# Quantum Computers Explained - Limits of Human Technology

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**Published on Dec 8, 2015**- Where are the limits of human technology? And can we somehow avoid them? This is where quantum computers become very interesting.

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Quantum Computers Explained - Limits of Human Technology

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USS Voyager21 hour agoWo finde ich die Deutsche Version?

Overproud Indonesian ProductionDay agoBut,can it run S.T.A.L.K.E.R.?

NATmusicDay agoAll of this is very very interesting but I'm feeling like I'm getting lost behind... from where should I start studying to understand something more of this? Physics? Math? All?

Ryan_cool_gamerDay agoMy brain just exploded

utoobwa2 days agoIs there something in English available?

Gopal Smart2 days agoScience never fails, and lies. Our brain and mind needs high tech in every field. AUSTRALIAN ACADEMY OF SCIENCE GIVE LOT OF SCIENCE INFORMATION. I WELCOME MORE VIDEOS PL. GOPAL ARTIST. SOUTH INDIA, PIN 641014

Nizzloid2 days agoCan it run tetris on 60 fps

Druvis Eglite2 days ago4:44 Dial the Stargate.

Israel Vidana3 days agoI want a quantum smartphone

Emperor Galaxian3 days ago2018 and I have a *HUGE* question about Quantum Computers:

Can it Run DOOM?

Samuel Carvajal3 days ago0:08 its the duck from DHMIS

intanwulans3 days agoLimit of the technology?

MJ Ozog3 days agoError 404: person.exe was not found

Denny 2004 days agoMan, was soll das? Videos mit deutschen Titeln sind auf englisch und Videos mit englischen Titeln sind auf deutsch. Nicht dass ich's nicht genau so gut verstehen würde, aber das ist halt nervig.

BaneDonegan BadDay4 days agocan it run crysis tho

Eduardo Sanchez4 days agoOk, so quantum computers have weird bits...

But I can use a virtual machine on my PC and click on that "Free Taco Bell Samples!" link

Old Bird4 days ago^{+1}Lol so that's why theydont really exist yet! They're not really reliable!

Saphire Ninja5 days agoNerd.exe has stopped working

Saphire Ninja5 days agoBut can it run Crisis?

The TinyTardis5 days agoCould you please do a video on quantum tunneling and/or a video on quantum mechanics?

I understand that there very complicated so i understand why you wouldn't

Jezrel Carvellida5 days agoHow Familiar are you with the Gears Wars?

Is this a Rick and Morty reference? :D

Rajinder Singh5 days ago^{+1}I haven't learned a thing!! (For some of you.. this is a Rick and Morty reference)

darklinkx85 days agoTIL seven year olds are the smartest beings in the universe.

E C6 days agoSimple glass of water will hold enough data for an entire World Super Computer. The study of written and spoken crystalluzation of data stored water is almost a reality. The mechanism of time bent and behavior of sub-atomic particles in quantum will be the paradigm shift in computing technology.

Joann Dillon6 days agoThis does not compute!

lRaziel16 days agohow many 7 years old do we need to run Crysis at 720p in mid settings?

Nguyễn Nam6 days agoSimpler idea of Quantum Bit: Spinning coin. Current state of this coin is both Head and Tail. When you want to "see", stop it by your finger and it will present 1 side. The other side is reverse without looking.

Harry Baguio7 days agoYou lost me

Blue Zerg7 days ago^{+1}*whats is the default search engine?*

Crash7 days agoBut can it run crysis?

TemBark7 days ago^{+1}providing more hacking tools to csgo noob

Shadow779998 days agoI think its safe to say were all not smart enough to understand this arent we?..

Justin Hannay8 days agoThis is wrong. 14nm isn't the size of the transistor, it's the space between them.

Nch N ff8 days agoMy brain is too stupid for this...shame on me

SYED AZEEM8 days agoI am the students of Btech from electrical and electronics engineering streem

And i easily understand all the concepts Quantum physics and Analog and Digital electronics which are come across your brilliant video ..😇😇😇

Believe me a person who doesn't have any knowledge about such subject can't understand at all..

