How Does a Quantum Computer Calculate? The Simplest Explanation!

How Does a Quantum Computer Calculate? The Simplest Explanation! Terra Physica 44.7K subscribers Join Subscribe 1K Share Ask Save 51,362 views Dec 4, 2025 In this video, we will try, literally “on our fingers,” using the simplest words and analogies, to explain the basic principles of how quantum computers work, how these principles differ from the way classical computers operate, and why quantum computers should be able to do things that classical ones can hardly manage. Subscribe to my Telegram channel: https://t.me/physiovisio Support the project on Boosty: https://boosty.to/physiovisio Patreon: / yuritkachev Terra Physica simplifies quantum computing. Using classical physics analogies, the video explores how quantum computers leverage superposition for faster calculations. Discover how this contrasts with traditional computing methods. Summary How this was made Auto-dubbed Audio tracks for some languages were automatically generated. Learn more Transcript Follow along using the transcript. Show transcript Terra Physica 44.7K subscribers Videos About 87 Comments rongmaw lin Add a comment... @davewilliams9569 6 days ago I understand the basic principles behind quantum computing, but from an engineering perspective, I have not seen any video that explains the mechanistic process of the hardware. We see all the tubing and wires, but no explanation of what it is. I would really like to see that, and I think it would help with the theoretical concepts. For example, in a traditional computer, you have a physical CPU, power supply, data storage device, keyboard, memory storage, cooling fans, etc. Please show us the components of a quantum computer and how the components work together, 13 Reply 2 replies @Eugene-o6w 10 days ago Thank you. I am still confused but at a much higher level. 12 Reply @davidwright8432 11 days ago Please make equally clear videos about quantum computation, and quantum information. 4 Reply @josesaldivar655 12 days ago What I want to see in all videos, is an abstract at front with results. Then one decides to watch it full with details. I don't want to waste one hour to see results . 3 Reply @jeffreyluciana8711 12 days ago I'm building a quantum computer. As practice, I am standing 20 paces from a brick wall, running at full speed and smashing my head off the brick wall 6 Reply 1 reply @bobchiggs 4 days ago Best explanation I've heard so far. Reply @eugenefaber7638 10 days ago The background music becomes noise and is annoying when trying to understand what you are saying. I had to cut the video short for that reason. 2 Reply @kempinthewoods 13 days ago That was good. YES PLEASE DO make videos about computing with entanglement and interference! 1 Reply @patricksimone8845 13 hours ago I would love to see an example of a very simple calculation using quantum physics. I is still beyond my grasp to see how having various levels of probability actually supplies an answer. Reply @schmitzbeats6102 13 days ago How can a quantum gate be possible? Doesn't the input state need to be measured, and hence collapse the superposition? 3 Reply @grahamsalmons2027 1 day ago This was a very good explanation. I am intrigued as to how the technology is constructed: I see pictures of quantum computers but unlike a conventional device have no concept of what part is what or doing what. So I would love an explanation of that. Less cerebral than the actual subject itself I’m sure! Reply @judithtumwinemuwesa7543 3 days ago Very impressive. Reply @josesaldivar655 12 days ago The way to learn is to do a real exercise at least. 3 Reply @MolinaUdofo 2 weeks ago Wow! So, how DOES a quantum computer work? 5 Reply 1 reply @starshipproto 2 weeks ago (edited) Trick question - it doesn't. Every answer to everything possible exists in the substrate at the planck scale - the Universe's own Wavefunction. It just needs to stay focused for the short period it takes to perform the search. When it finds it the weight of the entanglements it forges to provide the result hits a threshold. The entanglements it makes to focus on the desired result gradually generates more and more informational gravity until that aforementioned threshold is reached triggering collapse and thus if it was able to hold that state long enough it delivers a correct result. 3 Reply @nickdsp8089 12 days ago So a classic computer makes the calculation stores the answer in a SINGLE memory cell and if not the correct answer it repeats the procedure until it finds one and this may take time (maybe years). The Quantum computer on the other hand finds all the results at once and then chooses the correct answer. There is a hidden problem here which is not mentioned. You need to STORE somewhere all the millions or billions answers before collapsing them to the correct one in a fraction of time. 3 Reply @mikefinnerty1852 12 days ago Fantastic! Reply @mikejurney9102 12 days ago So now we need to know exactly how the quantum computer manipulates the input superposition of states to get the output superposition of states where the most probable state is the correct answer. How are quantum gates constructed, and which ones are used for what purpose. Thanks. 