Keep the great information coming Prim...and thanks! Anyone know if there are some good books out there that discuss the basic points covered in this thread - I mean in a relatively non-technical way?
There is a book at Amazon that interests me...although as far as I can tell it is much more about cosmological theory than space travel. But I think we'll find the two are inextricably linked. We're going to have to understand cosmology at a higher level before we'll ever be able to travel to any of these places we see from the HST - let alone colonize there.
All this takes a very long time with conventional manner of production (particle accelerators). Production of 100 g of antimatter would take hundreds of centuries to complete, almost as long as the completion of the PowerPC 8500.
Second point the storage of antimatter in christal.
The christal have to be in a special matter : you need Dilithium christals.
Unless the antimatter is the means of propulsion... but I can't think of a way that it would be so yes it would take more energy to 'make' antimatter than what antimatter produces. The best reason to use antimatter as an enery producer is the fact that it has a huge mass/energy ratio.
Thanks outsider. At first I thought you were pulling my leg with that title, but it looks interesting. I'm going to do a search on Amazon for "Space Travel" and see what results....
The christal have to be in a special matter : you need Dilithium christals.</strong><hr></blockquote>
Yes, mister powerdoc. Warp Factor 10 !
I will emphasize "conventional" manners of propulsion first (the antimatter is one of these). The unconventional manners are what imply others unproved "exotic" propulsions, like space-time distortion, antigravity or use of other ways than our space-time in our own universe to travel.
The main problem that arises in this dicussion concerns the size of the spaceship and the power of its propulsion. In other words, as Outsider has stated, its mass/energy ratio.
If you want to propel an interplanetary rocket with chemical liquid propergol thrusters (cryogenic H2-02) it must be huge and it will be (relatively) low. 95% of its size will be reserved for the motor. 6 to 10 months in space to reach Mars with 3 or 4 colleagues in a 2x3 meters kitchen-bed-bathroom on the ship's noze...
And you could not indefinitely increase the propellers size because of the total mass. For example, in a powder rocket, you reach ~ 2000 m/s in output. You cannot easily pass this point because in order to increase output velocity by 20%, you must double the powder mass. You see the problem ?
Well, you could then make a ship propelled by H-bombs. It will be faster. But it will be enormous !
The best mass/energy ratio is antimatter, but I repeat it : you should never concentrate such an amount of antimatter in the same place ! Do you want to destruct a whole planet ?
Another, 'conventional', but safer and efficient enough manner of propulsion is to use electricity for plasma thrusters (MPD thrusters). You must have much electricity. What kind of generator then ? Nuclear fission is possible, but controled fusion is better. But do you want to reiterate the big 'chemical' ship design and make a huge tokamak fusion motor (if it proves to work some day...)
IMO the best way to go is : a little hydrogen fusion motor with fusion reactions initiated by little quantities of antimatter, thus allowing a generator with a compact design, and a great mass/energy ratio. It is way safer than H-bombs and antimatter-only, and much quicker than chemical propellers.
[quote]Originally posted by Outsider:<strong>
In order for your neutron engine to work you would need to create neutrons on the fly also. Neutrons are not as stabe as electrons and protons. Unless they are bound in an atomic nucleus the decay after 11 minutes or so.</strong><hr></blockquote>
Yes Outsider, neutron decay is a problem, but I didn't especially talk about a 'neutron motor', whatever atom would work. You could take hydogen, which has one neutron and one electron for its main isotop. No decay ! You concentrate enough power in a little layer of hydrogen, either with a magnetically focused H-bomb, or simpler, with powerful lasers.
The laser system is a real problem because, alas for the moment, we do not know how to make multiterawatts lasers or gamma-ray lasers (grasers), which would collapse the neutrons in the hydogen layer !
We just try to achieve fusion reactions with 1 or 2 TW of power, then for now don't even think about 100 TW to make antimatter by nuclei compression !
[quote]Originally posted by Outsider:<strong>
But I'm not sure I understand how ultra-dense matter can help in space travel. Would it be used to bend space-time? Or as some type of fuel? Thanks for your insight on the subject!</strong><hr></blockquote>
Yes, you're right ! I have just answered your second point (the fuel part) : make ultra-dense matter during a few milliseconds in order to make antimatter, and store some of it in cristals, and use them to initiate fusion reactions in a very compact tokamak.
