Post Proscriptions: Learning electricity

Expert snuggler wrote:The TF had compact fusion plants. What if the Gbaba were tracking neutrino emissions? No matter how well you shield your electrical equipment, it would require theoretical breakthroughs to shield neutrinos.

They'd have to detect it against the background noise of a nearby star, though.

Interestingly enough, the proposed reactions for artificial fusion power don't actually produce neutrinos, so you might not have to worry about this after all.

In fusion, a neutrino is only produced when a proton is transmuted into a neutron (or vice-versa, with all signs reversed) - since charge must be conserved, a positron is emitted, but since lepton number must be conserved you have to also get an neutrino to balance the anti-electron (aka positron). The reason this is relevant is that this depends on the *weak* nuclear force (it's actually a type of radioactive decay), and is thus a very unlikely event.

For example, in stars like the Sun the first step of the proton-proton chain is commonly described as "1 proton + 1 proton -> 1 deuterium + 1 positron + 1 neutrino", where one of the protons has become a neutron in the deuterium nucleus. What this overlooks is that, since it requires the unlikely conversion of a proton into a neutron, most of the time when two protons fuse they just fall right back apart again into two protons and only rarely do you actually get a deuterium nucleus out.

Thus, the first step of the proton-proton chain (and any other reaction requiring this sort of conversion) is actually extremely slow, which is not what you want for artificial fusion. Stars can get away with it because they're enormous, but a fusion reactor needs much faster reactions to actually produce any useful power. Thus you get proposed fusion reactions like D+D -> T+p/3He+n or D+3He -> 4He+p, which do not require the transmutation of protons into neutrons (or vice-versa) and therefore do not emit neutrinos. It's plausible that you might get a few neutrinos in some cases through very rare side reactions, but they're not the main output.

Expert snuggler wrote:Radio is the first thing that comes to 21st-century minds, but it's a great point that it might have been something else.

Not so much "radio" as "light speed" because we don't know of anything that propagates faster. Whatever emissions the Gbaba detected are going to take a couple of centuries to reach the old Terran Federation and/or the Gbaba.

Also, "Radio," aka anything in the electromagnetic spectrum, is going to be a side-effect of experimentation with basic electricity -- mostly a problem for potentially waking the OBS rather than the Gbaba whether the Proscriptions are overturned or not.

Disabling the OBS is a prerequisite for overturning the Proscriptions, so presumably not a problem for the main topic.

Weird Harold wrote:

Expert snuggler wrote:Radio is the first thing that comes to 21st-century minds, but it's a great point that it might have been something else.

Not so much "radio" as "light speed" because we don't know of anything that propagates faster. Whatever emissions the Gbaba detected are going to take a couple of centuries to reach the old Terran Federation and/or the Gbaba.

Also, "Radio," aka anything in the electromagnetic spectrum, is going to be a side-effect of experimentation with basic electricity -- mostly a problem for potentially waking the OBS rather than the Gbaba whether the Proscriptions are overturned or not.

Disabling the OBS is a prerequisite for overturning the Proscriptions, so presumably not a problem for the main topic.

Given that Safehold is thousands of light years away from where Operation Arc began its journey, there is really no concern that the Gbaba will detect them unless they are in the actual area looking. That possibility was why it was necessary to go bush those first 500 or so years. Now at a thousand years out, the danger threshold has dropped to the point where it would be safe to start using such things as radio and electricity.

Given that Operation Arc traveled thousands of light years in 10 years, it is obvious that their travel in hyper was ftl. The possibility of a ftl signal reaching the Gbaba would be much greater, suggesting that ftl emissions should be avoided until such a time as humanity is prepared to deal with the risk they present.

Don

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n7axw wrote:Given that Operation Arc traveled thousands of light years in 10 years, it is obvious that their travel in hyper was ftl. The possibility of a ftl signal reaching the Gbaba would be much greater, suggesting that ftl emissions should be avoided until such a time as humanity is prepared to deal with the risk they present.

"FTL travel" does not necessarily equate to "FTL emissions" The Honorverse is a good example; FTL "emissions" are from Impeller drives (and more recently grav-pulse communications) and relatively short ranged. Essentially nothing FTL is detectable in the Honorverse beyond a couple of light hours. Terran Federation Tech FTL drives are probably no more detectable than Honorverse drives/comms.

??I have a vague memory that the TF had no FTL communications except via couriers -- no equivalent of subspace radio.

If there were something that radiated FTL they would definitely have harnessed it for communication.

Expert snuggler wrote:??I have a vague memory that the TF had no FTL communications except via couriers -- no equivalent of subspace radio.

