- Видео 251
- Просмотров 112 656
Mohammad Javad Azadi
Добавлен 8 мар 2020
Visual models of base reality. Get the source code from Porta: github.com/iamazadi/Porta.jl
One-to-Two Relation Between O(1,3) and SL(2,C)
See figure 1-14 in Penrose and Rindler, 1984.
What’s shown is a one-to-two relation between a restricted Lorentz transformation and the special linear group of complex dimension two, up to a boost. The topology of the relation is like the one-to-two relation between the special orthogonal group of real dimension three and the special unitary group of complex dimension two. Both spin transformations go through a four pi rotation. But, the restricted transformation, which is one the left side, returns to itself after going through two pi rotation. On the right side, the geometric structure of similar triangles with vertices: P, P prime and P prime prime, undergoes an unrestricted spin transf...
What’s shown is a one-to-two relation between a restricted Lorentz transformation and the special linear group of complex dimension two, up to a boost. The topology of the relation is like the one-to-two relation between the special orthogonal group of real dimension three and the special unitary group of complex dimension two. Both spin transformations go through a four pi rotation. But, the restricted transformation, which is one the left side, returns to itself after going through two pi rotation. On the right side, the geometric structure of similar triangles with vertices: P, P prime and P prime prime, undergoes an unrestricted spin transf...
Просмотров: 4
Видео
The Unrestricted Transformation of Spinors
Просмотров 152 часа назад
Dirac’s scissors problem: there are two sections of the null cone in Minkowski space-time. The temporal components of both sections is constant and equal to 1. The sections are related to each other with the same round metric, up to a scalar multiplication. The origin is labeled O whereas the North Pole is labeled as the point N. Remember that the North Pole of the anti-sky mapping is in Antarc...
The Special Linear Group of Complex Dimension Two
Просмотров 157 часов назад
Three scenes are shown. The main scene represents the abstract vector space of complex dimension two. But, the side scenes show two copies of the special orthogonal group of real dimension three. First, we mark the boundary of one SO(3) copy with sixteen vertices of a hypercube. Second, make a tangent frame at origin O and parallel transport it to the marked points. After, mark the frames with ...
Similar Triangles In Two Sections of A Null Cone
Просмотров 6616 часов назад
A null cone is in the tangent space of spacetime at point O. The line segment connecting point O to point N represents the temporal direction that is perpendicular to a cross-section of the null cone. But, two cross-sections are shown here, and the temporal direction of the second section is perpendicular to the spherical surface (a 2-sphere) centered at point O. Depending on the angle between ...
Cross-Sections of the Null Cone and a Conformal Structure
Просмотров 9319 часов назад
A null cone is in the tangent space of spacetime at point O. The line segment connecting point O to point N represents the temporal direction that is perpendicular to a cross-section of the null cone. But, two cross-sections are shown here, and the temporal direction of the second section is perpendicular to the spherical surface (a 2-sphere) centered at point O. Depending on the angle between ...
The Representation of a Spin-Vector with a Null Flag
Просмотров 11821 час назад
The representation of a spin-vector in terms of a pair of infinitesimally separated points P and P prime on y positive (anti-sky mapping) or, equivalently, by a null flag. See figure 1-10 in Penrose and Rindler 1984. iamazadi.github.io/Porta.jl/dev/newsreport.html
Stereographic Projection and Proper Rotation
Просмотров 167День назад
This shows the stereographic projection of point P in the image of anti-skymapping to point P prime in the Argand plane. The flat plane is Sigma, the perfectly spherical surface is S^ , and the surface on the left is Pi. The length of all line segments are 4pi and all of them are straight line segments connecting O, P, Q, N and P prime. Lastly, the seeming rotation is a spin-transformation appl...
News Report
Просмотров 2014 дней назад
Define Gauge Theory. iamazadi.github.io/Porta.jl/dev/newsreport.html
Non-Zero Vertical Motion with the Lie Bracket
Просмотров 5121 день назад
What do the Lie bracket and the Penrose staircase have in common? Every tangent vector in the tangent space of the three-sphere must be a linear combination of these vector fields: ``K_1``, ``K_2`` and ``K_3``. Suppose we have a differential equation where a tangent vector equals the rate of change of a smooth function from the 3-sphere to the real numbers. Then, the solution of the differentia...
The Geometry of Spin-Vector Addition
Просмотров 2321 день назад
The geometry of "spin-vector addition" is shown. The spin-vectors exist in a spin-space that is equipped with three operations: scalar multiplication, inner product and addition. The addition of spin-vectors κ and ω results in another spin-vector κ ω in the spin-space, which has its own flagpole and flag plane. Taking κ and ω as null vectors in the sphere of future null directions, the flagpole...
The Sum of Two Spinors
Просмотров 10128 дней назад
A spin-vector is named kappa and another spin-vector is named omega. The extra piece of information that makes spinors special is the flagpoles of spin-vectors. Using a differential operator in the plane of complex numbers, starting with zeta complex, the spin counterpart of the spin vector zeta prime equals zeta minus one over the square root of two times a constant named epsilon, over eta (th...
