Why aren’t quantum computers everywhere, Mr. Feynman? 

I just started watching all your videos last month while Im working full time on a multicore quantum compiler. Timing is sometimes just perfect, thank you for your excellent content :)

Hi I am Ankit as a physics student,i think you spread a very useful information for us ,love from India

Thanks for the explanation...as someone from outside the field, this was the best explanation I've seen that wasn't too technical AND had great visualizations

Another issue with quantum computers is that the set of problems for which the best known quantum algorithm is significantly faster than the best known regular algorithm is relatively small. A qbit might technically be able to store more information than a regular bit due to allowing for superpositions, but that does not mean that we can actually use this additional information in any meaningful way and, so far, it seems like we cannot, in most cases.

I remember Feynman's lectures on computation, it was so good. I didn't understand much :)

This was both enlightening and entertaining. I'm well downstream from this channel's material, but always come away wanting to learn more.

I've been following you on RU-vid for years, and I also worked at Q-CTRL in 2020-22 (was involved with their deep reinforcement learning research, among other initiatives). So cool to see both worlds collide!!

At the Feynman's time there still existed analogue computers, which did exactly what Feynman proposed though in the field of classical physics. An analogue computer could solve differential equations almost instantly. The problem with them was accuracy of elements and incompleteness, e.g. some simple problems where hard or impossible to solve. A square root element was the size of modern computer. Inaccuracy was caused by [thermdynamic] noise like in the quantum computers. The question of completeness is an interesting one. It boils down to whether modeling physical world is all you need from and for computing. It some sense it is, because a computer exists in physical world. But the size of the model could quickly become too large, as you explained.

One small step for quantum and one giant leap for quantumkind.

I enjoy these mini documentaries! Very informative and well developed, thanks 😎

Thanks!

Hey , Darsh here . I am a student ( special a physic student ) but I use to keep interest in astrophysics as well as in psychology , to know about different phD thesis ,... I just feel wow after watching your videos , it was so amazing, Nice content creator 👏

I passed this on to my Chinese A-level Physics students. We are currently studying quantum physics in the classroom and I know that some will go on to study computing in the UK. very helpful - thank you

I really enjoy to see/hear you! Happy New Year, and a big hug from Brazil.

Quantum computers are great at Constraint Satisfaction Problems like coloring a map using a qubit for each vertex in the inverted graph representation. This means you would be able to solve for video game worlds like minecraft in a single operation rather than having to iterate thru the object. Redstone would be done in contant time as long as you had enough qubits to represent the redstone devices.

Wow, good timing! IBM just released 1000+ qubits chip this year yesterday!

"Prediction is very difficult, especially if it's about the future." -Yogi Berra/Nils Bohr

Watching a Tibees video. Way to start the day off right!!! :D

thank you for this! i no longer misunderstand superposition as both states at once thanks to you.

Morning, I've got to watch this video over and over again. Way over my head. But I'm interested.

I think your sound quality has improved. I've had trouble hearing your lovely voice in some of your past videos, which was quite frustrating, as I have very much enjoyed them.

Thank you for the informative video. I'm currently taking an introductory quantum computing course in my senior year, i've always wanted to go deeper into this area and taking the course made me want it even more. I'm even considering to pursue master's degree on quantum computing.

What happens when someone plugs a poorly written AI program into the 422 Qbit IBM Computer? (Especially considering the error correction issues?) For the record, I welcome our new computer overloads!

Hey Tibees, maybe you do a video on poncaire conjecture and its story, since you are doing a lot of stuff related to higher dimensions, etc.❤

Thanks for this clear explanation of the current state of quantum computing.

"How come cars aren't everywhere?" asked someone when the first cars came out. And it took many more years than the 42 years where you are asking "Why aren't Quantum computers everywhere" for cars to BE everywhere choking up traffic (like in LA) in ways that are unimaginable. Where there are doubts about usefulness, or use cases, this will change. So you can be "correct" by looking out at the world RIGHT NOW by saying they aren't everywhere, that is, until they are everywhere, which would then make you wrong... but, of course, that will be awhile and people will have forgotten. Convenient.

You can have floating point numbers as the the base for all computation, in which case it would probably work similar to qbits, holding a lot more information. However its usually not used because of imprecise results especially when dealing with integer computation.

Didn't understand anything Tibees was saying but watched just to hear her soothing voice.

So amazing… thank you for much clarification of the present picture of quantum computing. Awesome.

Great discussion of quantum computing.

Thou shalt not mess with Feynman!

I'm pretty sure that Yuri Manin first proposed quantum computers in 1980.

