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TOS-R ringed planets

Ronald Held

Vice Admiral
Admiral
After watching another ringed Class M world, I wonder what the Trek explanation is for so many ringed earth-like world?
I am not going to invoke the CG team liked to model and render ringed worlds.
 
Ronald Held said:
After watching another ringed Class M world, I wonder what the Trek explanation is for so many ringed earth-like world?

Every planet has a Roche limit within which an orbiting body will be torn apart by tidal stresses. Its distance depends on the radius of the planet and the density of the planet and its satellite.

So an Earthlike planet could certainly have rings for a certain amount of geologic time (all planetary ring systems are temporary formations, only lasting for a few tens of million years or so) if a smallish or loosely packed satellite, or maybe a captured comet, fell within its Roche limit and got torn apart.

Now, Gamma 2 in "Gamesters of Triskelion" was called a planetoid and appeared to be a relatively small body, so the Saturn-like rings seen here are more unlikely. It's possible if a loosely packed asteroid (a lot of them are just clumps of rubble and dust rather than solid masses) fell inside Gamma 2's Roche limit and got pulled apart -- but probably the rings wouldn't be as wide and delineated as shown.

That's my problem with the rings we've seen -- they've all been broad, Saturn-like rings. We have four ringed planets in this system and each set of rings looks different. Ringed exoplanets would presumably have similar diversity of ring types.

For what it's worth, I don't think any of the ringed planets seen in TOS-R have been Class M per se. The ones I recall were Mudd's Planet ("I, Mudd"), which was described as being Class K, "adaptable" with pressure domes -- suggesting something Marslike without enough atmosphere to breathe. The Tantalus Colony ("Dagger of the Mind") seemed to have a breathable atmosphere but a largely barren surface. And Gamma 2 here was pretty clearly an airless, Moonlike body covered in craters. A planet with a ring system might also have undergone geologically recent bombardment by debris from the body that broke up to create the rings, so it might not be especially livable.
 
Christopher, you may be correct on some of this, but I do not see it as likely given the width of the rings and the timescale they would be expected to last. I am not a celestial mechanics ring expert, so I cannot quantify any of this quickly.
 
Ronald Held said:
Christopher, you may be correct on some of this, but I do not see it as likely given the width of the rings and the timescale they would be expected to last. I am not a celestial mechanics ring expert, so I cannot quantify any of this quickly.

By that token, how likely is it that the human species would exist during a period of geologic time when Saturn has such a luxurious system of rings? It's a big galaxy; even if ringed planets are in a minority, there are still going to be a fair number of them, and it stands to reason that humans or other species looking for worlds to settle on might be more drawn to ringed planets than other ones.
 
The stability of rings appears to be directly related to the mass of the planet. (Note that we do NOT know, for certain, why some planets have rings and why they don't. We have THEORIES for why... but this is not the same as FACTS. Just keep that in mind!)

Now, given that every planet we've seen in reality with rings is far more massive than Earth, the obvious interpretation of this limited data set is that Earth-sized object generally do not maintain stable ring structures.

This really isn't hard to understand. It's basically a balancing act between orbiting speed and gravitational force... the region of stability is simply larger in the case of larger objects (like Saturn) and much smaller in the case of smaller objects (like Earth).

When I see this, I see the same thing as we've seen in the reworked Star Wars films... with explosions going, not in all directions, but in a planar circle. It's just a visual "trick" that the artists are fond of at the time that they do the work.

Kind of like lens flairs in computer games and relatively early CG. They're definitely cool to see, but they tend to be WAAAAY overused because the folks doing them lose their sense of proportion. ;)
 
Cary L. Brown said:
(Note that we do NOT know, for certain, why some planets have rings and why they don't. We have THEORIES for why... but this is not the same as FACTS. Just keep that in mind!)

A "fact" is merely an observation, a single data point. A theory is a model that codifies a set of "facts" (i.e. observed data) and explains their origins and relationships. It is a fact that apples fall from trees; it is a fact that the Moon orbits the Earth. Newton's Theory of Universal Gravitation, or Einstein's Theory of General Relativity, is a model that places those "facts" into a larger system that explains them and allows us to make predictions beyond known "facts." A fact is much less than a theory, because by itself it's just an isolated observation that could mean anything. It needs a theory to give it context, meaning, and predictive power. And theories are tested by observing new "facts" and seeing if they conform to the predictions of those theories.

