View Full Version : The Von Neumann's machine


Fausto Intilla
10-21-06, 12:41 PM
In 1950, Von Neumann, suggested that a car able to reproduce itself, of which the replication cycle resulted surprisingly similar to that of viruses. In The anthropic principle, Barrow and Tipler explain with the following words the functioning of a machine by Von Neumann:

“In Von Neumann’s scheme, a machine which reproduces itself consists in two parts, a constructor and an information deposit which contains the instructions for the constructor. The latest is a machine which manipulates the matter enough to be able to make the necessary various parts of the selfreproducing machine and assemble them in the final structure. The complexity of the constructor greatly depends on that of the selfreplicant machine and by the material available in the environment. The most general type of constructor, called a universal constructor, is a machine, or if you prefer, a robot, able to do anything as long as it is given the appropriate instructions.(...)
The deposit of information consists in the memory of a calculator which contains detailed instructions on how the constructor needs to manipulate the matter: first of all, it supplies the instructions to make a copy of a constructor without the deposit of information, or a constructor with an with an empty calculator memory. The deposit of information is therefore duplicated, that is it registers the information contained in the memory of the calculator. Finally, the deposit of information and the constructor are assembled, so that the create a copy of the original machine. The copy has all the original information, so it is therefore able to reproduce itself in the same environment”.

Now, someone could object about the fact that Von Neumann’s machine should be intended to be like a physical entity open towards the environment which surrounds it (even though it is able reproduce itself); and in fact he would have all reasons to do so. Von Neumann`s machine, as described by Barrow and Tipler, is certainly able to self reproduce but it is absolutely not able to power itself, which is an essential condition if we want to describe it as a physical entity open towards the environment which surrounds it. Such machine, to be able to produce others similar to it, must accomplish a task, which means that it must consume energy. It will therefore only be able to produce a limited number of machines, a number that will obviously be in relation to its own autonomy (that is on the length of its own batteries!). The machines that are therefore produced, will themselves be bound to the quantity of energy which they initially have at their disposal, destined to lower the more they actually produce others. Therefore, to be able to talk about a machine, similar in each and every way to a living system, that is a physical entity, open towards its surrounding environment and thus able to power itself and secondarily able to reproduce, it is necessary that the same is able to constantly extract energy from its surrounding environment ... without ever having to be serviced by man! It is on the basis of these principles, that we will be able to elaborate, in a future which is surely not too far away, some kind of machine… of a perpetual motion. To enable machines to self replicate themselves it will be anyhow necessary to wait a long time…a very long time.
The creation of such kind of machine, able to reflect some proper and real living systems, is not however impossible. A solution could be to ensure that they can be powered by the energy of the sun; unfortunately with the technology that is nowadays available, they would not be able to constantly store a sufficiently high quantity of such energy to be able to reproduce themselves. We will therefore have to wait a few hundred years, before such machines can be produced. Until mankind will not be able to design and produce in series, engines of total annihilation, the film Terminator will never have any prophesy in it. Believe me.

Even supposing that one day science could create such monsters, that is machines able to reproduce themselves, w can only hope that they would always operate and in any case for the wellbeing of mankind.

“Science, each inclined towards its own direction, has up to now not caused much harm; but one day, the merging of fragments of dissociated conscious will open up panoramas of reality so terrifying…that we will either go crazy for the revelation, or will run away from its mortal light, searching refuge in the peace and security of new dark centuries”.
H.P. Lovecraft


Fausto Intilla
www.oloscience.com

valich
10-24-06, 12:54 AM
The article consistently states, "or if you prefer, a robot." Before you consider a self-replicating machine without needing environmental input (First Law of Thermodynamics - conservation of energy), you need to consider a "self-sustaining machine" or "perpetual motion," i.e. in which an object continues to move indefinitely without being driven by an external source of energy. I suggest you review the history of this subject on Wikipedia at: http://en.wikipedia.org/wiki/Perpetual_motion