The mysterious Beta Grove, revisited. SPOILERS

rachel on 26/5/2008 at 15:39

Sort of. Another way to look at it is with a simple sheet of paper. Draw a point A in one corner and a point B in the opposite corner. The paper obviously represents space, and the distance between A and B is the distance you'll have to travel using conventional physics.

Now take a pin and fold the paper until you can pin A and B to each other, and you got your wormhole. The distance between A and B is now much smaller in the wormhole (the pin) than in space (the sheet of paper)

RocketMan on 26/5/2008 at 16:12

Very true, although your example Raph, is a prime example of Star Trek's warp drive, whereas NV's tube/ball example is more akin to wormholes. Either way, the distance-metric across space-time decreases along the new path.

Wormholes have a few different varieties. The Einstein-Rosen bridge of a rotating black hole poses many major challenges that need to be overcome like extreme tidal forces, blue-shifted radiation cooking you, super-luminal velocities as you approach the singularity and a wormhole throat with a topology goverened by quantum mechanics, which is completely probabalistic and will almost certainly collapse on you before you pass through it.

There are a couple of other types though that are more friendly :D

Nameless Voice on 26/5/2008 at 20:33

Quote Posted by RocketMan

His example was basically the same as mine?

I thought that the Star Trek warp drive worked by making a "warp bubble" of space and moving that bubble, so that, while the ship doesn't really move, the bubble does. Somewhat similar to how the SS2 FTL technology might work.

RocketMan on 26/5/2008 at 22:12

Sorry, what I meant was, a wormhole is truly a tunnel whereas the warp drive principle is more a distortion of space (caterpillar-like movement) that requires no tunnel. However after reading a bit about star trek warp drive, I realize it's not quite what I thought it was. Space folding is something else I was confused with I guess.

kodan50 on 27/5/2008 at 01:17

Yay, some math! looking into the distance and time from jettison point to landing point.

Quote Posted by Chimpy Chompy

Uncia, your numbers are a pain to follow. Can't you use powers of ten?<br />Let's see, a trillion is 10^12, right (or is it something else? never use the word in science)?

So distance travelled, s = 67*10^12 miles = 1.078*10^17 m.<br />Time for journey, t = 40 years = 60^2*24*365*40 seconds = 1.261*10^9s.

Accelerate half the journey, a = s/(t/2)^2 = 0.271 m/s^2. Which is only about 0.028g. (No\Eyes, g is just a unit, can use it anywhere). Just check max velocity:<br />v = a * (t/2) = 1.7098*10^8 m/s. Which is a bit over half the speed of light. Which means we ought to be looking at this relatvistically. Shit. I hate that stuff.

I know I failed school in sixth grade, but I think a few of these equasions need to be adjusted a little, and the calculations should be updated. I was slacking off at work today (like I always do) and decided to write out the speeds of travel that you would have to do to arrive 67 trillion miles. Please correct me wherever I am wrong.

Quote:

If the year point of reference is 2072, and the grove jettison was April, then the leap year would start after the current leap year.

2072 - Start point (Ref starts on Leap year, date is after Feb, leap year does not count this year.

2112 - 40 years, 10 leap days
(1 leap year every 4 years. Are leap years still counted in the future? According to XP they are! :))

Add 10 days to the calculation, and divide by the additional 10 days.

365 days * 40 years + 10 leap days = 14610 days

14610 days in the 40 year span * 24 hours in a day * 60 minutes in a hour * 60 seconds in a minute = 1,262,304,000 seconds from April 2072 to April 2112

67 trillion miles is approximation.

40 years is an approximation.

Remember the grove was jettisoned within Saturn's 3rd moon orbit, I believe. I have no idea how far away from the planet the moon is, the position of the stations on the moon's orbit, and it's distance from that point to the planet in Tau Ceti...

This equation is base on the approximations given to me in the above quote (and furthermore, from that quote's predecessor).

To reach a destination of 67 trillion miles over the course of 40 years, you would have to travel at an average speed of ~85,401,773.265 m per second, ~85,401.773km per second, or ~53,077.547 miles per second.

67,000,000,000,000 miles / 1,262,304,000 seconds = ~53,077.547 miles per second.

67,000,000,000,000 miles * 1.609 Km(per mile) = 107,803,000,000,000 km

67,000,000,000,000 miles * 1.609 Km(per mile) * 1,000 m(per km) = 107,803,000,000,000,000 m

107,803,000,000,000 km / 1,262,304,000 seconds = ~85,401.773 km per second.

107,803,000,000,000 km * 1,000m(per km) / 1,262,304,000 second = ~85,401,773.265m per second.

1 mile = 1.609 km

If a light year is 9,460,730,472,580.8 miles, then it would take ~7.08 years to reach Tau Ceti from Saturn's moon at the speed of light.

