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28 views

How to travel between two stationary worlds in the least amount of proper time?

I was intrigued by this question about minimizing the travel time between two worlds that are at rest with respect to each other, and disappointed that the answer turned out to be trivial. However, I ...
25
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4answers
3k views

How to travel between two stationary worlds in the least amount of time? (time dilation)

Let's imagine there are two, isolated, stationary worlds in space (called A and B), very far apart from each other. I live on World A, and some aliens live on World B. I want to learn about the ...
2
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1answer
27 views

Time dilation : Hourclock on Jupiter

Time slows down on Jupiter because of higher gravity, but Hourclock(sand clock) run faster due to higher g. If I am correct than how?
0
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2answers
143 views

Hypothetical effect of Solar System/Orion Spur traveling near speed of light

I was hoping that some genius could explain what we would observe in the universe around us in the following hypothetical scenario in which the earth itself were traveling at or near the speed of ...
2
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1answer
86 views

Why is light affected by time dilations in space-time curvatures

My previous question on this site gave me an answer to what affects light - space warping or time warping. The answer is- both. But what now doesn't make sense to me is why light is affected by time ...
4
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2answers
97 views

Is light affected by space warping or time warping?

Gravity, according to the General Theory of Relativity, is simply the curvature of space-time. Objects in the universe move through space-time in geodesic paths. Also, the most interesting part is ...
2
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2answers
78 views

Is there a temporal difference between planets due to the sun's gravitational field?

since the Sun generates a gravitational field it also generates gravitational time dilatation. Hence, time further from the Sun should pass quicker than in its proximity. Can we, therefore, say that ...
0
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1answer
60 views

Light moving toward a moving observer's reference frame

The speed of light is supposed to be the same for all observers in an inertial frame, no matter the observer's speed. As a result, time slows down for observers moving quickly, and this explains why ...
5
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2answers
88 views

Spacetime diagrams and their interpretation

Recently started an introductory course of relativity, and started learning about space time diagrams. I couldn’t figure out what are the uses of a spacetime diagram as an alternative to Lorentz ...
0
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1answer
46 views

Question about position dependence of time dilation?

I found this picture from a physics stack exchange question on time dilation: Time dilation all messed up! I am now returning to it a few weeks later and was wondering if I am correctly interpreting ...
1
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0answers
56 views

What would be the time dilation standing on a neutron star in comparison to earth?

What would be the combined gravitational and velocity time dilation one would experience if they stood on the surface of a neutron star in comparison to standing on the earth's surface? Specifically, ...
1
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1answer
31 views

How much does time-dilation effect our observance of the most massive objects in our solar system?

Disclaimer: I'm kind of a newb, so I apologize if this question is not well formed. Please comment if anything is unclear, and I will do my best to make corrections. Reading this post about time ...
-1
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1answer
33 views

Respect to What Time is Calculated in Space

This may be the silly and stupid question but I have read that time appears to move slower near massive objects because the object's gravitational force bends space-time and the phenomenon is called ...
-5
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1answer
41 views

What do you think of this conceptualization of the universe and time dilation? [closed]

So the universe is ever-expanding. It's been expanding in all directions since the Big Bang, like how a sponge expands when you give it water. The universe is made of a fabric known as space-time. The ...
0
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4answers
91 views

When photons are moving at the speed of light, how come they change in position?

From what i know, photons are moving at the speed of light and that means the time that photons are experiencing is zero, but here is the thing... If the time is zero how can they travel astronomical ...
6
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1answer
150 views

Twin paradox with one twin in orbit, one in radial free-fall

Many questions on Physics SE relate to the twin paradox, but I did not find any that ask this specific question. Suppose that object A is in a circular orbit around a spherically symmetric, non-...
2
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2answers
120 views

What does it actually mean to say that time “speeds up” or “slows down”?

