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Comment by jahansafd | Hacker News Reader

how can we decrease the packet round trip from CA to Netherlands?

There's not much room for improvement. It's a little over 5000 miles from CA to the Netherlands, so light takes about 30ms to travel that far on a vacuum. That means a 60ms round trip minimum. Light in fiber goes at 0.6-0.7c, so the fastest round-trip you could have with a straight fiber line is 80ish milliseconds.

Figure out how to make "fiber" that transmits light closer to c, perhaps? This of course would bring other challenges- the refractive index is part of why light stays "inside" fiber in the first place.

You can use a line of microwave towers, taking us back to the mechanical semaphore telegraphs from before Morse.

The key to improve the noticeable latency is to improve our protocols to minimise the number of round trips; ie the packet latency is pretty much a physical quantity, but if we can reduce the number of times we incure it, we will improve our protocols.

Move CA or Netherlands.

They are moving - just not very fast and unfortunately (at least at the moment) in the wrong direction.

Short of tunneling through the earth or quantum entanglement, nothing much.

Or neutrinos through the Earth.

Interesting idea. We have the ability to detect neutrinos. Do we have any easy ways to produce and aim them in the right direction?

Edit: seems like they can be produced with a high-intensity laser http://iopscience.iop.org/0954-3899/28/6/324/

Take a look at the CERN Neutrinos to Gran Sasso (CNGS) neutrino beam experiments. They start with a proton beam at CERN. Aim it at a carbon target. The results produces pions and kaons, which decay into muons and neutrinos. The beamline, and hence the neutrinos, was directed towards Italy.

In the experiment, they can generate pulses of 3 nanoseconds, each with up to 524 nanosecond gaps. This gives a 2MHz signal. However, not all of those pulses were detected.

If I read this right, "We report here on results based on part of the data taken during 2008 and 2009 runs, which amounted respectively to 1.78 and 3.52 × 1019 [protons on target], respectively. Among the 10122 and 21428 on-time events taken in 2008 and 2009, respectively 1698 and 3693 events were identified as candidate neutrino interactions in the target bricks."

Elsewhere, I found that the experiment ran from 27 May - 23 Nov 2009. I don't know if the beam was in continuous use for all 6 months. Let's assume it was full-time for only 1 month of that, which is unlikely.

There's a signal of some 3000 events per month, giving a transmission rate of 100 bits per day, or about 1 bit every 15 minutes. Rather a lot lower than 2MHz.

We would need some way which is about at least 1,000,000x better at detecting neutrinos before some company is willing to fund the Sydney/Wall St. neutrino beamline.

I thought quantum entanglement was incapable of transmitting information, for reasons beyond my basic undergrad comprehension of quantum mechanics.

Recent discussion with a bit more details: http://news.ycombinator.com/item?id=4949355

My (ever-so-slightly more than basic undergrad) understanding is that you could send qubits to the Netherlands, have processing be performed by a quantum computer there, and have the result returned faster-than-light (as qubits), but no-one in the Netherlands could read your data or the result (or even the power meter) before at least a light-speed delay.

(If I'm wrong please correct me!)

Short of quantum entanglement... not much.

Shrinking the earth might actually be more feasible than that, though.

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