All Questions
11
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Generalizing the Galilean law of addition of velocities using the Lorentz transformation [closed]
I am reading about how to generalize the Galilean law of addition of velocities using the Lorentz transformation, but I am confused about one step.
Here, I have the following equations for Lorentz ...
- 63
-1
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3
answers
104
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Why doesn't Galilean relativity lead to a contradiction in SR?
Two identical spaceships commanded by Alice and Bob are at rest next to each other in outer space. The clocks of the spaceships are synchronised; and when they are close by Alice can see Bob's clock ...
- 99
6
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2
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431
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Confusion regarding bundle structure of Galilean spacetime in Penrose's The Road to Reality
I am reading Roger Penrose's The Road to Reality. In section 17.3, I encounter the following passage. To give a context, Penrose was explaining that even though an Aristotelian spacetime can be ...
- 682
4
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2
answers
724
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How can we talk about motion when space at different times can't be compared? (Explanation of Galilean Spacetime by Penrose)
In Galilean dynamics, we do not have just one Euclidean 3-space $E_3$, as an arena for the actions of the physical world evolving with time, we have a different $E_3$ for each moment in time, with no ...
- 7,980
6
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1
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467
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The metric of world lines in Newtonian and Galilean spacetimes
Consider a flat Newtonian or a flat Galilean 2+1 spacetime. So, mainly a flat 2D Euclidean space, evolving over time, where each time-slice is connected with the next one by a world line. Like in this ...
- 431
10
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3
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1k
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Why is absolute time considered an axiom of Newtonian mechanics? What statements are based on this axiom?
I guess absolute time is associated to classical mechanics because people like Newton believed in that concept, but are there actually any statements whose derivation is based on this assumption?
I've ...
- 1,801
2
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3
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386
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Can we say that Galilean Spacetime has the signature $(0,0,0,+)$?
Minkowski Spacetime can be treated as either having the signature $(+,-,-,-)$ or more commonly $(+,+,+,-)$ as in Minkowski Spacetime the spacetime interval between two events is the quantity that is ...
- 2,001
0
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2
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239
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Absolute Space & Inertial Frames
When we solve the twin paradox we say something like the traveling twin has a Rindler Metric while the stationary twin has a Minkowski metric, or more plainly, the traveling twin experiences non-zero ...
- 749
2
votes
1
answer
601
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What was Newton's idea of absolute space and time?
When one says that Newton believed in the concept of "absolute space" and "absolute time" does it simply mean that the length interval between two points in space and time interval between two events ...
- 11.8k
-1
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5
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764
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How do we mathematically know for sure that absolute time is abandoned in relativity?
It is an often mentioned assumption in physics that in going from classical to relativistic spacetime the main difference is that the absolute time postulate holding in the former is "relaxed" or ...
- 218
0
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102
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Proper notation when working with three Euclidean spatial coordinates in a setting with a time parameter
The How does the Euclidean metric is the symmetry group of Euclidean space. It includes rotations and translations.
Say I consider an Euclidean space and a time parameter. How does the Euclidean ...
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