Meson alternatives?

[sir_pudding]

Originally Posted by Brett

You'd have to slow the planet to synchronous rotation as well, and even so the pole thus provided would not be the north pole of the planet.

Why can't the magnetic poles be oriented that way?

[Agemegos]

Originally Posted by sir_pudding

Why can't the magnetic poles be oriented that way?

I doubt that a planet in synchronous rotation with a period of 1600 years would have a magnetic field — dynamo effects in the core wouldn't be strong enough.

As for a planet with sensible rotation, I suspect that the magnetic poles have to be somewhere near the true poles, and I'm pretty sure that the magnetic field can't move through the material of the planet fast enough to circle the equator once per day.

But I don't really understand the generation of the planetary magnetic field, and I could be wrong.

Even if I am, that doesn't produce what is described, a northern hemisphere that is permanently sunlit.

[sir_pudding]

Originally Posted by Brett

As for a planet with sensible rotation, I suspect that the magnetic poles have to be somewhere near the true poles, and I'm pretty sure that the magnetic field can't move through the material of the planet fast enough to circle the equator once per day.

Uranus' true poles are roughly in the plane of the ecliptic and it's magnetic poles are at some crazy angle from that (~60 degrees). Isn't this a possibility elsewhere?

It is definitely possible to have a "sideways" planet with poles parallel to the ecliptic. We have one in this solar system. Of course it goes from one pole facing the sun in half the year to the other in the other half. This Traveller planet isn't like that, obviously.

EDIT:

Even if I am, that doesn't produce what is described, a northern hemisphere that is permanently sunlit.

Maybe it's the geographic Northern hemisphere and local maps define "north" as the direction that the primary is in. So it is always summer in the "north" but the "north" isn't the same place throughout the year. :)

[Agemegos]

Originally Posted by sir_pudding

So we are talking about the true pole here?

I presume so, but mostly since I would expect to be warned of non-standard usages.

What about the geographic pole? That's totally arbitrary, right?

Not as I understand the term. The geographical poles are identical with the true or rotational poles.

Can't the inhabitants of the planet just say that "north" is towards the primary?

They might, I guess. But is Behind the Claw written by or addressed to an inhabitant of Dinom? Is the non-standard sense established anywhere?

In a reference book written in modern English, I expect "north" to mean north unless I'm told otherwise. A book of this sort is pretty useless if the meanings of words in it is indiscernible.

Uranus' true poles are roughly in the plane of the ecliptic and it's magnetic poles are at some crazy angle from that (~60 degrees). Isn't this a possibility elsewhere?

If it's observed, I guess it must be possible. Do Uranus' magnetic poles rotate witht eh planet, or maintain a constant orientation in space, or maintain a constant orientation to the Sun?

It is definitely possible to have a "sideways" planet with poles paralegal to the ecliptic. We have one in this solar system.

Sure, but such a planet definitely does not have a northern hemisphere, or any hemisphere, that is permanently sunlit. Which is what Behind the Claw claims for Dinom. That being my point.

[jeff_wilson]

Originally Posted by Brett

If it's observed, I guess it must be possible. Do Uranus' magnetic poles rotate witht eh planet, or maintain a constant orientation in space, or maintain a constant orientation to the Sun?

They rotate with the planet.

[Agemegos]

Originally Posted by jeff_wilson

They rotate with the planet.

Figures, I guess.

[Anaraxes]

Originally Posted by Anthony

Any effect that elongates the planet will similarly elongate the atmosphere.

I see that. But what if the effect isn't currently ongoing?

The planet will solidify at higher temperatures, and take longer to pull itself into a sphere than will the atmosphere. (I'm assuming self-gravitation can eventually make the planet spherical even if the planet is solid.) If there's a liquid core, it would likely have denser material, flowing more easily, and could become more spherical, while the more rigid outer layers and crust maintained the ellipsoid shape. So it's not obvious to me that gravity will be uniform over the surface if the planet isn't of uniform density.

[Agemegos]

Originally Posted by Anaraxes

So it's not obvious to me that gravity will be uniform over the surface if the planet isn't of uniform density.

It won't be if the planet is rotating, and we see this for example in the fact that pendulum clocks run slow when you take them from Paris to Cayenne.