But your point about bending space-time would be a lot more important in fact... because the processus of neutron collapsing in ultra-dense matter is no less than recreating the moment when a neutron star implodes... and tears the space-time.
I will talk about this possible "unconventional" way of propulsion in my next post, because you're right along my thought !
Cool. I read an old paper once about an unconventional space travel method that would use a condensed ball of matter in front of the ship. Depending on the spin axis and shape of the ball it should create an imperfect warped space bubble that would suck the ship into the bubble. Right before the ship makes contact with the ultra dence matter, it would have to somehoe dissapate the matter either by counter balancing the spin or just releasing the electromagnetic hold it has of the matter (the dence matter would have to have an artificial way to keep its ultra dense state; electromagnatism is much more powerful than gravity and we can easily control electromagnetic fields).When the ship is in the bubble just before it re-expands, the little space it covers is in effect in the outer universe a vast distance.
Magnetoplasmadynamic (MPD) and similar pulsed inductive thrusters (PIT) are nice, but I don't see them going into manned missions. When you have systems with such low thurst and acceleration, a lot of trade-offs are made in terms of mission planning. We must make use of time consuming gravitational assists for acceleration, and wait for windows of launch where conditions are ideal to make use of these gravitational assists. In many cases, a system with higher thrust but lower specific efficiency can reach destinations quicker.
For the near-term, I see great potential in Nuclear Thermal Propulsion. It's specific impulse is twice that of the most efficient chemical rockets and there's already substantial research invested into it. Researchers have recently developed bimodial nuclear reactors for NTP that can still give a specific impulse of 900 with additional benefits. The heat generated by the reactor works some helium-xenon fluid to drive a turbine generator and at the same time, a fractional part of this generated electrical energy is used drive a refrigeration system to keep the liquid hydrogen and reactor parts cool.
Looking 30 years ahead, I can see Variable Specific Impulse Magnetoplasma Rockets (VASIMR) come in. It offers many benefits over NTP namely its high degree of manipulation of the exhaust speed and rate and its astounding efficiencies at low thurst modes. You can find more information about VASIMR <a href="http://spacsun.rice.edu/aspl/vasimr.htm"; target="_blank">here.</a>
Once we develop manned flights that can sustain a relatively high speed and possible introduce some for of artificial gravity for long excursions (centrifugal induced gravity; no star trek technology here) we can start mining the gas giants for hydrogen for spaceship fuel and also for fuel back on earth. One of the biggest problems with getting off gasoline as a primary fuel is of course the alternatives are not as convenient and long range. Bottled hydrogen would solve this (containers will have to be made that wouldn't let so much hydrogen escape from the container walls first but this is just an engineering problem).
Also think about the economic and political aspects of space travel. It'll introduce a completely new economy and cash flow. Millions of Jobs will be made. Who would have jurisdiction in space? One problem i forsee is it will make the Super power nations even more powerful but how can you control a colony millions of miles of way? How you you guys feel about a space colony independent of Earth government, in effect another 'country'. Kind of makes you think we have some more growing up to do or it might get ugly.
<strong>Once we develop manned flights that can sustain a relatively high speed and possible introduce some for of artificial gravity for long excursions (centrifugal induced gravity; no star trek technology here) we can start mining the gas giants for hydrogen for spaceship fuel and also for fuel back on earth. One of the biggest problems with getting off gasoline as a primary fuel is of course the alternatives are not as convenient and long range. Bottled hydrogen would solve this (containers will have to be made that wouldn't let so much hydrogen escape from the container walls first but this is just an engineering problem).
Also think about the economic and political aspects of space travel. It'll introduce a completely new economy and cash flow. Millions of Jobs will be made. Who would have jurisdiction in space? One problem i forsee is it will make the Super power nations even more powerful but how can you control a colony millions of miles of way? How you you guys feel about a space colony independent of Earth government, in effect another 'country'. Kind of makes you think we have some more growing up to do or it might get ugly.</strong><hr></blockquote>
I see a much more bleak future. As we approach the middle of the 21st century, the population of this planet will have swelled to past 14-16 billion. Many of the Earth's natural resources shall have been exhausted. The forests, the oceans, and the atmosphere will all bare the foul aftereffects of human interference. The world's food and mineral resource supply will be in paucity. Standards of living shall decline. Massive bouts of human suffering along with disasters such as global starvation shall cause instabilities in government. Would a world such as this, where the concern is a matter of survival, waste and export valuable resources into space for the "betterment of human kind"?