I was thinking lately about relativistic time dilation and time passing differently on other planets (which both, eventually turned out to be caused by the same principle). Now, quite naturally (as ...
2
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0answers
100 views

Can someone travelling close to the speed of light witness the end of the universe? [closed]

I have read that objects with non-zero rest mass cannot attain light speed $c$. But for the sake of this question let us assume that Mr. X can get as close to $c$ as he wants. So this means that an ...
0
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1answer
310 views

Is time passing really differs on other planets/in interstellar? [duplicate]

I am aware of the idea of time dilation (which I, by the way, asked another question about) on speeds, that get close to the speed of light. Though, I wonder what other (if any) forces and laws affect ...
3
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4answers
136 views

How close should you get to speed of light, in order for time to be dilated?

Recently I was watching Carl Sagan's Cosmos: A Personal Voyage. In episode 8 ("Journeys in Space and Time") there is a scene presenting the idea of time dilation, due to traveling close to the speed ...
3
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2answers
119 views

Effect of time dilation in Cs atomic clocks?

Let's say, Observer A is at rest and Observer B is in a spaceship moving at a significant fraction of speed of light. B synchronized his atomic clock with A's when his spaceship just passed A. Now, ...
0
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1answer
50 views

Is the formula for time dilation applicable only in 1D?

According to time dilation formula $$ \Delta t_{observer} = \frac{\Delta t_{proper}}{\sqrt{1-(v/c)^2}} $$ I have basically two questions: (1) Is this formula applicable only for 1D motion, i.e. ...
0
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2answers
86 views

If we filmed what happens on an extremely time dilated planet in realtime

Say there was a planet that experienced insane time dilation due to orbiting a black hole, say 1hr on there is 7 years on Earth (something like that), and that it was close enough to Earth for light ...
2
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2answers
86 views

Distance between events at relativistic speeds

The problem: A spaceship is travelling between Mountain $A$ and Mountain $B$, both of which erupt simultaneously as recorded by a scientist on the ground. The mountains are $300 \; \text{km}$ apart on ...
0
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1answer
69 views

How does gravitational time dilation affect how we age?

Suppose you could live on Jupiter without dying from anything except age, how much longer would you be able to live there compared to how long you could live on Earth?
2
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1answer
42 views

Can a system's orientation relative to direction of motion create additional relativistic effects?

Setup Consider an observer, at rest, holding two perfect clocks: The first perfect clock is ordinary--with no additional distinction. The second perfect clock has a special constraint, as it is ...
0
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1answer
47 views

How can we have different speeds relative to a same point for a same object?

A day last not the same at all altitudes (https://aapt.scitation.org/doi/10.1119/1.5000802), meaning earth has different angular velocities. What is the actual rotation speed of the earth to the ...
0
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3answers
113 views

Time Dilation Equations and Varying Interpretations

I have been seeing problems involving time dilation but the interpretation used by some people is not always the same. $$ \tag{1} \Delta t' = \gamma \Delta t $$ If we think about the twin B going ...
0
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2answers
75 views

Photon time dilation paradox

When traveling at the speed of light (v=c), left under the radical you would have 0. This answer would be undefined or infinity if you will (let's go with infinity). The reference time (T0) divided by ...
0
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2answers
98 views

How is time affected by the bending of space-time?

By Newton's Laws, we can calculate the effect of gravity, but he didn't give the actual reason for gravity. I searched the internet for it, but all the answers have this "bending of space-time" stuff. ...
1
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0answers
184 views

Derivation of Lorentz Contraction WITHOUT light roundtrip

A typical Lorentz Contraction proof relies on the axiom that "the speed of light is constant" and goes as follows. Given: Frame $F_1$ moves at speed $v$ relative to frame $F_0$. In frame $F_1$ sit 2 ...
2
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7answers
2k views

Why does gravity cause time dilation?

I know there have been several posts asking the same or similar questions, but I haven't been able to grasp this from reading any existing questions. My question is: why does gravity cause time ...
-1
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1answer
342 views

How does LIGO detect Gravitational Waves if they bend both space and time?

