It's time to go back to Back to the Future II. Back to Back to the Future II because we are now in the future of Back to the Future Part II. Today, October 21, 2015 is the day that Marty McFly arrived with Doc and his magic-ky science-y time travel car after traveling 30 years into the future in the classic hit film Back to the Future Part II and, yes, that makes me feel super old, also sad because we still don't have flying time-travel cars.

But Back to the Future made a lot of other predictions about what kinds of technology would be available by now, so how'd they do? Better than you might think. The thing is, not every field advances at the same rate. In some areas, we are actually ahead or where the movie said we'd be and, in others, not so much. The fusion-powered flying cars, for example.

(Intro)

(0:49)
Let's start with the stuff from Marty's future that we have. It's not so surprising that Back to the Future predicted a lot of this stuff because it actually existed when the movie was made in 1989, and they were all made possible by sophisticated, high-speed electronic information handling based on the same fundamental technology: the silicon microchip. Google Glass, cell phones, biometric scanners, even your TV, they've got microchips in them.

Video calls on the internet: those would not be part of you everyday life if there weren't computers powerful enough and fast enough to use them, and if those computers weren't in businesses and homes.

We have a couple of things that Back to the Future didn't see coming, just little things like cell phones and the internet, and those things were around in 1989. Now the first commercially available mobile phone went on sale in 1983, sure it weighed almost two pounds, but it was out there.

Since 1969 and definitely in the 1980s researchers were already making use of ARPANET which was like the starter Pokemon version of what would eventually evolve into the internet. So that's what we have, that's where, if anything we exceeded Back to the Future optimistic version of 2015.

(1:48)
The silica microchip has revolutionized the world we live in, not that the microchip is the only thing we needed to make this technology happen. Take video conferencing as an example. To become as cheap and wide spread as it is now we didn't just have ta solve hardware problems.

It wasn't just creating a powerful enough microchip, or launching satellites, we also had to solve software problems like how to send live video and audio data, which is a huge amount of data two ways between two computers.

This happened with the invention of network voice protocol in 1973. NVP would eventually evolve int VOIP, or 'voice over IP': the system we still use to video conference today.
(2:22)
This was huge, see conventional operates via circuit switching. Basically when you call someone a connection is made between your phone and their phone along actual wires that stays open for the duration of the call. Its got a circuit because your connecting two points in both directions. It used to be done on copper wires, now it is done on fiber optic cables.

Both are really wasteful because the line stays open both ways even when you're not saying anything so it's just sending silence. NVP and VOIP use packet switching instead, which means they only send data when there is data to send. If you are not saying anything the connection closes. If you don't move it doesn't send any new video information.

When you do talk they make what is called packet of that new data and open a connection just long enough to send it through. It's way more efficient and it means that the connection has to handle way less data. Video call wouldn't be possible without packet switching technology.

And in order to have things like cell phones or wearable computer glasses we had to develop and effective power source to run them on. (3:14) The Private Eye computer glasses that were invented in 1989 needed a battery that you carried around in a backpack, that was never going to take off. Now Google glass runs off a lithium polymer battery that fits into the stem of the headpiece. 

High-end lithium-ion batteries have about twice the energy density of any other kind of battery, but the really didn't catch on until the 21st century because lithium explodes like all the time. It's a volatile metal it took decades of testing to develop protection circuits that would make lithium-ion batteries safe to use.

(3:41)
Modern lithium-ion batteries have built in serge protectors overcharge protection and a vent that releases and build-ups pf explosive gas. Packing all that into a tiny battery was a major engineering hurdle. And every once and a while they still blow up, but that's the stuff that we do have now. let's get back to Marty's Future and take a look at the fields where we've fallen short of the future from the movie because no other field has grown as fast as electronics and computing technology.

(4:04)
We've made allot of progress in the last 26 years, but the progress has not exactly been symmetrical. The movie imagined a future where every aspect of the world we live in would be way more advanced than in 1989. With gadgets and computers we got that, their stuff, not so much.

We are going to get to the flying cars eventually, but first let's talk about medical technology.

Back to the Future predicted that we would have so called rejuvenation clinics, a place where Doc could go get his blood changed out and add 30 or 40 years to his life. That sounded preposterous for most of the last 30 years. But it turns out that it may be actually a thing.

A 2014 study in the Journal of Nature Medicine shows that injecting the blood of your mice into old mice dramatically improved their synaptic Plasticity, the connections in their brains responsible for learning and memory got stronger.

