Have you ever noticed that people speaking Spanish sound like they're talking really
fast? Does this mean they are able to communicate
information faster than English speakers? One reason why Spanish sounds so fast is because
more syllables are spoken per minute than in English. However analysis has shown that
each Spanish syllable contains less information than each English syllable so the information
per minute is almost identical. But what about written language? The square
format of Chinese characters appears to fit better into our central visual field than
the longer, slimmer words of English. This led linguists to suspect that Chinese would
be read faster than English. But experiments show that English readers can perceive seven
to eight letters at once, compared to just 2.6 characters for Chinese. However those
Chinese characters are denser in meaning than the English letters and so both languages
have basically an identical reading rate of 380 words equivalent per minute.
This suggests that what limits the speed of our communication is not language but our
cognitive ability to process information. But how can you really quantify information?
Well the smallest amount of information you can have is the answer to a yes/no question,
like have you seen the movie Frozen? Yes or no, heads or tails, we can represent
this single outcomes with a one or a zero. One binary digit - it's one bit of information.
A roll of the dice has six possible outcomes so three bits of information are required
to cover all the options. To uniquely represent all 26 letters of the
English alphabet requires five bits of information. But if you include lower case, punctuations,
specially characters and number, that takes the total number of symbols to 95. So you
actually need seven bits of information to encode all these symbols.
That was first done in 1963 as the American Standard Code for Information Interchange,
or ASCII for short. Now as the next closes power of two, computers
adopted eight bits as the fundamental unit of computation, and they called it the bite,
where they intentionally replaced the i with a y so that it couldn't accidentally be confused
with a bit.
So how much information does it take to make you? Well your entire genetic code is contained
in the sequence of four molecules, represented by the letters T, A, G, and C in your DNA.
Each of these four options can be encoded by two bits of information. And multiplying
by the six billion letters of genetic code in your genome, and dividing by eight bits
per byte, that yields 1.5 GB of information. So you could fit your entire genetic code
on a single DVD with room to spare. Now your body has an estimated 40 trillion cells in
it and each one contains a full copy of your DNA. So you actually contain sixty zettabytes
of information. That's sixty followed by 21 zeroes.
Just to put this in perspective, by the year 2020, all of the digital information in the
world is estimated to be equal to forty zettabytes of information. You could store all of that
on 100 grams of DNA. That is less than you have inside your body.
But now consider this, you share 99.9% of your genetic information with everyone else
on Earth, meaning that less than one part in a thousand is unique. So the information
that makes you you could be stored in less than a megabyte. You could put it on one of
these, a floppy disk, in case you don't know what that is.
In contrast video can contain a lot of information. To specify the colour of each of two million
pixels thirty times a second for this entire video would require 100 gigabytes of information.
But you can watch this video in HD on Youtube with just a thousandth that amount. Now the
reason you can send such a big video with such a small file size is because video, like
Spanish, has a lot of parts that are redundant. Hey Michael, you know what I've been thinking
about. What have you been thinking about Derek?
Information. Go on.
It's a physical thing. It's embodied in actual objects.
How's that? Well you know like the words we say, they
are actual vibrations in the air, right? They're not just concepts. They are real physical
things that you could measure and detect. That's true and they don't go away, they don't
disappear even after they've, for instance, moved through the air.
Right. After we've said these words, they have actually interacted with everything around
us. So you're saying that technically, I could
look at the world and if I knew enough about it and the position of its particles, I could
trace back and extrapolate all the information that's ever occurred through them or at them?
That's right. You could in principle figure out exactly what we've said here, today.
Woah. This episode of Veritasium was inspired by
the book The Information by James Gleick. And you can actually download this book for
free by going to Audible.com/Veritasium or you can pick any other book of your choosing
for a one month free trial. Audible is a leading provider of audiobooks with over 150,000 titles
in all areas of literature including fiction, non-fiction, and periodicals. Now if you've
already read The Information you may want to check out Surely You're Joking Mr. Feynman
by Richard Feynman. It's my favourite book by a scientist. It is absolutely hilarious
and you will thank you for downloading it. So go, check it out. I want to thank Audible
for supporting me, and I want to thank you for watching.