5 ms·

Can someone ELI5 the advantage of terahertz (or sub-) communications over the plethora of currently available alternatives? Is there any edge to switching a sig

by fb03 4y ago

Can someone ELI5 the advantage of terahertz (or sub-) communications over the plethora of currently available alternatives? Is there any edge to switching a signal to that high of a carrier frequency?

charlescarver 4y ago
More bandwidth! Also depending on frequency, you might be able to use the EM spectrum more efficiently (e.g., multiple narrow wavelength lasers).
- klabb3 4y ago
  People focus too much on bandwidth, but latency is more important. Bandwidth has increased exponentially, but the speed of light has stayed the same for more than 10 years now.
  - hulitu 4y ago
    > but the speed of light has stayed the same for more than 10 years now. Don't worry, i bet that in the next time we will read on HN about revolutionary methods to increase the speed of light, just like those articles about fusion, charging or batteries. /s
    - greenbit 4y ago
      The news about the breakthrough in FTL will reach Andromeda long before that patent clerk's quaint musings about bendy space ever will.
  - JumpCrisscross 4y ago
    > the speed of light has stayed the same for more than 10 years now Little practical communication is constrained by the speed of light.
  - greenbit 4y ago
    It's usually stated in meters per second, a somewhat dry, cognitively inaccessible number. Try flipping it around though .. 3.336 microseconds per kilometer People, software engineering types anyway, have a feel for what a microsecond is; a CPU can get a quite noticeable amount of work done in a microsecond - and it takes three and a third of those just to reach the coffee shop on the corner! Jump across a continent, and now you're talking latencies on par with early 1980s disk systems. That being said, there's not too much you can do about the latency, 3E8 is the law, so we may as well fiddle with bandwidth.
    - ztetranz 4y ago
      Sort of related. "We can't send email more than 500 miles" https://web.mit.edu/jemorris/humor/500-miles https://web.mit.edu/jemorris/humor/500-miles
BenjiWiebe 4y ago
Because it's as-yet unused. The more spectrum we can get useful things done with, the more room there is for all those useful things.

by fb03 4y ago

charlescarver 4y ago

More bandwidth! Also depending on frequency, you might be able to use the EM spectrum more efficiently (e.g., multiple narrow wavelength lasers).

klabb3 4y ago
People focus too much on bandwidth, but latency is more important. Bandwidth has increased exponentially, but the speed of light has stayed the same for more than 10 years now.
- hulitu 4y ago
  > but the speed of light has stayed the same for more than 10 years now. Don't worry, i bet that in the next time we will read on HN about revolutionary methods to increase the speed of light, just like those articles about fusion, charging or batteries. /s
  - greenbit 4y ago
    The news about the breakthrough in FTL will reach Andromeda long before that patent clerk's quaint musings about bendy space ever will.
- JumpCrisscross 4y ago
  > the speed of light has stayed the same for more than 10 years now Little practical communication is constrained by the speed of light.
- greenbit 4y ago
  It's usually stated in meters per second, a somewhat dry, cognitively inaccessible number. Try flipping it around though .. 3.336 microseconds per kilometer People, software engineering types anyway, have a feel for what a microsecond is; a CPU can get a quite noticeable amount of work done in a microsecond - and it takes three and a third of those just to reach the coffee shop on the corner! Jump across a continent, and now you're talking latencies on par with early 1980s disk systems. That being said, there's not too much you can do about the latency, 3E8 is the law, so we may as well fiddle with bandwidth.
  - ztetranz 4y ago
    Sort of related. "We can't send email more than 500 miles" https://web.mit.edu/jemorris/humor/500-miles https://web.mit.edu/jemorris/humor/500-miles

BenjiWiebe 4y ago

Because it's as-yet unused. The more spectrum we can get useful things done with, the more room there is for all those useful things.