This video also give s me hidden msg that their is 🤗🤗much need of well advance engineer's for Advanced Humman Civilization ..

Thanx for this video its help me alot in gathering my knowledge of different subjects at one ..place 😍😇😇

Fernando Vito8 days agoand there is only one way to find out

3 sextilion years later

ded

Barry Potter8 days ago^{+2}*Brain intensifies*

got any 3's?8 days agoDoes anyone else hear the music from "PewDiePies Tuber simulator" in the background.

Max Blarb9 days agoBut can it run fortnite?

The IRIS9 days agothis channel is so much easier to understand

Shadow10 days agoin 30y this will be a home computer

hgb 010 days ago^{+1}Can we put qubit in normal Computer

Xwater10 days agowhy you put to finnish are you finnish , ihmisen teknologian rajoitukset

Muhammad Al Fatih10 days agoCan it divide by zero?

Cylux Halfheart10 days agoWhat?

Psycho Andreas10 days agoNow they say the wont replace normal pc's...

This reminds me of something 🤔

Psycho Andreas10 days ago0 Ping with superpositions 😱

Kablash9 days agoWith quantum entanglement you mean? Unfortunately not, quantum entanglement can't be used to send information. It would be the dream though..

FinnieBallzzz10 days agomy brain hurts

YellowDasher5 days agoBut how can something that doesn't exist hurt?

Zninja Playz11 days agoKirzgesagt spent only 7:17 minutes to tell us about quantum computers but it took me 7:17 hours to understand it..

10000 subscribers without Videos12 days agoWindows 20 right there

Cade Prime12 days agomy head hurts

Bray Munroe12 days agoDamn so once we can make quantum computers are entire current password system will be completely undone

raditya respati12 days agoI thought y'all guys felt smart enought after watchin rick n mortay.

ToSixZer12 days agoNo joke my brain hurts

Juan Lema-Sinchi13 days agoDid I hear a pack a punched weapon when the photon hit the filter?

Keisuke Takahashi13 days agoAwesome video, you motivated me. Now I’m off to build a computer!

Alin Gupta13 days ago^{+3}1:44 basic math huh, 0*1 isn’t 1. It’s 0.

Knightlycat moonSpotter7 days ago^{+1}That's the only wrong thing you spotted at 1:44?

lol it was supposed to be a joke xd

Aiseruchan13 days ago4:29 me rn

Saheb 00014 days agoComputer is best .it will best always

Meme Mistake14 days agoI want a Quantum Gaming PC bitch.

Wasd7814 days agoEvery science video I come across like this one I can't concentrate but only think WHERE ARE THE DAMN SPACESHIPS AND SPACE COLONIES

I WANNA GO TO SPACE.

Zachary Zoet14 days agoI finally understand that observation or measurement of an photon in superposition requires the photon to stop 🛑 wiggling, zooming and spinning, like predicting the result of a coin toss where one cannot actually know which side’s up until it lands. Thanks

Student Of The GAME15 days agoIt sounds like they're trying to make them based on the same tech we make regular computers with.. Why? The result of a superpositioned particle doesn't depend on the input - it depends on the observation. The damn thing runs reverse.

Dark Coffee Bean15 days ago2:29 who caught that Rick and Morty reference?

DamianZocker15 days ago^{+1}But can it run Crysis?!?! Thats the question of life with quantom computer

Crtipz Gaming15 days agohow about just not make the computer smaller just make it bigger geez

Matthew Bay16 days ago"the more you buy quantum GPU the more you save" Nvidia in 2030

Kablash9 days agoOnly 100.000$ for the QTX 1080.

Lucrezia16 days agoWhy do I find it so difficult to understand?!? 😭😭😭

SVINKA _GD16 days agoMindfuck

Optic G17 days agoSo a subatomic gtx 1080?

Dia 7 é 1717 days agoQuantum Computers, Dark Energy, 4th dimension, Black Holes it doesn't make any sense. Scientific calculations that lead to absurd theories and nowhere.

