What channels come under "et al."? Looking for similar creators.

@@triyanbhardwaj934 Fraser Cain (cosmology), ScienceClic(GR, physics), Isaac Arthur(futurism), History of The Universe (ASMR Space stuff), Wondrium (general & other science)

@@RecoilTechno Thank you :) Love HOTU btw

What did you learn here that you didn't know before?

@@trout3685 I don’t really consider myself as knowledgeable on any of the subject matter, but for instance, this particular video features a more in-depth look at the mathematical aspects.

I too would _love_ to be able to comprehend the inhumanity difficult math behind Black Holes, S.R. and G.R.

@@artdonovandesign Special relativity is pretty simple mathematically. You only really need to know algebra to understand it, and preferably also some basic differential and integral calculus, but it's not needed to understand the basic concepts.

I'm the opposite lol You can have a subject explained in physics terms and I understand nothing. The same subject explained in abstract mathematical terms and I have a much easier time of understanding it.

@@artdonovandesign "Inhumanity" is a noun. You can't use it as an adjective. Maybe "inhumanely" difficult mathematics. But it is strange to use that word here. Math doesn't have any motive that can be described as being inhumane. You could use the word "inhuman" maybe... If you want to use it to describe how "difficult" the math is would become "inhumanly difficult math". But who cares we know what you mean XD

@@Ernthir "Inhumanity is a noun". You are perfectly right. But the entire statement using "inhumanity" is also wrong semantically, and this semantic, and, I would say, methodological fallacy is even worse. Humanity is the attribute of the human. Frankly, every time I see the word "math" instead of "mathematics", I don't expect anything related to real mathematics. 🙂

Well...he didnt completely invent it, there is a field of mathematics that deals with all this called differential geometry that has existed since before einstein was even born, he used it (with the help of several other mathematicians) to formulate his brilliant ideas and make quantitative predictions

Unfortunately, the concept of spacetime is wrong 😞

@@peterdamen2161 really?

@@stomas4744 Really!

@@peterdamen2161”I am withdrawing my theory on account of dr. Prof. Peter of KZfaq comments expert opinion.”- Abe Lincoln

I've heard explanations claim that space and time flip inside the event horizon, which would actually be fairly consistent with a rotation like from i.

Check out PBS Spacetime channel. They've done a couple videos on that.

ScienceClick and Dialect are hands down the best non-uni level physics educational channels.

This embedding was invented by Rickard Jonsson, PhD, as far as I know. Can not give you a link, because YT deletes those comments instantly. He generalised this embedding to include the interrior and to the Reissner-Nordström-metric. I think that it is impossible to generalise it to Kerr or Gödel or anything 'rotating', but RN is very similar to Kerr.

The final boss of black hole visualisation/understanding is Donald Marolf's embedding into Minkowski. In my opinion, that is much better than that 'space is falling'/Gullstrand-Painlevé approach. I wanted to make a video on Donald's embedding, but am I lazy man :/ . I hope that eventually either you or maybe Dialect will make a video about it, to show its beauty to the greater public.

From a Linear Algebra perspective, I think its transforming the Inertial coordinate vector relative to a change of basis. Then viewing the inertial coords in the new basis. Dr. Trefor Bazett has a video about it here kzfaq.info/get/bejne/qZp3dpmr1LuwmWQ.html

Yes, that was a crucial beat, and it was a bit fudged. But otherwise excellent.

At 9:42 is the ruler really seems to distant observer contracted when when proper distance increased? Isn't he mistaken?

Thank you for watching and glad it helped your understanding!

I guess the last episode will also end in a cliffhanger 'cause at some we stop knowing what the duck is happening

Even with sound off, subtitles on, this was beautifully clear. Well done.

Einstein's theories (both SR and GR) are 50-50 mix of reality and illusion. Reality of time dilation, illusion of objects and space bending. You might need to check story on Medium: Illusions of Einstein and Rotary Blades Curving

Most meaningful information? Really? What is so meaningful? What did you learn that you didn't know before?