So the goal of a theory is not to grow up into a real live fact. No, its goal is to gather more "facts" (i.e. data) that can be used to hone and improve the theory's precision as a predictive tool.

Now, given that every planet we've seen in reality with rings is far more massive than Earth, the obvious interpretation of this limited data set is that Earth-sized object generally do not maintain stable ring structures.

That is very flawed reasoning. For generations, people assumed that since every giant planet in our star system is in the outer part of the system while most or all of the rocky planets are in the inner part, it was therefore "obvious" that giant planets would always be found in the outer part of any extrasolar planetary system. But in recent years, we have discovered dozens of giant planets orbiting extremely close to their stars, throwing our old assumptions out the window. In science, "obvious" usually turns out to be a synonym for "wrong."

Even aside from that, it's shoddy thinking to jump to one "obvious" conclusion and ignore other possibilities. There's a different reasonable interpretation that instantly occurs to me. Giant planets are more likely to have a large number of moons and captured asteroids, therefore giving them a larger number of bodies that can fall within the Roche limit and break up, therefore increasing the probability that one will find them in possession of rings at any given time in their history. It's got nothing to do with their ability to maintain a ring structure, merely with their opportunity to do so. And since it's a matter of probability, it doesn't rule out the prospect of a terrestrial planet having rings, it just makes it a less frequent occurrence.

Or it could conceivably be that the reason our outer planets have rings isn't because they're bigger but because they're further from the Sun. Most of those rings are made of ice, and ice sublimates away to vapor when it's close to the Sun. Therefore, a planet of any size that's farther out from its primary star -- beyond what's called the "snow line" -- might be more likely to have rings than a planet of any size that's within the "snow line."

So you should never assume that the first, "obvious" explanation that occurs to you is the only one worth considering. A modicum of thought can usually produce other possibilities.


This really isn't hard to understand. It's basically a balancing act between orbiting speed and gravitational force... the region of stability is simply larger in the case of larger objects (like Saturn) and much smaller in the case of smaller objects (like Earth).

The false assumption there is that rings are stable. They aren't. As stated above, they're temporary formations, lasting for at most a few percent, maybe just a few tenths of a percent, of a planet's lifespan. They are formed when a satellite moves out of its region of stability into the region where it can't exist as a stable body and gets torn apart. It just takes a few dozen megayears for the debris to clear out.

Saturn's rings have already undergone noticeable changes in the quarter-century since they were first imaged up close. Some of the shepherd moons within the ring system are no longer there, apparently having been broken up by ongoing collisions. One of the ringlets in the innermost D Ring has become fainter and moved 200 km closer to the planet in the past 25 years. If there have been such noticeable changes in the rings' structure in a fraction of a mere human lifetime, they can hardly be said to be stable formations in an astronomical sense.
 
Christopher said:
Cary L. Brown said:
(Note that we do NOT know, for certain, why some planets have rings and why they don't. We have THEORIES for why... but this is not the same as FACTS. Just keep that in mind!)

A "fact" is merely an observation, a single data point. A theory is a model that codifies a set of "facts" (i.e. observed data) and explains their origins and relationships. It is a fact that apples fall from trees; it is a fact that the Moon orbits the Earth. Newton's Theory of Universal Gravitation, or Einstein's Theory of General Relativity, is a model that places those "facts" into a larger system that explains them and allows us to make predictions beyond known "facts." A fact is much less than a theory, because by itself it's just an isolated observation that could mean anything. It needs a theory to give it context, meaning, and predictive power. And theories are tested by observing new "facts" and seeing if they conform to the predictions of those theories.

So the goal of a theory is not to grow up into a real live fact. No, its goal is to gather more "facts" (i.e. data) that can be used to hone and improve the theory's precision as a predictive tool.

Now, given that every planet we've seen in reality with rings is far more massive than Earth, the obvious interpretation of this limited data set is that Earth-sized object generally do not maintain stable ring structures.

