Will the future quantum computers use the binary (base 2), the ternary (base 3) or the quaternary (base 4) numeral system?

• September 8th, 2014, 10:19 AM
Will the future quantum computers use the binary (base 2), the ternary (base 3) or the quaternary (base 4) numeral system?
Hello.

Our current computers use bits, so they use the binary numeral system. But I heard that the future quantum computers will use qubits instead of simple bits.

Since in the word "qubit" there is the word "bi" I first thought that this meant that quantum computers would use binary (base 2).

But then I heard that qubits had three possible states: 0, 1, or a superposition of 0 and 1. So I then thought that this must mean that they will use ternary (base 3).

But then I saw that one qubit can hold as much information as two bits. So I thought that this maybe mean that they will use quaternary (base 4).

So which numeral system will the future quantum computers use: binary, ternary or quaternary?

• September 8th, 2014, 12:44 PM
MagiMaster
They're still binary. A superposition is not a 2 or a 3. It's both a 0 and a 1. The thing about qubits is that they can be somewhere between 0 and 1, but when you go to measure them you don't get 0.2324..., you get 0 or 1 with some probability. When you throw entanglement in to that, you can do some potentially interesting things with that detail.

Now, I haven't heard anything about a qubit holding two bits of information and without a reference I don't know what they mean.
• September 10th, 2014, 05:31 PM
Quote:

Originally Posted by MagiMaster
They're still binary. A superposition is not a 2 or a 3. It's both a 0 and a 1. The thing about qubits is that they can be somewhere between 0 and 1, but when you go to measure them you don't get 0.2324..., you get 0 or 1 with some probability. When you throw entanglement in to that, you can do some potentially interesting things with that detail.

Now, I haven't heard anything about a qubit holding two bits of information and without a reference I don't know what they mean.

I've found that information on the Wikipedia article "Superdense coding" (sorry I can't post the link for some reason).

Quote:

Suppose Alice would like to send classical information to Bob using qubits, instead of classical bits. Alice would encode the classical information in a qubit and send it to Bob. After receiving the qubit, Bob recovers the classical information via measurement. The question is: how much classical information can be transmitted per qubit? Since non-orthogonal quantum states cannot be distinguished reliably, one would guess that Alice can do no better than one classical bit per qubit. Holevo's theorem discusses this bound on efficiency. Thus there is no advantage gained in using qubits instead of classical bits. However, with the additional assumption that Alice and Bob share an entangled state, two classical bits per qubit can be achieved. The term superdense refers to this doubling of efficiency. Also, it can be proved that the maximum amount of classical information that can be sent (even while using entangled state) using one qubit is 2 bits.
• September 10th, 2014, 05:44 PM
MagiMaster
That contradicts the information from the Holevo's theorem article (Holevo's theorem - Wikipedia, the free encyclopedia) which says you can only recover n bits of information from n qubits. It also says that's only an upper bound, which means we know it can't be higher, but it might be lower. I don't know enough about quantum information theory to say which is more accurate.

BTW, you can't post links until your post count goes up a bit. It's an anti-spam measure.
• September 13th, 2014, 05:59 PM
Scott Mayers
I'm doubtful at this point a quantum computer can be realized through quantum mechanical means as they intend. However, regarding the Radix's OP, I think that the we will be able to approach this through things like we are at present with multi-varied units as in the USB technology. They use variable storable charges to model this so that it can handle more information per unit of memory. Normal capacitors (as in our RAM dynamic memories), lose their charge because you cannot keep the charge from draining and has to be constantly re-charged as the computer is on. The USB tech combines the charge capacity within the transistors and can hold it for very long periods. They can also hold various distinct charges. The only trouble with this is that to fetch the data, it goes into computer memory serially (to RAM) and so gets expanded to binary. The reason they can't use this directly is because of the write/rewrite processes are slowed down and will eventually break down with repeated use at present.
• September 13th, 2014, 08:23 PM
Daecon
Is quantum computers can use superpositions, is the idea of a "fractal base" nonsensical?
• September 13th, 2014, 09:07 PM
MagiMaster
Quote:

Originally Posted by Daecon
Is quantum computers can use superpositions, is the idea of a "fractal base" nonsensical?

Yes, that doesn't make any sense.

Quote:

Originally Posted by Scott Mayers
I'm doubtful at this point a quantum computer can be realized through quantum mechanical means as they intend. However, regarding the Radix's OP, I think that the we will be able to approach this through things like we are at present with multi-varied units as in the USB technology. They use variable storable charges to model this so that it can handle more information per unit of memory. Normal capacitors (as in our RAM dynamic memories), lose their charge because you cannot keep the charge from draining and has to be constantly re-charged as the computer is on. The USB tech combines the charge capacity within the transistors and can hold it for very long periods. They can also hold various distinct charges. The only trouble with this is that to fetch the data, it goes into computer memory serially (to RAM) and so gets expanded to binary. The reason they can't use this directly is because of the write/rewrite processes are slowed down and will eventually break down with repeated use at present.

But neither does this. A quantum superposition is something fundamentally different from either an analog signal (like a capacitor) or a multibit digital signal (such as accessing memory in parallel). Also, the order of access has nothing to do with the analog-to-digital conversion.
• September 15th, 2014, 01:57 AM
Scott Mayers
Quote:

Originally Posted by MagiMaster

Quote:

Originally Posted by Scott Mayers
I'm doubtful at this point a quantum computer can be realized through quantum mechanical means as they intend. However, regarding the Radix's OP, I think that the we will be able to approach this through things like we are at present with multi-varied units as in the USB technology. They use variable storable charges to model this so that it can handle more information per unit of memory. Normal capacitors (as in our RAM dynamic memories), lose their charge because you cannot keep the charge from draining and has to be constantly re-charged as the computer is on. The USB tech combines the charge capacity within the transistors and can hold it for very long periods. They can also hold various distinct charges. The only trouble with this is that to fetch the data, it goes into computer memory serially (to RAM) and so gets expanded to binary. The reason they can't use this directly is because of the write/rewrite processes are slowed down and will eventually break down with repeated use at present.

