All Questions
Tagged with galilean-relativity spacetime
19 questions
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Independence of Lagrange function from time and position
In Landau & Lifshitz "Mechanics", it is said that from the time/space homogeneity Lagrange function is independent from time/position. I always thought that homogeneity means that motion ...
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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
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41
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Is there a general methodology for causal nets of observables regardless of kinematics?
The typical definition of a causal net of observables in quantum theory is to consider, for the case of a (globally hyperbolic) spacetime $M$, the category of open sets $O(M)$ ordered by inclusion, in ...
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The limit of GR with infinite speed of light $c$
Just answer what you can. I don't mean the zero curvature flat space time version. I know that the Einstein Field equations use $c$ as a constant, but what would the universe be like if gravity was ...
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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 ...
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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 ...
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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 ...
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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 ...
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What is the symmetry group of Mach's spacetime?
Newtonian spacetime can be modeled as a geometric object $M$ (affine space or manifold with connection with an absolute time function etc. etc.) that is symmetric under the action of the Galilean ...
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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 ...
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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 ...
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Do Galilean (Euclidean) space transformations implies that time is absolute?
I recently read a paper where it says "if space is universally Euclidean, then time is universal" and I don't understand some key points about the implication.
To put in context, the author ...
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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 ...
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Is time an invariant of Galilean transformation?
Is time an invariant of Galilean transformation? By saying that I mean if there is a quantity analogous to spacetime interval in Lorentz transformation. What is the geometry of "Galilean spacetime"?
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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 ...
- 12.3k
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Galilean spacetime interval?
Does it make sense to refer to a single Galilean Invariant spacetime interval?
$$ds^2=dt^2+dr^2$$
Or is the proper approach to describe separate invariant interval for space (3D Euclidean distance) ...
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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 ...
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Relationship bewtween the principle of Galilean Relativity and absolute time
The principle of Galilean Relativity is:
The laws of Mechanics are invariant in every inertial frame of reference.
I say "laws of Mechanics" specifically because I'm referring to the principle ...
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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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