
Yale researchers 'teleport' a quantum gate - vtomole
https://news.yale.edu/2018/09/05/yale-researchers-teleport-quantum-gate
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nbourbaki
The article mentions that quantum computers are “an order of magnitude” faster
than traditional computing. My understanding is that at the moment, this is
incorrect: (noise-free) quantum computers are better at certain specific
tasks, and otherwise, are no better than classical computers.

~~~
etatoby
The "order of magnitude" statement is completely false.

If we're talking about algorithmic complexity: for some algorithms quantum
computers won't be any better than classical ones; for others, the improvement
will be exponential, not multiplicative, say from O(eⁿ) to O(n).

If we're talking about actual performance, we have no idea, because there is
no general purpose quantum computer yet.

So the mention of "orders of magnitude" belies a complete ignorance of the
topic.

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tstrass
Just FYI you're misusing "belies". You use it like "reveals" but it's meaning
is closer to the opposite, more like "misrepresents" or "contradicts".

~~~
etatoby
Ooops. Thanks

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tuananh
can anyone ELI5 what's the impact of this research?

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vtomole
Quantum computers are difficult to scale because of noise. Applying a quantum
gate to a qubit using teleportation is a protocol for performing fault-
tolerant quantum computation.

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hellweaver666
I don't know what 5 year olds you hang out with, but I think this would have
gone over their heads ;)

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scandox
On Hacker News everybody's five year old kids:

1\. Configure and run their own Minecraft Server

2\. Are fully proficient with the linux commandline

3\. Are skilled in basic safe cracking techniques such as auto-dialling, weak
point drilling, scoping and the use of brute force methodologies including the
use of thermal lances (having acquired relevant Health and Safety
accreditations).

~~~
jacquesm
And besides that they are on their third startup, have a blog, will debate the
finer points of faking it until you make it with gusto, and are proficient in
LISP, Rust and Elixir.

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rikkus
And will explain monads to their parents

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jacobush
Which is why we got them in the first place! Failure to contain I mean.

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jhabdas
So did any of these five year olds notice this sentence?

> Using a theoretical protocol developed in the 1990s, Yale researchers
> experimentally demonstrated a quantum operation, or “gate,” without relying
> on any direct interaction.

They're basically saying it's magic. But no 5 year olds I hang out with are
any good at magic yet.

~~~
vtomole
Quantum teleportation is the transmission of a quantum state using an
entangled pair and two classical bits. No magic needed.

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etatoby
I'm looking forward to the first quantum computer with hundreds or thousands
of qubits, to see how the Many Worlds deniers explain its existence.

~~~
pure-awesome
(Disclaimer: I am not a physicist)

Probably they would just explain it with the normal Copenhagen interpretation?

[https://en.wikipedia.org/wiki/Copenhagen_interpretation](https://en.wikipedia.org/wiki/Copenhagen_interpretation)

In terms of quantum theory, the behaviour of a quantum computer is not
fundamentally any different to the behaviour of any small scale particle or
collection of particles.

Even buckyballs have been shown to self-interfere in a double-slit experiment,
and that doesn't _prove_ multi-worlds over the Copenhagen interpretation.

[https://web.archive.org/web/20120331115055/http://www.quantu...](https://web.archive.org/web/20120331115055/http://www.quantum.at/research/molecule-
interferometry-foundations/wave-particle-duality-of-c60.html)

There might be other philosophical reasons to believe in many-worlds, and I am
partial to it myself, but experimental observation of this form would not to
my understanding contribute to that argument.

~~~
somethingroma
They've gotten it a little bit bigger than a buckyball

[https://arxiv.org/abs/1310.8343](https://arxiv.org/abs/1310.8343)

Also what's cool is that these things are visible under an electron microscope
(so are buckyballs iirc).

