String Theory Explained - What is The True Nature of Reality? 

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Isn’t it crazy how we’re basically just a bunch of particles trying to understand themselves

"seeing is touching" *angry museum noises*

"If the universe is a play, the particles are the actors, the gravity is the stage." That was epic, quote of the century. Edit:3 more likes and 500! Thanks

I cannot express how much I liked the way you presented all of them into a single video! Sounds really simple and understandable

"The more you know, the less you know"

“I like your funny words, Magic man.”

In chemistry class, we learned about the history of the various models of the atom. They were all wrong to one extent or another, but they were still useful to think about, and I think worth learning about.

Its fascinating as to how such calculations are even carried out. And to think universe has so much depth which keeps on increasing the more it's explored. I really like how Kurzegesagt takes complex topics and simplifies it; the use of analogies may not be as accurate still make it even easier to understand. Thank you!

If string theory is proven one day someone will ask,” what are the strings made of.” Here we go again.

10,000 B.C.E: *Smashing rocks together* 2020: *Smashing subatomic particles together*

We are the particles that we are learning. We are learning ourselves

"if the universe is a play, particles are the actors, and gravity is the stage", well said👏

Is it me or does everybody come back every 6 months when they forget what string theory is

Aliens flying by: Oh look the humans finally started kindergarten

So good! I’m not an physic expert, I’m illustrator. But this explanation was so clear, and I barely know a little bit more about this difficult topic. Thanks.

Holy crap, you just explained one of the most complicated subjects out there in 8 minutes like it's nothing. Wow, major props.

I`ve never felt this stupid

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Gravity isnt actualy a force thats why it is different to other forces. The only reason we treat it as a force is because its observable effect is simmilar to one. I love your visualisations of such stuff so much, you managed to explain it beeing geometry crystal clear in seconds. Hats off

“Seeing is touching” Primary School Teachers: *I Would Like To Disagree*

You should have started with "It was a warm summer evening in ancient Greece..."

Damn, I‘ve learned about the Heisenberg uncertainty principle multiple times now, but I never quite understood why observing a particle affects its behaviour. This vid explained it perfectly!

This made my brain blow up. PLEASE MAKE MORE VIDEOS I LOVE THEM But seriously, I've been searching for a video like this to actually explain string theory to me (who studies biology and has nothing to do with physics :') ) in the easiest way ever Thank you so much it was incredible❤

“We thought we reached the end of reality, until we decided to smash them together really hard” -physics history

