Wormholes, Cosmic Strings, and Gödel’s Universe
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- čas přidán 11. 08. 2023
- The real science of time travel. Covers topics such as the Transactional Interpretation of Quantum Mechanics. Also discusses time travel using Albert Einstein’s General Theory of Relativity. My Patreon page is at / about
- Věda a technologie
I often notice many people expressing complaints regarding the inclusion of music in your videos, this might be the reason behind your decision to remove the music. However, I am among the few who truly adore the music you incorporate. These melodies, combined with the concepts you present, synergistically create a profoundly pleasing experience for my mind. Another outstanding video!
Seconded. I miss the music, it was always so beautiful. Especially the first video about relativity which was animated in 2D, I actively listen to that music because it gets you lost in this new world of physics.
I agree. Their music was very pleasing.
Thanks for the compliments, everyone. Music will return in future videos.
@@EugeneKhutoryansky The allemande from J.S. Bach's french suite no. 2 is my favourite
@@EugeneKhutoryansky Yes please! The music was part of what made me fall in love with your channel.
Your videos enlighten humanity ,
Thanks for the compliment.
Thank you, Eugene your videos helped me a lot to better understand the world we live in!..
Thanks. I am glad my videos have been helpful.
Whenever you go, then you are.
A+
Yep. Especially now. 😅
Eyy that was said by Lao Ce wasn't it? Except, with "wherever" and "there"
No classic music? My inner Pavlov dog is disappoint. When I consume Eugene's physics videos I need classic music. When I hear classic music I expect physics video. (Last time it happened to me, I was in supermarket and took me second or two to realize no physics was incoming.)
XDDD
I prefer the videos without a background music
Great video😊 I always show your videos to our students at school.
Thank you!
Thanks! I am glad you like my videos.
That would mean that even after heat of the universe, some weird timetravalers could make a colony at the end of the universe and casually live there.
it would be incredibly hard tho, as they would need to make a biome where the system does not lose any energy to the outside, otherwise they could die due to no energy being available to do stuff.
@enatrage2083 They need to lose energy to the outside, otherwise the temperature inside the biome would keep increasing until they all die. As for running out of energy, they could bring enough nuclear fuel with them that would last many lifetimes.
Interesting concept, though emphasis on “weird” time travelers. Maybe a civilization tries to escape from a cosmic horror by waiting it out until the heat death of the universe by closely orbiting a black hole. Along the way you gather up enough hydrogen to power fusion generators for millions of years. Like a City of Ember situation
so all time travelling civilizations might have a colony at the end of time... they could even meet, but then they must agree on the time and place
@@_layman_ in addition to the comical challenge, it’s a massive logistical challenge as well 😂
It's also important to point out that time travel through wormholes (actually any time travel not involving parallel universes, from an eternalist point of view) does not change the past. It simply inverts causality, with future influencing past, which is not paradoxical on its own, at least from a "superdeterministic" point of view. A perfect example of wormhole-like travel in pop culture is time travel in Harry Potter and the prisoner of Azkaban: nothing changes, everything had already happened.
The Harry Potter Proper also has this exact type reverse causality.
The problem is what if you go back in time with the explicit intention of changing something that you know occurred. There is no explanation as to what would prevent you from doing so, yet the past can't change, hence the paradox.
@@EugeneKhutoryansky Solving the paradox requires in fact superdeterminism.
The paradox is because we are used to think of our will as quite independent from the rest of the universe: if I can think of doing an experiment, I can do it in principles, so the outcomes must make sense. If we adopt superdeterminism there is no paradox, since I can't determine my future will or possibility of ending the experiment, and so I can't assume that any outcome which I now think possible will still be possible, even if I can't determine the causes of the impossibility.
Let me rephrase: There is no explanation as to what would prevent you from "thinking" of doing the experiment. Surely, in the history of the universe, it is plausible that at least some sentient being could think of deliberately changing the past. I understand the point you are trying to make, but I hope you understand the point I am making.
@@EugeneKhutoryansky Yes, yes, I understand, we agree on the non-superdeterministic point of view. With the superdeterministic paradigm we can conclude the "machinery" of the universe will prevent you from changing the past, so time travel does not lead to paradox. Without the superdeterministic paradigm we can conclude time travel is not possible, since it would lead to paradox (the whole machinery prevents you from traveling through time, the impediment is more general, e.g. "you would have to break continuity").