1 Reply @ernestolombardo5811 3 days ago Excellent video, as always. But I feel compelled to make one strong suggestion: could you lower the volume of the musical track? At times during the course of this video, the soundtrack crosses the line from being in the background to being in the foreground, to the point of becoming a distraction from the real reason we're here: the knowledge being imparted. Following the words becomes more of an effort. I would even suggest lowering the music's volume by as much as 30%-40%. Reply @RogerKnight5 13 days ago These quantum people don't ever show 1. a problem that needs solving, 2 the code that programs the computer, 3 the output - It's all bollocks. Never see them demonstrate ONE SINGLE SOLUTION to a PROBLEM. 11 Reply 1 reply @Spookytooth1 6 days ago I would love to understand how the correct solution is extracted from all the superposed incorrect solutions after the single pass operation on them all Reply @jesusisunstoppable4438 2 weeks ago Soooo what is the Actual Qbit ? A photon ? An Electron ? Something else ? 4 Reply 2 replies @dbaytug 5 days ago QC is an example of how the question is coded is more important than the answer. But I do believe this is closer to biological sentience because neurones mimic superposition Reply @danielm3967 10 days ago Wow so i am pretty stupid is all i got from this video 😂 1 Reply @David-c5l5i 12 days ago A phd is required but I appreciate your efforts Reply @edwardstrassberger2024 10 days ago Please show how to decode Enigma messages and to play chess. Reply @BirkGed 10 days ago I thought this was pretty well explained. It stopped a little short of a question that I have, though it wondered into the neighborhood. I understand that the algorithm's output (where it discards the "incorrect" values and selects the answer) is probablistic, so that several iterations have to be run to "certify" the answer. What I DONT understand is that "in practice", that output, which is supposed to be narrowed or confirmed by iteration, on real machines often only takes one or a very limited number of trial outputs, even when the "phase space" of the answer is incredibly large. Who ordered that, and how does that happen? Reply @bicivelo 11 days ago Great explanation but how does a quantum computer handle the matrix even screen Saver??😮😅 Reply @jasam4374 12 days ago What kind of integrated circuits do they have to be anyway, and what must they be made of to be able to track changes between 1 and 0? Classical electronics based on silicon, even the fastest components, are too slow for the speed of state changes. Reply @hfs9502 10 days ago How can I read the answer if it disappears by measuring/reading it? Heisenberg tells me the answer is uncertain? Reply @wiserthanserpents 2 days ago (edited) we haven't unlocked the full potential of transistors you can use the same transistors over and over again to calculate and create different connections on the same transistors to make it do different calculations by changing the connections its the connections that make a circuit it not the components even though you may need them but instead of adding more you can use the same parts to do different things on one of my projects im working on creating a four bit computer using only two transistors and building a 8 bit computer using only 4 transistors by connecting them and making it go back and forth realy fast and generating an 8 bit computer Reply @byrgesen6633 2 weeks ago Music video 😢😢 1 Reply @johnd443-e9q 18 hours ago You used the NOT gate as a familiar electronic configuration in the classical computing. However, you didn't describe a the electronic configuration of a QUANTUM NOT gate. Is it not different? Is it still the same silicon? Reply @hughezzell10000 11 days ago Music didn't help in this case. So the oracle is similar to a stack of super computers, but only capable of addressing one function. I guess that isn't very convenient. Reply @tricross6 8 days ago What's with all the curvy wire/tubes? 