Quantum Computing Simply Explained

Brief Summary

The computers we use today (Classical Computers, CCs) use transistors which can be off or on, 2 states, ‘go and no go’ or 0 and 1. Quantum (Quantum means the smallest possible unit of any physical property) Computers (QCs) use cubits relying on subatomic particles, ions, photons, electrons and atoms.

QCs are based on quantum physics, quite different to normal physics and can be off or on and both at the same time! The problem with CCs is the miniaturisation of transistors has reached a size limit of about an atom. So it’s substantially the ‘end of the road’.

The power of QCs grows by the square of the cubits whereas CCs grow by a linear progression of bits. This means if we have 4 bits, the power is 4 times that of 1 bit. With 4 cubits, the power is 16 times 1 cubit (4 squared). QCs have got to 253 cubits so far, but they need to grow much more.

The key difference is QCs can solve problems by trying all possibilities at once. However, CCs do it one at a time or sequentially, which for very complex problems is way too slow.

This Video Explains Clearly the Promise of QCs

https://youtu.be/DUg9GvRHQk0

This video is also useful:

Problems CCs Can’t Solve

An example is fertiliser production. 3% to 5% of the world’s natural gas is used to manufacture fertiliser at a total production cost of $US100Bn to $US300Bn every year. Scientists know there is a more efficient, cleaner way to do it, but it would take 800,000 years to develop it with a Super CC, only 30 minutes with a QC.

There is one problem in drug development for curing a particular disease by analysing all the molecules in the human body. It would take 5 trillion trillion trillion trillion years with a Super CC. Don’t think we can wait that long! Again only 30 minutes with a QC. For explanation, watch the video above. It is excellent, although doesn’t deal with the difficulties in making QCs work well.

Consider finding a needle in a haystack. CCs would spend ages exploring every minute space. QCs would explore every space simultaneously and find it quickly!

Where QCs will be Used

QCs will solve problems CCs never will. Recently a QC solved a problem in 2 days that the world biggest Super CC would take millions of years. However, we will always have CCs for the tasks we all do now.

• Weather Forecasts: This could be a godsend! Nearly 30 per cent ($US6 trillion) of the US GDP is affected by weather, such as food production, transportation, retail, etc. To improve forecasts, QCs can process the massive amount of data quickly. By the time CCs do it, the weather has already changed! Also, quicker more accurate forecasts would help prevent disasters and create more accurate climate change models.
• Cybersecurity: NSA (USA’s National Security Agency) has begun introducing quantum resistant cryptography methods to prevent hacking. It plans recommending a quantum cryptography standard by 2022. Existing systems would be hacked in an instant! Much work to be done.
• Financial Modeling: QCs, can generate billions of dollars in operating income for financial institutions. They can better manage uncertainty. Also portfolio optimization, risk analysis, fraud detection, asset pricing, and capital allocation.
• Artificial Intelligence: The world now is all about data and QCs will speed up the analysis dramatically.
• Drug Design: QCs can analyse complex molecules for drug development, study interactions between the drug and its target, greatly reducing development time. Diagnostics, medications and vaccines are more accurate, coming sooner to market.
• Climate Change: QCs will tackle climate change differently. Among early applications, modelling molecular interactions involving 50 to 150 atoms, something that CCs cannot do. This could reduce emissions and enable more robust carbon capture and storage that works. It could develop lighter and stronger materials for cars and aircraft, reducing fuel and maintenance costs.
• Human Consciousness: Recent studies point to brain activity, synapsis, neurons, etc., behaving like quanum mechancis, but at normal temperatures. Watch this space.

The Bottlenecks

Quantum physics is very unstable and can misfire for many reasons. To increase stability, QCs need to be cooled to near absolute zero (-273 Deg C) or controlled by lasers, which cool and stabilise atoms. Both are expensive and difficult. However, QC power usage is very low. Bitcoin miners (and the world) would love it!

The Main Developers of QCs

As of July 2021, China appears to be ahead but Google, IBM, Microsoft and Amazon (the usual suspects), are not far behind. While China’s computer has about 66 cubits, MIT says they now have one with 256 cubits and IBM claim they will have a 1000 cubit model by 2023. There are other companies developing QCs, such as:

• Zapata Computing
• 1QBit
• QC Ware
• D-Wave Solutions
• Honeywell
• ColdQuanta

Time Crystals

In the last month, Google has discovered ‘Time Crystals’ for use in QCs. “Time crystals want to be coherent. So putting them inside a quantum computer and using them to conduct computer processes could potentially serve an incredibly important function: ensuring quantum coherence” They operate between states without using any energy! Read Reference here or below.

References

Singularity Hub

Boston Consulting Group

Harvard Business Review

CB Insights

Time Crystals

IBM