I know the two kinds of impossibility are fundamentally different, hence they belong to different paradigms and interpretations of physics.
Dice cat is fearless
I love your videos. I know I only watched 2 of them but I already fell in love with it. The unsettling vibes, the enlightened music, the monotone voice and the 3D animation are an amazing combination to make a fascinating video about what physics can truly be. Your videos feel otherworldly, wich makes a perfect statement about how special and weird our world truly is. Love your content.
Thanks for the compliments. I hope you enjoy my other videos too.
Another awesome video! Thanks!
I am glad you liked my video. Thanks.
In a period of 3 weeks, I showed 13 of your videos to my daughters aged 7, 10 and 12 and this had profound effect on their personalities! After a late night physics discussion party that lasted until 8am, we all came to a conclusion that Eugene's videos create the "feeling of physics" - a deep fundamental understanding of the nature of Reality. With my explanations and Pause/Play all of my 4 kids are your hardcore fans now 😍😍😍
I am glad that your daughters enjoyed my videos and that my videos made them interested in the subject. Thanks!!!
Eugene is cool
Thanks.
thanks for the sharing
You are welcome and thanks.
A new physics anime episode!!! Exciting!!! Great topic
Thanks. I am glad you liked the topic.
I like the way the girl with the messy red hair at the end is obviously thinking 'I have made a terrible mistake. Who knew that travelling to a distant future where all the stars have burned out would be so lonely?'
always listen to ur videos before goin to sleep expecially the one about multiverse, thank you
I am glad you enjoy my videos.
I LOVE THE MUSIC AND YOUR VIDEOS
Thanks!
Thank you sir🥰
You are welcome and thanks.
Excellent video.
I am glad you liked my video. Thanks.
Thank you always for your amazing videos! I have a question about time travel using Kerr metrics. In the Kerr metric of the valid range (a ≤ M, where c = G = 1), I heard that the inner horizon of the Kerr metric is the Cauchy horizon, and in that inner region the CTC exists & time travel is possible. If so, assuming that the Kerr metric in the range a > M (with naked ringularity) is possible, would CTCs exist there as well? (If so, time travel is possible simply by creating a Kerr black hole with a naked ringularity, which is exciting.) Or, is the Cauchy horizon always required to create a CTC in asymptotically flat spacetime? Thank you!
Arvin Ash made a video on that, type "going back in time with the use of rotating black hole" or something like that and You'll find it
As always awesome 🙂👍
Thanks.
Appreciation of these concepts is how we come to terms with our own mortality. Each perspective offers a realistic scenario for eternal life.
Excellent
Thanks
Glad to see a new full length video. Good topic and great video👍👍 Thanks 😊
(What about debunking Dialect videos? - 😉)
Thanks. I am glad you liked my video. I am not going to make videos debunking other people's videos. I think leaving my comment under their videos is more than enough. Thanks again for your support!
@@EugeneKhutoryansky You did comment their video? Which one?
Awesome thank you for your work. Bring the music back too please!!
Thanks. The music will return in future videos.
love from India, 🇮🇳 your vedios is very helpful to understand the electromagnetic subjects in engineering.
Thanks. I am glad that my videos on electromagnetism are helpful.
@@EugeneKhutoryansky can you come in live on you tube ,we want know about you and more so that we directly ask our doubt and question that's was helpful for us . 😁.
Disclaimer: This video was recorded in reverse order while going Backwards in Time
Awesome again
Thanks.
@@EugeneKhutoryansky
Can you tell us about the difference between emf and potential differece
Have you seen that paper that proposes dark matter is time-dilated mass in Minkowski space?
Thankyou your videos helps alot to teach phyiscs at college level. Respect from pakistan
Thanks.
Awesome as always. Love the rock and the dinosaur 😂
Thanks.
The cosmic strings and wormholes are hard to reach but it helps you to time travel to either past or future
Be careful to change the past and it creates paradoxes
Thank you for confirming my years-old theory that 'GRAVITY CONTROLS TIME'
Thank you for many your videos.
They are very useful for me.
By the way, would you make a video about abc-αβ transformation and abc-dq transformation?
I know you are so busy but I would like to you make the video and I want to understand Three-Phase - Two-Phase transformation.