But neither does this. A quantum superposition is something fundamentally different from either an analog signal (like a capacitor) or a multibit digital signal (such as accessing memory in parallel). Also, the order of access has nothing to do with the analog-to-digital conversion.

I recognize quantum superposition is a type of 'contradictory' logic such that more than one thing can be true and false of the same thing (or ? other?). I was just showing how we might deal with this in practice. As for my doubt, this only concerns my contemporary understanding of the interpretation of quantum mechanics. At present, I still do not see this as possible only because I see an interpretation of it in which it is still in non-contradictory. This is only my view and something of which I still need to do more homework and, if I can, prove otherwise. [I see the apparent contradictory nature of light to be both a wave and a particle as non-contradictory. But this 'contradictory' nature is what is being used to interpret the possibility of a 'quantum' logic.
• September 15th, 2014, 04:04 AM
MagiMaster
I'm pretty sure you're not using the standard definition of contradictory. Besides that, no interpretation matters. All that matters is whether or not it works, and every test says it does. Actually building a quantum computer is "only" a matter of engineering.

As to the "contradictory" nature of a qubit, it's not helpful to think of it as being both true and false. Instead think of it as being both 1 and 0. Except that's still an oversimplification. A qubit behaves in a very well-defined way such that it can be given a probability of being a 1 or a 0 when measured. By itself this gives us a handy source of true randomness, but no real power. The interesting thing is when you put several together and they are made to effect each other. Then you can alter the probabilities such that 10 and 01 is much more likely than 00 or 11 (as a simple example). With this, you can start to do a few things that aren't practical on ordinary computers.
• September 15th, 2014, 05:06 AM
Scott Mayers
Quote:

Originally Posted by MagiMaster
I'm pretty sure you're not using the standard definition of contradictory. Besides that, no interpretation matters. All that matters is whether or not it works, and every test says it does. Actually building a quantum computer is "only" a matter of engineering.

As to the "contradictory" nature of a qubit, it's not helpful to think of it as being both true and false. Instead think of it as being both 1 and 0. Except that's still an oversimplification. A qubit behaves in a very well-defined way such that it can be given a probability of being a 1 or a 0 when measured. By itself this gives us a handy source of true randomness, but no real power. The interesting thing is when you put several together and they are made to effect each other. Then you can alter the probabilities such that 10 and 01 is much more likely than 00 or 11 (as a simple example). With this, you can start to do a few things that aren't practical on ordinary computers.

I'm a little confused at how this is being done practically as the only references I've learned so far is only the statements on popular media for this. I haven't witnessed any actual description of 'how' whatever quantum thinking devices operate and only 'that' they do for some limited practice or experimentation. I'm familiar with some sufficient electronics involving computer engineering and do not know precisely what is being used at present to the supposed practical results of any quantum logic machine.

As for superposition, I see this as non-contradictory because I see it as being something other than is being presented in a contradictory way at present. It is assumed that superposition represents the fact that light appears as both a particle and a wave as if these are contradictory realities that they are not. The measure of something at a point may indicate what another point might be in potential opposition due to the same phenomena but this doesn't mean that if you can alter one of these, that it will certainly affect the other in the same way. It is assumed that since something can be measured at one point in space AND it indicates a perfect opposition within another point in space, that this is proof that somehow something contradictory actually affects two different points in space simultaneously. This is only due to a lack of imagination of the model and the logic involved that represents reality of the physics.

For instance, if something 'causes' a measure from some point that give us an 'A' and we also find a '-A' elsewhere else simultaneously, this might only indicate that the material nature of what we observe is a result of a binary function or cause from some origin ('O') between the two symmetrically in which the two apparently contradictory realities come from the same source. What seems to be assumed is that the 'A' that gets discovered is actually a 'point' reality of a particle in which, where one discovers a '-A' elsewhere, it is assumed that this is caused from the source, 'A', rather than something in between (the 'O').

The error seems to be in assuming that particles of matter represent 'point-like' entities. Instead, when the human imagination tries to think of some one exact thing as being in multiple places at once, they seem to forget that the measuer of reality can actually be only a measure of a result of an action (not a fixed 'thing') that occurred in between.

We shouldn't assume that if a contradictory appearance 'works' that we can assume this as actually being 'contradictory' in nature. Otherwise, we reduce our reasoning to assume that other contradictions have just as equal validity. I don't assume that such natures of contradiction do not appear to be the case at first. But we have to redress them to assure why and how they are NOT.

Any information on the 'engineering' would be highly welcoming as I have yet actually learned of this in practice.
• September 15th, 2014, 01:34 PM
MagiMaster
From your descriptions of quantum processes, it seems like you're taking the pop-sci explanations of these things as if it were the state of the art. Go out and read more. Maybe start with the Wikipedia articles on the qubit (Qubit - Wikipedia, the free encyclopedia) and then maybe look up some of the references on Google Scholar.
• October 2nd, 2014, 03:19 AM
Sealeaf
Quote:

Since in the word "qubit" there is the word "bi" I first thought that this meant that quantum computers would use binary (base 2).

I think the proper name for this type of reasoning is "Magical thinking". It happens to be true that quantum computers will use bianary but it is not because there is "bi" in the word "qubit". This come s under the " even a broken clock is right twice a day" rule.