Icosahedron
SOC-14 1K
Hmm, I think maybe I wasn't understanding your PG theory after all, Aramis, but it may suffice to get my own grey cells working on the problem again...
Gravity and deckplans
- Thread starter Renaissance Man
- Start date
Icosahedron
SOC-14 1K
http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=13505
And in case this doesn't come out as a link - which it probably won't because I'm Computer-0
"Grav Skimmers" page 2 of Imperial Research Station.
So many questions...
Like, for instance, what is gravity?
IIRC, according to Einstein it's the space-time curvature associated with the presence of mass-energy.
If that helps any.
Edit: Woo-hoo, it came out as a link!!!
Renaissance Man
SOC-12
IIRC, according to Einstein it's the space-time curvature associated with the presence of mass-energy.
If that helps any.
Thanks for the thread link Icos. But now you've opened Pandora's box :devil:
If gravity is simply a product of the presence of mass-energy, why wouldn't we feel the lack of gravitation immediately if the sun were to spontaneously disappear? (In a previous thread someone said the effect would only be felt in 8 minutes, since gravity effects were supposed to travel at the speed of light.)
Why is gravity supposed to be transmitted via the graviton instead of just... there? If the presence of mass/energy itself automatically connotes the presence of space-time curvature why does there need to be a medium of transmission at all? If gravity is being exerted/radiated out from a massive body, like other flavours of energy, wouldn't it be slowly depleting the matter/energy that generates it, causing it to slowly change to a lower energy state?
Gravity is distinguished from all the other forces in the universe as being very weak - but is it really a force at all? It's hard for me to reconcile the notion of gravity as a force with the notion of gravity as a passive element of space-time topography.
I know I've got a problem here - I'm only very loosely familiar with the theories of physics that underpin this question, so I'm asking what might otherwise seem self-evident. I got my science education from Discovery Magazine :smirk:
mass/energy has two observed effects, inertia and gravity. Gravitics implies these can be manipulated seperately from each other. I tend to think in terms of fields, rather than particles, Maxwell just makes more sense to me than Dirac (the Ph.ds all say it is equivilent in the end.)
By Mach's Principle, inertia is connected with mass' relation to the universe as a whole. I think this is how the maneuver drive works, and since it is interacting with the backgound mass of the Universe the proximity of stellar or planetary mass is irrevelant. It is more in line with the new Process Physics than classical relativity, but I am comfortable with that.
Manipulating gravity without affecting intertia allows you to create a gravity field, an "illusiionary mass" that interacts with real-world mass. You want to lift a four-ton air-raft, just create a negative five ton gravity field and watch the earth-sized planet push you way at 2 m/s2. TANSTAAFL, you still have to feed energy into the system so the faster you go, power goes up by the square of velocity. It also doesn't work well unless you have a planetary mass right handy. But if you have the power it works out to a planetary diameter or so before the gravity you are pushing against gets too weak to push back.
Some trick for ship's gravity, create a field that normaly requires a huge mass and use it to manipulate the small masses of the crew. Of course, instead of creating the field of billions of tons of rock up to 6000 km under you, you create the field equivalent of a flat sheet of a few thousand tons just under your feet. friom the center of an infinite plate gravity does not diminesh with distance, and even with a finite plate you have a pretty large volume of 'stable' gravity.
By Mach's Principle, inertia is connected with mass' relation to the universe as a whole. I think this is how the maneuver drive works, and since it is interacting with the backgound mass of the Universe the proximity of stellar or planetary mass is irrevelant. It is more in line with the new Process Physics than classical relativity, but I am comfortable with that.
Manipulating gravity without affecting intertia allows you to create a gravity field, an "illusiionary mass" that interacts with real-world mass. You want to lift a four-ton air-raft, just create a negative five ton gravity field and watch the earth-sized planet push you way at 2 m/s2. TANSTAAFL, you still have to feed energy into the system so the faster you go, power goes up by the square of velocity. It also doesn't work well unless you have a planetary mass right handy. But if you have the power it works out to a planetary diameter or so before the gravity you are pushing against gets too weak to push back.
Some trick for ship's gravity, create a field that normaly requires a huge mass and use it to manipulate the small masses of the crew. Of course, instead of creating the field of billions of tons of rock up to 6000 km under you, you create the field equivalent of a flat sheet of a few thousand tons just under your feet. friom the center of an infinite plate gravity does not diminesh with distance, and even with a finite plate you have a pretty large volume of 'stable' gravity.
