What is the Most Complex thing in the Universe?

What is the most complex piece of creation (natural/artificial) in this universe?

Is it the human brain?

But if the brain is so complex, how could we do relatively simple tasks such as waving a hand, run, type, wash clothes, handshake, et al with ease. Well, the same brain could understand & do more complex tasks such as tying the shoe laces, complex calculus, string theory, quantum mechanics, read and write stories, poetry, emotions and other such activities. The brain can comprehend the vastness of our "observable" universe and yet be oblivious to the infinities beyond it. Coordination between the senses is another marvelous achievement of the brain. And the brain can think about itself.

How does the brain work?

While scientists are still trying to fully understand the brain by dividing the brain into different parts and understanding each part separately, we still remain ignorant of how the brain coordinates all of its activities and develops language, thought and a sense of self. These activities are controlled by "neurons".

There are around 100 billion of these "neurons" in our brain (more than the stars in our galaxy), with each having 1000 to tens of thousands of connections with each other. These neurons communicate with each other through electrical signals. For each of our task, thousands of neurons could get fired. A graphical representation could be seen below.

With all these connections, they act as a switch and there are nearly 125,000 switches possible in the brain. That's 'Yuuuge'! With the current computer hardware, it would take thousands of years to simulate the complex functionality of the brain, if we can do.

I love the "Matrix", the movie. Do you?

The story revolves around a man named, Thomas A. Anderson, aka neo, who is a man living two lives (by day he is living in a computer generated matrix as a programmer but at night he tries to find who he really is). Neo has always questioned his reality, but the truth is far beyond his imagination. Neo finds himself targeted by the police when he is contacted by Morpheus, a legendary computer hacker branded a terrorist by the government. Morpheus awakens Neo to the real world, a ravaged wasteland where most of humanity have been captured by a race of machines that live off of the humans’ body heat and electrochemical energy and who imprison their minds within an artificial reality known as the Matrix. The story then proceeds to showcase the struggle of Neo to return to the Matrix and confront the agents: super-powerful computer programs devoted to snuffing out Neo and the entire human rebellion.

The first time I saw the movie, I was in awe. I was fascinated. Like many others, I asked myself the same question - "What if I am too living in a computer program". Many geniuses of our times and before have had the same question but none can answer it. Maybe, even the brain has limits, after all it can't store infinite amount of data or has infinite amount of computing power.

So, How much data our brain could store?

If each neuron could only help store a single memory, running out of space would be a problem. You might have only a few gigabytes of storage space, similar to the space in an iPod or a USB flash drive. Yet neurons combine so that each one helps with many memories at a time, exponentially increasing the brain’s memory storage capacity to something closer to around 2.5 petabytes (or a million gigabytes). For comparison, if your brain worked like a digital video recorder in a television, 2.5 petabytes would be enough to hold three million hours of TV shows. You would have to leave the TV running continuously for more than 300 years to use up all that storage. Wow! All this should need a reliable and never ending power source.

So, How much power does brain consume?

Brain is only 2% of the body by weight but consumes around 20% of the power. It consumes around 20 watts of energy, enough to power a small electric bulb. Now, compare that to the computers and the supercomputers of today. That's efficient. Learning so many things with so less power should be difficult for the brain.

So, How does the brain learn?

Learning is a tedious process. How we learn something and learn to be good at it? – Repetition. Repetition of a task, whether solving math problems or playing soccer, or lying, or throwing a ball, or talking, or writing letters, or listening, or seeing, gradually instills long-term mental and muscle memory.

But did we learn breathing? No, must be the answer. Then how come we started breathing right after we were born. Not so easy to answer. Right? A simple answer would be – we humans are wired that way and it is passed from one generation to another through genes. But that’s not all. What if I tell, we might have learnt this from our mother, while we were in the womb through passage of electrical signals, giving necessary learning to start a life. A child is born with the most basic intelligence that it needs to survive and therefore a human baby needs the care of its parents until it reaches a certain age. It is by repetition that our brain trains itself and then becomes good at doing it, often without us knowing it.

I work in the area of Machine learning and I believe that we probably use this probably dozens of times a day in our daily tasks without even knowing. For example, we learnt to recognize our parents' voice, our siblings' voice, their faces or drive a bike/car/airplane, cross a road, swim by doing that again and again. We trained ourselves on that data, iterated on it, and became better. Scientists have now come up with a new area of computer intelligence - "Deep Learning" which tries to mimic a close reality of how our brains might actually learn.

Our brains might not name the species of the cat and dog above, but it can surely differentiate and filter out required information from the pictures above. It can conclude without learning that these two are not the same animal, they are different.

Scientists have theorized the neural connections present in our brain to come up with an artificial neural network and with it the artificial intelligence. The artificial neural network looks like the one below where the network takes some input samples and provides output. What happens in between is the crux of how these networks learn.

Google recently developed an neural network and let it understand Youtube videos and the network could understand and find cats without even being told. For the moment, the extent of artificial intelligence is within the limits of our human intelligence, but who knows how much longer? What do you think?