What is String Theory?

There is a great conflict in modern physics: the incompatibility between general relativity and quantum mechanics. This has caused much confusion in the scientific community, and finding a solution to this conflict would be the biggest breakthrough in science of this generation. There is one theory that seems promising in this search for a veritable “theory of everything.” That is string theory.

Script:

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Look. Above us there are billions upon billions of planets, stars, and galaxies - many of which are several times the size of Earth. Because of the enormous scale of the cosmos we need to make some adjustments to our understanding of physics.

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Inside just one grain of sand, there is an unthinkable number of atoms - beyond billions and trillions. Even crazier is that atoms still can be broken down into smaller particles. This is the quantum realm, and to understand the universe at such a small scale, we must again adjust our view of the world around us.

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When analyzing the world on stellar scales, the most important thing to consider is gravity. While the great scientist, Isaac Newton, helped us to measure the effects of gravity to great precision in the 1600s, we weren’t able to truly explain it. That is, until Albert Einstein came along. Einstein was able to finally explain gravity by illustrating the universe as a fabric of both space and time. And just like any other fabric, it can be distorted. Einstein predicted that massive objects warp the fabric of spacetime, causing less massive objects to “fall” towards it [demonstration with fabric and balls]. This theory accurately explained the attractive force of gravity. Finally, we had a theory that explained both why things fall to the ground and why the planets orbit the sun.

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When we look at the small things of our universe - things like electrons and quarks - they start acting really weird. Measurements that are defined on normal scales, like position and velocity, become uncertain at quantum levels - particles are actually too small to measure. In fact, the only way to take accurate measurements in the quantum realm is to assume that the universe is split up into many different sections, or quanta, like a sicilian pizza.

It seems odd to some, but years of quantum mechanical research proves that this leads to correct calculations, meaning that, at a fundamental level, the universe consists of many, many tiny pieces.
If you look closely at these two theories, you will notice something is off.

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General relativity requires that the universe is smooth and continuous.

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Quantum mechanics requires that the universe be disjointed and discontinuous.

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These two theories are both experimentally accurate, but have two very different views of the universe, making them incompatible. This has been the dilemma of modern physics for several decades now.

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However, there are advancements being made in physics suggesting that these theories are not really incompatible, we are just missing something. That something, it seems like, is string theory.

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String theory says something quite simple: fundamental particles - such as electrons and quarks - are not point particles like we always imagined. Actually, they are little strings. This sounds too simple to fix the problem, but it says something incredibly profound. Strings, unlike points, can move and vibrate within themselves. These vibrations can explain the different properties of all the quantum particles. Perhaps all these particles are actually made of the same type of string, but only have different masses, sizes, or energies, just because their string is vibrating at a different frequency.

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As interesting as that is, there is something even more profound in this statement: these strings can act as their own quanta. The reason quantum mechanics is quantum is because it assumes the universe itself must be divided - this is the only way we get the right answers. String theory states that the universe does not have to be like this; instead the string creates its own limits and leads to the same correct calculations. In string theory, both general relativity and quantum mechanics can work.

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String theory has the potential to unify the two great theories of modern physics. String theory, if proven correct, would be the theory of everything.

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Of course, since string theory is so young, more research must be done before it can be proven true. This could take many years, or even decades, but the results we have now look promising.

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Does String Theory change your view of the world? Let us know in the comments below!

Sources

The Elegant Universe by Brian Greene
Theory of General Relativity by Albert Einstein

Cast & Crew

Director & Producer: Jaimee
Cam: Nancy
Editor: Yvonne
Sound: Shariar
Talents: Yvonne // Jaimee

[akshhay]

very nice and outstading appreciate the hardwork :)))

[vanessanowakowska]

and you can't have nodes more then 4 dimensions unless you count them as sheets.

[segarpustarsus]

Quantum Mechanics and General Relativity is like Earth is Sphere and Earth is Flat.

[damanybrown]

If density is mass per unit of volume and black holes have different masses how can black holes then have infinite density unless its volume is 0 (I cannot conceptualize 0 volume for anything that takes up space, which I assume a black hole does)? Second is the density of a white hole negative infinity? Lastly how is an extreme such as infinite density measured with the value being infinite or is this assumed because light cannot supposedly escape/leave a black hole?

[MegaBeata]

Salve giorni fa mi sono scontrata qua su you tube con un uomo che dice che la razza umana non si estinguera' mai in quanto ci sarebbero (secondo la teoria delle stringhe) degli universi che non avranno mai una fine ( a differenza del nostro universo che invece lo ha secondo gli astrofisici, perché morirà sia il sole che l universo in cui adesso viviamo tra miliardi di anni) volevo sapere se effettivamente è vero che esistono questi universi che non hanno una fine e che l essere umano potrà vivere in futuro in questi universi sopravvivendo? Questi universi infiniti avranno poi le condizioni per la vita come c'è l' abbiamo in questo attuale?

[taylorwells]

This might seem like a dumb question I dont know much about physics but when you break everything down into the smallest pieces of reality, these strings in the case. Are they made up of anything? And how or why do they vibrate at different frequencies. How does anything do anything is what Im basically asking lol

[joannakesler]

I made a sincere effort to watch and learn from this video, but the piano/background music was SO LOUD, that I was distracted and missed a good bit of the info. Physics is difficult off the piano!

[physicsandmathamatics]

so what is that thing wich is missing and how string theory is joining both quantum mechanics and classical mechanics ????👍🤔😐🤔

[iknowitall]

Tossing the characters all over the screen makes it look so corny