0 Subscribers13 days ago^{+1}Dia 7 é 17 You do realize that there are already working prototypes of quantum computers? Also your understanding of math and physics seems to be 0 since you call them absurd.

Alp Fidan17 days agoThat rick and morty ref. tho

Discovaria18 days agogamers are happy to get gaming quantum computer

burak kapıcı18 days agoMy brain is burning...

Berlin9999919 days agoWow, you used the IBM Atom Boy at 1:55. I really like that :)

windigoking19 days agoCan i install lime wire on the quantum computer?

Jargo Neo19 days agoCan it run this “(*-*)”

atomic93620 days ago^{+1}''wow your ex really hates you''

Thanks compuer

Think before you act.21 day agoGhad bless you!

GoldenBeans22 days agoso i have multiple passwords wich are hard to decypher , and you're telling me if they succesfully make a quantum computer, and it gets it the wrong hands it doesnt matter whether you have a password?

thanks, good to know to be flipping paranoid now

GoldenBeans21 day agogood, encryptions are fun :0

Ambient Morality22 days ago^{+1}only some encryption methods are insecure with quantum computers. All of them are still hard to break - they would require a far larger and far more stable quantum computer than anything we have today. We know new encryption methods which are slightly slower (by an order of magnitude or two, but still computers are fast) but are quantum-resistant.

Buhe Billion22 days agoeven if COD wont run;it would be great

tom fazz23 days agoBro what the fuck am i watching? Im so confused 😂 (not digging the vid)

Jaqueline Rios23 days agoBut can it minecraft?

gym is life24 days ago^{+2}I dont Need school

Stp_poika !8 days agoShadow77999 I live under a bridge I dont Need that crap

Shadow779998 days ago^{+1}But you need dat sweet diploma ( ͡° ͜ʖ ͡°)

verdy mrajasa24 days agoDont you dare create real ultron system

ItzYoBoi DatOneGuy24 days agoWut

TheUnknownElite Gaming And More24 days agoDoes it mean it is possible to make robot that targets viruses and could split Hiv From Dna

Emine Yaman24 days agoBut, can it broking in my heart?

Greebeth7424 days agoGOD I love your channel. You teach people stuff that's important, but not well known, and with birds no less.

Hang Jebat24 days ago^{+1}Scorpion anyone?

Ivo k25 days agoBut can it run minesweeper?

BaskingBlade25 days agoThe Bloch sphere is a representation of a qubit, the fundamental building block of quantum computers.

Part of a series of articles about

Quantum mechanics

{\displaystyle i\hbar {\frac {\partial }{\partial t}}|\psi (t)\rangle ={\hat {H}}|\psi (t)\rangle } {\displaystyle i\hbar {\frac {\partial }{\partial t}}|\psi (t)\rangle ={\hat {H}}|\psi (t)\rangle }

Schrödinger equation

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Quantum computing is computing using quantum-mechanical phenomena, such as superposition and entanglement.[1] A quantum computer is a device that performs quantum computing. Such a computer is different from binary digital electronic computers based on transistors. Whereas common digital computing requires that the data be encoded into binary digits (bits), each of which is always in one of two definite states (0 or 1), quantum computation uses quantum bits or qubits, which can be in superpositions of states. A quantum Turing machine is a theoretical model of such a computer, and is also known as the universal quantum computer. The field of quantum computing was initiated by the work of Paul Benioff[2] and Yuri Manin in 1980,[3] Richard Feynman in 1982,[4] and David Deutsch in 1985.[5]

As of 2018, the development of actual quantum computers is still in its infancy, but experiments have been carried out in which quantum computational operations were executed on a very small number of quantum bits.[6] Both practical and theoretical research continues, and many national governments and military agencies are funding quantum computing research in additional effort to develop quantum computers for civilian, business, trade, environmental and national security purposes, such as cryptanalysis.[7] A small 20-qubit quantum computer exists and is available for experiments via the IBM quantum experience project. D-Wave Systems has been developing their own version of a quantum computer that uses annealing.[8]

