Time dialation Definition and 74 Threads

Let's assume that we can build a kind of a perfect Faraday cage 1x1x1 meters, which contains today's cosmic background radiation with its peak wavelength and density. Radiation in the cage cannot escape from it, and the external radiation cannot penetrate it. Now let's mount the perfect clock in...

You know how people say that nothing can escape a black hole because gravity is faster than light at the event horizon? Well, I’m going to show that, in fact, you can’t even get to the event horizon. Time is slower near a black hole from an outside perspective, but from inside, time actually...

hello, I am interested in the speed of light as well as electromagnetism. I understand that time stops at the speed of light, which is approx 300000km/s. but because time stops at the speed of light it appears to me to have two speeds- those being the speed it experiences which is...

I have been enjoying learning relativity from the book "A First Course on General Relativity". I came across a somewhat confusing experiment mentioned in Chapter 1.8, which I have attached here: Namely, I am referring to how you might measure ##t=0## as "the difference in readings of two...

A spaceship travels at the speed of light from the sun to the earth and back, infinite acceleration and deceleration. Sunlight takes about 8 minutes to reach earth. On the trip to earth, the sun seems to be frozen. On the trip back, sun activity appears to resume and is seen at 2x speed. The...

Looking at Kruskal diagrams, it seems to me we should not be able to see evidence of black holes. Assuming our frame is a hyperbola of roughly constant ##r## in such a diagram, as the black hole's constituent mass comes together time slows (from our POV) to the extent that it never crosses the...

In special relativity I can get ## \gamma ## , ## \frac {T_B}{T_A}=\gamma ## Why do I not go ##{T_B} - {T_A} = \gamma## ? ##T_B = \frac {2H} {c^2 - v^2}## . ## T_B ## is the moving light clock. ## T_A = \frac {2H} {c^2} ## . ##T_A ## is the stationary light clockI assume LaTeX doesn't work...

I'm struggling to wrap my head around the twin paradox in special relativity especially when dealing with multiple vectors. In my thought experiment say I have a set of twins. Both set out in opposite directions and intend to sling shot around two different black holes(luckily equidistant from...

If a person was rotating on a verticle axis from head to toe like the Earth or quasar. If nothing can go faster than light, from the person's perspective looking at the stars traveling across the night sky, if you increase the rotation of the earth, stars further than a certain critical distance...

According to Einstien's theory of evolution, the closer to the speed of light that an object travels, the slower it appears to move to an outside observer. (see https://www.thenakedscientists.com/forum/index.php?topic=40951.0) To take this to the next step once an object crosses the event...

Hi I have 2 questions. There are 2 planets and one clock on each of them. One of them has a bigger gravitational field strength. And two clock have same distance from the core. 1-) Does time dilation occur between two? Which clock ticks slower? 2-) If time dilation occurs, which formula...

Special relativity says that all clocks will show same time dilation, irrespective of clock mechanism. But Time period of a clock is a formula that must continue to hold even if time dilates. Let us look at a tuning fork clock. Here time period depends on the dimensions of the vibrating...

I hope this is the right forum for this question. Imagine alien tech allows them to travel 1 million light years to Earth instantaneously. No thrust, vector, propulsion was involved. They didn't have to approach the speed of light, with its attendant increase in mass. Having arrived at earth, in...

Hello, I'm self-studying Ta-Pei Cheng's Relativity, Gravitation and Cosmology. Problem 2.8 is the following: Two spaceships traveling in opposite directions pass one another at a relative speed of ##1.25 \times 10^8## m/s. The clock on one spaceship records a time duration of ##9.1 \times...

Homework Statement A visit to Regulus is on my bucket list. However, it is 77 light years away. Assuming I will live only another 40 years, can I make it to Regulus? How fast would I have to travel (at constant speed) to get there in 40 years? Homework Equations t1 = t0...

