When is 128bit computing coming?

[ShintaiDK]

Quantum computing really blows my mind. I understand hardly anything about it, although that might be because they still don't exist.

http://www.dwavesys.com/d-wave-two-system

 

[Morbus]

Remember how the NES was 8-bit and the SNES was 16-bit? More is better!

My GTX760 is 256bit...

 

[witeken]

As far as I know, that isn't a real QC, sort of like how TSMC's 16nm isn't a real 16nm node.

 

[Exophase]

I guess we'll need quantum computers for such massive amounts of memory. Then you need just 128 quantum bits to have 2^128 bits of memory (correct me if I'm wrong).

It doesn't work like that: when you measure the qubits it collapses to a classical state, it can't work as memory. Consequently, you also can't copy a superposition of qubits (no-cloning theorem)

The power of quantum computing is all in the operations you perform on the qubits before measuring the result.

 

[witeken]

From Wikipedia: "In general, a quantum computer with n qubits can be in an arbitrary superposition of up to 2^n different states simultaneously (this compares to a normal computer that can only be in one of these 2^n states at any one time)."

 

[BrightCandle]

From Wikipedia: "In general, a quantum computer with n qubits can be in an arbitrary superposition of up to 2^n different states simultaneously (this compares to a normal computer that can only be in one of these 2^n states at any one time)."

In the exact same way that a 128 bit Int in normal memory can hold on of 2^n possible states, the only difference between the quantum bit is in all of them to some probability model based on the calculation. A quantum computer with 128 qubits is more akin to a 128 bit register than it is 2^128 bits of memory.

 

[Exophase]

From Wikipedia: "In general, a quantum computer with n qubits can be in an arbitrary superposition of up to 2^n different states simultaneously (this compares to a normal computer that can only be in one of these 2^n states at any one time)."

In what way do you think what I said contradicts this? It doesn't matter how many states the qubits can be in, if you can't measure the state coefficients directly and can't copy the qubits you can't use it as memory. When you measure it it collapses to only one state and all that information is gone.

 

[witeken]

In what way do you think what I said contradicts this? It doesn't matter how many states the qubits can be in, if you can't measure the state coefficients directly and can't copy the qubits you can't use it as memory. When you measure it it collapses to only one state and all that information is gone.

Sorry, I didn't think the Wikipedia quote contradicted anything you said, I just referenced to the omniscient Wikipedia, and was too lazy to make any comment. I was thinking about that 2^128 thing when writing the first post about QC, but Wikipedia correctly tells me that I was wrong.

 

[TuxDave]

I guess we'll need quantum computers for such massive amounts of memory. Then you need just 128 quantum bits to have 2^128 bits of memory (correct me if I'm wrong).

Yeah you'll need something out of this world to handle 2^128 bits of memory. If process technology evolved such that 1 silicon atom = 1 bit of memory.

2^128 silicon atoms = 16 petagrams of silicon (I pray my chemistry knowledge is intact). That is on the order of the weight of Mt Everest at that point.

2^128 atoms / (6.022 * 10 ^ 23 atoms/mole) * 28 grams/mole of silicon.

 

[Gryz]

My GTX760 is 256bit...

That is the width of the data bus.
What we are talking about here is the length of registers in a CPU.