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/sci/ - Science & Math


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9159593 No.9159593 [Reply] [Original]

Can curved spacetime become knotted?

>> No.9159594

>>9159593
>tfw you do so and the knot locks the person out of the universe

>> No.9159614

Does it matter?

>> No.9159617

>>9159614
Yes

>> No.9161093

There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity. Put a spinning gyroscope into orbit around the Earth, with the spin axis pointed toward some distant star as a fixed reference point. Free from external forces, the gyroscope's axis should continue pointing at the star--forever. But if space is twisted, the direction of the gyroscope's axis should drift over time. By noting this change in direction relative to the star, the twists of space-time could be measured. "We measured a geodetic precession of 6.600 plus or minus 0.017 arcseconds and a frame dragging effect of 0.039 plus or minus 0.007 arcseconds," Geodetic precession is the amount of wobble caused by the static mass of the Earth (the dimple in spacetime) and the frame dragging effect is the amount of wobble caused by the spin of the Earth (the twist in spacetime).

The Gödel metric is an exact solution of the Einstein field equations in which the stress–energy tensor contains two terms, the first representing the matter density of a homogeneous distribution of swirling dust particles, and the second associated with a nonzero cosmological constant (see lambda vacuum solution). It is also known as the Gödel solution.

Because of the homogeneity of the spacetime and the mutual twisting of our family of timelike geodesics, it is more or less inevitable that the Gödel spacetime should have closed timelike curves (CTC's).

The various related solutions appear to all involve treating space-time as a four dimensional fluid. While forming a loop can be achieved (given some extreme assumptions about the energy dust needed); forming a knot in a three dimensional fluid seems impossible. So also, one would assume, that is the case in four dimensions.

>> No.9161692

>>9161093
So space time has the properties of a fluid?

>> No.9161708

>>9161093
>homogeneity of the spacetime
nigga you a homo

>> No.9161715

>>9161093
Related

https://youtu.be/pKO2Dl2dupY

>> No.9161877 [DELETED] 

>>9159593

Cogere physicae et geometric et causa. Curverii temp est non existere. Causa et effect est in movere. Movere est in top. Temp est non form.

>> No.9161879
File: 45 KB, 697x389, electroVShydro.jpg [View same] [iqdb] [saucenao] [google]
9161879

>>9161692
Space has something like density and compressibility that defines the speed of light.

[math]
\displaystyle
c = \frac{1}
{ \sqrt{ \varepsilon_0
\mu_0
}
}
[/math]

>> No.9161886 [DELETED] 

>>9159593

Ego spottere retardii homini in amrica in washington universit. Stephen Hwaking in black jeans jacket. Hawking non physicaei ergo non belevere in stupidii sentenci.
Hawking perceptere voicei in cereb.

Legionii homini et 4chan vadere legionii. Legionii conquere Amerika in present excursio aggressii, pretere! Ad victori, in glori regress.
Ego revelere non fals informari ergo non /x/.
Memento cancerii quanti de Amerika est in futur eradicarii.
>Omni de amerikanii physicaei est cancerii et retardii.

Cogere Newton, Lichtenberg.

>> No.9161891

>>9161886
pretentious fuck
>>>/lit/

>> No.9161898 [DELETED] 

>>9161886
Ego forgetere in past: Stephen Hawking est in scientology. Retardii homini, et deserti in cereb.
Observere Hawking ad perceptere veritas in ego sentenc.

>> No.9161901 [DELETED] 

>>9161891
Exego movere ad /lgbt/. Retardii transsex.

>> No.9161904

>>9161898
>>9161901
just rub one off alreadyand spare the rest of us

>> No.9161971

>>9161904
ITS A NORMAL DOOD

>> No.9162001

>>9161886
>All the american physicists are retarded
I'm alright with that, but what language are you speaking?
>inb4 latin

>> No.9162093

>>9162001
latin

>> No.9162193

>>9161879
pretty sure the first one is vorticity, not circulation.

>> No.9162204
File: 91 KB, 577x576, 98959919bd9c4b8aac6c8f5581c15d512cf9f945d57033ddd20dd84578f8e8bc.png [View same] [iqdb] [saucenao] [google]
9162204

>>9162093
Almost

>> No.9162321

how would you knot something without ends?

>> No.9162330

>>9162193
https://arxiv.org/pdf/1003.0070
A quaternionic unification of electromagnetism and hydrodynamics
page 7