I’m sorry for my poor English
Regards
Thanks for the compliments. I have a video on 3 phase power at czcams.com/video/EzDs6jPrpFw/video.html
🔴 As usual - keep it up!
Best guy on youtube
Thanks for the compliment.
It may also be possible to look into the past by using a black hole as a mirror
Yep, excellent point
Eugene can u please make videos of S. Ramanujan on his mathematical equation
I am not familiar with him.
It is in my understanding, that even though we haven't observed them, there's a wide consensus that cosmic strings most likely do exist?
enlightening
Thanks.
Interesting. An episode on transactional interpretaion has now become a natural demand from us viewers.
I cover this in my video "Philosophical interpretations of Quantum Mechanics" at czcams.com/video/XQ25E9gu4qI/video.html
If speed and gravity can send you to the future then what happens if you combine the two. Like going near light speed close to an event horizon?
Thank you very much, Eugene! Now I understand why quantum entanglement doesn't violate causality, even though information is transmitted faster than light.
Thanks.
Quantum entanglement doesn't violate causality because it's just local correlation. No information is transmitted.
I could take two pieces of paper, write "1" and "-1" on them, hide them inside identical boxes and move them light years apart. Those boxes are "entangled", because once I observe any of them (look at the paper inside), I can immediately deduce what is written on the other, because the sum of the numbers equals zero.
@@henrycgs It is more complicated than that. I explain this in my video "Quantum Entanglement, Bell Inequality, EPR paradox" at czcams.com/video/v657Ylwh-_k/video.html
I miss the music! But great video anywaus Eugene!
Thanks. The music will return in future videos.
Try fresh story on Medium
Illusions of Einstein and Rotary Blades Curving
that separates the wheat from the chaff.
In the Futurama Episode ‘The Late Phillip J Fry’, the Professor made a Time Machine that could only travel forward in time. Unfortunately they travelled to the year 10,000 (7000 years after their time in 3010), they then spend the rest of the episode trying to travel forward in time in the hope someone had made a backwards travelling Time Machine, they did find a time where someone made such a machine but just as they were about to close the deal, Bender made the Time Machine move forward to just before the heat death of the Universe. Believing that there was no way to undo what had just happened: Fry, the Professor and Bender decided to make time move forward to witness the heat death of the Universe, then just after that happened (note that inside the Time Machine it was a few seconds but outside it might have been many billions of years) the Big Bang repeated itself creating a Universe identical to the last one. What I have just explained is in line with the Theory Goedell proposed which was discussed in 3:09.
Boring.
But why would a big bang occur after the heat death of the universe? Big bang is the state of lowest entropy and heat death is the state of highest entropy, and entropy only increases as we know it.
It’s a cartoon
The Simpsons and Futurama have predicted the future in many instances tbf.
@@EdwardChan.999 czcams.com/video/vvkIF0NlIzA/video.html
Your content is very beautiful❤
Thanks for the compliment.
Another brilliant video my mentor, I previously had no idea of cosmic strings... Recently NASA discovered a Galaxy with no dark matter at all.. That was mind blowing... How can a galaxy have no dark matter at all? That's a very intriguing question... Anyway my mentor please make a video on gravitational wave background that scientists recently discovered using pulsar timing array... It would be very amazing if you made a video on gravitational waves and most importantly relativity of rotation.. That would be great and amazing..
I am glad you liked my video. Gravitational waves and relativity of rotation are on my list of topics for future videos. Thanks.
By the way, rotation is not relative. That is, you can tell if you are rotating, independent of any reference frame.
@@EugeneKhutoryansky Lets suppose an observer is in circular motion in a circular path around a centre point with relativistic tangential velocity. Ome thing is confirm here that he will feel a gravitational force pulling him towards the side of spaceship that is not facing the centre of the circle. The thing that I can't comprehend is that how will he see the outside universe i.e., how does the view of outside universe appears to him? How will his spaceship appear to an observers who are at rest relative ro the centre of the circle? One observer standing in the plane containing the circle and the other observer standing at a great distance from and exactly over the centre of the circle, perpendicular to the plane containing the circle... I hope you understand this visually... Now what will all the observers see?
@@EugeneKhutoryansky My mentor is my above reply visible yo you?
I assume you mean that he is in a spaceship continuously firing his rockets to accelerate towards the center of the circle, to maintain a circular path despite the fact that there is no massive body at the center. I may make a video on this. Thanks.