Supplement Four
SOC-14 5K
What if Traveller's control of gravity is a product of simply manipulating the polarization of the graviton?
In layman's terms, anti-grav in Traveller is a method of changing the "sign" of a negative graviton to a positive graviton, and having that positive graviton repel from another positive graviton (not unlike two like poles of a magnet).
The difference in a graviton and the magnet is, of course, that the graviton is massless.
Here's two wiki's on the real world theories: Graviton, and Gravitomagnetism.
Renaissance Man
SOC-12
Um. Yeah. I'm definitely a little out of my depth here
Do you remember the old days when Traveller was just a game? No theoretical physics was required, just a laser rifle so you could shoot the aliens.
Supplement Four
SOC-14 5K
Some other interesting theories about gravity and anti-gravity can be found here: Artificial Gravity, and Anti-gravity.
In the artifical gravity page, the magnetism section is interesting from a Traveller perspective, especially in the use of "deck plates".
In the artifical gravity page, the magnetism section is interesting from a Traveller perspective, especially in the use of "deck plates".
Renaissance Man
SOC-12
Do you remember the old days when Traveller was just a game? No theoretical physics was required, just a laser rifle so you could shoot the aliens.
Yeah, I know what you mean. It's about telling a story and having fun - but Traveller brings out my simulationist tendencies. I just get all hot and bothered about the science. And I like the idea of having an army of details at the ready for those moments where a bit of extra authenticity is required.
Supplement Four
SOC-14 5K
Exactly. Gawd, D&D was so much easier to ref. You want a pully? Throw a rope over that tree branch yonder. You've got some leverage now. Put your back into it. PULL!
Traveller is more like: How do the deck plates work, exactly? If we set it to zero on the bridge, is it an instantaneous "off", or does is gradually tick down to 0 Gs?
I'll think to myself, "Hell, I don't know!" Then smile, make a quick decision, and say, it's electricity-based. It's instant "off".
And, then I'll hope to hell someone doesn't know more about that than I do.
Captain Midnight
SOC-12
Alas, I game with some folks who have areas they're really expert in -- one has a Ph.D. in mechanical engineering and is a robotics researcher for the US Navy, another is working on a Ph.D. in particle physics, and another is a self-described "gun freak". They'll accept explicit handwaving for the sake of a game's story, but if I try to pull something out that I don't understand well, they can and will provide corrections.
This bogs down the game, as you might expect, and breaks the mood as well. There's some "suspension of disbelief" that has to go on with a lot of Traveller technology, and for our group, it helps if I can let them know that they ought not nitpick some things. It's fine to have discussions afterwards, where obscure topics can be discussed and we can come to some sort of agreements about how different facets of the universe might work, but having this discussion right after the sensors pick up three Vargr corsairs headed for them is guaranteed to be the wrong time.
I always did the gravity plates as per a Star Trek tech manual: if you lose power, they gradually go out over a period of a few hours. There is no ping-ponging with gravity systems in MTU.
From TNG Tech Manual: 'The gravity field itself is created by a controlled stream of gravitons, much like those produced by the tractor beam. ... Power from the EPS is channeled into a hollow chamber ... suspended in the center of the cylinder is a superconducting stator. The stator, once set up to a rotational rate above 125,540 RPM, generates a graviton field with a short lifetime, on the order of a few picoseconds. This delay time necessitates the addition of a second layer of generators beyond 30 meters distance. The field is gentle enough to allow natural walking without a gravity gradient from head to foot... In the even of EPS failure, the stator will continue to provide an attraction field for up to 240 minutes, though some degradation to 0.8g will be noticed"
So I use ST handwavium for gravity systems.
From TNG Tech Manual: 'The gravity field itself is created by a controlled stream of gravitons, much like those produced by the tractor beam. ... Power from the EPS is channeled into a hollow chamber ... suspended in the center of the cylinder is a superconducting stator. The stator, once set up to a rotational rate above 125,540 RPM, generates a graviton field with a short lifetime, on the order of a few picoseconds. This delay time necessitates the addition of a second layer of generators beyond 30 meters distance. The field is gentle enough to allow natural walking without a gravity gradient from head to foot... In the even of EPS failure, the stator will continue to provide an attraction field for up to 240 minutes, though some degradation to 0.8g will be noticed"
So I use ST handwavium for gravity systems.