@@trout3685 This is what I said under DrBecky's video called 'JWST confirms MOST DISTANT galaxy!' _"@Dr Becky - did you see Dialect's vid 'The geometry of a BH'? It's interesting. What I learnt is: Greenland's too big on some maps but you can change it to the correct proportions by saying "shrink it here by a factor of 3.5 & here by 1.5" etc. In relativity there's a thing called a metric tensor which contains those destretchification numbers e.g. 3.5 & 1.5. Around a BH, space's stretched too much so if I am holding my banana, it'd become a spaghettified banana & the metric tensor says [your banana's stretched by a factor of 2000]"_

You do not have to be PH.D'd t or ordained by some university to make an amazing discovery. Follow your heart and your dreams will come true.

@@trout3685 bro what are you on about lmao

At 9:42 is the ruler really seems to distant observer contracted when when proper distance increased? Isn't he mistaken?

Thank you for your support and appreciation! Hope we can continue to illuminate the mathematics and philosophies behind these advanced topics in physics for y'all in the future!

Right 🤣

Can you explain what piece this video added and what pieces were in place before this video?

Do you always tell your car “great work” for functioning? Cause telling an AI channel “great work” is essentially the same thing.

Is it really that much more clear? Things go into the black hole. What did you learn here that you didn't know before?

awsome comment dude.

Because out there are not so many "smart" people who really enjoy math Luckly I am not one of them :)

Check out PBS Spacetime channel. They have a few of those.

Watch the SciencClic episode of how Time and Space switch when you enter a black hole.

Anyone who does offer such a visualization is basing it off of unfinished data or a broad generalization based on our understanding of physics, considering the physics we know breaks down past the event horizon. It'd be like asking someone to create a visualization of God, which is impossible.

if he can, he get the nobel price 😀

@@Lord_and_Savior_Gay_Jesus I thought the inversion of the spatial and temporal coordinate past the event horizon was part of that visualization. Is that an incorrect assumption?

it's just a sphere, the "curvature of spacetime" is not a real thing

Is it enlightening though? All of the spacetime curvature stuff has made no sense to me. I get the impression we need to completely rework our language for any of these concepts to be explained accurately.

@@elio7610 Or... just learn the language of mathematics.

@@flambambam3578 Fair point, i guess, still, it seems like language has been failing to keep up with everything. You can argue that is what math is for, yet people still try to describe stuff in english. It seems like an issue that extends beyond science, langauge failing to adequetely describe reality and leading people down all sorts of weird logical paths to argue over fictitious concepts. Apparently, people treat language as an unquestionable tradition and claim it can't be improved. Maybe there is no perfect language, there certainly is language that works better for specific uses than others though. I am convinced language is being treated too much like a religion when it could be more practical to treat it as a technology.

@@elio7610 Semantics can be tricky in that regard. The interpretation of verbal language varies per interpreter, and mathematics helps remove that ambiguity. It works well within its own domain, but the translation process between the mathematician and the layperson reintroduces that ambiguity. One practically has to specialize in both mathematics and verbal language to effectively and correctly portray the concepts being discussed. For me, it's easier to develop an intuition for math than it is to put that intuition into words. It's almost like describing a sense to someone that has never experienced it, except we created a new sensation and are now attempting to describe it using previous knowledge. It's hard to understand because we aren't hardwired to understand it.

same, I could understand it until I realized that... there is nothing to understand, you can't understand something that is not real

Thanks for watching, and glad you enjoyed it! (And technically, we were imprecise when we used the term "manifolds" in the plural -- it's all actually a single manifold. If you change what radial line you are on, you would sort of "hop" from one rolling sheet to the next.)

To a outside observer it's exactly what happen, but to the free falling to the black hole observer he would travel a normal distance, while the rest of the universe fast foward in time up to the end of the universe... then die

You are not wrong. From the POV of a distant observer, nothing ever reaches the event horizon... it slowly approaches it, and dims as it redshifts and asymptotically approaches the horizon. It's not that it's just infinitely far away... it spacetime after all. It's also infinitely in the future. From the POV of the object falling in it takes a finite (and short) time to reach the horizon and whatever is beyond it. Consider the transformations he shows to convert between inertial and orbiting (accelerated) observers in the video. In doing that rotation, and combining it with curved spacetime, the space and time dilations undo each other, and you get a finite distance and time travelled by the falling observer (i.e. they are reciprocals). 2D space is not 2D spacetime: imagine each ring has a vector between 0 (at the distant observer) and pi/4 (tip) attached to it to represent the Lorentz rotation applied in order to keep the orbital lines parallel in the diagram. This introduces the "twist" he shows for inertial observers that fall in.