Maybe mass is a state (like solid, liquid, or a gas) of energy and time changes it back to energy.
this is so true ,Now we just have to worry about ?
Idk how to explain this in a CZcams comment but time travel backwards is not possible, only forwards. Time is just a unit of work or can be thought of as a measurement of entropy. Each passing moment is 1 set of calculations done within space-time. The more "atoms" of space-time are condensed (meaning matter/energy and thus gravity), the more calculations are required to pass thru C and thus distance is converted to time, which slows down the observer in space and time (eg time dilation, or contraction rather, around massive objects especially black holes). If the "atoms" of space-time are not condensed (eg the vacuum of space with minimal/no matter in a region), then a massless particle does not slow down and without mass, all energy is used in the distance axis and particles can approach (or travel at) C. Time therefore can be thought of as the relationship between matter/energy, C, gravity vs distance, and the ratio between these interactions. Entropy dictates that time can only move forward, never in reverse, regardless of what the equations of QM incorrectly imply. And I suspect that on a small enough level, even space and time itself have a relationship that breaks down, however it can still be thought of as unified in the sense that each unit of time corresponds with a change in the units of space "atoms". I hope that makes sense the message is conveyed but happy to clarify.
I do have some quires...how to reach out ?
Any chance you would be interested in discussing the theories of David Deutsch or Seth Lloyd?
I am not familiar with them.
@EugeneKhutoryansky Here is a lecture by Professor Seth Lloyd. His work builds on the work of David Deutsch.
czcams.com/video/yCQ_3qE6SmQ/video.html
@@EugeneKhutoryansky Their work is on the quantum mechanics of closed time-like curves. It's a fascinating topic.
Long time no see channel
I made several "shorts" videos recently. You can see them on the "shorts" tab on my home page.
Wait... narrated by Kira Vincent? As in Kira Vincent-Davis?
GÖDEL WORMHOLES HELL YESSSSSSS
07:10 Было бы интересно узнать, что там в конце всего и будет ли новое начало. 😏
Just wait and see. 🥴
wow
4:20….See this is where sense evaporates…in one statement we get cosmic string of “sub atomic width” with such mass it is auto “black holed” out of our universe…in the next mouthful she’s talking ‘flying around it in a figure eight pattern”. Ok, I’m down with thought experiment, they are fun, but this ranks with time travel through a black hole so small you’d be instantly turned into fly swat.
hi osaka 💖
Everybody forgets the great filter prevents all this from occuring. Species will never get past the oil tech tier.
👍
Where the tunes at?
At what speed do you begin to appear slower to the observer? At what speed do you start to arrive later than expexted?
Going really fast actually= going really slow. (Observer says "what took you so long?"
Therefore moving really slow must equal= arrive faster aka sooner than expected (or before you left)
By our current understanding negative speed is not possible. So what is broken? Probably understanding of what happens when we move through spacetime.
Moving that fast creates a field around you that shrinks you in spacetime. Think how long a 10 mile walk is and then how long that seems to an ant. Relatively based on size that is a many more "miles" to that ant.
So my theory is that if you have something spinning near light speed around you creating a circling field of this shrunken spacetime but you sit within and just outside the field technically you are much larger in spacetime relative to the outside environment.
If you then independently move at a high rate of speed within that field you will technically be moving at faster than light speed compared to the shrunken spacetime and the interaction of those two fields will mathmatically generate an artifical negative speed and move you backwards in time so when you cease movement you will be in the past.
😮
Maybe there are things that routinely travel back in time and change the future, like in the paradox. And it happens all the time, as a property of our universe. Only we can't notice it because we're changed, too, every time it happens.
Quantum entaglement is independent of space, thus time, so time travel of information is atleast possible
No music? : 0
epic
Thanks.
Advanced physics only apply to people who know how to use them. Not us I'm afraid maybe never us. It's your right as an intelligent being to know and inspire too learn while our understanding is convoluted the whole galaxy is too.
I watched a video where they said Wormholes are theoretically possible with maths. Then how can you say Wormholes doesn’t exist?
Yes, wormholes are theoretically possible in the mathematics of General Relativity if you have something with the negative energy density to keep the wormhole open, and if you are OK with time travel to the past. There are many things which are mathematically possible which don't actually exist in reality.