For those of you still confused, here is an elementary breakdown of String Theory and what was said in the video. It’s a little lengthy but I guarantee you’ll be able to understand it (Or at least I hope) Once upon a time we thought the smallest, most fundamental thing that makes up everything, was the atom. We now know that you can get smaller (and more fundamental if you will) than that. It turns out that the atom is made up of 3 particles: Proton, Neutron, and the electron. For awhile, we thought that was as small as you could go. But we now know that the Proton and Neutron are made up of smaller particles called Quarks (we’re pretty sure that the electron is fundamental and nothing makes up the Electron other than energy… So now we ask ourselves, what is more fundamental than a Quark? What is smaller? In other words, what makes a Quark? Is it another particle that’s even smaller? We don’t know. This is where String Theory comes in. String Theory suggests that it does get smaller. The tiniest, most fundamental building blocks of matter and the universe are tiny strings. Little filaments of energy that vibrate and dance around (as seen at 5:01). And every fundamental sub atomic particle in the universe was made by these vibrating strings. If a string vibrates this way, then an electron is made. If it vibrates another way, then a Quark is made. If it vibrates in another way, then a neutrino pops out… so on and so on It also turns out that the math behind String Theory tells us that our Universe has 10 dimensions instead of just the 4 that we know. 9 spatial dimensions and 1 temporal dimension (AKA time). When these strings vibrate, they aren’t just vibrating in our 3 dimensions (up/down, left/right, forward/backward). Instead they are vibrating in 9 different dimensions. I dare not try to explain this further SIDE NOTE: There seems to be confusion as to whether String Theory suggests that there are 10 or 11 dimensions. It depends on if you are talking about “classic” String Theory or a similar version of String Theory called “M-Theory” One of them typically states 10, the other 11. It also depends on the source you look at. Some sources use those two theories interchangeably. It’s all kinda confusing To also add one more thing that is very important…. The thing scientists are most interested about concerning String Theory is less of anything I mentioned above but instead something called “Quantum Gravity” Einstein’s Theory of General Relativity is extremely accurate and has been one of the most useful tools for understanding the universe around us. But it only answers problems for all the large scale things in the universe: Gravity, Black Holes, Time, Light etc… The other side of the coin is Quantum Mechanics. Which deals with all of the smallest things in the universe: Atoms, subatomic particles, a whole bunch of other behaviors and phenomena at very tiny scales, etc… Relativity and Quantum Mechanics are the two most accurate and all-encompassing branches of science known to Man. However, they don’t work together. Quantum Mechanics doesn’t work with large scale stuff and Relativity doesn’t work at Quantum levels. So you might think that one of them obviously has to be wrong then. But they aren’t. Again, there is no problem scientists have ever thrown at these two fields that doesn’t get solved, except when you try to marry the two together. Bringing the two together successfully is something called “Quantum Gravity”. If we can figure out Quantum Gravity, that will probably be the biggest discovery ever made in history. At least one of them. It would help us solve everything (loosely speaking). There is nothing more mouth-watering to scientists than Quantum Gravity. It just so happens that if String Theory is true and we can figure it out, it would solve for this Quantum Gravity problem. That’s mostly why String Theory is so enticing to scientists. More so than the other cool stuff I mentioned a bit earlier. It would win whoever figured it out a lifetime of Nobel Prizes! (I’m being a bit dramatic of course, but you get the idea! lol) Keep in mind, when ST was first proposed, scientists were watering at the mouth. But even to this day there is no real proof/evidence that these Strings exist. And because of that, ST is kinda becoming a joke. Day by day, ST is taken less seriously than before and a lot of physicists (like Brian Green) essentially get told to move on and forget it (roughly speaking). Other than some fancy mathematics, there hasn’t really been anything to show us that it is real EDIT: I keep adding on to this. Hopefully this is the last addition. String Theory is also known as “The Theory of Everything” for obvious reasons. Also, earlier I mentioned that Quarks are the smallest particles that we know of. But I kinda made it sound like there was only one type of Quark. Let me clarify and mention that there are 6 types of Quarks that exist in the universe: Up, Down, Top, Bottom, Strange, and Charm Quarks Protons are made out of two types: 2x Up Quarks and 1x Down Quark Neutrons are the opposite: 2x Down Quarks and 1x Up Quark EDIT AGAIN: Earlier I said that the electron is essentially just made up of energy. To clarify, more accurately speaking, it’s a negative electrical charge that exists as a cloud of probability in certain orbitals around the nucleus. Ya it’s kinda confusing. The Bohr model of the electron was that the electron was a point particle that orbited the nucleus in discreet orbital shells. This is the classical simplified model that we’ve all learned in school. Quantum mechanics gave us a more accurate understanding that tells us that model is inaccurate and it instead works the confusing way I explained a few sentences ago. The point is that no one has ever seen an electron and we are pretty sure nothing smaller makes up one EDIT AGAIN: There’s a few other juicy answers I gave down in the replies when someone asked me a follow up question… if you’re interested NOTE: If you need clarification on what I meant by…. “However, they don’t work together. Quantum Mechanics doesn’t work with large scale stuff and Relativity doesn’t work at Quantum levels…” Feel free to ask and I’ll be sure to elaborate!

Thank you for making such complicated stuff more understandable!

2:25 Jesse, we need to know when and where a particle is going with absolute precision.

I’m just impressed and excited that over 16 million people(views) wanted to learn about string theory. Whether you can comprehend it now or not, well done everyone 👏🏻

church: now, gravity, will you marry quantum physics? gravity: ughh no! scientists: be a lot cooler if you did

Thank you so much, I have been trying to understand this theory for so long. Your video perfectly explains it!

Wow, you just explained the Heisenberg Uncertainty Principle in a way that makes intuitive way, I never understood why we couldn’t know where electrons in an atom were without losing other characteristics.

I'd like to laud the animator, he/she did a great job here

This animation is eyecandy.

2:30 *_sarcasm intensifies_*

amazing how seamless the transitions in the video are!

I like how they can explain the latest theory of the universe faster than a RU-vid video about the plot of Evangelion

This really makes me appreciate how smart some people are. Or that so many people contributed smaller ideas that lead to these crazy hypotheses.

breaking bad was so popular they named a quantum mechanic principle after heisenberg

thank you i finally understand the "why" of the whole 'collapsing of the wave function when the particle is observed' thing

“It’s so important it has its own name” Me, who also has a name: :)

NEVER change the narrator for your videos! :)

I am not a physics student but this....wow. Just wow. a Marvellous presentation and understanding of string theory. to be honest, the tbbt show got me interested in this. 💙😊

I’d like to say, thank you I’m only on 8th grade and I’m trying to get ahead a bit in science and this helps a lot!

A summary of me watching Kurzgesagt : I really want to be smart, but, really, it's difficult.

Im not even listening to what hes saying at this point im just looking at the ducks living their daily lives

This brought up memories 12 year old me searching up string theory videos so I could seem really smart to my friends

2:14 I had heard about quantum stuff changing when you look at it, but it didn’t make sense until now, thank you so much for explaining it so easily :))))

Kurzgesagt: "seeing is touching". Me : profusely pouring sanitizer into my eyes.