That is very flawed reasoning. For generations, people assumed that since every giant planet in our star system is in the outer part of the system while most or all of the rocky planets are in the inner part, it was therefore "obvious" that giant planets would always be found in the outer part of any extrasolar planetary system. But in recent years, we have discovered dozens of giant planets orbiting extremely close to their stars, throwing our old assumptions out the window. In science, "obvious" usually turns out to be a synonym for "wrong."

Even aside from that, it's shoddy thinking to jump to one "obvious" conclusion and ignore other possibilities. There's a different reasonable interpretation that instantly occurs to me. Giant planets are more likely to have a large number of moons and captured asteroids, therefore giving them a larger number of bodies that can fall within the Roche limit and break up, therefore increasing the probability that one will find them in possession of rings at any given time in their history. It's got nothing to do with their ability to maintain a ring structure, merely with their opportunity to do so. And since it's a matter of probability, it doesn't rule out the prospect of a terrestrial planet having rings, it just makes it a less frequent occurrence.

Or it could conceivably be that the reason our outer planets have rings isn't because they're bigger but because they're further from the Sun. Most of those rings are made of ice, and ice sublimates away to vapor when it's close to the Sun. Therefore, a planet of any size that's farther out from its primary star -- beyond what's called the "snow line" -- might be more likely to have rings than a planet of any size that's within the "snow line."

So you should never assume that the first, "obvious" explanation that occurs to you is the only one worth considering. A modicum of thought can usually produce other possibilities.


This really isn't hard to understand. It's basically a balancing act between orbiting speed and gravitational force... the region of stability is simply larger in the case of larger objects (like Saturn) and much smaller in the case of smaller objects (like Earth).

The false assumption there is that rings are stable. They aren't. As stated above, they're temporary formations, lasting for at most a few percent, maybe just a few tenths of a percent, of a planet's lifespan. They are formed when a satellite moves out of its region of stability into the region where it can't exist as a stable body and gets torn apart. It just takes a few dozen megayears for the debris to clear out.

Saturn's rings have already undergone noticeable changes in the quarter-century since they were first imaged up close. Some of the shepherd moons within the ring system are no longer there, apparently having been broken up by ongoing collisions. One of the ringlets in the innermost D Ring has become fainter and moved 200 km closer to the planet in the past 25 years. If there have been such noticeable changes in the rings' structure in a fraction of a mere human lifetime, they can hardly be said to be stable formations in an astronomical sense.
Ya know, Christopher... you REALLY REALLY REALLY need to start measuring how you express yourself. What do you do for a living again? What do I do for a living again? What's your educational background? What's mine?

Your post, just above, was simultaneously insulting, egotistical... and just plain incorrect. It's OK to disagree, even to argue.

But you fell into the same trap you did last time you and I had a discussion. You remember... when you were so adamant about informing me that I, since I'm not in the "publishing world" have no business talking about book publishing matters... and that the fall-off in sales of Trek books of certain types "obviously" is due to the decrease in interest, not due to the decrease in publishing of the sorts of things that people actually want to BUY, as I had proposed.

I have to wonder just what it is that's wrong with you.

Your explanation of why "facts" are less significant than theories simply demonstrates that your understanding of this is, at best, incomplete.

A fact is something that is undeniable, and utterly beyond dispute.

A theory is a partially-supportable idea of WHY something may be the case.

A hypothesis is an as-yet-unsupported idea of why something may be the case.

As with all things, science is really iterative, so something which meets the requirements of a fact may also be used as an observation for additional hypotheses or theorum, of course. Theories may exist without any hard factual support, either... provided that they are supported by other well-accepted theories. But no theory can be accepted as fact unless its support is based upon fact, rather than other theory, as well.

Hypotheses are, by definition, REQUIRED to be challenged. Theories are always, without exception, SUBJECT to challenge. But facts are not.

That's fundamental. That you miss it pretty much invalidates your attempts at sniping at me.

The funny thing is, I was largely AGREEING with your earlier posting. But you can't seem to accept that sort of thing... your ego seems to get in the way. :rolleyes:

I STRONGLY recommend that, in the future, you don't use terms like "shoddy" or "flawed" to describe someone else's perspective unless you're absolutely certain that you actually KNOW MORE than the other person. And even if you do... it's pretty damned poor form.

