[TML] A little tinkering with Lasers

[shadow at shadowgard.com]

On 24 Aug 2007 at 13:48, Glenn M. Goffin wrote:

> >From: shadow at shadowgard.com
> 
> On 23 Aug 2007 at 9:46, Glenn M. Goffin wrote:
> 
> >> Meson communicators don't have much impact on communications >>in
> a star system.  Theoretically you could talk to a ship on the other
> >> side of a planet, but you have to know exactly where it is, so you
> >> need some kind of sensor link, so you might as well use laser or
> >> maser comm through the link.  You have the same time lag as laser
> >> or radio.
> 
> >Uh, no. The lag time is a lot lower because the radio/laser link has
> 
> >to go "around" the planet (likely adding 50 to 100 percent to the
> lag
> >time) while the mesons take the straight line path.
> 
> The time it takes light to go, say, 10,000 km is essentially zero. 
> 100% of essentially zero is still essentially zero, and two times
> essentially zero is essentially zero.

Actually it's *not* essentially zero. Otherwise you wouldn't notice 
the lag time on a satellite link compared with a cable across the 
seafloor.

Don't forget that the lower the orbit the two ships are in, the 
*farther* out a relay has to be to be able to see both of them.

> I wasn't talking about time lag in the context of orbital
> communications.  I was talking about the time lag in intrasystem
> communications.  Messages from a meson communicator take just as long
> to travel from, for example, one planet to another, as messages from
> a laser communicator.  I was referring to that sameness of time lag.

I was responding to the *specific* situation mentioned of using meson 
comms between two ship on oppodsite sides of a planet versus EM comms 
thru a relay "past" the planet.

--
Leonard Erickson (aka shadow)
shadow at shadowgard dot com