5 ms·

Or any form of electromagnetic wave passing media with low dielectric constant. Like microwave communication in athmosphere. Speed of propagation in typical ca

Or any form of electromagnetic wave passing media with low dielectric constant. Like microwave communication in athmosphere. Speed of propagation in typical cable is around 66% of c. That is not too bad. More latency is probably caused by buffering. Speed of light is just too low. We should get a lobby-group working on it and the limiting laws of physics.

fredley 9y ago
AFAIK (and I don't know much), c is also a huge limiting factor in processor design, since high-enough clock speeds put a hard cap on how far a signal can travel between ticks, even assuming perfect components. Agree that c is too low and we should attempt to simulate a universe in which it is higher and go live there instead.
- pjc50 9y ago
  (source: used to write chip design software) The timing calculation approximation we used had no term for 'c' in it at all. The simple approximation is just an RC timing curve: total capacitance of the wire and gates that you need to change, through the on-resistance of the driving FET. The more complex version treats each wire as a transmission line and incorporates its inductance, but ultimately for electrical signals travelling in a medium near a ground the important factor is the dielectric, not the speed of light. The other massive limiting factor in processor design is heat conduction.
the8472 9y ago
You really shouldn't be complaining about the speed of light. We're leaving a lot on the table by sending the data along the surface of earth instead of through it. With neutrino-based signalling you eliminate both the lower propagation speed and the suboptimal path.
- RangerScience 9y ago
  You should check out "spark gap radio". Basically, lightning causes ripples in the Earth's electromagnetic sphere. Those ripples travel across the surface of the earth at an apparent speed that's faster than light, because the actual path is through the earth.
- sgift 9y ago
  Has neutrino-based signalling been achieved or is it still a research topic? Last time I read about it it was more a case of "if we could do this it would be great, but we have no idea how to do it" and a quick Google search only brought a Forbes article from 2012 which had a similar sentiment.
  - the8472 9y ago
    The OPERA experiment (of false FTL neutrino discovery fame) did create and detect neutrino pulses as part of their experimental setup. It's possible as far as the physics go but also impractical given the particle accelerator and detectors needed. And the post-processing the scientists had to do to tease out the timing information also would negate any latency advantage.
  - dukwon 9y ago
    > Has neutrino-based signalling been achieved or is it still a research topic? An accelerator- or reactor-based neutrino experiment can detect whether the source is on or off, so in principle you can send binary information. This has been demonstrated using NuMI/MINERvA [1]. It's more of a novelty than anything practical. [1] https://arxiv.org/abs/1203.2847 https://arxiv.org/abs/1203.2847
- xaedes 9y ago
  Couldn't satellite distributed quantum entanglement also accomplish sending messages "through" the earth once properly set up? https://www.scientificamerican.com/article/china-shatters-ldquo-spooky-action-at-a-distance-rdquo-record-preps-for-quantum-internet/ https://www.scientificamerican.com/article/china-shatters-ld... http://spectrum.ieee.org/telecom/security/two-steps-closer-to-a-quantum-internet http://spectrum.ieee.org/telecom/security/two-steps-closer-t...
  - the8472 9y ago
    No, that is a common misconception. Quantum teleportation always requires a classical communication side-channel and thus is bounded by the same speed limitations as the classical link.

fredley 9y ago

AFAIK (and I don't know much), c is also a huge limiting factor in processor design, since high-enough clock speeds put a hard cap on how far a signal can travel between ticks, even assuming perfect components. Agree that c is too low and we should attempt to simulate a universe in which it is higher and go live there instead.

pjc50 9y ago
(source: used to write chip design software) The timing calculation approximation we used had no term for 'c' in it at all. The simple approximation is just an RC timing curve: total capacitance of the wire and gates that you need to change, through the on-resistance of the driving FET. The more complex version treats each wire as a transmission line and incorporates its inductance, but ultimately for electrical signals travelling in a medium near a ground the important factor is the dielectric, not the speed of light. The other massive limiting factor in processor design is heat conduction.

the8472 9y ago

You really shouldn't be complaining about the speed of light. We're leaving a lot on the table by sending the data along the surface of earth instead of through it. With neutrino-based signalling you eliminate both the lower propagation speed and the suboptimal path.

RangerScience 9y ago
You should check out "spark gap radio". Basically, lightning causes ripples in the Earth's electromagnetic sphere. Those ripples travel across the surface of the earth at an apparent speed that's faster than light, because the actual path is through the earth.
sgift 9y ago
Has neutrino-based signalling been achieved or is it still a research topic? Last time I read about it it was more a case of "if we could do this it would be great, but we have no idea how to do it" and a quick Google search only brought a Forbes article from 2012 which had a similar sentiment.
- the8472 9y ago
  The OPERA experiment (of false FTL neutrino discovery fame) did create and detect neutrino pulses as part of their experimental setup. It's possible as far as the physics go but also impractical given the particle accelerator and detectors needed. And the post-processing the scientists had to do to tease out the timing information also would negate any latency advantage.
- dukwon 9y ago
  > Has neutrino-based signalling been achieved or is it still a research topic? An accelerator- or reactor-based neutrino experiment can detect whether the source is on or off, so in principle you can send binary information. This has been demonstrated using NuMI/MINERvA [1]. It's more of a novelty than anything practical. [1] https://arxiv.org/abs/1203.2847 https://arxiv.org/abs/1203.2847
xaedes 9y ago
Couldn't satellite distributed quantum entanglement also accomplish sending messages "through" the earth once properly set up? https://www.scientificamerican.com/article/china-shatters-ldquo-spooky-action-at-a-distance-rdquo-record-preps-for-quantum-internet/ https://www.scientificamerican.com/article/china-shatters-ld... http://spectrum.ieee.org/telecom/security/two-steps-closer-to-a-quantum-internet http://spectrum.ieee.org/telecom/security/two-steps-closer-t...
- the8472 9y ago
  No, that is a common misconception. Quantum teleportation always requires a classical communication side-channel and thus is bounded by the same speed limitations as the classical link.