The Inner Product of Spinors
Просмотров 50Месяц назад
The phase of the inner product of spin-vectors is shown as a prism arc. In a Minkowski tetrad with bases t, x, y and z, (with signature ( ,-,-,-)) there are a pair of basis vectors for spin-vectors: omicron and iota. For example, the spin-vectors kappa and omega, each are linear combinations of omicron and iota. The product of kappa and omega is a complex number that has a magnitude and a phase...
The Phase of the Inner Product of Spin-Vectors
Просмотров 31Месяц назад
The phase of the inner product of spin-vectors is shown as a prism arc. In a Minkowski tetrad with bases t, x, y and z, (with signature ( ,-,-,-)) there are a pair of basis vectors for spin-vectors: omicron and iota. For example, the spin-vectors kappa and omega, each are linear combinations of omicron and iota. The product of kappa and omega is a complex number that has a magnitude and a phase...
The Relation Between a Spin-Frame and a Minkowski Tetrad
Просмотров 43Месяц назад
What is the relation between a spin-frame and a Minkowski tetrad? The spin-frame is denoted by omicron (black) and iota (silver). Omicron and iota serve as two flag poles, where we also show their respective flags. In order to see the flags, find the arcs in the x direction that move with omicron and iota during a series of transformations. The spin-frame is in a vector space over complex numbe...
A Reaction Wheel Unicycle Robot
Просмотров 18Месяц назад
This morning, did a few desktop runs with configurational modifications.
The Reaction Wheel Angular Acceleration in Controller Feedback
Просмотров 57Месяц назад
The Reaction Wheel Angular Acceleration in Controller Feedback
Preventing Parallel Transport from Being Interpreted as Rotation
Просмотров 312 месяца назад
Preventing Parallel Transport from Being Interpreted as Rotation
Experiencing Translational Acceleration as Rotation by Inertial Sensors
Просмотров 532 месяца назад
Experiencing Translational Acceleration as Rotation by Inertial Sensors
Real-Time Transformation of the Hopf Fibration with Robot Tilt
Просмотров 122 месяца назад
Real-Time Transformation of the Hopf Fibration with Robot Tilt
Gravitational Acceleration for a Robot in Free Fall
Просмотров 162 месяца назад
Gravitational Acceleration for a Robot in Free Fall
Full State Estimation: Gravitational Acceleration and Rotary Encoders
Просмотров 422 месяца назад
Full State Estimation: Gravitational Acceleration and Rotary Encoders
The Direction of Acceleration Vector
Просмотров 2,5 тыс.2 месяца назад
The Direction of Acceleration Vector
Visualizing the Acceleration Vector of Gravity
Просмотров 1852 месяца назад
Visualizing the Acceleration Vector of Gravity
Running Based on the Combined Static and Dynamic Acceleration Vectors
Просмотров 2443 месяца назад
Running Based on the Combined Static and Dynamic Acceleration Vectors
The Digital Mirror of the Unicycle Robot
Просмотров 5193 месяца назад
The Digital Mirror of the Unicycle Robot
Stunning. 10/10 would spin-vector again
Looks super cool :)
Idk whats happening, but ist cool
I'm enlightened Thanks
You’re welcome.
This is so nerdy. Keep going though it has undeniable rizz.
this looks kind of weird, why do the vertices jerk around like that, and why is the icosahedral envelope so distorted?
The 600-cell has 120 vertices. The vertices are in the three-dimensional sphere. 60 of them on one hemisphere and the other 60 on the other hemisphere. When you rotate the three-sphere, the 600-cell that is inscribed inside the 3-sphere rotates with it as well. You can see that each hemisphere looks like a doughnut and the two hemisphere are linked together. Also, there’re 1200 faces in the 600-cell. For showing the inner faces we change the opacity of the faces randomly to let light rays get inside and reflect from them. What’s more, the edges that cross the equator of the 3-sphere have been removed so that you can see where one hemisphere ends and where the other begins. During the rotation of the three-sphere the equator rotates too and that’s why the interlinked doughnuts roll on each other.
@@iamazadi oh, I get it now. is there some interpolation as well? also, it's very confusing to say "3 dimensional sphere" to mean 3-sphere, as a 3 dimensional sphere is a 2-sphere.
@@ziggyzoggin the rotation of the three-sphere is done by first parameterizing points on a great circle of the 3-sphere using an angle, and then interpolating between an initial and a final angle. Multiplying the vertices of the 600-cell on either left or right by a parameterized point performs the rotation. One has to extend what we know about the geometry of the 2-sphere to develop tools for working with the 3-sphere, because spheres of different dimensions share geometric features.
That’s great, but we can’t tell if it’s a constructed illusion or it’s own independent operator
One can prove the existence of connection one-forms using the same logic that Isaac Newton used to write his book: “The Mathematical Principles of Natural Philosophy”. So connection one-forms exist independent of us. However, in physics things have to come with the evidence of observation. The more the amount of evidence for something, the more likely that it exists. Connection-one forms appear in the Lagrangian of the standard model of particle physics. and very strong evidence supports its existence and role in the yang-Mills theory.