So there will be a few hypothetical in the original story here, but in the end ill wrap it up with what I believe are facts. My question, how does Einstien’s theory of relativity interact with consciousness? Let’s say I have a twin, he becomes a farmer and I become an astronaut. I go to space...

If we assume I live in Jupiter and there is one year passed in my clock how many years passes in the earth? And how can I use that Equation in the attached?

So, I have been thinking about TRAPPIST-1 and how far away that system is from us. It is 40ly away from Earth, according to our frame of reference. This is often put in a way that makes one think that even at speeds close to that of light, it will take almost 40 years to get there. The muons in...

Homework Statement You approach an enemy ship at a speed of 0.5c measured by you, and the ship fires a missile toward your ship at a speed of 0.7c relative to the enemy ship. What speed of the missile do you measure, and how much time do you have measured by you and the enemy ship before the...

Suppose that we want to compute the total time dilation for a clock located in an orbiting satellite relative to the clock in our cell phone on the ground. Consider two different approaches below. 1. Use special relativity and compute time contraction due to velocity. Use approximation of...

I put the prefix as intermediate because I wasn't really sure how complicated of a question this is, I am currently a junior in high school... So basically if you were to have two spaceships with people the exact same age in them traveling at 99% the speed of light and they were traveling...

Hello I have a question about how time effects velocity:So we have a car on Earth traveling 200m with 5 seconds we get that car moves 40m/s and 40x3600=144000 and 144000:1000=144km/h so car on Earth travels 144km/h now let's consider a that there is observer on spacecraft traveling 0.5c...

Imagine a disc witch has a radius of R=1000m and a mass M=1000kg, this disc sits on an cube that is considered static it has no velocity in any direction whatsoever. There is a light clock with the length L=17.45240644m (approximately the same as the arc length for 1 degree on the disc θ=1)...

Homework Statement As outlaws escape in their getaway car, which goes 3/4c, the police officer fires a bullet from a pursuit car, which only goes 1/2c. The muzzle velocity of the bullet (relative to the gun) is 1/3c. Does the bullet reach its target according to Galileo? According to Einstein...

Homework Statement You are watching a race between two space ships who pass you moving at different constant speeds. In your reference frame, both ships are the same length while moving. It takes the first ship 26.8 minutes to get to the finish line a distance 14 light-minutes away. It takes...

Hi. Alright, so I'm not extremely informed with matters regarding special relatively so I have some basic questions that I'd like to ask you guys. My first question is that for an individual approaching near light speeds, would slowly moving objects appear to be moving much faster? The person...

[don't know whether i is the correct thread prefix, will change if requested/possible] Now I will start off by saying I'm only an interested lay person, and haven't studied this but was thinking about time dilation and it's correlative effects with gravity. Higher gravity, time slows down...

would that person go into the future?why? also if i travel 1,000,000 m/s on Earth and my friend travels 20m/s per second on Earth would we experience 2 different time frame? so basically the second question is if someone travels a different speed than me on Earth whether the difference of speed...

Hello. I need some help understanding time dilation. So the idea is that moving clocks tick slowly. Say there was an observer A who, by his frame of reference, is stationary, and he sees an object B moving past it at high velocity. From what I understand, to A it would appear as if B's clocks...

is magnetic repulsion and attraction is due to the bending of curvature of spacetime?

I was looking at Time Dialation a bit today and some of the experiments with it. Considering time goes approximately 1/3 as fast as normal, under 100% the speed of light, what would happen if you went past the speed of light with a craft capable of warping. Would it have no effect due to the...

Homework Statement A speaker emitting sound at a frequency of 20 Hz is moving in the +x direction between two detectors. The speaker is moving at a speed of 30 m/s and the detectors are wired so that they flash red (λ = 700 nm) when the pressure is a maximum and green (λ = 700 nm) when the...

Homework Statement An astronaut went to sun from Earth by a rocket. According to the clock in the rocket, the traveling time was 5 minute. What was the velocity of the rocket? ( Earth is 8 light minute away from sun) Homework Equations t = \frac {t_0}{\sqrt {1 - \frac{v^2}{c^2}}}The Attempt at...