But what about the stellar core that formed the black hole? The matter at the center of the star would already be beyond the event horizon because it existed there before it formed.

@@CleverNeologism (and @Greathigo ) So there's this idea that an outside observer (let's call her Alice) never witnesses anything cross the event horizon, but an in-falling observer (let's call him Bob) crosses it. I have a followup question. Suppose, long after Bob has already jumped in, Alice also jumps in. As we said, in-falling observers cross the event horizon. So Alice must cross it. But now, she also must observe Bob cross it at some point before she herself does, since Bob jumped first. Is this so? If so, it would suggest that there is some non-zero distance from the event horizon at which you actually can witness things cross into the event horizon. Also I'm not sure I understand what rings you are referring to. Are you talking about the green rings corresponding to time axes at individual "points" in space?

@@flambambam3578 My guess would be that, at least from our perspective far outside the black hole, the whole stellar core would be smeared on the black hole surface. Any two particles in the stellar core have an event horizon, right? From our outside perspective it would take forever for one particle to cross into the event horizon of the other.

Doug Demuro's tongue is huge?

Recently i have been thinking about all the simplifications and visualizations i see in explanations of phenomena, i am not sure if am learning or being mislead. The issue is trying to teach complicated concepts while skipping all the complicated details, the question is: Does any of it communicate an accurate and useful explanation or is it more often misleading people into believing something wrong? Language use can be just as misleading as visuals, so i do not think visualizations alone are the sole concern.

If I got right... The inertial object moves on r direction following the curvature of spacetime, in this case the distance r decreases as it moves on time direction. The only way to keep a constant r distance in this curved spacetime is to accelerate in the opposite direction. The non inertial observer is not necessary to explain the motion of the inertial object, it is just to show how the inertial object moving on the curved spacetime looks like a free falling object from the point of view of a stand observer in r direction.

Hey, thanks for watching! You're correct to point these issues out. One of the first things we learn in General Relativity is that objects follow their natural geodesics on the curved spacetime manifold -- but clearly here the inertial objects do NOT follow geodesics. The typical answer most physicists will give is that because we have used a euclidean surface to represent a hyperbolic one (spacetime distances involve a negative sign) geodesics will take a direction "opposite" to what we expect. However we suspect that the mismatch between geodesics and inertial worldlines are more related to the fact that this surface is constructed from the accelerated perspective (which would constantly introduce an "offset" to the manifold's straight paths, making them non-straight). Many physicists, even the highly credentialed ones, don't understand acceleration in relativity very well, so it's possible once we re-construct the manifold from an inertial perspective, geodesics and worldlines will match up. We hope to resolve this issue and provide a fuller explanation in future videos. As to why one needs to accelerate to maintain constant radial distance, we suggest checking out our video "The Sky is Falling Up" for more on that.

@@narfwhals7843 In the original script, we addressed this issue, but for time and flow and comprehension purposes, we cut it. Mainly, because it involved a whole discussion about acceleration in GR, and, well, you know how well that's gone over in prior videos. It's not unfair to accuse us of being misleading here, as the mismatch between geodesics and inertial worldlines here is definitely a major omission and source of confusion. However, unlikes *some* channels, we are fully prepared to address why we made such an omission, and moreover, do intend to clarify it in future videos.

@@dialectphilosophy Thank you :) Now it's much clearer. I rely more on intuition because I don't find enough time in my life to study physics properly. So when you did that transformation there, my brain stopped.

there are so many dialects nowadays

especially that you understood, what dialect is about in scientific circles is not important

😢😅❤

😂😊😅

So we are not speaking of a linguistical dialect or colloquialism of sorts. What we are really discussing is the speed of light and how exceeding it, may cut you off from the laws of the known universe, or exceed the laws that allow you to perceive those laws visually or mathematically. Personally I think black hole is large fork that spins space-time around like spaghetti, forming large twine like ball of linguini-like universe all rolled up small enough to exceed the laws of regular universe. If universe was a large quilt these would it be spots that God jam a fork into and twist around to hold things in place like tacks or to be like drain pipes for the universe that empty into impossible 4 dimensional spaghetti twirling forks of universe!

The trampoline illustrations, should have the membrane pulled toward the center of mass, not pushed away from it. (sigh)

I did too, but I didn't reach the same conclusions