A new book called the Future of Life highlights my concerns. You can get a brief idea by reading the following Scientific American article.
We need to evolve our behaviour because I definately know that's what you meant (biological evolution would obviously take millions of more years that we really have). Sadly many people don't see the benefits of long term research and development of technology that will make the life of our children and their offspring easier to bear. I think independent organizations will be the first to make extra terrestrial space colonies... they better. i f we leave it up to the government we'll be waiting for a long time.
We are talking about interplanetary propulsions, inside our solar system. But it is excluded to reach stars with these kind of propulsions, unless we don't mind to travel for centuries. We must find "another way".
Making a ship "as fast as ligh" is impossible because its mass would reach infinity. So the power to propel it would also be infinite.
"Faster-than-light" is a physical nonsense because the power would be beyond an infinite value, and the mass of the ship would become negative (imaginary number). I don't even talk about time which goes backward... It is another subject which would fill a ton of pages like this.
Even propelling a ship to 20 or 50 % of c (light celerity) would be very difficult cause of the energy spent for pushing such a big mass.
Some talks about "antigravity" to propel a ship. Others talks about bending space-time with enough gravity or energy (they are the same) to attract the ship/decrease distances between start and end points/make it appearing "faster-than-light".
Others talks about "tearing space-time" and "crossing the floor of our universe". We would find ourselves at the "downstairs neighboor". This theory imply paths shorter than the straight line, because the universe is bent and the "straight line" we see is only the path whom the light borrows (geodesics).
The "real straigh line" would be much shorter between stars :
Two theories clash here :
1- The first, more an idea than a theory, if from astrophysicists like Kip Thorne. It is the "wormhole": you create an ultra-dense matter state in one point which creates "a black hole". You are aspired in this wormhole input, then you arise immediately out of a "white fountain", at another place in the Universe. A sort of stargate with random destination...
But the <a href="http://www.jp-petit.com/Extensions/pres_questionable_en/PQ1trad.htm"; target="_blank">black hole sucks</a> for mathematical reasons. Moreover the "wormhole" would be very unstable and retract itself, closing the indoor and the outdoor too quickly to be able to pass the gate. Kip Thorne suggests stabilizing the wormhole by throwing "magnetic monopoles" in it. But the problem is... that no scientist has never heard of such "magnetic monopoles" !
2- The second theory, more and more documented, is the "multi-universe" theory, from astrophysicists like Andeï Sakharov or Jean-Pierre Petit (see the <a href="http://www.jp-petit.com/science/interstellar_travel/interstellar_travel1bis.htm"; target="_blank">Twin Universes Cosmological model and its applied interstellar travel</a>).
Universe would not be "unic", or more exactly it would not have "only one face', there would rather coexist various "layers". The layers could not communicate directly (you don't see the twin-universe) because they don't share all their dimensions. But they share the same Universe, they are complementary. Light cannot go accross two layers, but gravitationnal waves do. All is inverted in the twin-universe (the CPT symetry I spoke before).
- Our universe is made of matter condensed in planets, stars, galaxies, and it is relatively old and well expanded...
- The twin-universe contains antimatter and its time arrow is inverted from our point of view. Thus It would be younger, like ours at the beginning. No galaxies, no stars, no planets. Only gaz nebulas. It would also be less expanded, more concentrated. Thus the speed of light would be much greater than "our" speed of light (in "variable constants" cosmological models, where all the "constants" would vary together along the diameter of the universe). Distances would be also much shorter.
In consequence, if one could dive and travel into this twin-universe, its ship could go faster and the distance to cover would be shorter. Then he would just reappear in our "layer".
Do you beleive in tachyons? Perhaps if there was a way to harness their energy (since they are faster than light particle they should have negative mass and therefore negative energy) to 'neutralize' a ship so it can slip through space time on a level that would allow you to exceed the speed of light. But would a time paradox prevent this from happening? Are we prohibited from travelling at the speed of light or faster in this universe forever?
Wasnt there a guy who managed to accelerate light to something like 600x the speed of light? If you could turn matter into energy and energy into light (how?) then use this system space travel would be SHORT!