I was recently exploring time dilation from Gravity and from velocity and I came up with an interesting derivation that I have not seen before. I was wondering if there is a paper published showing these relationships like this before and where I could find it? First you start with the...

I am doing a presentation and want to make sure I'm not misunderstanding something very fundamental. My argument goes like this: t0 = ϒt Santa is moving very fast and from his point of view he is in proper time. This means that if it takes him t0 seconds to deliver a present, the amount of...

I have always been confused about time dilation in General Relativity. In the twins paradox, it is the traveling twin that ages slower. However, could you not just as easily say that it is the non-traveling twin that is moving away from the other? So why is it the traveling twin and not...

Assume observer is located on the surface of the Earth with a small amount of time dilation due to gravity. There are two beams of light moving approximately parallel to the surface of the Earth at some moment in time and the reflection of the beam off some objects back to the observer is being...

would time dilation occur if for example, i was making a hydrogen atom spin with the center of spin the atom? would time dilation occur? because it didn't really traveled distance... or, if so spin a muon, would it decay faster if i was to spin it in an incredible amount of speed? but then if...

Hi All, I am new to these forums. I've been studying relativity in my down time at work and I am having a bit of trouble understanding why gravity doesn't offset velocity in the popular "aging/time travel" theory/scenario. I’ll explain: What I think I understand: The speed of light is...

Homework Statement A Nova is a sudden, brief brightening of a star. Suppose Earth astronomers see two novas occur simultaneously, one in the constellation Orion and the other in the constellation Lyra. Both nova are the same distance from Earth, 2.5 E 3 c.y (lightyear) and are in exactly...

I have no idea if I am picturing this whole scenario wrong, so please hear me out and try to point me in the right direction. Anyways, say we have a fast moving rocket with a person in it. Lightning strikes a side of it. So the light traveling from the bolt to the person/observer is traveling...

I love Physics! I've been thinking about if... you were in a room with a window, bouncing a ball... and you were looking at another building where you could see a room with a person bouncing a ball, but ... their time was moving at half speed (Caused by gravitational time dilation only ( not...

Can anyone prove that Time Dialation affects biological systems?

Hi All.. I have a basic doubt in time dilation theory. As per time dilation theory, when an object moves with the velocity of light, then relatively its time becomes zero. In that case, light is traveling at 'velocity of light'. So for light, there is no age? Or I misconcepted time dilation...

A spaceship has managed to accelerate to 86.6% of lightspeed. Focusing on special relativity would fuel consumption remain the same, better, or worse as opposed to traveling at non-relativistic velocities, what about breathable air? I understand that the rate of fuel consumption would...

Reading Brian Cox and Jeff Forshaw's book "Why does E=MC2". They mention that satellites speed up with time, but, then reading Wiki it says the crew of the ISS experience the slowing of time. Which one is correct? I'm slightly confused. Both experience a weaker gravitational pull and high...

Hi. Just watched a Nova special with Brian Greene, "The Fabric of the Universe/The Illusion of time", describing significant time dilation when two frames are moving towards or away from each other at low velocities, when the two frames are separated by great distance. This left me with a...

When you derive the time dilation equation, and you see the light move straight down in one frame and in the other frame you see it move on a diagonal because the object is moving. My question is in the moving frame when you use the horizontal distance to derive the distance that the...

In special relativity physicists talk about time dilation, saying that as an object moves faster relative to another that its "clock" moves slower and therefore time slows down. Could it be fair to say that time doesn't actually slow down, but all matter and energy reactions slow down and...

Special relativity Length Contraction and Time dilation question Homework Statement Planet X is 18 Light Years from earth, A spaceship moving towards the Earth at a speed of 0.82C (Measured from Planet X) fires a series of 1.2 cm long and 2.1 gram mass (as measured by the pilot) projectiles...