All Questions
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Question on Example 5.9 of Prof. Hartle Gravity textbook
I'm reading the Gravity Hartle book (ed.2003) and I'm having trouble with the question in the last part of Example 5.9 - Frequency Measured by an Accelerating Observer. More specifically the problem ...
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What does hypersurface of simultaneity exactly mean?
HSS - "Hyper Surface of Simultaneity"
Listening to different sources online I understood that HSS for a observer represents the points that are at same moment of time.
Consider a 1d world. ...
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2
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Do all observers see the same curved spacetime -- or would that be a (prohibited) preferred inertial frame? [duplicate]
My question -- pardon if not asked in the most incisive scientific prose
Do all observers see the same curved-space time?
Let me clarify:
Given that objects traveling at different relative speeds will ...
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2
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General Relativistic version of the Lorentz factor
In curved spacetime, the Lorentz factor is different than that in flat spacetime.
Is there any expression that gives the Lorentz factor for any arbitrary metric tensor?
user355398
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5
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Is relativity of simultaneity an "observer issue"?
There are some threads about this, but some answers seem to disagree.
First, this is what Einstein said on this matter:
The light rays emitted by the flashes of lightning A and B would reach him ...
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Does a person in relativistic circular orbit have the same age as a stationary person at the centre? [duplicate]
Consider a circular orbit whereby a spaceship travels around near the speed of light.
Say the radius of this orbit is such that the angular velocity is low.
An observer is placed at the center of the ...
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2
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In spacetime what is the time $t$ on the $ct$ axis?
In spacetime, I understand that we multiply time by the speed of light to deal with homogeneous distances over the four axis, space and time.
But what does $t$ refers to precisely? Where is $t$ ...
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Minkowski Diagrams and Synchronized Clocks [duplicate]
While using Minkowski diagrams for studying spacetime and time dilation, I came across a problem that seems like a paradox to me, but may actually just be from a lvl of understanding.
Imagining two ...
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At what constant speed should I travel one light-second to make my time and a stationary person's time 1 second off?
at what constant speed should I travel one light-second to make my time and a stationary person's time 1 second off?
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3
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What if the Twin Paradox use the "day time" and "night time" on earth as their age reference?
I've searched this site, I found a similar question here but not exactly like mine.
So I can't understand the Twin Paradox when I use the "day" (bright time) and "night" (dark time)...
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What does this spacetime diagram mean?
I'm reading a book called "Reality is not what it seems: the journey to quantum gravity" by Carlo Rovelli and I'm struggling to understand this diagram that is part of the chapter about ...
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3
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Can there be simultaneity without a reference frame?
I have been reading about the concept of the relativity of simultaneity which states that whether two events, separated by space, occur at the same time is relative to the observer's reference frame. ...
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"Different reality" inside a black hole
why does our perception of space and time entirely change inside a black hole? And why does time not stop inside it from the perspective of the inside observer, however, extremely slows down for the ...
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How to tell who is experiencing time slower and who faster when travelling at different speed?
I am trying to understand time dilation w.r.t velocity. Its said that when a satellite travels around earth (at speed more than a synchronized clock on earth which is stationary w.r.t earth), it ...
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Acceleration/gravitation vs velocity and the Twin Paradox
I see in Professor Pogge’s explanation
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html dec. 2020.
that
“Because an observer on the ground sees the satellites in motion relative to ...
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