Qubits

There are 10 types of people in this world: those who know binary and those who don’t.

 

If you don’t get that joke, I suggest you read up on how binary works, because binary isn’t just a cool thing to know anymore. Practically every human alive today will interact with a computer at some point in their life. While it appears that computers understand our languages, that’s just a facade. The language of computers is binary: long endless streams of 1’s and 0’s.

As mentioned in the last video, computers process these 1’s and 0’s with transistors. The more transistors you have, the more operations you can do in parallel, equaling faster computing speed. But, eventually we will reach a limit on the number of transistors we can hold on a chip. At that point, what will be do?

The traditional system of storing information uses bits, each bit being a 1 or a 0. Supposing I had two bits, I have four different combinations: 00, 01, 10, and 11. Each combination represents exactly two bits.

Now, let’s bring in some quantum mechanics. Scientists are working on developing new types of bits, known as qubits (quantum bits). Like classical bits, the have two positions: up and down. However, these qubits can exist in superpositions, where we don’t know whether it is up or down. Essentially, it is both up and down, and we only have probabilities two predict which position it is in. That’s pretty cool, and something that takes time to wrap your head around!

Now imagine I had two qubits in superpositions. There are still four possible combinations: DD, DU, UD, UU. However, we don’t know which position each qubit is, so instead the information is represented as probabilities of each combination. That means two qubits conveys four classical bits of information. \

Scientists have found that n number of qubits convey as much information as 2ⁿ classical bits. At first, that doesn’t seem like much of an improvement, but once you start thinking of having 300 or 400 qubits, the numbers get impossibly large for a human to comprehend.

By requiring a lesser number of operations, qubits can work faster than classical computers. But is that the end of the story? Are qubits a universal substitute for classical computers? We’ll look into that in the next post.

The Moore Dilemma

Why is it that after a year, or even a few months, some new hardware is released that makes my computer obsolete? Yeah, you could say that computers are always getting faster, but isn’t there a more precise explanation?

I think the most elegant way of doing this is to refer to Moore’s Law, named after the co-founder of Intel who proposed it. Essentially, it states that the number of transistors on an integrated circuit is double every two years. According to Intel, that, in conjunction with the faster performance of transistors, means every 18 months sees a doubling in chip performance. That’s pretty cool.

The obvious question here is, how long can we keep this up? Eventually, won’t we run out of space for transistors? To answer that question, we have to look at what transistors are.

To put it crudely, a transistor is a switch with no moving parts. It can be closed by generating a potential. Each time it opens and closes, it is essentially sending some information, a 0 or a 1. Clearly, the more transistors you have the more information you can deal with (for an in-depth explanation, check out this Veritasium video. It’s fantastic.).

Right now, the size of a transistor can be measured in nanometers. 50 Silicon atoms (the things that enable the transistor to work) fit in this space. To minimize the size of a transistor, one has to bring the nodes (watch the video) as close together as possible while being able to break the switch.

Eventually, quantum mechanics will prevail (again, watch the video), and it will be extremely difficult to make transistors any smaller. Current predictions put this date at 2025. 

I first read about this dilemma a few years ago. My first question was, isn’t there a replacement for transistors? Ironically, the answer lies in quantum mechanics! We’ll look at that more in the next entry.

Exam Time Ruminations Pt. 2

The structure of my school is far from a democracy. Yeah, the stories of scary school-masters are a stereotype, but I’ve never really taken them seriously until I came to my current school. Like other schools, we have your normal principle, and while he does do much of the high-level work, he’s more of a puppet to the real master and the final decision maker. That privilege belongs to the Head of School (HOS).

First of all, let’s get something clear before I talk about what the HOS does to my school. She is only in that position because of nepotism. It just so happens that her husband is a major owner of the school. A few years back, she was the principle. She eventually left that position and created this one for herself. From what I’ve seen, she doesn’t have any qualifications or proof to show that she does belong where she is. That’s pretty significant. In a school like mine, a student’s relationship with the administration is important in determining their success.

There are two important things about our HOS. Firstly, her mind is ingrained with the image of the ideal, Indian student. She loves all those who can step into that mold, and scorns the ones who can’t, or don’t even try. Secondly, she’s a miser. She’ll jump at money making opportunities and circumvent discussions about spending it.

Above those two things is the reputation of the school, a thing both she and her husband hold with great importance. Together with her two attributes, these three things form the basis on which she makes any and all choices. Even though it’s hard to tell, she’s behind all the decisions made at my school: who’s fired and who’s hired, what trips to plan, what events to hold and how to hold them, who joins the student council, who gets an award, who gets recognized for the school’s success, everything is approved by her.

There’s no grey area with her. Those she likes are showered with praise and opportunities throughout their time at my school. The others, the ones in the ‘black,’ are insulted in front of other students and ignored otherwise. Spend just a few minutes with her and you’ll see who she loves and who she thinks is useless.

What does this mean for the school? Well, those she likes are favored to succeed. The rich kids with money to donate, and the ones who carry out her every whim and fancy are given each and every opportunity to succeed, and not all of them are legal. The rest, if they even want to, have to struggle to reach the top. In the end, all this does is create an environment where all the ‘others’ stop trying to succeed and resign themselves to coming in fourth place.

Now, you might say that this is a good system, because it’s survival of the fittest. I agree that survival of the fittest is a good policy in the workplace, because in that mechanism, both the workers with initiative and the company benefit. But in school, it is the job of the institution to ensure all the students succeed. That’s what families pay tens of thousands of dollars a year for. And while all of the HOS’s ideas may not be bad, this is definitely an imperfect system with an obvious replacement. And by replacement, I mean replacing her.

Exam Time Ruminations Pt. 1

Twice a year there comes a time in my school of wealthy kids where the majority of them actually consider picking up their books and reading. It’s ‘affectionately’ referred to as Exam Time. Don’t get the idea that any of them have very lofty goals; most are just trying to pass their subjects (50%). For some reason, the word ‘exam’ carries much more importance with them than the common test, even though both add up to give them their final grade.

Of course, their studying isn’t all that helpful. Most of it is just patchwork memorization. The kids learn formulas, but don’t really understand what they mean. One kid could easily rattle of the formula for acceleration, but couldn’t supply a simple definition of the same. Yet, even when the flaws in their revision methods are revealed, they just shrug it off. For most of them, these grades don’t matter. Their fathers have saved spots for them in the family business. The rest, those without businesses, are too ignorant to realize they have followed their wealthy friends into a trap that will mar them with regret for the rest of their lives.

Obviously, a large amount of the blame lies with the parents, who don’t bother to correct their child’s ways and mindsets. Yet a lot of it also has to do with the school’s culture…