5th grade physics teacher: Atoms are the smallest thing in the universe. Me knowing about quarks: I'm about to end this guy's whole career.

Nice animation and storytelling! String theory has another name: dodecahedron rescue oblongated paths. Take cohesive shapes that have higher dimension than their neighbors, then “rescue”, or convene, then with all other matter. The resulting shapes are fields and describe specific motions, using now-consistent “particles”. Publishing! I enjoyed the film.

I love the original Zelda reference. I really appreciate what this channel does to help educate a regular carpenter like myself on complex issues I normally wouldn’t be able to grasp.

This mans voice is so calming it’s crazy. He could literally tell me any story and I’d be amazed

2:49 “we did what humans do” *shows duck writing

These videos are pretty much exactly what i would expect the The Guide to sound like

Very impressed with this video. I have always been interested in astronomy and physics. It was things like this that drove me to enter those professions. Thank you for feeding my insatiable curiosity about the universe and the wonders that we discove

Exciting times we live in! I never thought I would see the day humanity would successfully detect gravitational waves, and here we are! Praise be science! 🙏🔭

The more our circle of knowledge expands, the bigger the circumference of ignorance surrounding it gets.

All of your videos are beyond awesome🙌 thank your entire team for making difficult concepts understandable and science interesting

2:15 that's the observer effect, not the Heisenberg uncertainty principle. The uncertainty principle is a fundamental limit to how accurately we can know the physical properties of a particle, unrelated to the instruments used.

The universe are things. I called this the things theory.

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New discoveries, observations, and theories can make such a difference. The symmetron theory for instance may imply these other dimensions exist (along with dark matter/energy) and we simply lack the means or scale to interact with them. like there could be a dimensions groupings with a few overlapping. Things always get more complex with more parts the longer we look.

"Kurzjesjgagshakngt" never fails to deliver good content.

I like playing with String Theory. Signed, Schrodingers Cat

Universe: "That's not how things work" Humans: *But what if it do be like that*

I feel like I've watched this like 10 times this year, but I keep dissociating like midway through the video lol

2:25 is the moment science became heisenberg

this video called me stupid a few hundred times lmao

Gravity: I’m about to end this whole man‘s career

5:42 VERY lovely showcase of existential birds for each dimension 😍

Wonderful video with wonderful graphics and humor , thanks for posting and simplifying a complicated but fascinating matter...

For anyone who wishes to go further, I would advise Brian Greene's book "The elegant universe", a beautiful account about string theory!

What if when you died, you wake up in an alien body holding a bong and a nearby figure asks you "How was it?"

ive watched so many Kurzgesagt videos today, like over 20 of them, I cant stopppp. Steves voice is just too nice to listen to

4:50 me when i accidentally draw a perfect circle

90% of the comments here: "i am something of a scientist myself"

*The earth is a string*

2 AM in the morning and I enjoy watching documentaries about string theory. I’m awesome

The bird doesn't like to be poked sir.

When he said "2 plus 2 is 4," I instinctively said "quick maffs" and now I'm disappointed in myself

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gotta love the squishy disturbing sound effect at 1:31 when the photons penetrate the eye like an arrow 😂

In a Nutshell back at again with an epic video, putting the rest of us content creators to shame with their immaculate and pristine quality videos.

"A line; or a string!" *Draws a circle*

Rewatching this and only now noticed the fleshly sound playing when the photon hits the eyeball. Whoever put that in, you've successfully made me wince 😭

the stylized animation in these vids is superb!

Now imagine after 50 years the solution came out to be "Knot".

"What we know is a drop. What we don't know is an ocean".

when you describe things this muchhh goood, it helps people like me to imagine the problem and come up with a solution ! ( maybe someone could solve the problem , at least in his/her imagination untill he/she becomes a scientist :) ) .

Point theory: What's more complicated than a point? A String! String theory: What's more complicated than a string? A Circle! Circle theory: What's more complicated than a circle? A Triangle! Triangle Theory: What's more complicated than a triangle? A Square! So on and so on, until the shape becomes a circle again.. and what is a circle when zoomed out? A point....

Still waiting for that day we will finally come to a conclusion and everything suddenly makes sense

What were your grades the whole year? Me: 3:31

beautiful, haunting background music. nice pick

I can always count on Kurzgesagt to get me hyped about physics.

"Seeing is touching" Me with glasses: I think my touch is off

The one dimensional bird is so funny lmao Fabulous animation, Hat's off Kurzgesagt!!

I have studied chemistry at the university, it would be worthy if I would have seen it before, great video!

I just wanna say a big thank you to the sound and music designer(s). You guys are really doing such a great job.

*Loved* the music in this one!