Qubits are sort of purpose specific but if you are looking for quantum technology I would say that's everywhere. I mean if you have a QLED T.V. you have quantum technology in your house right now. There is a bunch of stuff quantum phenomenon is used for right now. People use it in warehouses to efficiently find the shortest path, in traffic control, weather stations that use quantum annealing. Your bank has a quantum key encryption network setup right now some of your money may have travelled by. Some you may not have heard of include: Radar technology that uses "tagged photons" which is quantum entanglement. LIGO has squeezed light, also entangled pairs shot at a mirror. What about regular L.E.D.s? You are shifting electrons into higher and lower orbits, isn't that quantum technology too? There is radio technology that uses Rydberg atom states that makes for an incredibly wide-range super-sensitive radio-receiver called Rydberg Atom-based Quantum RF Field Probes by folks at NIST. It's everywhere. D-Wave calls their machine a quantum computer, no q-bits but dare I say is that not a quantum computer as well?

Brady Haran has videos of all the right people to explain what to do to make specific Math-Physics demonstrations of how to answer the question with specific reference-framing, and then there's Scott Aronson and his specifically qualified professional opinions about Quantum Computation.

Thank you profusely tibees, for providing awareness on the state of development of quantum computers and an in depth analysis of their function, operation and their potential incorporation into the technological/scientific infrastructure of today's world. Thank you once again, infinitely.

The clip at 0:35 is from his lecture on the scientific method, nothing at all to do with quantum computing. Just b-roll?

Another fascinating video Tibees! I’m still searching the fourth dimension

Quantum computers can't actually give you a,speed up on all classically exponential problems, just some of them. As far as I know there aren't all that many problems known to have fast quantum algorithms outside of cryptography and simulating quantum mechanics, but I'm not an expert and haven't followed the field closely.

Currently watching a series called Devs. All about the possibilities of having a quantum computer.

I can watch this all day

Not knowing something is the beginning of learning and knowledge.

What a silly title. Feynman said that quputers are *_needed_* (for certain problems). He never said we'd *_have_* them (in abundance by the year 2023)

You talk about 1981 and that being the introduction of the IBM PC, but show video of much older computers. In 1981 mini computers were widely used (DEC's VAX machines were popular). And the landscape of computing was more or less set in the 1960s, not 1981. The 1960's saw the invention of Integrated Circuits and then processors implemented on such, and the invention of UNIX, C, and a plethora of other software ideas.

With all that is going on with AI lately, I wish someone like you could explain how the large language models like ChatGPT work.

Omg I really loved the video, thanks!

Amazing. :) It's so magical to hear you...

Does Q-CTRL do any research in the Virtual Quantum Computing realm ? 😸

Loved black opal and it's pacing

Excellent video

Feynman did not propose quantum computer. Probably Paul Benioff was first who did it. Feynman did not talk about quantum computer as such, he suggested to use one quantum system to simulate another quantum system, Feynman did not manage get to the point to realize the concept of quantum computer, in fact he has never acknowledged this idea as something viable, it looks like he could not admit that he missed this development so he pretended to his end that it is just some kind of mental twist from proponents of no-collapse QM interpretations like David Deutsch & Co.

So...using a quantum computer to write "hello world!" Is a bit of over kill?😂

🎊The gap between the digital era and the quantum era is to be verified with intrigue. Noise reduction with "multiple-qubits" mode and dynamic stabilization (temperature protection) are to be noted too. Parts of the "circuit" and whats going on with the state of the qubit continue to fascinate in addition.🐰

Thank you for this video, Tibees.

Silly question: Is it possible to use a kind of known, steady quantifiable noise (like white noise when you're trying to sleep) The compensator described in the video could act like your attention, clearing out that which is predictable and repetitive.

I think you should start an Audio book series, your voice is so peaceful to listen to 😍😍

Many kinds of noise cause qubits to decohere, but one particular kind of noise is commonly overlooked. In large classical systems, time-keeping has to deal with "Jitter" - a random unevenness in the rate at which clocks tick. At the quantum level, one has to deal with "Quantum Jitter" - the inherent variation in time-keeping as first explicated by Einstein in General Relativity. We live in a cosmos permeated by gravitational fields and their associated gravitational gradients. Due to gravitational gradients, qubits separated by space are governed by their own local clocks (called "proper time"), and tiny perturbations in proper time cause qubits to progressively decohere - their phase drifts relative to their neighboring qubits, and they drift out of perfect phase-locked synchrony. The decoherence time turns out to be maddeningly brief, meaning only a very small number of computational steps can be completed before cumulative decoherence ruins the synchrony of the ensemble of qubits.

Q control looks great , I am a local (Syd AU) love to support local business.

Fascinating and so clearly explained.

Do thermodynamic computers next!

0:35 no way was that 1981. Nor was computing just taking shape. It was shaped, at least at the institutional level, we all had gazillion dollar mainframes.

