What are the Strings in String Theory?

Why strings? What are they made of? How did physicists even come up with this bizarre idea? And what’s all this nonsense of extra dimensions?

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Hosted by Matt O'Dowd
Written by Matt O'Dowd
Graphics by Luke Maroldi
Assistant Editing and Sound Design by Mike Petrow

In physics we like to reduce down our description of the mechanics of reality to the simplest possible form. We expect the most fundamental machinery to have the fewest possible moving parts – or free parameters. This is why the standard model of particle physics is considered incomplete. Its equations predict many things with stunning accuracy, but they first require us to tune many mathematical knobs and dials. We need to use physical measurement to fix 19 free parameters like the masses of particles. And then there’s gravity, which doesn’t fit into the standard model at all. So surely there exists a deeper set of cogs and wheels – a theory that brings all observable phenomena into the same mechanical framework. That would be a theory of everything, and this is the great hope of string theory.

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سلطان الخليفي

[mexmexican]

I’m glad there are well produced physics videos on youtube like this that don’t resort to sensationalism like other channels

[pluspiping]

This is the first time I'm actually understanding (and retaining) wtf the "strings" are in String Theory. Excellent background and explanation! Thank you!

[Pejvaque]

You guys not only get much more in depth with these complex subjects than other places, but somehow still succeed in making it digestible!

[yuvalne]

Wow, I didn't expect to be featured in the video. And my name was even pronounced pretty much correctly!

[craigdodman]

The whole universe literally just be vibing

[matthewkagemann]

I just ate string cheese while watching this video, and it is increasing my mass, eliminating my stress, and causing internal waves.

[Michaelca]

But I don't want any more dimensions. It is already hard enough to find my keys.

[reyeslerma]

I'm going for my associates degree in astronomy at the moment and love watching your videos to stimulate my mind no matter where I'm at. (I'm going to work toward a PhD)

[Bluemilk]

*Me during the video*
"Yup... Uh huh... Makes sense... Of course... Jeez, this guy's actually explaining String Theory, and everything he says makes perfect sense"
"So what was the video about?"
"Pff"

[stephenbrand]

Man every time I try and really focus on this stuff I’m almost immediately confronted with words I have to look up and before I know it 5 minutes of the video have played without me having really understood or absorbed any of it in a meaningful way. Yet still I watch.

[vytautasdanielius]

Are the strings that control gravity called G-strings?

[MOSMASTERING]

I love this channel. There's no way these videos are boring.. they're about the universe and everything in it!

[hunterstephens]

"You guessed it."
"I did?"
"Strings."
"Oh."

[starcrashr]

Q: "What are strings made of?"
A: "It's strings all the way down!"

[ASLUHLUHC]

This is what happens when you leave theoretical physicists on their own for too long

[painterman]

can't believe anyone would say that any of your video's are boring?" ...no way! i learn something new every time i watch one of your video's .. to me every single video you make is incredibly interesting and mind expanding, and i want to thank you for all of your awesome video's Matt* ....

[vacuumdiagrams]

Historical detail at 6:50: It was De Broglie who thought of Bohr's model in terms of standing waves!

[phnon]

"Oh and we needed to add 22 dimensions to the familiar 4, no biggie!" xDD

[javierab]

I wish I could live enough to see if we finally get to an answer for this 😭

[raspas]

23andMe is involved in multiple scandals with selling the data of their customers. Selling without informing them of course. I would really think about changing the sponsor.