/sci/ - Science & Math

[Anonymous No.11849819]

What is tensor

[Anonymous No.11849825]

Tensors are functions on steroid with multiple inputs and outputs

[Anonymous No.11849835]

>>11849819
a multilinear function

[Anonymous No.11849838]

>>11849819
it's just an array

source: CS degree

[Anonymous No.11849842]

>>11849819
"tensor is an array" is the new "0.999... is not 1"

[Anonymous No.11849851]

>>11849835
This.

[Anonymous No.11849968]

>>11849819
all rank-2 tensors can be written as square matrices, but so can rank-2 pseudotensors. Vectors can be written as column (or row) matrices, but so can pseudovectors. Matrices are just a way of organizing numbers. Matrix operations do work the same way as tensor/pseudotensor operations, but only if you order the matrices correctly. With tensors/pseudotensors you don't have to worry about multiplication order. With matrices, you do. That's why using matrix notation is not recommended.

[Anonymous No.11849976]

>>11849819
tensor product is the space where bilinear maps become linear
if you have a vector space E of dimension n or a module E of rank n and a vector space F of dimension m or a module F of rank m the tensor product is isomorphic to the space of dimensions mn or module of rank mn.

[Anonymous No.11850013]

>>11849968
>Matrix operations do work the same way as tensor/pseudotensor operations, but only if you order the matrices correctly. With tensors/pseudotensors you don't have to worry about multiplication order. With matrices, you do.
what? what matrix operations are you talking about? and what do you mean you don't have to worry about multiplication order with tensors?

[Anonymous No.11850159]

>>11849819
It's a point with an attitude.

[Anonymous No.11850390]

>>11849819
nice to see someone using my frog

[Anonymous No.11850403]

>>11849819
It's anything that transforms like a tensor.

[Anonymous No.11850411]

>>11850403
https://youtu.be/Cv6tuzHUuuk?t=2m30s

[Anonymous No.11851448]

>>11849819
All alleged Black Hole models pertain to a universe that's spatially infinite, is eternal, contains only one mass, is not expanding, and is asymptotically flat or asymptotically not flat.

But the alleged Big Bang cosmology pertains to a universe that's spatially finite (one case) or spatially infinite (two different cases), is of finite age, contains radiation and many masses including multiple black holes (some of which are supposedly primordial), is expanding, and is not asymptotically anything.

Thus black holes and the big bang contradict one another - they're mutually exclusive. This is undeniable and clear as day. It's surprisingly easy to prove that neither General Relativity nor Newton's theory predict black holes to exist.

Despite numerous claims for black holes in their millions, none has ever been discovered. It's also not difficult to prove General Relativity violates the usual conservation of energy and momentum. There are fundamental contradictions contained in black hole theory, big bang cosmology, as well as in General Relativity. Numerical methods are therefore meaningless.

Oh and for those who'd like to use the defense that in an expanding universe energy isn't conserved and thus the "energy conservation law" is false and therefore all criticism of Einstein's field equations are incorrect, friendly reminder to you that Einstein required his field equations to satisfy the usual conservation of energy and momentum.

To do so he introduced his pseudotensor which has been demonstrated to be entirely meaningless – see: https://z.zz.ht/98S5i.pdf and related: https://z.zz.ht/ZMeXe.pdf

Big Bang theory is based upon Einstein’s field equations. Since the field equations violate the usual conservation laws, the theory of a big bang is fundamentally flawed.

[Anonymous No.11851455]

>>11851448
Therefore, invoking a Big Bang to attempt to circumvent the violation of the usual conservation laws is a circular argument and therefore completely invalid.

Furthermore, Einstein's field equations are nonlinear and so the principle of Superposition doesn't hold in General Relativity. But it does hold in Newton's theory.

Thus if X and Y are two different solutions to Einstein's field equations, then the linear combination of aX + bY, where a and b are scalars, isn't a solution. Physically this means that one can't simply pile up masses and radiation in any given spacetime to obtain multiple masses and radiation. Additionally, there are no solutions to Einstein's field equations for two or more masses and there is no existence theorem by which it can even be asserted that the field equations contain latent solutions for two or more masses. Thus it's not possible to insert a black hole universe into a big bang universe or into another black hole universe, or to insert a big bang universe into a black hole universe or another big bang universe.

Nevertheless, Einstein's followers routinely and incorrectly claim the existence of multiple black holes from objects such as stars by means of irresistible gravitational collapse.

Now read pic related if you want to understand all of this in depth.

[Anonymous No.11851465]

>>11849819
>>11851448
>>11851455
https://www.youtube.com/watch?v=QBorBKDnE3U

[Anonymous No.11852121]

>>11851448
>>11851455
>>11851465
>wall-of-text schizo
errytime

[Anonymous No.11852125]

>>11851448
>>11851455
>>11851465
>eu garbage
into the trash it goes

[Anonymous No.11852135]

>>11852125
whats this new eu thing I keep hearing

[Anonymous No.11852139]

>>11849819
a numerical array of matrices

[Anonymous No.11852143]

>>11850013
Tensor product is commutative iff one of factors is zero so i dont know what is he on about.
There is also a wedge product but there are several ways to define it and its really dependent on the structure you work with how complex definition you will use. And it works on alternating ones.