Quantum Computing Qubit Explanation

Cause Before Symptom - With Your Host James Carner

Quantum Computing Qubit Explanation

I am sure by now you are hearing about Willow, Google’s state of the art 105 Qubits computer chip. On their website, it states, “Our new chip demonstrates error correction and performance that paves the way to a useful, large-scale quantum computer. The first is that Willow can reduce errors exponentially as we scale up using more qubits. This cracks a key challenge in quantum error correction that the field has pursued for almost 30 years. Second, Willow performed a standard benchmark computation in under five minutes that would take one of today’s fastest supercomputers 10 septillion (that is, 1025) years — a number that vastly exceeds the age of the Universe.”

The Willow chip is a major step on a journey that began over 10 years ago. When I founded Google Quantum AI in 2012, the vision was to build a useful, large-scale quantum computer that could harness quantum mechanics — the “operating system” of nature to the extent we know it today — to benefit society by advancing scientific discovery, developing helpful applications, and tackling some of society's greatest challenges. As part of Google Research, our team has charted a long-term roadmap, and Willow moves us significantly along that path towards commercially relevant applications.”

Errors are one of the greatest challenges in quantum computing, since qubits, the units of computation in quantum computers, have a tendency to rapidly exchange information with their environment, making it difficult to protect the information needed to complete a computation. Typically the more qubits you use, the more errors will occur, and the system becomes classical.”

Willow’s performance on this benchmark is astonishing: It performed a computation in under five minutes that would take one of today’s fastest supercomputers 1025 or 10 septillion years. If you want to write it out, it’s 10,000,000,000,000,000,000,000,000 years. This mind-boggling number exceeds known timescales in physics and vastly exceeds the age of the universe. It lends credence to the notion that quantum computation occurs in many parallel universes, in line with the idea that we live in a multiverse, a prediction first made by David Deutsch.”

But 105 Qubits is nothing compared to Canadian company D-Wave. D-Wave quantum chips have over 2,000 Qubits. D-Wave implements quantum annealing, while Google has digitized adiabatic quantum computation. A Graphic Card has more Cores than a CPU. There are "Annealing QPUs" and "Universal QPUs" as explained above, an incomplete list is offered on Wikipedia's page: "List of Quantum Processors".

Gobbily goob wibbly wobbly bobbily boop. That’s all you heard right? Qubits are made by manipulating and measuring quantum particles, such as electrons, photons, or trapped ions. The particles' charge or polarization represents 0 and/or 1. Qubits are different from bits because they can exist in multiple states, including a superposition of both 0 and 1. This ability is essential for quantum computers to function. Qubits use quantum mechanical phenomena like superposition to process information faster than classical systems. In a quantum computer, particles are placed in a controlled environment to protect them from outside influences. For example, they might be trapped in a vacuum chamber by electric fields. Lasers can then cool the particles and operate the qubits. Gobbily goob wibbly wobbly bobbily boop. That’s all you heard again right?

A qubit is a two-state (or two-level) quantum-mechanical system. Qubits can exist in multiple states at once, simultaneously equal to both 0 and 1. This is called superposition, and it's a quantum version of a probability distribution. Theoretically you have a bit that is called 1 and another bit that is called 0. A bit is just either 1 or 0. But a qubit can have a value of 0, 1, or both. The chip is designed with specific circuitry that can control the quantum state of the qubit, often including tiny loops of superconducting wire for superconducting qubits. Microwave pulses are sent through the chip to precisely manipulate the qubit's state, allowing for operations like flipping between 0 and 1 or creating superposition states. To extract information from the qubit, a measurement process is used to determine its state after computations are performed.

Imagine a regular computer bit like a light switch: it can be ON (1) or OFF (0).

A qubit is like a spinning coin.

* Regular bit: Like a switch, it's either ON or OFF.
* Qubit: Like a spinning coin, it can be Heads (1), Tails (0), or spinning in the air (both Heads and Tails at the same time!).   

How do we make a qubit on a GPU chip?

It's tricky! Scientists use super-tiny things like:

* Superconducting loops: Imagine a tiny wire loop that electricity can flow through. The direction of the electricity (clockwise or counterclockwise) represents the qubit's state.  
* Trapped ions: Imagine tiny atoms (like charged LEGOs) held in place by electric fields. The way these atoms spin or vibrate represents the qubit's state.

Why is this hard on a GPU chip?

