All Questions
114
questions
1
vote
3
answers
175
views
Seemingly equivalent linear form of the Sagnac effect
This is a derivative of the question regarding the Sagnac effect. Judging from the metric $ds^2=-dt^2+(rd\phi)^2$ for a constant $r$ for this question, it should be no different from that on a line ...
2
votes
3
answers
193
views
Sagnac effect viewed in the rotating frame
Consider the Sagnac effect. It is quite simple viewed from the rest inertial frame what the time difference should be. However, if viewed from the frame fixed to and rotating together with the emitter/...
0
votes
0
answers
26
views
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 ...
0
votes
1
answer
175
views
How is special relativity explained by general relativity?
To be more specific about this, I am under the below assumptions and then will explain my question further. Please let me know if any of the assumptions are incorrect.
(1) Special relativity describes ...
1
vote
1
answer
89
views
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. ...
0
votes
0
answers
51
views
Geometric definition absolute velocity in affine spaces
currently I am reading the following paper by Halvorson and Clifton (https://arxiv.org/abs/quant-ph/0103041) where they try to argue that localizable particles are inconsistent with relativistic ...
0
votes
2
answers
104
views
Justification of string breakage in Bell's Spaceship paradox from observer's frame
In Bell's Spaceship Paradox, are there any direct observations that the stationary observer can make that would justify the breaking of the string without taking into consideration as to what's taking ...
41
votes
4
answers
5k
views
Rotate an object about the time axis
Is there a notion of rotating an object about its time axis? I'm not sure if this question totally makes sense, but it seems intuitive to me that an object with dimensions in the three spatial ...
2
votes
3
answers
130
views
How to prove: Are perpendicular coordinates (wrt to relative velocity) unchanged (or only scaled) while deriving the Lorentz Transformations?
Thank you for helping with this question and I'm sorry if it's kind of stupid.
TLDR: In many textbooks and other derivations deriving the Lorentz Transformations, they omit coordinate axes orthogonal ...
1
vote
1
answer
52
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Is distance irrelevant to time if two events are in the same inertial reference frame? [closed]
Assuming that there is some observer "O" at location 0, and there are two events A and B, with B occurring 1m farther from A. Both A and B are equipped with two synchronized clocks reading ...
-1
votes
3
answers
174
views
Trajectory of light send from a moving box [closed]
In a closed box in inertial motion a ball bounces up and down vertically. Apart from this movement, the ball is motionless relative to the box. The trajectory of the ball seen by a stationary observer ...
1
vote
1
answer
146
views
Why is the flat spacetime of special relativity not a linear vector space? [duplicate]
Why is the flat spacetime of special relativity, not a real linear vector space? It seems to satisfy all the axioms for a set to form a vector space. I mean adding to spacetime points $(t_1,\vec{r}_1)$...
1
vote
5
answers
497
views
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 ...
0
votes
2
answers
250
views
What is concept of left region of rindler space-time?
A accelerated object follow a hyperbolic path in a Minkowski spacetime diagram. Minkowski spacetime has two regions: left (I) and right (II) regions of Rindler spacetime, as it is shown in the picture ...
0
votes
4
answers
140
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Simultaneity of events
Apologies, this thought has been bugging me and I am... Simple
Consider two observers.
One on Earth (stationery) One travelling away from Earth at some
appreciable % of c
If the spaceship sent a ...