¿What's in a NAME? Everything
The rotating universe is very near impossible.
🤔
Going back in time means lowering the entropy of the universe. How can wave functions extend into a more ordered state, while also extending into a less ordered state? I feel like us scientists need to update our language. There is no future and past, there is more ordered state (past) and less ordered state (future). We don't want to travel back in time, we want to travel to a lower entropy. Same thing, but more to the point. Time is all about entropy.
Forward ever, backward never.
I honestly don't think there are any paradoxes at all regarding traveling back in time. Paradoxes emerge from us simply not accepting that the flow of time is merely an illusion perceived by those who live within it. Try to look at the universe from the outside, as a 4D object. Key idea here is that this object is unchanging. There are no paradoxes, only objects influencing the past in precisely the same way we define the past objects influencing the future - when their spacetime lines cross. It's impossible to change the past, because the past already happened... and so did the future. I could shoot a bullet that goes back in time, trying to hit me in the head before I fire it. If I didn't get hit before I won't get hit now, so the experiment would never succeed. I could go back in time, and shake the hand of my younger self, telling him that I remember the time my own future self did the same thing. Sure, it's a loop, but the only thing broken here is human intuition.
The only thing that could possibly be called a paradox is the bootstrap paradox, in which some object or information is stuck in a time loop, with no origin. Simple answer is these would just not happen, because they would violate the conservation of energy. Additionally, an object in a time loop would be infinite years old, which, yeah, I can't see how that would work.
Es increíble que a estas alturas del desarrollo de la humanidad sigan vigentes teorías tan absurdas. El tiempo es un invento humano, es imposible viajar hacia adelante y hacia atrás en el tiempo. Los físicos modernos son el equivalente a los brujos de la antigüedad y el público es el mismo que antes, extasiado con tales aberraciones.
Why go to the past, why not create a portal to another reality where the universe is younger
Two comments: One (very brief ) segment of this video, time travel to the past shows a dinosaur, implying that you could travel to the time of the dinosaurs. This is not possible, as several physicists have argued, unless a "portal" already exists in the past. For example, in the case of using a wormhole to travel to the past, one end of the wormhole must already exist in the past for the traveller to exit from. This implies, as people like Hawking and Thorne have mentioned, that you cannot travel to the past before the time machine was built. For example, suppose you invent a time machine and turn it on on Monday. You can't use it to travel three weeks ago into the past because the time machine didn't exist then. Another difficulty is the following. Both Hawking and Thorne showed that a time machine will self-destruct at the moment it is turned on. (The reason are subtle, and a good discussion can be found in Thorne's popular book, "Black Holes and Time Warps: Einstein's Outrageous Legacy".)
If wormholes exist, then there is no reason why one end of the wormhole couldn’t exist long before the dinosaurs. Also, if you use two cosmic strings to do your time travelling, then you can end up anywhere in space-time, at any time.
@@EugeneKhutoryansky As to your first point, the wormhole would have to have been built, presumably by some arbitrarily advanced civilization, prior to your using it. So you could imagine a scenario in which a wormhole time machine was built millions of years ago by some alien race, humans happen to find it, and then use it to travel millions of years into the past. However, you still can't travel to a time before the wormhole time machine was created. In addition, then you still have the self-destruct problem I mentioned before. Of course, one could always argue that a sufficiently advanced alien race could find a way to get around that problem. As far as your second point, what you say about cosmic strings is incorrect. Hawking showed, in his "Chronology Protection Conjecture" paper, that Gott's cosmic string spacetime already has to have closed timelike curves , i.e., "time loops, in it at infinity. Hawking's argument on this point has nothing to do with his CPC, e.g., exotic quantum effects, but relies solely on classical general relativity.
The wormhole would either have to be created a by an advanced civilization, or it could be a naturally occurring wormhole, if such a thing could exist. As for your comment about time machines self destructing, I am not sure what specific argument you are referring to. If you are referring to the fact that we need a negative energy density to keep a wormhole open, we just have to assume that something like exotic matter exists, which has a negative mass-energy density. Regarding your comment about cosmic strings, I am not familiar with Hawking’s argument that you referred to. I would just reference the following link from the Anderson Institute regarding cosmic strings, which claims that this can be done. www.andersoninstitute.com/cosmic-strings.html
@@EugeneKhutoryansky As to the first point I agree, part of which I said as much in my reply. However, that does not address the other points. I made. As to this point,
>> As for your comment about time machines self destructing, I am not sure what specific argument you are referring to.
