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# Detangling Quantum Computers

Tech Talker teams up with Ask Science to explain quantum computers -- and tackle all those conspiracy theories you may have heard about their computing power.

By
Eric Escobar
Episode #107

If you've read or listened to Ask Science's episode on quantum computing, you probably find yourself left with more questions than answers. You're not alone. Quantum computing is such a complex idea, it stumps even the brightest scientific minds.

But for our practical purposes, the main question is: How is a quantum computer different than your laptop or desktop?

Well, a normal computer uses bits (1's and 0's) which are generally stored on transistors. Normal computers use bits to execute code, store pictures, play music, check Facebook, and pretty much everything you can think of. Quantum computers store their information as qubits or quantum bits. Quantum bits are pretty tricky, because they can be a 0, or a 1, or both! This is called superposition.

This property allows for some pretty exciting things in the world of programming and mathematics. This third state that a qubit has is not observable. In fact when you do observe it, it turns into a 0 or a 1. Kind of like when you open the refrigerator door, the light always comes on. There's no way to see the inside of the dark refrigerator..

## Super-What?

Quantum computers use this breakdown of superposition to do some really interesting calculations that normal computers have a really hard time with.

For example it's really hard for normal computers to find factors of prime numbers, and it just so happens that almost all cryptography uses some form of large prime numbers or one way functions to secure your data.

In fact you use this hundreds of times throughout your day as you log in and out of websites. If I were to try and break your password I would just have to guess a bunch of times until I got it. With a quantum computer, as the state of the superposition breaks down so does your password.

This could also affect the world of Bitcoin and other cryptographic technologies. Because what was once a hard problem to solve is now pretty simple to break into!

Now don't worry just yet. There's nothing publicly known that can break passwords in the blink of an eye! There are quantum computers that can only use a few qubits to do very simple computations. In the future though this may lead to some really interesting shifts in technology!