One last note... "stable" is not a "yes" or "no" term as used here. You attempt to "correct" me but you fail to acknowledge the very phrasing of my original comment.

There is, in reality, only one singular point of stability for anything. That's bicycles, aircraft, balanced stacks of books... anything. So nothing... EVER... is "truly stable" as you seem to want to define the term. Everything that exists even an infinitesimally small distance away from the theoretical "point of stability" is, by definition, unstable. However, if the values (let's say, since we're talking about rings, that we're talking about radius of rotation and velocity of orbit) are very close to the theoretical nominal value, the amount that they tend to "fall away" from the point of stability over time is very small. The system we're talking also contains object-to-object gravitation, which tends to draw the ring into greater stability... but also has a random object-to-object kinetic energy transfer (ie, COLLISION) element which tends to throw it lower stability.

We THINK we know what's going on there. But, again, Christopher... we have not OBSERVED a ring system created and then dissipated. We have a theory as to what we THINK is happening. There's good science supporting it, but to treat it as though it's beyond questioning is simply WRONG.

Sorry if you think otherwise. But if you DO think that, you're simply demonstrating that you don't understand the topic as well as you think you do.
 
Cary L. Brown said:
Your explanation of why "facts" are less significant than theories simply demonstrates that your understanding of this is, at best, incomplete.

A fact is something that is undeniable, and utterly beyond dispute.

A theory is a partially-supportable idea of WHY something may be the case.

No, you're absolutely wrong about that. It's a widespread misconception based on the laypersons' use of the word "theory," but any scientist (or anyone with a degree in the sciences, like my bachelor's degree in physics) will tell you that's simply not what the word "theory" means in a scientific context. It's also quite easy to verify by doing a modicum of research:

http://en.wikipedia.org/wiki/Theory

In science, a theory is a mathematical or logical explanation, or a testable model of the manner of interaction of a set of natural phenomena, capable of predicting future occurrences or observations of the same kind, and capable of being tested through experiment or otherwise falsified through empirical observation. It follows from this that for scientists "theory" and "fact" do not necessarily stand in opposition. For example, it is a fact that an apple dropped on earth has been observed to fall towards the center of the planet, and the theories commonly used to describe and explain this behaviour are Newton's theory of universal gravitation (see also gravitation), and general relativity.


But no theory can be accepted as fact unless its support is based upon fact, rather than other theory, as well.

No theory is ever "accepted as fact," because a fact is merely an axiom, a data point. A theory is a model. Anyone who thinks that the goal of a theory is to "prove it as a fact" is swallowing a popular myth. The goal of a theory is to be used to make predictions beyond existing data, which can then be tested by gathering more data, so that the theory can be refined still further. Nobody is ever hoping to get a theory to a point where it's fixed and unquestioned and unchanging, because the whole point of theory is to serve as a tool for asking questions and refining our understanding of how the universe works. A theory is the model for how an aspect of the universe works, so it's supposed to undergo ongoing change and refinement alongside our understanding of things.

The funny thing is, I was largely AGREEING with your earlier posting.

My whole point was that it was indeed possible for Earthlike planets to have ring systems. You said "the obvious interpretation of this limited data set is that Earth-sized object generally do not maintain stable ring structures." If you thought you were agreeing with me, then you must have fundamentally misunderstood my point, because in fact you were saying the exact opposite of what I was saying.
 
Christopher said:
Cary L. Brown said:
A theory is a partially-supportable idea of WHY something may be the case.

No, you're absolutely wrong about that. It's a widespread misconception based on the laypersons' use of the word "theory," but any scientist (or anyone with a degree in the sciences, like my bachelor's degree in physics) will tell you that's simply not what the word "theory" means in a scientific context...

Indeed, what CLB describes is a hypothesis, not a theory.

And the next step up from a theory is a law, but those are few and far between.

I think, though, we might need to distinguish between a fact and an observation, although one could argue that they basically are the same.
 
Christopher said:
Cary L. Brown said:Your explanation of why "facts" are less significant than theories simply demonstrates that your understanding of this is, at best, incomplete.

A fact is something that is undeniable, and utterly beyond dispute.