The old mice also experienced a burst of brain cell growth, as well as increased activity across the hippocampus, the part of the brain that begins deteriorating fist with old age. 

they also had three or four times as many new neurons as untreated old mice. Other studies have shown that young blood activates stem cells in old mice, allowing them to heal wounds faster, much like a younger animal. At the same time young mice then given old blood become sluggish, have difficulty remembering things, and heal more slowly

(5:09)

The reason for this appears to be the increase and decline of certain protein in the blood. Old mice, like old humans, have high levels of a protein called CCL11 in their blood. if you inject CCL11 into young mice their learning and memory declines.

B2M, a protein that peaks in the blood of old mice, and old humans, also impairs memories of young mice hen it's injected. Scientists that study aging now believe that among the hundreds of substances found in blood there are protein that keep tissue youthful, and proteins that make them more aged.

Scientists have proposed that when we are born our blood is full of proteins that help our tissues grow and heal, then when we get older, the levels of those proteins drop. that might be because the tissues that produced them just wear out.

Whatever the reason as the young making protein dry up from your blood, your body starts to deteriorate. So it maybe having your 'blood changed' can effectively younger. though you'd need to keep getting new injections since your blood cells are constantly being replaced.

(6:01)
But this is all very new science, which is so far only been tested n mice, so please don't go around doing anything weird like buying up young blood when you get older. Give the science a couple more decades to catch up with the future in the movie.

Back to the Future also predicted a world where bionic implants were common. Like the guy with eye implants that would have given him x-ray vision if they were not on the fritz, or the major league baseball pitcher who got suspended for playing with an improper calibrated bionic arm.

The word 'Bionic' means an interface between biology and electronics, or technology that tries to imitate life. 

And in the 30 years since Marty traveled through time we've come up with some pretty cool bionics. We have prosthetic limbs that you can control with you mind, cochlear implants that provide sound information to your brain, and artificial hearts that doctors can plug into your chest to pump you blood for you.

Bu we don't have the kind if sophisticated bionics we hear about in the movie. Why? Right now the most innovated technique we have for prosthetics involved rerouting the nerves with a procedure called targeted muscle re innervation. So if you wanted like a bionic arm they would dissect you shoulder and actually pull out the major brachial nerves that normally go down your arm and put them back into your chest.

Your prosthetic arm would then have electrodes that would fit over those relocated nerves to pick up the signals from you brain. Because you brain thinks those nerves are still in you arm, even if you don't have and arm anymore. So if it tells your arm to bend at the elbow that signal would go to your chest and be picked up by and electrode, which would relay the information to the prosthetic. 

But this only works for major muscle motions, we currently just don't understand how thought becomes tiny complex movements well enough to be able to turn that into mechanical data. 

(7:30)
The next step will involve neural implantation, which is sticking sensors into your brain. that is dangerous and complicated and still very experimental, but those experiments are happening.

In December of 2012 at the University of Pittsburgh Medical Center a 52 year old quadriplegic was able to control the movement of a robotic arm through brain computer interface technology, thanks to having two computer chips implanted in the motor cortex of her head. But there is still work to be done, for one thing, we have to make sure its safe before we roll that out on the market. 

(7:59)

Now, flying cars. Yeah, flying cars. There are two of them currently in development, the Terrafugia TFX and, and the AeroMobil. The TFX uses collapsible, kind of concealable battery-powered rotor blades to lift off and move in to a gasoline powered propeller like fan for thrust.

The twin collapsible propellers fold under the car when it's a car. When it's not a car it looks like a weirdly car like helicopter. The good news is that operating the TFX will not require a pilots license, because the craft will fly itself.

The bad news is that it is at least 10 years away from being on sale (8:30)

AeroMobil looks more like a small airplane, than a helicopter with a fixed propeller tail, it also has two fold out wings, instead of the helicopter propellers used by TSX.

According to its developers, the AeroMobil might be available as early soon as 2017 for only a couple hundred thousand dollars.

Both of these options are essentially very small planes or helicopters that have been designed to also drive on roads and look kinds of like a car while doing it. Both ave ground speeds of approximately 160 km per hour and flight speeds of approximately 200 km per hour. And they can fly as far as 600-700 km.

So they are not quite cars with levitating propulsion jets like you see in Back to the Future, but it's a start. Overall I think we did pretty well, if you look back through history scientific progress is almost always asymmetrical. 

there are big breakthroughs like the microchip, microscope, or even the printing press, if you wanna go really far back, that open up new possibilities for little breakthroughs. Some fields benefit from breakthrough more than others, and this is the case for the microchip making computer-based technology zoom ahead.

So what is the next big breakthrough going to be? I don't know, but it's going to be cool to find out if the world changes as much in the next 26 years as it has since 1989.

(9:38)

Thank you for watching the show, now if you're wondering why we did not talk about hover boards it's because we have a whole episode of hover boards just talk about hover boards, so click on that if you want to watch that.

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