My understanding of quantum computers is right on the edge of what I think I ‘get’. Quantum physics has some ‘strange’ aspects to it. The most famous involves Schrodinger’s cat – which ‘enjoyed’ Super-position. That’s the ability to be in two states at once (until observed.)
Quantum computers use this feature and create structures in laboratories which do not exist in nature. The best explanation I have read is here, but it’s pretty involved.
Quantum computers can do lots of calculations at once
The maths of quantum computing goes something like this.
- A quantum particle can be in two states, either a 1 or a 0.
- Quantum particles have a feature known as ‘super-position’.
- Quantum particles can be in many states at once
- They can, therefore, calculate a lot of things in parallel.
- This is as opposed to current computers which can be in only one state at a time and must work through each permutation in sequence.
- It is possible to create a model in a conventional computer, which can describe the quantum states and run through them one after another.
- The computer just needs to be able to run through 2 to the power of n states.
- If you had 8 quantum particles, for example, you’d need a computer which can run through 2 to the power of 8 states. No worries.
- But the maths soon gets you in the world of lots of zeros.
- For example, if you add 30 quantum particles and tried to replicate the calculations on a regular computer, then you need to run through 2 to the power of 30 calculations in sequence – which is a 2 with 2100 zeros after it. Current machines would take a while to do that
Do the same thing the other way around, and you can see the value of a Quantum Computer
Considering the same setup but starting from the other end then, imagine you had a quantum computer with 30 quantum particles. It could simultaneously calculate every permutation of these 30 states. In quantum states (because it factors multiple states) you can run through the 2 x 2100 zero things with your 30 variables and complete the task much faster.
The most commonly mentioned use for this is breaking codes built around hard to ‘factor’ calculations which is what most of the world’s internet security runs on at the moment.
More generally, quantum calculation principals can be used to solve any problem which involves a lot of combinatorial factors. As in the real world example of the first company to make commercial use of quantum computing, DWave.
DWave is optimising large numbers of funds to meet the risk profiles people want. There are a large number of these in real life evidentially – any variation of the travelling salesperson calculation. Examples include microchip design and logistical route planning (which I think is actually the travelling salesperson in real life.)
Jeremy Hilton, Senior Vice President, Systems, at D-Wave says “Complex processes are all around us. By using quantum computing to operate them more effectively, we can make just about everything we do run more smoothly.” Source: Forbes.com
On one side of the coin then, you have the overnight destruction of every current form of encryption. On the other hand, there are a number of things that quantum computers can help with:
- Better marketing: Using all of our pattern matched data to generate personalised and relevant messages for us.
- Weather forecasting: Weather is a complex system which requires a lot of computing power. Quantum computing could improve it and its flows on effects, improving farmer’s ability to grow things efficiently, avoiding accidents caused by unexpected bad weather, even judging the right time for military operations.
- Better medicine: Analyzing genomes with treatments which will work well in unison with our particular (individual) genetic structures.
- Better AI: High-quality artificial intelligence seems to be a combination of the right algorithms working on vast quantities of information. More efficient training of AI algorithms could come from quantum computing doing the crunching.
- Avoid destroying the universe: We may well also be able to re-create quantum experiments within simulations. At the moment, we do those tests for real using the large hadron collider. I’m not an expert, =but since some postulate these experiments could lead to the end of the world, the simulation seems preferable.
It’s not hard to imagine quantum computers being available in the cloud for us all to use and a lot of change happening between now and when these new computers arrive. Which, some say, could be in the next 5 years.
Incredibly, Quantum computers are not the only research taking place in the world of processors. For some types of application, it could be DNA “it’s plausible to have on your desktop more processors working than exist in the rest of the planet put together.”