The problem of course is that youd need to build a tunnel of some sorts to carry this light, and THAT would be hard. Somehting to do with the fact that that the solar system turns and any sort of pipeline would be completley uselss/wrecked.
Of course I suppose some sort of intersteller highway could work, dropping you at points which would be closer to your target.
As for antimatter, the other problem with particle accellerators is the possibillity of strangelets
In regards to time paradoxes...My friend read a book(I think it was in a book) that was talking about how "bill and ted" movies are actually 100% correct(back to the future is actually more incorrect)
well my friend(who is a pretty smart guy...he also knows ALOT about what we're talkign about in this thread)thinks he has proven that he will never travel in time....how? given "bill and ted" is 100% plausible, then if you were going to travel into the past or likewise than if you simply say "when I travel back I will remember to have put a bowl of soup on my desk at 9:10 PM febuary 15th 2002" and if a bowl of soup appears on your desk..then that means that you WILL travel in time sometime before you die
Have you guys ever heard of Generation Ships? Or how about Space Arks? They are an engineering nightmare. Basically they are huge ships that people live on for many many years. I'm talking about multiple lifetimes. One plan is to make a huge sealed and hollow cylinder about 2 miles long and 1 mile in diameter. That gives you about 6.28 square miles of surface area on the inside of the cylinder. Now on the outside of the cylinder you mount some ionic engines that would make the whole cylinder rotate on the axis right through the center. This would cause an artificial gravity using centrifugal forces that can be modified by speeding up the engines or slowing them down to create about 1G of gravity on the inner surface of the cylinder. Now you would need foward propulsion and you would need a nuclear engine (fusion since there would be no problem in getting hydrogen as fuel in the vastness of space; just use a ion ram scoop) affixed to the rear of the huge cylinder. For directional steering you can have non-rotating steering thrusters mounted on a pod protruding from the front that are mounted on an axis held onto the front with electro-magnetism. To counter balance the rotational torque, you can use 2 1-mile long cylinders and have them rotate on opposite directions.
On the inside of the cylinder you would fill it with dwellings and factories and infrastrucure facilities for people to live and work in. People will get married start families (one child max to limit the population and any deaths will open up a pass for a family to have one kid. this will ensure the population of the ark never exceeds the capacity) and die while on route to a distand solar system to see if they can inhabit it. One section of the ark will need to house plants and a small forest. This is to provide food, water and oxygen for the inhabitants. Everything will need to be recycled; urine, waste, dead bodies, garbage, etc. Interstellar ice can be collected as can mineral rick asteroids to be used for construction.
While on the ship people will be working on plans for terraformation factories to be placed on suitable planets for future generations. When such a planet is found the ark can go into obit around the planet and work from orbit. Terraformation takes hundreds if not thousands of years but gradually in their lifetimes they can set up temporary enclosed colonies on the surface as the population in the ark gets bigger.
Comments
There is a book at Amazon that interests me...although as far as I can tell it is much more about cosmological theory than space travel. But I think we'll find the two are inextricably linked. We're going to have to understand cosmology at a higher level before we'll ever be able to travel to any of these places we see from the HST - let alone colonize there.
<a href="http://www.amazon.com/exec/obidos/ASIN/0375708111/qid=1013200554/sr=2-2/ref=sr_2_2/002-0297069-8333661"; target="_blank">http://www.amazon.com/exec/obidos/ASIN/0375708111/qid=1013200554/sr=2-2/ref=sr_2_2/002-0297069-8333661</a>;
first point ;
All this takes a very long time with conventional manner of production (particle accelerators). Production of 100 g of antimatter would take hundreds of centuries to complete, almost as long as the completion of the PowerPC 8500.
Second point the storage of antimatter in christal.
The christal have to be in a special matter : you need Dilithium christals.
Moogs, I have the perfect book for you. it's exactly what you are looking for. The Star Flight handbook. <a href="http://www.amazon.com/exec/obidos/ASIN/0471619124/qid=1013204125/ref=sr_11_0_1/102-4207012-1358515" target="_blank">http://www.amazon.com/exec/obidos/ASIN/0471619124/qid=1013204125/ref=sr_11_0_1/102-4207012-1358515</a>
The christal have to be in a special matter : you need Dilithium christals.</strong><hr></blockquote>
Yes, mister powerdoc. Warp Factor 10 !