Please note that this is not an inquiry into the mechanisms of technology that LIGO uses to detect gravitational waves. Also, I am not a flat-earther. I was watching physicists vs. flat-earthers ...
0
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0answers
23 views

Time dilation due to gravity [duplicate]

I'm getting conflicting statements when it comes to time dilation due to gravity. Some sites say time slows down near the source of gravity and some say it's faster. Can anyone she'd some light on ...
0
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1answer
62 views

The ISS, acceleration and space time

This question/theory/thought has been stuck in my head for months and would welcome comments. Firstly, from my understanding, looking at NASA's website, the ISS cycles the earth 26 times in one 24 ...
-3
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1answer
113 views

Expansion of what? [duplicate]

When people say "the expansion of the Universe" they seem to mean the expansion of the space between mass-dense regions. However, my understanding is that space and time are intrinsically linked, so ① ...
4
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1answer
258 views

Is this spacetime diagram for the twins paradox correct?

The link at question is here: http://www.einsteins-theory-of-relativity-4engineers.com/twin-paradox-graphical-solution.html My question in specific is the loop in Jim's worldline. I know that ...
2
votes
1answer
97 views

The Time Freezing Room - Theoretically possible?

Imagine a room in your basement with a very special property: The time inside this room runs 60 times faster compared to the outside world. That means when you enter the room and spend there 1 day ...
5
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1answer
138 views

How does time behave inside a massive spherical shell?

According to General relativity the clocks in our satellites in the atmosphere tick faster than those on Earth, as they are farther from the gravitational well of Earth and are free falling. ...
3
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4answers
166 views

Is there a space-like equivalent of the Twin Paradox?

In the Twin Paradox, a travelling twin returns to the inertial frame of the twin that has stayed at home, and their clocks are compared. The readings on the two clocks are different, but still ticking ...
-12
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1answer
563 views

Time goes slower the faster you go. What happens to time if you go too SLOW? [closed]

Time dilation is clear about what happens when you go faster than an earth observer, and about what happens when you travel at c. But earth is also moving, and thus we humans are not at the slowest ...
2
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1answer
115 views

Does the center of a star age faster than its relativistic equatorial surface? If so, how does it maintain its speed and spherical shape?

Imagine a massive (the diameter is millions of miles across) star rotating on its axis at relativistic speeds. Assume, now, that the center of the star is stationary. Note that the center of the star ...
1
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0answers
61 views

Does everything in the universe exist for amount of time in range of “0 - infinity” at the same time? [closed]

Relativity principle says that every moving object experiences time differently, the faster you move the slower you age (the same goes for atoms, since everything is made out of them). Consider this:...
4
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5answers
616 views

What is the actual cause of time dilation? Does it depend on magnitude of velocity? Or does is also depend on direction?

Hi I was having after thoughts after learning about time dilation in relativity and had some questions. I was initially taught if there were two space ships traveling relative to each other, the time ...
1
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0answers
26 views

Can one observe a blackhole grow from outside its event horizon? [duplicate]

For an observer outside Black hole's event horizon nothing ever falls into the black hole . So if the observer waits for an eternity outside a super massive blackhole feeding on gas , will the ...
0
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4answers
523 views

How does gravity slow a clock at a distance?

If you have two identical clocks that are synchronized and then you move one significantly closer to a black hole but still far from the black hole, the closer clock will mark time slower than the ...
0
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1answer
56 views

Where would you get the most time, compared to everything else? [closed]

If from a photons perspective it doesn’t experience time and travels zero distance in zero time, and from anything else’s perspective light clearly travels and it takes time to do so, could there be ...
1
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0answers
85 views

Synchronized Clocks in Inertial frame

Will the synchronized clocks placed in an inertial frame remain synchronized forever?
1
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1answer
99 views

Travel time classical mechanics VS special relativity

Suppose a traveler is going from point A to point B at close to light speed. From the point of view of the traveler, what is the difference of travel time using classical mechanics or special ...
2
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1answer
221 views

Gravitational time dilation from the perspective of an accelerating rocket

A common thought experiment illustrating gravitational time dilation involves Alice and Bob in an accelerated rocket. Alice is above Bob. Bob fires periodic signals upwards. Alice observes the signals ...