* Space: GPU chips are already packed with tiny transistors. Finding room for these delicate qubit systems is like squeezing a whole playground into a shoebox.
* Temperature: Qubits are super sensitive to heat. GPUs get hot! Scientists need to find ways to keep the qubits incredibly cold to make them work.  
* Controlling the qubits: Making a qubit is one thing, but controlling it (making it spin the right way) is another challenge. Scientists use lasers and microwaves to carefully manipulate the qubits.  

Important Note: This is a simplified explanation. Making qubits is incredibly complex and scientists are still learning how to do it effectively.

Imagine a GPU chip as a super-tiny playground.

* Building Blocks: Instead of transistors, we need to build special structures for our qubits.

* Superconducting Loops: These are like tiny, circular wires made of a special material. When cooled to incredibly low temperatures (colder than outer space!), these wires can carry electricity with almost no resistance. The direction of the current flowing in the loop (clockwise or counterclockwise) can represent the qubit's state.   

* Trapped Ions: Imagine tiny atoms (like charged LEGOs) carefully placed and held in place by electric fields.The way these atoms spin or vibrate represents the qubit's state.   

* Creating the Structures:

* Superconducting Loops: These are made using advanced techniques like photolithography (similar to how they make regular computer chips, but with much finer detail).
* Trapped Ions: This involves creating tiny "traps" using electrodes on the chip. These electrodes generate electric fields that can capture and hold individual atoms.   

Key Challenges:

* Finding Space: GPUs are already packed with millions of tiny transistors. Making room for these delicate qubit systems is like trying to build a playground inside a matchbox.
* Extreme Cold: Qubits are incredibly fragile and need to be kept at temperatures close to absolute zero (-273.15 degrees Celsius) to work properly. This requires specialized cooling systems that are much more complex than those used for regular computers.   

Why GPUs?

GPUs are already masters at handling many calculations simultaneously. By integrating qubits onto GPUs, researchers hope to harness this parallel processing power for quantum computing, potentially leading to even faster and more powerful quantum computers.  

Important Note: This is still a very active area of research. Scientists are still exploring the best ways to create and control qubits on a chip.

Now let’s dumb it down so we understand how this stupid little thing works. Image a pipe with two valves on either side. The pipe on one side can be open and the pipe on the other side closed. The open side is called on and the closed side is called off. One pipe, two valves. Traditional computer chips can only open and close one or the other valve as energy goes through it. Traditional chips can only send energy one way and has two options. Open the energy through or close it. On or off. Both valves on the pipe on a traditional computer act together when the open and close is executed. A quantum qubit computer chip can send the energy through the pipe both ways at once and can open and close both valves of the pipe separately instead of them acting in unison.

See image 1



Notice there are two valves. They both are not independent and can only both close on and off. Data can only go through the valve from the left to the right. A computer chip has billions of billions of these. Each one just turns on or off. That’s it. Software tells the valves to open or close.

See image 2



Notice the data is now flowing both ways. It no longer is flowing from the left to the right but now it can evenly travel back and forth instead of just in and out.

See image 3



Now, image a camera is taking a picture of each calculation and recording how fast the data computes. The data now travels both ways and the two valves have 4 scenarios it can pass through.

See image 4



Snap one the right valve is on and the left valve is off. This is one computation in one of billions of pipes inside the chip.

See image 5



Snap two, the left valve is in and the right valve is off. This computation is recorded as number two snapshot.

See image 6


Snap three both valves are closed.

See image 7



Snap four, both valves are open. Keep in mind the data can freely travel back and forth instead of going in the chip and out with the computation.

See image 8



The chip takes the 4 snapshots and analyses each computation based on timing. The one that solves the computation is picked.

See image 9



In this case, Snap 3 solved the problem faster than the other 3 snaps. This information is then picked as the right calculation and moves on to the next set.

See image 10



The computation of snap 3 which the data was sent back and forth from recorded the better result of the 4 total. Keep in mind, the data that went through this pipe is just one bit. A 1 or a 0.

This pipe is a crude and simple explanation of billions and billions of other pipes that are connected to formulate the answer. In this case, if we were to pass a bit through the pipe, the answer would be 0 out of 4 choices. When before on image 1, you only had one choice to open or close that valve.

Now that you understand that quantum qubit processors are flipping a coin and picking an answer of 1 or 0 based on 4 choices on its own, when a traditional computer would just open or close the valve based on what it was programmed to do, you can see why they are excited about the results. Scientists and engineers do not know why the computer chooses what it chooses. They created the chip to flip a coin.

And the excitement they have with this technology is that it is wrong more often than it is right. They can’t explain why this is happening other than quantum entanglement. They think this is the new generation of computing and are going to solve this problem. The computer chip is not reaching out into another realm physically. Rather, it is programmed to, flip a coin and choose randomly a 1 or 0.