I will emphasize "conventional" manners of propulsion first (the antimatter is one of these). The unconventional manners are what imply others unproved "exotic" propulsions, like space-time distortion, antigravity or use of other ways than our space-time in our own universe to travel.
The main problem that arises in this dicussion concerns the size of the spaceship and the power of its propulsion. In other words, as Outsider has stated, its mass/energy ratio.
If you want to propel an interplanetary rocket with chemical liquid propergol thrusters (cryogenic H2-02) it must be huge and it will be (relatively) low. 95% of its size will be reserved for the motor. 6 to 10 months in space to reach Mars with 3 or 4 colleagues in a 2x3 meters kitchen-bed-bathroom on the ship's noze...
And you could not indefinitely increase the propellers size because of the total mass. For example, in a powder rocket, you reach ~ 2000 m/s in output. You cannot easily pass this point because in order to increase output velocity by 20%, you must double the powder mass. You see the problem ?
Well, you could then make a ship propelled by H-bombs. It will be faster. But it will be enormous !
The best mass/energy ratio is antimatter, but I repeat it : you should never concentrate such an amount of antimatter in the same place ! Do you want to destruct a whole planet ?
Another, 'conventional', but safer and efficient enough manner of propulsion is to use electricity for plasma thrusters (MPD thrusters). You must have much electricity. What kind of generator then ? Nuclear fission is possible, but controled fusion is better. But do you want to reiterate the big 'chemical' ship design and make a huge tokamak fusion motor (if it proves to work some day...)
IMO the best way to go is : a little hydrogen fusion motor with fusion reactions initiated by little quantities of antimatter, thus allowing a generator with a compact design, and a great mass/energy ratio. It is way safer than H-bombs and antimatter-only, and much quicker than chemical propellers.
[quote]Originally posted by Outsider:<strong>
In order for your neutron engine to work you would need to create neutrons on the fly also. Neutrons are not as stabe as electrons and protons. Unless they are bound in an atomic nucleus the decay after 11 minutes or so.</strong><hr></blockquote>
Yes Outsider, neutron decay is a problem, but I didn't especially talk about a 'neutron motor', whatever atom would work. You could take hydogen, which has one neutron and one electron for its main isotop. No decay ! You concentrate enough power in a little layer of hydrogen, either with a magnetically focused H-bomb, or simpler, with powerful lasers.
The laser system is a real problem because, alas for the moment, we do not know how to make multiterawatts lasers or gamma-ray lasers (grasers), which would collapse the neutrons in the hydogen layer !
We just try to achieve fusion reactions with 1 or 2 TW of power, then for now don't even think about 100 TW to make antimatter by nuclei compression !
[quote]Originally posted by Outsider:<strong>
But I'm not sure I understand how ultra-dense matter can help in space travel. Would it be used to bend space-time? Or as some type of fuel? Thanks for your insight on the subject!</strong><hr></blockquote>
Yes, you're right !
But your point about bending space-time would be a lot more important in fact... because the processus of neutron collapsing in ultra-dense matter is no less than recreating the moment when a neutron star implodes... and tears the space-time.
I will talk about this possible "unconventional" way of propulsion in my next post, because you're right along my thought !
[ 02-10-2002: Message edited by: Prim ]</p>
For the near-term, I see great potential in Nuclear Thermal Propulsion. It's specific impulse is twice that of the most efficient chemical rockets and there's already substantial research invested into it. Researchers have recently developed bimodial nuclear reactors for NTP that can still give a specific impulse of 900 with additional benefits. The heat generated by the reactor works some helium-xenon fluid to drive a turbine generator and at the same time, a fractional part of this generated electrical energy is used drive a refrigeration system to keep the liquid hydrogen and reactor parts cool.
Looking 30 years ahead, I can see Variable Specific Impulse Magnetoplasma Rockets (VASIMR) come in. It offers many benefits over NTP namely its high degree of manipulation of the exhaust speed and rate and its astounding efficiencies at low thurst modes. You can find more information about VASIMR <a href="http://spacsun.rice.edu/aspl/vasimr.htm"; target="_blank">here.</a>
[ 02-11-2002: Message edited by: Nostradamus ]</p>
Also think about the economic and political aspects of space travel. It'll introduce a completely new economy and cash flow. Millions of Jobs will be made. Who would have jurisdiction in space? One problem i forsee is it will make the Super power nations even more powerful but how can you control a colony millions of miles of way? How you you guys feel about a space colony independent of Earth government, in effect another 'country'. Kind of makes you think we have some more growing up to do or it might get ugly.