Large-scale quantum computers would theoretically be able to solve certain problems much more quickly than any classical computers that use even the best currently known algorithms, like integer factorization using Shor's algorithm (which is a quantum algorithm) and the simulation of quantum many-body systems. There exist quantum algorithms, such as Simon's algorithm, that run faster than any possible probabilistic classical algorithm.[9] A classical computer could in principle (with exponential resources) simulate a quantum algorithm, as quantum computation does not violate the Church-Turing thesis.[10]:202 On the other hand, quantum computers may be able to efficiently solve problems which are not practically feasible on classical computers.

A classical computer has a memory made up of bits, where each bit is represented by either a one or a zero. A quantum computer, on the other hand, maintains a sequence of qubits, which can represent a one, a zero, or any quantum superposition of those two qubit states;[10]:13-16 a pair of qubits can be in any quantum superposition of 4 states,[10]:16 and three qubits in any superposition of 8 states. In general, a quantum computer with {\displaystyle n} n qubits can be in an arbitrary superposition of up to {\displaystyle 2^{n}} 2^{n} different states simultaneously[10]:17. (This compares to a normal computer that can only be in one of these {\displaystyle 2^{n}} 2^{n} states at any one time).

A quantum computer operates on its qubits using quantum gates and measurement (which also alters the observed state). An algorithm is composed of a fixed sequence of quantum logic gates and a problem is encoded by setting the initial values of the qubits, similar to how a classical computer works. The calculation usually ends with a measurement, collapsing the system of qubits into one of the {\displaystyle 2^{n}} 2^{n} eigenstates, where each qubit is zero or one, decomposing into a classical state. The outcome can therefore be at most {\displaystyle n} n classical bits of information (or, if the algorithm did not end with a measurement, the result is an unobserved quantum state).

Quantum algorithms are often probabilistic, in that they provide the correct solution only with a certain known probability.[11] Note that the term non-deterministic computing must not be used in that case to mean probabilistic (computing), because the term non-deterministic has a different meaning in computer science.

An example of an implementation of qubits of a quantum computer could start with the use of particles with two spin states: "down" and "up" (typically written {\displaystyle |{\downarrow }\rangle } |{\downarrow }\rangle and {\displaystyle |{\uparrow }\rangle } |{\uparrow }\rangle , or {\displaystyle |0{\rangle }} |0{\rangle } and {\displaystyle |1{\rangle }} |1{\rangle }). This is true because any such system can be mapped onto an effective spin-1/2 system.

A quantum computer with a given number of qubits is fundamentally different from a classical computer composed of the same number of classical bits. For example, representing the state of an n-qubit system on a classical computer requires the storage of 2n complex coefficients, while to characterize the state of a classical n-bit system it is sufficient to provide the values of the n bits, that is, only n numbers. Although this fact may seem to indicate that qubits can hold exponentially more information than their classical counterparts, care must be taken not to overlook the fact that the qubits are only in a probabilistic superposition of all of their states. This means that when the final state of the qubits is measured, they will only be found in one of the possible configurations they were in before the measurement. It is generally incorrect to think of a system of qubits as being in one particular state before the measurement, since the fact that they were in a superposition of states before the measurement was made directly affects the possible outcomes of the computation.

Qubits are made up of controlled particles and the means of control (e.g. devices that trap particles and switch them from one state to another).[12]

To better understand this point, consider a classical computer that operates on a three-bit register. If the exact state of the register at a given time is not known, it can be described as a probability distribution over the {\displaystyle 2^{3}=8} 2^{3}=8 different three-bit strings 000, 001, 010, 011, 100, 101, 110, and 111. If there is no uncertainty over its state, then it is in exactly one of these states with probability 1. However, if it is a probabilistic computer, then there is a possibility of it being in any one of a number of different states.