But this isn't a matter of whether the acceleration due to gravity is equal over the surface. It's a matter of whether atmospheric pressure is. Look at it this way:

Sea level on the surface is going to be defined by whether a parcel of water would be inclined to flow away from elevations. If water at one point on the surface has higher energy than at another point, then it will tend to flow over the surface to the low-energy point, resulting in an equilibrium where water at the surface has the same gravitational-potential plus rotational-kinetic energy as at every other point on the surface.

Air is a fluid, so it will do the same. Since the gravitational + rotational effects at the surface are zero on water, they must also be zero on air. The gravitational + rotational effects don't make air flow over the surface. But if they produced differences of pressure, those would make air flow over the surface. But they don't make air flow over the surface, therefore we know that they don't produce differences of pressure. The pressure of air at sea level does not vary over the globe as a result of the combined action of gravity and rotational effects.

Therefore the only way that the air pressure at the equator could be significantly lower than that at the poles would be if the equatorial regions were well above sea level and the poles at sea level. The elevations required would be more than ten thousand feet.

So does the planet have an enormous equatorial belt of highlands and plateaus, standing 15,000 feet or so higher than the equatorial bulge produced by rotation, and large oceans at both poles? It seems that it must.

There are two main categories of such conditions: either the equatorial highlands are in hydrostatic equilibrium or they aren't.

If they aren't, that is if the mass of the planet is distorted out of shape, then the condition is not going to persist for very long. The pressures imposed by the weight of overlying rock at modest depths in the mantle of a planet greatly exceed the material strength of rock, and over a scale of millenniums the mantle material flows like a viscous fluid. The accumulation of thousands of metres of ice during the glaciations forced down the crust in the glaciated areas and displaced mantle material into peripheral bulges. But 11,000 to 15,000 years after the ice melted the Earth has gone most of the way towards recovering its shape. With 15,000 feet or so of equator-girdling bulge this planet would have enormous unequalised pressures in its mantle, would be rebounding comparatively quickly, and would be experiencing vigorous seismic activity and comparatively rapid sea-level rise on the borders of the equatorial bulge.

The alternative, which I didn't consider before, is that the equatorial highlands might be in isostatic equilibrium in the manner of continents: that is that they might consist of enormous plates of less-dense continental crust, thick and rigid and floating higher in the mantle than comparatively thin and weak oceanic crust. I would have to ask a geophysicist whether such a configuration of continents is plausible, and whether there is a limit to the height of continental plateaus.

In any case, water unless constrained would have flowed away from the low-pressure areas for the same reason that the air did (whatever that was), which would leave the high-pressure areas under deep oceans and the low-pressure areas high and dry.

[MrBackman]

Originally Posted by Mr Frost

I suggest that instead one considers either that Traveller exists in a universe with slightly different laws of physics
or that
a) the particle called a meson isn't the same particle we call a meson {perhaps science discovered a new order of such or found our ideas on the subject were wrong and some renaming/reordering happened}or
b) they plain figured out a way to alter its' properties .
.

That is exactly the same as admitting defeat. The problem as (and still is) to find a workable alternative to mesons in meson guns, an alternative that might actually work the way mesons guns are supposed to work in Traveller. Saying that mesons are different particles than what we call mesons and/or that they have different properties is in my view the canon way to deal with it.

If only astrophycisists had any ideas on what their cold dark matter WIMPS were we could use them, if some of them would actually decay in sane timespans. If neutrinos decay by the weak force that would be cool too.

[MrBackman]

Originally Posted by hal

I'm just a wee bit curious.

What would change in the Traveller Universe is Meson technology were not available?

The meson defense sites would no longer be an issue.
The meson offensive technology would no longer be an issue.
Meson communications would presumably no longer be available.

How would that change the overall strategy for something like CT's HIGH GUARD?

Hmmm. That would something interesting to ponder.

Meson communicators could just as easily be neutrino communicators as we know they have fairly portable neutrino detectors and any powerplant is also a neutrino emitter.

The sort of canon idea that Solomani won the war against the Vilani by inventing meson guns would have to go as well.

I'd ditch meson guns at the drop of a hat if it wasn't for several adventures where deep meson sites figured extensively in my super long lived Traveller campaign (started 1985, still going).

If I was to ditch meson guns I would ditch the damper boxes and nuclear damper screens against nukes too. Nukes can just as easily be dealt with by lasers shooting down missiles, at least in space, and do we really need mini nuke Californium firing autocannons in Traveller?