relative to a particular observer. My question here is how do these effects occur on Earth, since we know that motion on Earth is non-inertial. I know that we travel at small speeds and that we can't...

I just watched a video that kind of warped my understanding of time dilation. It said that not only would time appear slow from the point of view of someone standing still looking into something going near the speed of light but if you were going near the speed of light things that are...

As I've red, different points on the rotating disk, or rotating object have different velocities and so they should time dilate differently. Points on equator are for instance quicker than those in Scandinavia. When we take an inertial frame that has zero velocity with respect to the Earth as a...

The title says it all, really. Are we able to describe GR in terms of a Graded Time Dilation Field in Euclidean space? From http://cpl.iphy.ac.cn/EN/Y2008/V25/I5/1571 we can see that light curvature can be analogously described via a material with a graded index refraction, so my question is...

I know how to derive the lorentz time dilation equation. I am wondering how to derive the equation for gravitational time dilation: T=To(1/(sqrt(1-(2GM)/(Rc2)))

Homework Statement An Ω- particle has rest energy 1672 MeV and mean lifetime 8.2*1011 s. It is created and decays in a particle track detector and leaves a track 24 mm long. What is the total energy of the  particle? Homework Equations E=\frac{mc^2}{\sqrt{1-(\frac{v}{c})^2}}...

Hi all, I tried searching for this but failed to find an answer to my question. I am having an issue with properly interpreting the equations for time dilation and length contraction. Let's assume that I am standing still and a train is passing by next to me (moving with uniform velocity). Let...

It seems that time dilation does not occur due to acceleration alone. It surprised me to learn this due to the equivalence principle as I was under the impression that one could not experimentally know the difference between being accelerated in space and being at rest in a gravitational field...

Hello, It is my understanding that in the case of two observers (A and B) passing each other at high speeds that due to time dilation observer A would be moving in slow motion with respect to observer B, whereas observer B would be moving in slow motion relative to observer A (i.e. each...

I am currently taking an undergraduate modern physics course that offers a brief overview of relativity. Let us consider a scenario where we have one clock on Earth in a rest frame, and one clock traveling in space at a constant speed v. we have some sort of mechanism for viewing the traveling...

I'm only an amateur enthusiast when it comes to physics and have no background in science at all. It's just something I enjoy thinking about. One thing I am really finding difficult to get my head around is how time dilation works. So I've put a thought experiment below and would appreciate it...

There are only two frame moving relative with each other at certain velocity. One frame see the other going right and the other to the left. Isn't it contradict that each see the other time running slow and both are correct? And this isn't the case , where one twin leave Earth and each see...

The popular thought experiment states, that if of two identical twins one is left on Earth an the other is embarked on a spaceship and sent into open space at near-c velocity, time for the traveling one will pass slower than for the one left on earth, due to the speed. On the other hand, time...

The proper mean lifetime of ##\pi## mesons(pion) is ##2.6x10^{-8}s##. Suppose a beam of such particles has a speed of .9c. a) What would their mean life be as measured in the lab? b) How far would they travel(on average)before they decay? c)What would your answer be to part (b) if you...

I had a quick question about Time Dilation and Length Contraction. Are the two just different ways of measuring/describing the same effect? Or rather they both follow as a consequence from one another? i.e. I can find how much a length is contracted by finding the dilated time interval and...

Hi, could anyone help me out? The FLRW metric in spherical coordinates is: \;\; ds2 = dt2 - a(t)2(dr2 + r2dΩ2) \;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\; (1) I am considering a similar metric of the format: \;\; ds2 = \frac{1}{a(t')^{2}}dt'2 - a(t')2(dr2 + r2dΩ2)...

Disclaimer: I have no formal education in physics. I watched a TedTalk http://www.tedxamsterdam.com/video-wubbo-ockels-on-time-and-gravity/ and it got me thinking. Dangerous, I know. As I understand both velocity and gravity have an effect on our perception of time. How much does our...

I'm about to ask derivation of dilation time in terms of Special Relativity. I saw explanations in Introduction to Classical Mechanics by David Morin that dilation time is formed by assumption that light speed is absolute refers to all inertial reference. He derived it by comparing 2...