<strong>Once we develop manned flights that can sustain a relatively high speed and possible introduce some for of artificial gravity for long excursions (centrifugal induced gravity; no star trek technology here) we can start mining the gas giants for hydrogen for spaceship fuel and also for fuel back on earth. One of the biggest problems with getting off gasoline as a primary fuel is of course the alternatives are not as convenient and long range. Bottled hydrogen would solve this (containers will have to be made that wouldn't let so much hydrogen escape from the container walls first but this is just an engineering problem).
Also think about the economic and political aspects of space travel. It'll introduce a completely new economy and cash flow. Millions of Jobs will be made. Who would have jurisdiction in space? One problem i forsee is it will make the Super power nations even more powerful but how can you control a colony millions of miles of way? How you you guys feel about a space colony independent of Earth government, in effect another 'country'. Kind of makes you think we have some more growing up to do or it might get ugly.</strong><hr></blockquote>
I see a much more bleak future. As we approach the middle of the 21st century, the population of this planet will have swelled to past 14-16 billion. Many of the Earth's natural resources shall have been exhausted. The forests, the oceans, and the atmosphere will all bare the foul aftereffects of human interference. The world's food and mineral resource supply will be in paucity. Standards of living shall decline. Massive bouts of human suffering along with disasters such as global starvation shall cause instabilities in government. Would a world such as this, where the concern is a matter of survival, waste and export valuable resources into space for the "betterment of human kind"?
A new book called the Future of Life highlights my concerns. You can get a brief idea by reading the following Scientific American article.
<a href="http://www.sciam.com/2002/0202issue/0202wilson.html"; target="_blank">http://www.sciam.com/2002/0202issue/0202wilson.html</a>;
The human race must evolve or suffocate to extinction along with countless species on our planet Earth.
[ 02-11-2002: Message edited by: Nostradamus ]</p>
Making a ship "as fast as ligh" is impossible because its mass would reach infinity. So the power to propel it would also be infinite.
"Faster-than-light" is a physical nonsense because the power would be beyond an infinite value, and the mass of the ship would become negative (imaginary number). I don't even talk about time which goes backward... It is another subject which would fill a ton of pages like this.
Even propelling a ship to 20 or 50 % of c (light celerity) would be very difficult cause of the energy spent for pushing such a big mass.
Some talks about "antigravity" to propel a ship. Others talks about bending space-time with enough gravity or energy (they are the same) to attract the ship/decrease distances between start and end points/make it appearing "faster-than-light".
Others talks about "tearing space-time" and "crossing the floor of our universe". We would find ourselves at the "downstairs neighboor". This theory imply paths shorter than the straight line, because the universe is bent and the "straight line" we see is only the path whom the light borrows (geodesics).
The "real straigh line" would be much shorter between stars :
Two theories clash here :
1- The first, more an idea than a theory, if from astrophysicists like Kip Thorne. It is the "wormhole": you create an ultra-dense matter state in one point which creates "a black hole". You are aspired in this wormhole input, then you arise immediately out of a "white fountain", at another place in the Universe. A sort of stargate with random destination...
But the <a href="http://www.jp-petit.com/Extensions/pres_questionable_en/PQ1trad.htm"; target="_blank">black hole sucks</a>
2- The second theory, more and more documented, is the "multi-universe" theory, from astrophysicists like Andeï Sakharov or Jean-Pierre Petit (see the <a href="http://www.jp-petit.com/science/interstellar_travel/interstellar_travel1bis.htm"; target="_blank">Twin Universes Cosmological model and its applied interstellar travel</a>).
Universe would not be "unic", or more exactly it would not have "only one face', there would rather coexist various "layers". The layers could not communicate directly (you don't see the twin-universe) because they don't share all their dimensions. But they share the same Universe, they are complementary. Light cannot go accross two layers, but gravitationnal waves do. All is inverted in the twin-universe (the CPT symetry I spoke before).
