Questions tagged [spacetime-dimensions]
Use this tag for dimensions of a manifold, typically the space-time. DO NOT USE THIS TAG for dimension of a physical quantity nor for the size of an object.
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General relativistic simulation of compact binary system mergers in higher dimensional spacetime
Are there numerical studies of the merger of compact binaries in higher dimensional spacetime? Can anybody suggest any?
I cannot find anything, but I am probably using the wrong query.
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References on experiments for the number of spacetime dimensions [closed]
I am looking for references on experiments that try to measure the number of spacetime dimensions. I am looking for paper in any field, such as astrophysics, cosmology or particle physics. It is ...
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Why superconformal algebras exist only for spacetime dimension $d\le 6$?
I'm looking at the proof that superconformal algebras exists only at $d\le 6$, while supersymmetry exists in arbitrarily large dimensions. In Eberhardt's notes https://arxiv.org/abs/2006.13280 section ...
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Physical interpretation of higher dimensional Dirac matrices
Note: I have already checked this post and some others on the topic of this question, but they all seem to address the confusion of why the Dirac matrices have the dimension they have, which is not ...
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Only good QFTs have $D\leq 6$?
I am watching this seminar by Vafa and around the 9 minute mark he makes the statement that "without gravity we have found QFTs up to $D=6$. We haven't found any with higher dimension which are ...
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Is it possible that space can exist without time in some extreme cases like inside a black hole or before the Big Bang? [closed]
Is it possible that space can exist without time in some extreme cases like inside a black hole or before the Big Bang?
Clarification (from space without time) I for example mean that the axis of time ...
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What would Spin Operator and Spin State Vectors be in higher dimensions?
If we represent spin quantum state of a particle in $\pm z$ direction with $\vert\pm\rangle$ then we know that the state vectors in remaining $x$,$y$ directions would be such that:
$$\vert\langle S_x;...
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Can a universe with only one spatial dimension and one time dimension still produce complex physical behaviour? [closed]
Can a universe with only one spatial dimension and one time dimension still have meaningful physics? For example, can quantum fields in 1+1 dimensions produce effects similar to higher dimensions, or ...
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Can Newtonian mechanics be applied in higher spatial dimensions like 4 or 5, and what changes in orbital stability? [duplicate]
I was wondering about the applicability of Newtonian mechanics in more than three spatial dimensions. In 3D, we know that Newton’s laws of motion and the inverse-square law of gravity or ...
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Really, What Is So Special About 3 Spatial Dimensions? [duplicate]
The dimensionality of space is quite arbitrary. You can validly define properties of any $n$ dimensional space. Why, I wonder, do we live in a 3-dimensional world (considering the spatial dimensions ...
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Dimensionality of spinor representation for group ${\rm Spin}(n)$
Rather simple question that I'm sure has been asked before, but I haven't been able to figure out a way to phrase it that the search engine understands.
As I understand, the group ${\rm Spin}(n)$ is ...
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Coleman-Mandula theorem in 3 spacetime dimensions?
The classic Coleman-Mandula theorem was established in $d = 4$ spacetime dimensions. This was generalized to hold for all spacetime dimensions $d \ge 4$ in Pelc & Horwitz (1997) (an added benefit ...
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Dimension of Lorentz Group (as a Lie Group/Manifold)
The restricted Lorentz subgroup, $SO^{+}(1,3)$ is a subgroup of Lorentz Group, which has a real dimension 6. What then is the manifold dimension of $SO(1,3)$, the full Lorentz Group?
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Can negative dimensions have a physical meaning? (e.g., in string theory) [duplicate]
I was playing around with the formula for the volume of an $n$-dimensional sphere, and out of curiosity, I tried plugging in negative values for the dimension $ n $. Surprisingly, the math still works ...
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Is it a coincidence that the inverse-square law aligns with the Euclidean norm? [duplicate]
The Euclidean norm applies to all dimensionalities whereas the inverse-square law, or order of surface area, changes. In our universe the exponents align. Is this a coincidence, or as Einstein would ...
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