A theory is a partially-supportable idea of WHY something may be the case.
No, you're absolutely wrong about that. It's a widespread misconception based on the laypersons' use of the word "theory," but any scientist (or anyone with a degree in the sciences, like my bachelor's degree in physics) will tell you that's simply not what the word "theory" means in a scientific context. It's also quite easy to verify by doing a modicum of research:

http://en.wikipedia.org/wiki/Theory
For God's sake, Chris, get this. YOU ARE A WRITER. I DO SCIENCE FOR A LIVING.

I am not a "layperson" in this regard. YOU ARE.

And relying on WIKI as an indisputable source is funny. I use it often enough... we all do... but WIKI is full of inaccurate material. For instance, there's hardware I've got installed on aircraft, where I know very specific information relating to that aircraft, which is described in totally MADE UP ways on WIKI.

It's a good starting point... but honestly, Chris, if you think reading a WIKI page qualifies as "doing research"... well, you're demonstrating that you've never done any REAL research. (I've done plenty of that, on the other hand.)
In science, a theory is a mathematical or logical explanation, or a testable model of the manner of interaction of a set of natural phenomena, capable of predicting future occurrences or observations of the same kind, and capable of being tested through experiment or otherwise falsified through empirical observation. It follows from this that for scientists "theory" and "fact" do not necessarily stand in opposition. For example, it is a fact that an apple dropped on earth has been observed to fall towards the center of the planet, and the theories commonly used to describe and explain this behaviour are Newton's theory of universal gravitation (see also gravitation), and general relativity.
That said, this PARTICULAR Wiki article is actually pretty good. (That's the nice thing about it being totally open... total falsehoods don't last long).

However, your argument seems to be that I'm somehow disagreeing with that, which is PATENT BULLSHIT, Chris. What's said there is that you can have a fact... in this case "apples fall towards the ground" and a theory... in this case, the mathematical model Newton derived which uses 9.81 meters per square-second as the acceleration due to gravity at sea level.

OF COURSE the fact and the theory aren't somehow "in contradiction" to each other. The fact is indisputable. The theory, however, is not. I use gravity in the overwhelming majority of day-to-day tasks I perform (since virtually every vehicle I work on operates in the terrestrial sphere). It is now accepted as a FACT that, at sea level, the acceleration due to gravity is a specific value, and at different altitudes you have different values for G. It's not really a theory at all anymore.

But there ARE theories involving gravity. And there are hypotheses as well. The theories tend to relate to the differentials in gravity as measured due to assymmetricalities in the shape and mass-distribution of the planet (everything from mountain ranges to oceans). These are based upon measurements, but are not fully developed and are still subject to evaluation and criticism, unlike the basic stuff of Newton.

I'm still just stunned that a NOVELIST is trying to lecture me on SCIENCE. :rolleyes:
But no theory can be accepted as fact unless its support is based upon fact, rather than other theory, as well.
No theory is ever "accepted as fact," because a fact is merely an axiom, a data point.
BULLSHIT, Chris.

A fact is anything which is known with absolute certainty. Once a theory has been proven, beyond dispute, it becomes acknowledged as fact. It ceases at that point to be a theory.

It is a FACT that the acceleration due to gravity at sea level is 9.80665 m·s^2. At one point, this was a theory, because it had not been established, demonstrated repeatably and in a fashion transparent to peer review. Once it was PROVEN, it ceased to be theory and became accepted fact.

THAT IS HOW SCIENCE WORKS, CHRIS!

An observation is made.
A potential explanation for the observation is proposed. This is called a hypothesis.
If the hypothesis proves to be consistent with known facts, and if the hypothesis cannot be proven to be inconsistent with the same, it may be considered to be no longer a hypothesis but rather a theory.
Every theory is subject WITHOUT RESTRICTION to being challenged and questioned. There can be multiple, contradictory theories for any given set of observations. Only one can be true, of course.
Only only if a given theory is demonstrated in a clear, unambiguous, and 100% repeatable fashion to be true may it cease to be identified as a theory and become an acknowledged fact.

The WIKI article basically states that you can have a theory and it doesn't say that you don't also have the OBSERVATION that led to that theory. Which is true... but which is not particularly useful to say.