Light travels at 186,000 miles per second, or 669,600,000 miles per hour

The grove would have to traveling at an average of ~53,077.547 miles per second, or ~191,079,169.2 miles per hour.

67,000,000,000,000 Miles / 1,262,304,000 seconds / 60 seconds in a minute / 60 minutes in an hour.

The grove would have to traveling at an average of ~85,401.773 km per second, or ~307,446,382.8 km per hour.

67,000,000,000,000 Miles * 1.609 Km(per mile) / 1,262,304,000 seconds /60 seconds in a minute / 60 minutes in ann hour

The grove would have to traveling at an average of ~2/7th (Or, ~29%) the speed of light.

I couldn't get the rest thought. (The one that factors in G-forces and how that would effect the grove.) Other very important factors are, do we know for certain that it took the 40 years to crash, or is that how long it was from jettison point to discovery? Also, the original video from System Shock should be able to tell us the speed of the jettisoned by making an educated guess. (If we have an enemy stand on one end of the medical level, and we use the targeting system and move to the other end, we can see about how big medical level is in meters. Then, we can apply that to other levels, estimate the size of the station in a whole, then measure the time and distance the grove flew during the jettison process.) Also, is the 67 trillion miles from Earth or Saturn's moon? Is the distance beteen Earth to Saturn even enough to change the estimate enough?

I don't really need an answer as long as these figures can be generally accepted. I know everyone already knows all this though. I just wanted the last several minutes to mean something :D

Meh, I have too much free time on my hands I guess..

Zygoptera on 27/5/2008 at 06:19

Er, you wrote pretty much exactly what chimpy did, only more long winded, I'm afraid. You got a max velocity of ~0.58c while he got one of ~0.57c and considering how imprecise the original data is that's well within any margin of error. The figures themselves do not look too implausible on the surface but they aren't much practical use as anything other than a rough guide, unfortunately. The usual limiting factor is power output of the propulsion system, and that even assuming a newtonian system (rather than a relatavistic one, where the situation is even worse) any doubling of speed requires quadrupling an object's kinetic energy.

By quick calculation* to accelerate an object to 0.58c and back over forty years you'd need an average of ~23 megawatts/kg of energy supplied (each and every second for forty years, and considerably more towards the upper speed range assuming linear acceleration) over the full forty years, or in other words it would take every joule from four decent sized (~400MW) current power stations over forty years to move an average man that far that fast. 23 gigawatts to move 1 cubic meter of water. Every nuclear power plant on the planet would be needed to provide the energy to move a 12t object that far that fast. Using wikipedia's figures, every bit of electricity generated on the planet at present would only move something around 125t that far that fast. I'd suggest that it's highly unlikely that a grove can provide that level of power, especially since we'd have to presume that the vast majority of Citadel's power came from the Reactor, or indeed that a grove weighs anything less than several thousand tonnes at a bare minimum.

And that's ignoring the fact that running into just about anything at those sort of speeds would almost inevitably result in a total disaster.

*using e (total) =mv^2 where v(max)=1.71x10^8 ms-1 and it is assumed that all energy for acceleration and deceleration comes from an internal source, and the energy is supplied constantly over the whole 1.26x10^9 s.

rachel on 27/5/2008 at 09:18

I've thought about it a bit and I think my example was the explanation given in Event Horizon to explain wormholes to the crew. Bending space is not sufficient, the connection is provided by the wormhole, like the pin ripping through the paper to connect the two dots together.

That's how I remember it anyway.

Star Trek and Shock 2, iirc, used the bubble FTL thing as NV said. I don't really remember the specifics however...

RocketMan on 27/5/2008 at 17:12

Yeah you're right that did come from Event Horizon now that I think about it. The way Dr. Wier explained the black hole thing though was IMO inaccurate. His paper example implied bringing point A and B towards eachother and then making a small rip to traverse the remaining gap between them. I think he even said "fold space-time so that A and B coexist"...something something. Traditional black hole wormholes do not require any folding or shortening of the space between A and B. What I mean is, the space between A and B does not need to be affected at all. The new path leaves all other paths unchanged. Since the universe is a 3D "surface" in 4D space, bridging huge gaps is topologically simpler than it would seem due to our inability to visualize enough dimensions to see what's actually happening.

If we were to modify his paper example so that it was more accurate, then we wouldn't fold the paper at all. Instead what we'd do is punch a hole through A with a long, bendy pencil, push it through and curve it towards B and then punch through B. The only thing is that the length of the pencil should still be much much shorter than the distance from A to B on the paper (though if you did this without folding the paper there's no way it could be shorter...yet this is how it works in 4D)

Nameless Voice on 27/5/2008 at 17:16

But folding a piece of paper does not change the distance between two points when travelling across the surface of the paper.

rachel on 27/5/2008 at 17:43

Exactly. It's like crossing a bridge across the grand canyon instead of hiking all the way down and then all the way up.