1 Reply 1 reply @DerekDavis213 10 days ago What general-purpose problems can a quantum computer solve TODAY for business or academia, that is far superior to conventional computers? Reply @BIG-MAD 6 days ago Worst explanation 2 Reply @Italianjedi7 11 days ago Is there a limit to the amount of qubits a quantum computer can have? Reply 1 reply @JJ-lh1un 10 days ago (edited) Whatever is known about quantum computing is not being made public and it never will. If they got it to work you will see magical things happen in evil ways. Reply @stickyislands 9 days ago This video is a bit misleading 1 Reply @maxpower1337 8 days ago Help my cat might be dead and alive but I don't want to open the box he is in; Reply @APD-sl8qx 23 hours ago Why do we need this background music on these kind of videos? Just plain English is sufficient right ??? Reply @World_Class_Procrastinator 2 days ago So, yeah, I understand the conceptual idea behind how it works, but not what is actually happening. It seems there's some level of obfuscation going on, but I know there's not. Tbh though, it's not your fault. We don't work on a quantum level, so it's hard to understand just what is happening down there. It almost seems like the results calculated are emergent, which seems ridiculous, but again is just part of how it works. Very strange. Reply @paulheinrich7645 13 days ago Fleetwood Mac wrote a song on this very topic about 40 years ago. It went something like🎵🎵🎵 "... I'm over my head ... ". 🎶🎵🎵. But thanks for trying to breakthrough my numbskull knucklehead. Reply @ferroalloys594 12 days ago For goodness sake, its all a bit "decoherence-limited)" no matter (no pun intended!) as to its operation/utility! Simples, ™ (:-) 1 Reply @ktrethewey 2 days ago You still have not explained how we derive the correct answer from all of the possible answers. Nor have you explained how the problem is set up in the first place. More logic and teaching less music and fancy graphics. 1 Reply @leonardgibney2997 6 days ago (edited) The British Home Office is getting one to deal with the asylum backlog. Reply @deyshubho75 10 hours ago Pls kill that non sense back ground noise. We don’t need music for such a complex explanation. It doesn’t allows to focus at all. Reply @domenicobarillari2046 11 days ago Physicist here: my son is studying engineering and asked me to watch. Already at 4:15 there is a conceptual error. You conflate the probability spread of something like a gaussian wave packet with the notion of superposition just because the associated particle might be found in a range of locations when an ensemble of experiments is done. This is incorrect: whilst one can superpose various wave packets( configurational states) from different eigenfunctions of diverse position operators to emulate this outcome, one can have the state you show as the eigenstate of one operator. Using such an example to introduce the general idea of superposition is misleading. Good thing you technically only deal in qubits, otherwise it could matter a great deal. DKB Reply 1 reply @Apu-h7b 6 days ago AI understands , so you don't have to . Reply @gilberthernandez804 10 days ago I can also can make any numerous rediculous theories. All this video proves is that we don't know SHIT!!! Reply 12 days ago There is no quantum computer. Proof: You cannot buy one. Reply @Keystone_Investigations 13 days ago No thanks.....I will keep using my slide rule! 🙂 1 Reply 1 reply @psyphi407 9 days ago Is this another Ai generated video? Reply @aipsong 13 days ago Very clear explanation!! Thanks!!! 1 Reply @bamakeyman 7 days ago The probability that I know jack $hit about what he's discussing is very low. Reply @jesusisunstoppable4438 2 weeks ago After searching, I'm guessing a Qbit in this case is a Quantum Dot.. Makes sense. Question. Why are Quantum Computers shaped so Weirdly? 1 Reply 4 replies @Victorted 9 days ago With all the liberal arts majors out there working at Starbucks and your local car wash and willing to read a script for minimum wage, why are we all listening to computer-generated gibberish? Reply @stevelenores5637 4 days ago 😂. The number of problems solved by Q computers is exactly zero. Reply @ok-nw1sc 9 days ago The biggest nothing😂😂😂 Reply @MusangKing-b3o 6 days ago (edited) A junk science or bad science project for academic grifters, that is all to it. Reply @borisbacic3658 10 days ago AI generated video Reply @petermainwaringsx 2 hours ago I've listened yo two minutes of boring waffle, explaining how this video is going to explain how quantum computers work.I'm out of here. Reply @akbhaikasturia 8 days ago Quantum theory is fake and baseless Reply @Iliribur 13 days ago (edited) I don't think this is explaining quantum computing either. Quantum bits have a spin. We can think about it as a wave of probabilities. Once we measure it (interact with it) it will take final state: spin up or down. What makes it powerful is entanglement. While entangled, quantum bits can take many variations (take different spins simultaneously altogether). Upon a measurement (wave collapse), all quantum bits will take their final state (because system gets entangled with a measuring wave). To get desired result, special algorithms are used 1 Reply 2 replies @chevywaldo8561 9 days ago You still failed to do a good job explaining quantum computers..😢 2 Reply @niteeshkd 7 days ago Very well explained! Thank you ! Reply Top is selected, so you'll see featured comments