- Our universe is made of matter condensed in planets, stars, galaxies, and it is relatively old and well expanded...
- The twin-universe contains antimatter and its time arrow is inverted from our point of view. Thus It would be younger, like ours at the beginning. No galaxies, no stars, no planets. Only gaz nebulas. It would also be less expanded, more concentrated. Thus the speed of light would be much greater than "our" speed of light (in "variable constants" cosmological models, where all the "constants" would vary together along the diameter of the universe). Distances would be also much shorter.
In consequence, if one could dive and travel into this twin-universe, its ship could go faster and the distance to cover would be shorter. Then he would just reappear in our "layer".
... How to dive ?
[ 02-14-2002: Message edited by: Prim ]</p>
Well, I know Im gonna get shot down here but...
Wasnt there a guy who managed to accelerate light to something like 600x the speed of light? If you could turn matter into energy and energy into light (how?) then use this system space travel would be SHORT!
The problem of course is that youd need to build a tunnel of some sorts to carry this light, and THAT would be hard. Somehting to do with the fact that that the solar system turns and any sort of pipeline would be completley uselss/wrecked.
Of course I suppose some sort of intersteller highway could work, dropping you at points which would be closer to your target.
As for antimatter, the other problem with particle accellerators is the possibillity of strangelets
'couse thats SUCH a small possibillity.
well my friend(who is a pretty smart guy...he also knows ALOT about what we're talkign about in this thread)thinks he has proven that he will never travel in time....how? given "bill and ted" is 100% plausible, then if you were going to travel into the past or likewise than if you simply say "when I travel back I will remember to have put a bowl of soup on my desk at 9:10 PM febuary 15th 2002" and if a bowl of soup appears on your desk..then that means that you WILL travel in time sometime before you die
what do you think?
I LOVE this thread! keep it alive please!
Have you guys ever heard of Generation Ships? Or how about Space Arks? They are an engineering nightmare. Basically they are huge ships that people live on for many many years. I'm talking about multiple lifetimes. One plan is to make a huge sealed and hollow cylinder about 2 miles long and 1 mile in diameter. That gives you about 6.28 square miles of surface area on the inside of the cylinder. Now on the outside of the cylinder you mount some ionic engines that would make the whole cylinder rotate on the axis right through the center. This would cause an artificial gravity using centrifugal forces that can be modified by speeding up the engines or slowing them down to create about 1G of gravity on the inner surface of the cylinder. Now you would need foward propulsion and you would need a nuclear engine (fusion since there would be no problem in getting hydrogen as fuel in the vastness of space; just use a ion ram scoop) affixed to the rear of the huge cylinder. For directional steering you can have non-rotating steering thrusters mounted on a pod protruding from the front that are mounted on an axis held onto the front with electro-magnetism. To counter balance the rotational torque, you can use 2 1-mile long cylinders and have them rotate on opposite directions.
On the inside of the cylinder you would fill it with dwellings and factories and infrastrucure facilities for people to live and work in. People will get married start families (one child max to limit the population and any deaths will open up a pass for a family to have one kid. this will ensure the population of the ark never exceeds the capacity) and die while on route to a distand solar system to see if they can inhabit it. One section of the ark will need to house plants and a small forest. This is to provide food, water and oxygen for the inhabitants. Everything will need to be recycled; urine, waste, dead bodies, garbage, etc. Interstellar ice can be collected as can mineral rick asteroids to be used for construction.
While on the ship people will be working on plans for terraformation factories to be placed on suitable planets for future generations. When such a planet is found the ark can go into obit around the planet and work from orbit. Terraformation takes hundreds if not thousands of years but gradually in their lifetimes they can set up temporary enclosed colonies on the surface as the population in the ark gets bigger.
E^2=(pc)^2+(m_0c^2)^2
If you have m_0 < 0 then m_0^2 is > 0 and E is >0
m_0 = rest mass
Is it {rest-mass * (c^2)} or {(rest-mass * c)^2}.
Thanks for pointing that out. I think the whole idea baout negative mass is still under debate and some equations are not adding up while others are.
If you start out with E^2 on one side of the equation the it doesn't mater is the energy (E) is negative or positive.
E^2 = -E * -E = E * E
Same goes for rest mass. It all gets treated as positive when you square it anyways.