### Numberphile Breaks Down the Twin Prime Theory in (Mostly) Plain English [Video]

#### Wondering why Yitang Zhang's work on prime numbers is such a big deal? Because 70,000,000 is closer to 2 than you might think...

Earlier this month, we brought you the news that **University of New Hampshire mathematician Yitang Zhang proved a weak version of the twin prime conjecture**, showing that there is an endless supply of prime pairs which are separated by no more than 70,000,000. That seems like it's a long way from proving the proper twin prime conjecture -- showing an infinite number of primes separated by just two digits -- but it might not be. **In their latest video, the math whizzes at Numberphile offer a great layman's explanation of what the twin prime conjecture is and what Zhang's work means for it. **

### Kind of a Big Deal: Mathematician Proves Weak Version of Twin Prime Conjecture

The **twin prime conjecture** states that there are an infinite number of twin primes -- prime numbers where one prime is two greater than the other. For example, 1 and 3 are twin primes, so are 101 and 103, 881 and 883, and so on. This conjecture has never been proven, but **Yitang Zhang believes he has proven there are infinite primes paired with other primes no greater than 70 million more than themselves**. Here's why that's kind of a big deal.

### There’s a New Largest-Known Prime Number, and It’s 17 Million Digits Long

Quick! **What's the largest prime number you can think of?** Is it millions of digits long? If it isn't then you're nowhere near the **new largest-known prime number**. Euclid proved centuries ago that there is an infinite number of primes, but no one's ever found a formula to find them, so the process of seeking them out in numbers so large is a tedious one. So tedious that** it's taken four years to beat the previous largest-known prime**.