@@iamazadi I wasn't trying to debate a subject-object dichotomy of mathematical philosophy. We know mathematical conceptions change over time, and it's still up to debate as to whether or not anything exists independently of the subjective experience. However, I feel like you didn't answer the question. The point was what mechanism is used to generate this graph? Is the, "one-form," moving like an inch worm independently, or is it constructed as dependent upon the cartesian grid in which it is placed?
Good question! The connection 1-form depends on the metric that is defined on a principal bundle. You can check that both logically and numerically using Julia for example. As a definition, 1-forms take values from the tangent space at one point in the bundle and produce values in the Lie algebra of the fibers. But the metric also depends on the connection. So, we don’t know which one to start with in our computations, either way the two properties of a connection 1-form is the same and verifiable. Connection 1-forms are not unique and the way to verify whether an object is a connection 1-form or not would be to test two equalities. Let’s say that g is the fiber action in the bundle. First, the pullback of the connection by the right action of g equals the adjoint of the connection by g inverse. Second, vertical vectors in the tangent space are constant under the application of the connection. In other words, connection 1-forms eat horizontal vectors and produce zero. I’ve written a suite of unit test just to verify these two properties at the level of linear algebra. I’ve also unit tested the axioms of the linear algebra itself in a separate file. See github.com/iamazadi/Porta.jl/blob/master/test/hopfbundle_tests.jl and github.com/iamazadi/Porta.jl/blob/master/test/spacetime_tests/real4_tests.jl for example.
"The tallest mountain started as a stone."
Impressive Mr. Azadi 👍🏽 5:46
Thanks Mr. kamranifard
Impressive Mr. Azadi 👍🏽 5:46
Impressive Mr. Azadi 👍🏽
OMG! I think I just groked what you're doing! 😀
That's really cool. You should hook it up to some kind of plotter to show you the real-life orientation of the model on the computer, might be interesting.
Thanks for the input! We made the plotter and hooked up the robot for real-time visualization: Visualizing the Acceleration Vector of Gravity ruclips.net/video/ib1llkPrtsM/видео.html
Huh
works ok as long as your finger is on it
There should be a way to add the physical force that was exerted on the top of the robot to the control signal. Gathering data for a machine learning model is an objective.
It seems to me that the control loop of the top wheel is a bit lazy and sluggish. What others suggested, to add more inertia to the wheel could help bringing it back from a seriously tilted position, but keeping it in balance, it needs to finely and quickly react to miniscule angle deviations. I’d say, the dead band is too wide allowing too much tilt. Possibly the D term in the PID, but we can’t really see for sure as it either does not spin at all and falls then after a certain angle it tries with max. accel. and speed, but it’s too late then.
It makes sense because smoothing the tilt angle readings slows the reaction time and consequently widens the dead band.
I need a smoke and my 2 minutes and 40 seconds back after this video
Make the bottom wheel small and top wheel twice the size, and add few more nuts...
You have a lot of mechanical issues that make it harder for the controller to adjust the system stability, you can try a single flywheel first then you go for the second one, then you can apply sensor fusion technique later. try using better coupling system for motors and try motors with a well-lubricated gearbox.
You gotta adjust your PID values and add more mass on the top, good luck 🤙
I would ssy that you should bring more mass to upper wheel that it has more rotary inertia
Pretty cool! ^.^
when drunk and i need toilet
They don’t keep the comments up long enough. I don’t read that fast.
Beautiful
Great visualization
very interessing
Тень от руки сверху: "Это точно балансирует".🙈
The Goal of Balancing is accomplished in this video: ruclips.net/video/sR8kfuUdOo8/видео.html
considering it been made by simple matrials this is a fantastic work great job
Thanks
run! its alive
Needs more struts!
Why does it need more struts?
geometric algebra or topology?
Both
very cool
Useless fast animation and no real explanation Waste time
The Hopf Fibration Explained (A Math Explainer) ruclips.net/video/qZNTPCMM19s/видео.html
So true
Pretty neat! ^.^
Almost all the links in the description are 404.
Fixed all of the broken links in the description. Now, you can visit the links again!
@@iamazadi All better now, thanks!
Ah yes, I was just wondering
please i need links for books to bring to the subject
Try to find the books on the genesis library: libgen.is
Fixed all of the broken links in the description. Now, you can visit the links again!
Audio audio audio. Intolerable, please fix
Noted. Thanks for the feedback.
thank you! keep it up
You’re welcome!
what
The Hopf Fibration Explained ruclips.net/video/qZNTPCMM19s/видео.html
Weird spinor
Great Stuff! ^.^
Thanks!🙏
What was used to build this impressive visual?
Two software packages: Makie.jl and Porta.jl. Source code: github.com/iamazadi/Porta.jl
keep living
I smell inversion. ^.^
🔥 ^.^
Animation is too fast.
Now that’s what I’m talking about! ^.^