Yes, an observation is a form of fact as well. As I said before, though you seem to have ignored the point, science is an ITERATIVE PROCESS. Every fact leads into further hypotheses, some of which become theories, and some of which eventually become proven facts... which then lead into further hypotheses... and so on and so on.)
A theory is a model. Anyone who thinks that the goal of a theory is to "prove it as a fact" is swallowing a popular myth.
Chris, you really REALLY need to stop being so impressed with yourself. You're making yourself out to be an ass... you really are.

I am not "swallowing a myth." I do this stuff for a living. You write Star Trek books for a living.

What do you think the goal of science is, Chris? Since you seem to not "get it," I'll help you understand. The goal of science is to understand the universe we live in. Plain and simple.

We observe... we try to explain... we come up with a model. But you seem to think that once we have a model, that's the end of it?

I've heard your argument before. It's typically put forward by people who want to say that a theory must be treated as being TRUTH and must never be questioned. Is that your objection? You disagree with my statement that theories are, and MUST BE, subject to challenge? I hear that mainly from devout atheist types who attempt to claim that the theory of inter-species evolution must be treated as though it's TRUE (as opposed to being treated, appropriately, as a valid THEORY). I also hear it from Al Gore and his groupies. But you never hear it from people who work in the sciences.
The goal of a theory is to be used to make predictions beyond existing data, which can then be tested by gathering more data, so that the theory can be refined still further. Nobody is ever hoping to get a theory to a point where it's fixed and unquestioned and unchanging, because the whole point of theory is to serve as a tool for asking questions and refining our understanding of how the universe works. A theory is the model for how an aspect of the universe works, so it's supposed to undergo ongoing change and refinement alongside our understanding of things.
Not really true. You're correct in describing how theories are used... but you seem locked into this idea that we can never establish something as being a fact. This is demonstrably false, even by the example of the WIKI article you posted above. It is a FACT that gravity at sea level is 9.80665 m·s^2. This was not always known. At one point it wasn't accepted as fact.

This does not mean that we know everything, or even much at all, about what the actual mechanism of gravity is. But scientific method led to identifying a fact... that an object travels from this height to this height in this time... to a hypothesis... to a theory... which then got refined over time... and which eventually was so fully developed, so fully supported, and so utterly indisputable that it is now simply acknowledged as a fact. Which allows it to be used in the further development of OTHER hypotheses, other theorums, and eventually other known facts.

The model isn't the theory. A theory can, and usually DOES, contain a model. But that's not what defines it as a theory.
The funny thing is, I was largely AGREEING with your earlier posting.
My whole point was that it was indeed possible for Earthlike planets to have ring systems. You said "the obvious interpretation of this limited data set is that Earth-sized object generally do not maintain stable ring structures." If you thought you were agreeing with me, then you must have fundamentally misunderstood my point, because in fact you were saying the exact opposite of what I was saying.
Well, you stated that it's possible for them to have ring systems for very short periods of time, as I recall.

I didn't disagree. Hence my discussion of stability before (which you obviously DID READ, though you again seemed to want to pick a fight rather than discuss). The idea being that the statistical likelihood of a planet forming a stable right structure is much higher for a more massive, larger body.

I also pointed out that this is at best theory. That is... it may fit certain mathematical models we've developed that we believe describes the formation of such ring structures. But I also emphasized that since we have nothing but that theory... and it's fairly poorly supported right now... it's equally valid to hypothesize that earth-sized planets might not be able to form rings at all. And there is theoretical work which states as much.

We've never seen one. We've seen rings around our system's largest and most massive bodies, however. So, given our limited body of observation, it's easier to support the theory that smaller planets cannot sustain ring structures for any meaningful period of time, or even at all, than it is to say that "they just seem to be random occurrences" which is what you'd think from watching TOS-R.

Which takes us back to the original point of this thread.

TOS didn't have ringed class-M planets. The only ringed planet we saw in TOS, as I recall, was in the sky of Rigel in "The Cage." Now, we're being given a whole series of planets with rings. This is inconsistent with our limited knowledge of the universe and is statistically HIGHLY unlikely given the mathematical models which demonstrate that ring structure stability is dependent on the size and mass of the parent body.

In other words, it seems that TOS-R is doing it "just because it looks cool." It fits with neither observation nor established theory.

Do you disagree with THAT?
 