If there were something that radiated FTL they would definitely have harnessed it for communication.

Crestwell's World didn't have a hypercom, but that was probably because it was a new colony. The other colonies did have one (OAR, I think); presumably, that's how they heard back from the earlier hidden colony when they were attacked.

Weird Harold wrote:

n7axw wrote:Given that Operation Arc traveled thousands of light years in 10 years, it is obvious that their travel in hyper was ftl. The possibility of a ftl signal reaching the Gbaba would be much greater, suggesting that ftl emissions should be avoided until such a time as humanity is prepared to deal with the risk they present.

"FTL travel" does not necessarily equate to "FTL emissions" The Honorverse is a good example; FTL "emissions" are from Impeller drives (and more recently grav-pulse communications) and relatively short ranged. Essentially nothing FTL is detectable in the Honorverse beyond a couple of light hours. Terran Federation Tech FTL drives are probably no more detectable than Honorverse drives/comms.

You are right, of course... with qualification. The Honorverse is not Safehold. FTL and hyper are handwavium catergories that vary in both possibility and definition from author to author and universe to universe. In fact David has not been consistent. You are right that there is no hypercom in Honorverse. However in Duhak you have both hypercom and transmat.

However in the Safehold universe I really don't have anything concrete to establish hypercom.

But the question is how that colony fleet that was destroyed prior to Operation Ark located by the Gbaba. According to textev in OAR, the governor of the colony believed that they had been found through the betraying emissions of TF tech. How far out were they? Normal light speed emissions or ftl?

So although I can't really establish my point here, I'll admit that the questions aren't quite settled in my mind.

Don

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Weird Harold wrote:

n7axw wrote:
"FTL travel" does not necessarily equate to "FTL emissions" The Honorverse is a good example; FTL "emissions" are from Impeller drives (and more recently grav-pulse communications) and relatively short ranged. Essentially nothing FTL is detectable in the Honorverse beyond a couple of light hours. Terran Federation Tech FTL drives are probably no more detectable than Honorverse drives/comms.

You are right, of course... with qualification. The Honorverse is not Safehold. FTL and hyper are handwavium catergories that vary in both possibility and definition from author to author and universe to universe. In fact David has not been consistent. You are right that there is no hypercom in Honorverse. However in Duhak you have both hypercom and transmat.

However in the Safehold universe I really don't have anything concrete to establish hypercom.

But the question is how that colony fleet that was destroyed prior to Operation Ark located by the Gbaba. According to textev in OAR, the governor of the colony believed that they had been found through the betraying emissions of TF tech. How far out were they? Normal light speed emissions or ftl?

So although I can't really establish my point here, I'll admit that the questions aren't quite settled in my mind.

Don

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I'm gonna correct my own post here. The Safehold universe does have hypercom, mentioned right there in OAR as a part of the discussion of Operation Ark at the beginning of the book.

And thus they would have ftl communication.

Don

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n7axw wrote:I'm gonna correct my own post here. The Safehold universe does have hypercom, mentioned right there in OAR as a part of the discussion of Operation Ark at the beginning of the book.

And thus they would have ftl communication.

Don

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There's also mention of getting a hypercomm message from the FIRST attempt at creating a Safehold-type colony because they had been discovered by the Gbaba. One of the justifications for Safehold primitivism is to avoid any betraying emissions that gave the first colony away.

That said, TF hypercomms must be massive facilities if only planets and not ships can have them. OTOH, they're for communications between worlds many lightyears apart, so it doesn't rule out the possibility of ships creating FTL transmissions that could be detectable over much shorter distances.

And if you have ships wandering around the local stellar neighborhood generating those emissions, you vastly increase your chances of being detected over a single unmoving planet making those emissions.

evilauthor wrote:

n7axw wrote:I'm gonna correct my own post here. The Safehold universe does have hypercom, mentioned right there in OAR as a part of the discussion of Operation Ark at the beginning of the book.

And thus they would have ftl communication.

Don

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There's also mention of getting a hypercomm message from the FIRST attempt at creating a Safehold-type colony because they had been discovered by the Gbaba. One of the justifications for Safehold primitivism is to avoid any betraying emissions that gave the first colony away.

That said, TF hypercomms must be massive facilities if only planets and not ships can have them. OTOH, they're for communications between worlds many lightyears apart, so it doesn't rule out the possibility of ships creating FTL transmissions that could be detectable over much shorter distances.

And if you have ships wandering around the local stellar neighborhood generating those emissions, you vastly increase your chances of being detected over a single unmoving planet making those emissions.

Exactly...which was the point of my original post on the subject.

Don

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