But can it run Crysis?

The universe is a quantum computer.

Oh yay you’re back 👍😁

I nominate Toby to be the voice of the Quantum AI of our future. Forget Alexa or Siri. She has the most amazingly soothing voice I’ve ever heard.

Very interesting!

Has there been any research for developing or understanding how different approaches to measuring a quantum state make it more or less likely to make the state unstable? Like method 1 has a 30% chance of altering the quibit, and method 2 would have a 60% chance of altering the quibit

13:25 That's the first step for building a Heisenberg-compensator! Beam me up, O'Brian!

Obrigado pelos conteúdos que você produz. E sua voz é semelhante a um delicioso ASMR relaxante. Forte abraço aqui do Brasil.

Can u do more videos on Terrence Tao or ramanujan

I gotta ask how do you feel about that one veggie tales video being your most popular one?

Thx Toby. This is a great video. Since quantum computers require sub-zero temperatures, perhaps they may be best suited to put on future lunar missions to moon's South pole where current electronics can't survive cold temperatures, but quantum computers can still keep working during frigid lunar nights. Just thinking out loud.

nice quantum review

Thank you! 🙏

Merry Christmas ⛄🎁

I like your videos I study physics when I'm bored. Thank you.

Another quantum solution is sourcing a parallel universe moving backwards in time. Moving from higher to lower entropy is equivalent to running a quantum computer.

Thank you.

I love your videos Tibees

Are you sure that video clip (black and white) was from 1981?

Excellent video, I'm trying to understand quantum physics more and this video is so well put together. How did you make the animations? You mentioned they were from Black Opal?

See his "There's Plenty of Room at the Bottom." It's pretty consistent with SD RAM. Also consider how he approached the T-symmetry of Maxwell's equations as well as sum of histories. I conjecture from this that, no matter how quantum we make computers, they won't be faster than the Shannon entropy engines we have. The universe will always have a trick up its sleeve.

Between chemical and physical engineering, which course to choose? I want something that gives me many possibilities and financial return, in addition to being automation-proof. Initially I intend to do physics as an academic career but I'm in doubt...

Could you put a log fire in the background?

Id really like to see a conversation between tibees and Lisa Randall...would be cool to have some interviews with math olympiad gold medalist also about jow they learned maths etc

QuBits seems to be similar to idea/concept of fuzzy logic (where each state consists of a linear degree) isn't it?

That's because you could only understand anything related to quantum physics while he was talking - afterwards it reverted back to a cloud of unknowing.

Title should be "Why aren’t quantum computers everywhere, Dr. Feynman?"

Miis Tibees, I have completed your story of Bob rescuing the deer...

Maybe quantam computers are everywhere but they are in the 4th dimension so we can't see them.

Yeah, the "noise" and errors pique my interest in quantum computing. It going to be interesting how people come up with solutions. Look into quantum biology. Plants naturally do this process through photosynthesis. Nature is once again guiding us. I guess learning about the mitochondria in high school became useful after all lol.

7:55 not necessarily. If a classic algorithm is linear but its quantum counterpart is logarithmic, it's worth it

a day after ibm quantum keynote, crazy

Toby, I've seen the bad storms you are having there in your country. I hope you are ok and didn't get any damage from it. Sorry about the lives lost. Hope to hear from you soon.

Why isn't the quantum PC isolated in a vacuum? I mean, electromagnetic fields would still interact with it, and I ignore whether electricity runs in a vacuum, but if the issue is an interactive issue... of chairs in the lab, isolating the PC makes sense

Favorite guy ever.

3:25 Being pedantic here, but *current computers use "quantum mechanical principles".* Modern devices (e.g., the tiny transistors on an IC) are designed with knowledge of material science, knowledge that definitely depends upon QM. This is what is so deceptive about the phrase "quantum computers". For the latter, and that to which Feynman pondered, is to *exploit the nature of the **_superpositionality_** that QM presumes about the states of an object.* Feynman wanted to use such exploitation to better understand reality. Today's "quantum computer" industry wants to use such exploitation to massively increase the computational power for particular operations.

1:44 "Even today there's a lot of physics we still don't understand and SO we need computers to help us learn more" That was an unfounded conclusion if there ever was one... Please elaborate.

The Father of Qbits is Qbert

My problem with the popular science discourse on quantum computing is that it has all failed to give me a sense of how any of this technology can or will be applied. Show me a program running on an actual quantum computer so that I understand intuitively its inherent advantage over a classical computer

I just read an article about how physicists just quantum entangled some molecules for the first time in recorded history, although I believe brainwaves quantum entangle on a daily basis but that has yet to be proven and an entirely different, rather esoteric matter. Not only will this lead to quantum computing, it will lead to much safer encryption algorithms.