A fact is anything which is known with absolute certainty. Once a theory has been proven, beyond dispute, it becomes acknowledged as fact. It ceases at that point to be a theory.

It is a FACT that the acceleration due to gravity at sea level is 9.80665 m·s^2. At one point, this was a theory, because it had not been established, demonstrated repeatably and in a fashion transparent to peer review. Once it was PROVEN, it ceased to be theory and became accepted fact.

I'm going to tread carefully into this discussion, because there seems to be a difference in approach that is going unacknowledged. Cary seems to be approaching the word "theory" from the practical standpoint, like that employed by an engineer. Christopher, on the other hand, is using the word as a theoretical or experimental physicist would use it.

A scientist might say that a theory is accepted as fact, but not that it is fact. The very example that Cary employs regarding gravity is a splendid case in point -- there is new data accumulating daily that gives additional insight into the nature of gravity, and the existing tension between quantum theory and classical physics guarantees an amended understanding at some point. It might not make a practical difference at human scales or earthbound applications, but it will represent an enlarged understanding of the subject, and reveal existing theory to be incomplete vis-a-vis that understanding.

I think these are usage issues -- Newton's laws of motion are theories as I understand the term, revealed to be an incomplete understanding of the subject by Einstein, whose own work in the area will be revealed as incomplete by something else -- perhaps a GUT.

In absolute terms, I think Christopher is using the word correctly, but in practical terms, I think Cary's usage is understandable.
 
It doesn't seem logical that a spacefaring civilization could exist or occur on such a planet. Nifty image, questionable science.

Wouldn't even small rings cause incredible difficulties with rocket launches, satellites, space stations et al.
 
aridas sofia said:
I think these are usage issues -- Newton's laws of motion are theories as I understand the term, revealed to be an incomplete understanding of the subject by Einstein, whose own work in the area will be revealed as incomplete by something else -- perhaps a GUT.

No, because "theory" does not mean "unproven idea." A theory, scientifically speaking, is a model that explains how and/or why something works. Or, more precisely, it's a model that explains an existing set of observations and experimental results in a way that fits them into a systematic framework and thereby makes testable predictions beyond them.

Now, scientists don't talk about "proof" -- just testing and results. Some theories have been discredited by experimental results and therefore discarded. Some theories are useful as predictive tools in most cases but have flaws, and are therefore refined to make them work better. Some theories have been consistently successful at predicting real-world results for generations and are thus accepted as trustworthy models of reality, but even so, their predictions are meant to be tested by observation and experimentation, not taken on faith. If anything is "proven," it's not theories, it's their individual predictions, one by one. The theory remains dynamic and growing, a working tool to be used on a daily basis rather than an edict meant to gather dust on a pedestal. But even if all a theory's predictions are verified, it's still called a theory, because the term refers to the structure and purpose of the thing, not its status.

A law is essentially an observation, a description. Kepler's Laws of Planetary Motion describe how planets move around the Sun but do not explain why. A theory is something that codifies and explains a set of observations; Newton's Theory of Universal Gravitation explains the reason behind Kepler's Laws. As for Newton's Laws of Motion, they are also descriptions for how objects in motion behave; those laws were later codified within the theories of mechanics and later determined to be approximations of equations within the theories of relativity.

Then there's something like Bode's Law, which made the observation that the orbital distances of the known planets followed a mathematical progression. The law didn't try to explain why this happened, it simply described it. And the discoveries of later planets -- Neptune in our system, exoplanets in other systems -- have shown that there is no real mechanism underlying the "law"; it's just something that happened to occur in this one case. People have tried to come up with theoretical models that explained Bode's Law, but the law itself has been discredited by further observations.

At best, a law is a part of a theory -- a single axiom or assertion within it. You construct a theory by taking a set of laws/axioms/results that are accepted as true and building a broader framework that puts them in context and explains why they exist. It's that breadth and inclusiveness that makes something a theory. I like to make a simple geometrical analogy: if your observations are a set of individual points on a graph, then the equation for the curve that links them together is the theory. If there's more than one curve that passes through all those points (or within their error bars), you have competing theories -- but those theories make predictions about where other points will fall, because the equation can tell you the entire shape of the curve, not just the part you've measured. So when you take measurements somewhere else -- test the predictions of the theory -- you can find out which theory/curve they conform to and discard the others. That's what "theory" means to a scientist: something that isn't just one thing, but is a whole broader system that the known facts and laws fit into and that points the way to new findings beyond the known facts and laws.