The state of a three-qubit quantum computer is similarly described by an eight-dimensional vector {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} (or a one dimensional vector with each vector node holding the amplitude and the state as the bit string of qubits). Here, however, the coefficients {\displaystyle a_{i}} a_{i} are complex numbers, and it is the sum of the squares of the coefficients' absolute values, {\displaystyle \sum _{i}|a_{i}|^{2}} {\displaystyle \sum _{i}|a_{i}|^{2}}, that must equal 1. For each {\displaystyle i} i, the absolute value squared {\displaystyle \left|a_{i}\right|^{2}} {\displaystyle \left|a_{i}\right|^{2}} gives the probability of the system being found in the {\displaystyle i} i-th state after a measurement. However, because a complex number encodes not just a magnitude but also a direction in the complex plane, the phase difference between any two coefficients (states) represents a meaningful parameter. This is a fundamental difference between quantum computing and probabilistic classical computing.[13]

If you measure the three qubits, you will observe a three-bit string. The probability of measuring a given string is the squared magnitude of that string's coefficient (i.e., the probability of measuring 000 = {\displaystyle |a_{0}|^{2}} {\displaystyle |a_{0}|^{2}}, the probability of measuring 001 = {\displaystyle |a_{1}|^{2}} {\displaystyle |a_{1}|^{2}}, etc.). Thus, measuring a quantum state described by complex coefficients {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} gives the classical probability distribution {\displaystyle (|a_{0}|^{2},|a_{1}|^{2},|a_{2}|^{2},|a_{3}|^{2},|a_{4}|^{2},|a_{5}|^{2},|a_{6}|^{2},|a_{7}|^{2})} {\displaystyle (|a_{0}|^{2},|a_{1}|^{2},|a_{2}|^{2},|a_{3}|^{2},|a_{4}|^{2},|a_{5}|^{2},|a_{6}|^{2},|a_{7}|^{2})} and we say that the quantum state "collapses" to a classical state as a result of making the measurement.

An eight-dimensional vector can be specified in many different ways depending on what basis is chosen for the space. The basis of bit strings (e.g., 000, 001, …, 111) is known as the computational basis. Other possible bases are unit-length, orthogonal vectors and the eigenvectors of the Pauli-x operator. Ket notation is often used to make the choice of basis explicit. For example, the state {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} {\displaystyle (a_{0},a_{1},a_{2},a_{3},a_{4},a_{5},a_{6},a_{7})} in the computational basis can be written as:

{\displaystyle a_{0}\,|000\rangle +a_{1}\,|001\rangle +a_{2}\,|010\rangle +a_{3}\,|011\rangle +a_{4}\,|100\rangle +a_{5}\,|101\rangle +a_{6}\,|110\rangle +a_{7}\,|111\rangle } {\displaystyle a_{0}\,|000\rangle +a_{1}\,|001\rangle +a_{2}\,|010\rangle +a_{3}\,|011\rangle +a_{4}\,|100\rangle +a_{5}\,|101\rangle +a_{6}\,|110\rangle +a_{7}\,|111\rangle }

where, e.g., {\displaystyle |010\rangle =\left(0,0,1,0,0,0,0,0\right)} {\displaystyle |010\rangle =\left(0,0,1,0,0,0,0,0\right)}

Beytullah Dereli25 days agoOur brain works similar with that way imo. When we dream instantly it appears when we decide to what we wanna look.

Ambient Morality22 days agoYou don't know anything about how a quantum computer works, so you can't make connections like that.

Quantum computers have nothing to do with doing "everything at once", whatever that means.

Phone Naing Kha25 days agoPermanent brain damage

Rob25 days agoFull credit for the Rick and Morty reference at 2:29.

Big thumbs up

Seth Hall26 days agonull

David Qebadze26 days agoooooh i get it now! everything is clear!

Jeffrey over900026 days agoBut can it answer Baldi's 3rd question in the second notebook in Baldi's Basics?

AMV-Senpai26 days agoif ""entanglement is a connection that makes each of the qubits react to a change in the other's state instantaneseouly no matter how far they are apart "" then it's faster than the light speed

Mojos Bigstick26 days agoIt's quantum baby.