[Cryptography] Quantum computers and the Government

[jrzx]

> > > We're finally reaching the feature size where quantum
> > >
> > > effects like 'quantum dots' can become ubiquitous.

> > Hardware capable of building a quantum computer using this approach
> > would capable of doing classical logic in a classical computer immensely
> > faster and at immensely lower power than anything we can build today.
>
> > Maybe it will be feasible to do that sort of thing in the distant future,
> > but if people had anything remotely approaching that kind of capability,
> > we would see it in a fundamental and radical transformation of classical
> > computers.

> Re: "a fundamental and radical transformation of classical computers"
>
> That's precisely what I'm saying, and we're a lot closer to this
> possibility than most people realize:
>
> https://en.wikipedia.org/wiki/Quantum_dot

No we are not.  Speed of logic circuits and power consumption per logic
state change has stopped following Moore's law.  Which is why the cooling
fans and heat sinks in your desktop computer have been getting bigger
and bigger.

A gate of this type capable of being used to build a quantum computer could,
vastly more easily and cheaply, be used to build a classical computer with a
clock frequency of five hundred terahertz, and an energy consumption
consumption of 1.0E-20 joules per state change per gate.

This is many, many, many, many iterations of Moore's law away, and we have
stopped following Moore's law for this.

That is around one hundred thousand times times faster and one hundred
thousandth the energy of current logic devices.

Moore's law for clock speed and energy consumption, which we are no longer
following, is that speed increases and energy consumption per state switch
decreases by around twenty percent a year.

So, if we were still following Moore's law, conventional logic devices
capable of implementing quantum computers would be sixty years away.