Untitled Document
Not a member yet? Register for full benefits!

Quotations Database

Book Quotes: Form Without Presence

Search Quotes

Search in this book only

Source: Arthur C Clarke, Profiles of the Future, Page: 190

"If you think that an immobile brain would lead a very dull sort of life, you have not fully understood what has already been said about the senses. A brain connected by wire or radio links to suitable organs could participate in any conceivable experience, real or imaginary. When you touch something, are you really aware that your brain is not at your fingertips, but three feet away? And would you notice the difference if that three feet were three thousand miles? Radio waves make such a journey more swiftly than the nervous impulses can travel along your arm."

Our Thoughts on this Quote

The above statement is simple, and yet profound. There is no set speed for how fast nerve impulses travel throughout the body. The speed varies from around two metres per second for unmyelinated nerves, who travel in short hops then pass to another in baton style transmissions, to the nerves which control the arms and legs. These are single nerves, two metres in length, their bodies encased in myelin sheaths to protect them and speed signal propagation. These reach a whopping 200 metres per second in propagation speed, and are the fastest signal propagators in the body.

If we then take the 200m/s as the body's upper speed limit, it takes just 1/200th of a second for the signal to travel from your pinkie, to your brain. What Arthur C Clarke is proposing above, is that that 1/200th of a second is enough time, if transmitted over a far faster medium, for you to control an external piece of equipment as if it was your own body part, and not know the difference.

The speed of light is 299,792,458 metres per second. In 1/200th of a second, a signal travelling down an optic fibre could travel 1,498,962.29 metres, or 1,499 kilometres in the same time it takes for that signal to travel from your pinkie to your brain. What is desired, is a way of connecting the two systems: The organic nervous system, and a fibre optic internet.

The range would decrease slightly due to fractions of a second taken to decipher and re-encode neural signals for transmission. Coming back the other way, they would need to be de-encoded and converted back into analogue nerve signals. Either way would take time, and shave off some of the maximum distance possible.

However, there is no reason to believe that this is not possible. In fact, this is what brain-machine interfaces do all the time, although admittedly the signal re-encoding is currently on the order of five to ten seconds, not 1/500th of a second or less. However, this is primarily because current methods do not interface all too well, and well, we have no idea still what most of the signals mean, so we have to translate, pattern match and, frankly, guess much of the time. This slows things down tremendously. As our abilities advance, this interpretation time will drop swiftly because we will be spending less and less time trying to decipher signals, and more time just switching transistor states as the signals come in.

Eventually we will reach the point where the bottleneck is not the interface, but the transmission speed of the nerves within the brain itself, and interfaces could conceivably become ever more invasive, in order to permit less and less travel by slow neuron axons. However, that is beyond the point being made here.

Once it is possible to seamlessly transfer from organic to artificial propagation means no slower than the natural nervous system works, will it actually be possible to move an arm across the room, feeling all the data it sends back, as if it were your own arm? The answer of course, is, yes, absolutely. Providing the signals propagate swiftly enough, and are decoded back into the nerve stream as natural signals should be, then there is no way that your brain would be able to think of that arm, or indeed that whole waldo body, complete in every detail, as anything other than itself. Rubber body illusion taken to the extreme.

Note: It should be pointed out that the propagation speeds enabled by our current understanding of maximum speed limit for information propagation, is the speed of light. The current maximum speed of light is the natural one, at travel 1,498,962.29 metres per second. It is the current limit, not an absolute one, because physicists have already managed to slow light down to just 300 metres per second, and, in unstable experiments, pushed it beyond its natural limitations.

We also have experiments in entangled particles for data transmission being carried out, with the hope to bypass the speed of light entirely. However, at the current stage, these are not far enough along to base conjecture upon their impact.

So it may be that at some point in the future, 1,400 km is not the maximum theoretical distance limit. However, for the foreseeable future, controlling a waldo body halfway around the world, and having it feel completely natural, is not going to be possible. At best, it would feel very sluggish, and probably disturbing thusly.

For the foreseeable, such use of propagation signals to create avatar forms in cyberspace, will be limited by physical proximity to the world server.

Diagram Explanation of the Steps Involved

Related Articles
No resources have yet been matched to this quote.


Search Quotes

About the Book 'Profiles of the Future: An Inquiry into the Limits of the Possible'
By Arthur C Clarke
Produced By Phoenix

This book was originally produced in 1962, heralding Arthur?s predictions of the future of mankind, from a technological standpoint, across all sectors of industry and life. It was based on his own essays, written during the period 1959 - 1961.

Since it was concerned with ultimate possibilities, and not with achievements to be expected in the near future, even the post 2000 technological acceleration has dented many of the predictions within it. However, the author went over the book in the early 2000s, editing most of the chapters, and explaining where his predictions went wron...
Click here for full review of Profiles of the Future: An Inquiry into the Limits of the Possible

No other VR books by this author on file



Similar Quotes