The argument is rather technical and involves the circulation and build up of vacuum fluctuations around the closed time loop when the TM is first turned on. The argument is too technical to address in a short comment, which is why I directed you to Thorne's popular book (see Chp. 14 of that book). As to your point:
>> If you are referring to the fact that we need a negative energy density to keep a wormhole open, we just have to assume that something like exotic matter exists, which has a negative mass-energy density.
No, these are separate issues. As a side remark, the laws of quantum mechanics do allow, indeed predicts, the existence of negative energy, but those same laws also severely restrict what you can do with it.
As for the cosmic string argument, here is a quote from the introduction of Hawking's CPC paper:
"In particular, this implies that if no closed timelike curves are present initially, one cannot create them by warping the metric in a local region with finite loops of cosmic string. If the weak energy condition is satisfied, closed timelike curves require either singularities (as in the Kerr solution) or a pathological behavior at infinity {as in the Godel and Gott spacetimes)."
The Gott spacetime is the cosmic string spacetime. "Closed timelike curves" are time loops.The "weak energy condition" says, very loosely, that negative energy densities are prohibited. Hawking is saying that if you start out by trying to build a time machine in a finite region of space (more accurately, spacetime), you can't do it without negative energy. Although as I said, although QM allows negative energy densities, cosmic strings have positive energy density. There is no negative energy density anywhere in Gott's cosmic string spacetime. If the weak energy condition is satisfied, then funny things have to happen at infinity.
Hawking proves all this using classical general relativity, e.g., without having to invoke quantum gravity. The quantum arguments come later in the paper.
As to the reference you cite, I went to their page. This is one of the statement I found in the "About Us" section:
"Our primary mission is the development of time-warped field theory, its application and ensuring the ongoing development of time reactor system design concepts and capabilities."
This clearly indicates that they are not credible. One has to be extremely careful about where one gets information on these kinds of exotic topics, as you can find people and organizations. There are all kinds of wild claims made about things. that's why I suggest books written by credible scientists.
Regarding the cosmic strings, I was referring to infinitely long cosmic strings in an open universe. I don't know if this makes a difference to the argument you are sighting, as I am not familiar with it. As for the credibility of the link I provided, I have heard this from many other sources too, so they are not the only ones saying this.
First :D
Yes.
Quantum Entanglement does NOT involve the transfer of information faster than light. There aren't two separate particles. Its a superposition. A SINGLE wavefunction.
It is a single wavefunction which supposedly collapses everywhere simultaneously, hence transmitting information faster than the speed of light.
just teleport bro. way cheaper
4:58 traveling faster than light is possible, but you cant accelerate something to the speed faster than light, and those are 2 different things.
Im not convinced that time is an actual thing.
🤣🤣🤣
Black
modern physics needs a do-over. No progress in 70 years....
Man, I completely lost the plot halfway through this vid when they started talking about cosmic strings or whatever hahaha. Some supermassive strings flying about out there in the universe or something?
wait, wormholes aren't real? ;_;
god is wonderful
Time travel my as
Only speculations. Wishful thinking. Speculation is only useful when it leads to an experiment. The rest is wasting time.
It was once thought that the chemical composition of the stars was something that could never be empirically tested.
@@EugeneKhutoryansky it was once though that the succession of causes could be infinite, that matter is everything that there is, or that God was not the necessary first uncaused cause.
Nope, this is all wrong...
In what way?
Or just a hunch?
Have you been watching the Dialect cracks?
Time travel belief reveals a complete misunderstanding of what time is.
Time is not a place that you can travel to (past/future).
It is not a "dimension" as it is nothing like the 3 dimensions to which it is often added.
It is a concept to help us understand our universe
.
Concepts cannot be affected by gravity.
It is our measuring devices (clocks, etc.) which are affected by gravity.
i wanna know how you stopped travelling time, i been out here doing that literally all the time and tbh its gettin old
but i think its apparent that the reason adding time to the 3 dimensions would help is because while its not something like the spatial directions, its definitely not nothing like them either
@@SplendidKunoichi
zzzzzzzzzzzzzzzzzzzzz
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NEXT !!!!!!