Maybe that's why people think a theory is something incomplete and unproven -- because the whole point of a theory is to be open-ended, to raise new questions beyond the known answers. It's a system rather than a single thing.


Starlock said:
It doesn't seem logical that a spacefaring civilization could exist or occur on such a planet. Nifty image, questionable science.

Wouldn't even small rings cause incredible difficulties with rocket launches, satellites, space stations et al.

Why would they? Space is three-dimensional. You don't have to send up your rocket in the plane of the rings. Just go around them.

Of course, an inclined orbit would still have to intersect the ring plane, but if the rings are small, you just avoid that particular orbital altitude. Even if you do have to pass through the rings, the level of danger is dependent on the composition and density of the rings. If they're made mostly of small dust particles, it's not that great a risk. At least one space probe has flown directly through Saturn's rings and survived. The average separation between particles in Saturn's rings is about a kilometer, and most of the particles are no bigger than a house. Although if you had to pass through that twice per orbit for some length of time, then it could be a problem. But most ring systems probably aren't as extensive as Saturn's -- certainly not around terrestrial planets.

Anyway, as I mentioned, the three ringed planets we've seen in TOS-R (Mudd's Planet, Tantalus Colony, Gamma 2 outpost) have all been pretty much barren and have not possessed indigenous spacefaring civilizations.
 
Christopher said:
aridas sofia said:
I think these are usage issues -- Newton's laws of motion are theories as I understand the term, revealed to be an incomplete understanding of the subject by Einstein, whose own work in the area will be revealed as incomplete by something else -- perhaps a GUT.

No, because "theory" does not mean "unproven idea." A theory, scientifically speaking, is a model that explains how and/or why something works. Or, more precisely, it's a model that explains an existing set of observations and experimental results in a way that fits them into a systematic framework and thereby makes testable predictions beyond them.

You're right, and I definitely gave the wrong impression by that first sentence. I was conflating the Principia's Laws of Motion and Theory of Universal Gravitation, which was a mistake.

And yet, I was very careful never to say "theory" in any way meant "unproven idea." I wrote that a theory is an incomplete understanding, which is true. It may seem to be a distinction without a difference, but it's not. There is no intent to "prove" a theory. But a theory usually (if not always) reflects an incomplete understanding. The point is to learn more, not to prove something, and thus close the door to further learning.

A current freshman college physics text reads:

"These patterns are called physical theories or, when they are very broad and well established, physical laws...nearly all the principles in this book are so solidly established by experimental evidence that they have earned the title physical law."

That is from the eighth edition of Sears and Zemansky's College Physics. And it is of course inaccurate. But I think it is more likely that the authors were mindlessly carrying forward a distinction form an earlier time, rather than simply pulling it out of the air.

For 200 years, the Theory of Universal Gravitation was an irrefutable standard of scientific truth. In his Metaphysical Foundations of Natural Science, Kant expressed his belief that Newton had proven beyond any doubt that what happens within this world is governed entirely by scientific laws.

I think that kind of belief underlies the distinction in the Sears and Zemansky text -- an earlier confidence in a finite, ultimately comprehensible universe that could be wholly described by "laws". They might not be proven, but they also wouldn't need further elaboration because they would reflect everything pertinent about a subject. That confidence has long since melted away, and been replaced by a more pragmatic understanding of the universe. "Theory" and "law" then and now distinguish between a conceptual framework for reasoning about facts, and an observed regularity among facts. I believe that in Newton's time there was a higher degree of confidence than there is now in the ultimate utility and durability of a theory's framework, however.

I should point out that this is an impression I have from my recollection of Kant, and that I am not an etymologist nor do I have any specialized knowledge on the history of science.
 
It's likely that rings would play havoc with a terrestrial planet's climate. The catastrophic breakup of a satellite to form them wouldn't be great for anything living on the planet, but the prolonged shading of portions of planet would greatly affect everything from currents in the air and ocean to ice distribution.
 
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