A qubit is a place in the chip that takes these photographs or flips the coin. Over the past 20 years, man has been able to squeeze 2,000 of these into a single chip. Google just created one that has 105, but it is different than their competitors. It computes differently.

Google uses digitized adiabatic quantum computation and D-Wave uses quantum annealing. What is the difference between quantum annealing and digitized adiabatic quantum computation? D-Wave is less restrictive and actually takes longer to flip the coin. D-Wave flips the coin up higher than Google does. Image two people standing next to each other flipping a coin. Google’s machine flips it a foot up and catches it quickly, while D-Wave chucks it so far into the air you can’t see it giving the odds of a solution even higher.

So in this case, it doesn’t matter how many qubits you have in a computer that makes it faster, what matters is how you judge the best performance between 1 qubit or infinity. We do not know where the sweet spot is. Google is claiming they found it at 108. And to make their sales and marketing advertisement appealing, Google claims that their Willow quantum chip can perform a computation in under five minutes that would take a supercomputer 10 septillion years. Here's what it means:  

* Demonstrating Quantum Supremacy: This achievement is a strong indication of "quantum supremacy" – the point where a quantum computer can solve a problem that is practically impossible for even the most powerful classical supercomputers.   

* A Milestone in Quantum Computing: It showcases the immense potential of quantum computers to tackle problems that are currently beyond the reach of classical technology. This has major implications for fields like drug discovery, materials science, and artificial intelligence.   

* Highlighting Willow's Capabilities: The statement emphasizes the significant advancements made with the Willow chip in terms of reducing errors and improving performance.   

Important Note:

* "Quantum Supremacy" is a term that has been debated. Some argue it's more about demonstrating a quantum advantage in specific tasks rather than an overall superiority.   

* The specific computation used for this benchmark is crucial. While impressive, it's important to remember that this is a specific task designed to showcase quantum advantage. Real-world applications of quantum computers are still under development.

In essence:

Google's claim about Willow signifies a major step forward in quantum computing. It demonstrates the potential of these machines to revolutionize various fields, although significant challenges and ongoing research are still necessary to fully realize their potential.  

All of the fancy words and hype is just for sales. Quantum computing doesn’t really change anything other than try and speed up during a time when the calculations are having trouble coming to an answer. The machine is programmed now to just make a guess and so far, the average quantum computing system is considered "more wrong than right," meaning that while it has the potential for significant advancements, the current error rate is quite high, with typical quantum computers experiencing an error roughly every 1,000 operations.

So if the calculations are wrong, then why bother going in this direction? Because it makes money and gullible companies purchase these machines thinking they will be beneficial. Also, the machines do not communicate with the spirit realm. The idea that quantum qubits can access data from other dimensions is another sales gimmick. Flipping a coin and using fate or chance is just like a casino. D-Wave and Google’s willow are nothing more than just glorified slot machines.

In quantum qubit computing, the energy flow primarily involves the manipulation of the energy levels within atoms or subatomic particles like electrons, where the different energy states represent the "0" and "1" values of a qubit; this manipulation is achieved through controlled application of electromagnetic radiation like lasers or microwave pulses, allowing the qubit to transition between these energy levels. 

Key points about energy flow in quantum computing:

* Qubit states: 
A qubit can exist in a superposition of both "0" and "1" states, which means it can occupy a combination of different energy levels simultaneously. 

* Controlling energy levels: 
To manipulate a qubit, researchers use precise energy pulses to excite the system from its ground state (representing "0") to an excited state (representing "1"). 

* Cryogenic cooling: 
Most quantum computers require extremely low temperatures (near absolute zero) to maintain the quantum states, which is achieved through cryogenic cooling systems. 

* Different qubit implementations:

Depending on the technology, qubits can be realized using different physical systems like trapped ions, superconducting circuits, or photons, each with its own specific energy level structure.

The nerds will get mad at me for dumbing down their precious computer chips, but I can’t help but expose this bullshit. Quantum chips use a different flow of energy which when cooled which can change the properties of the energy they use. Like expanding and contracting the atoms. They think that this changes the answer from 1 to 0 through entanglement. Meaning an atom can exist in two places. This is their argument for digging into this phenomenon.

source

https://blog.google/technology/research/google-willow-quantum-chip/
https://quantumcomputing.stackexchange.com/questions/1428/is-googles-72-qubit-device-better-than-d-waves-machines-which-feature-more-th