Space Travel Propulsion.

[NYSEF816]

Spock started this on AF, and it was a lively discussion, hopefully it can become one here too.

any theories, ideas, etc? the craziest idea you can think of, especially concerning FTL travel, is probably most likely...

[R-D-A]

FTL?? Thats gonna be hard. Only by altering the Mass..like in mass effect

[Human No More]

The main solution to FTL is to actually travel slower than light, but not linearly in normal space (e.g. wormholes), so you just end up much further away than the distance it took to travel in normal space terms.

[Jamza]

I know star trek style teleportation seems confined to the realms of science fiction, but I still think it could hold some yields and could make propulsion unnecessary. Yes, its improbable, but not impossible.

I like the idea we can currently teleport one molecule, thats one small step to the billions that exist within me

[Human No More]

Well, warp travel is certainly theoretically possible - it relies on subspace, the main principle is that a ship in warp is not actually in normal space, and subspace is related to distances differently (like folding a piece of paper, if that paper was 3D space).
Transporters aren't quite so possible simply due to the energy requirements (also, the amount of memory that would be needed, although saying anything is impossible due to memory limits will generally just make you look stupid in 10 years, with the rate of improvement )

[NYSEF816]

Originally Posted by Human No More

(also, the amount of memory that would be needed, although saying anything is impossible due to memory limits will generally just make you look stupid in 10 years, with the rate of improvement )

i read somewhere that to transport a human, it would take enough CD-ROMs (80mb) to go from earth, to the sun and back 8 times! maybe one day, but as of right now it isnt even worth making a thread over.

FTL propulsion, as human no more pointed out, isnt so much the craft moving faster then light, but the space around it. 2 theories like this, warp drive and hyper-drive (slip-space) manipulate the space around the spaceship. warp drive, in short, rides a 4 dimensional 'wave' created in space-time fabric that allows it to travel at FTL speeds without violating the laws of relativity. Hyper-space is traveling in the higher dimensions theorized by string theory, literally traveling in 'the space between space', and has a very similar theory to wormhole travel.

The only FTL method where a ship actually travels FTL, and is therefore (if not impossible) centuries away from a distinct possibility, is harnessing tachyon rays in a forcefield around a craft to allow it to travel FTL (actually, if using tachyons, you could travel anywhere in the universe instantaneously). my PhD thesis is on tachyons, i have done extensive research on them.... and i would adivse everyone here not to get your hopes up not for a few centuries.

[Human No More]

The main problem with tachyons is IIRC, that they don't interact with normal matter at all

[NYSEF816]

Originally Posted by Human No More

The main problem with tachyons is IIRC, that they don't interact with normal matter at all

precisely. and since they only travel FTL, it would be completely impossible for us to see them with any technology either since they are not within any spectrum. my thesis so far is "tachyons are cool.... i think.... i havent seen them, but here are some long equations.... please pass me!"

[Gunny]

We need to figure out how to go plaid!!!

[R-D-A]

I still think that when sth accelerates in such speeds...it creates a gravitational field. This field in such speeds would kill us. A simple fall would make someone one with the floor...literally.

[Spock]

This should help, its straight out of my thread over in A.F.

Heres a post that sums up some forms of space travel propulsion, whether they be faster than light or not. I will provide links as well. But for those who don't want to troll through the links, I will provide an acompanying summary.

Basic rocket: http://en.wikipedia.org/wiki/Rocket

The modern rocket baisically works by reacting a propellant with an oxidizer propellant this produces very hot gases that expand and rush out the rocket nozzles at hypersonic speeds and thus propelling the rocket forward.

Rockets have been around since the 1200's, first originating in China, the technology was subsequently spread by Ghengis Khan during his conquest of China and Transoxania. Rocket technology was stagnant up until Konstantin Tsiolkovsky proposed using liquid hydrogen and oxygen as a propellant, thus the birth of the modern rocket. Rockets are still widely used in the aerospace industry making them a 800 year old technology. Time to move on perhaps?

Ion drive: http://en.wikipedia.org/wiki/Ion_drive

Ion drives are perhaps the most efficient form of space travel technology to date, as a very high propellant efficiency is attained.

So, how do they work: Please see link.

Dr. Robert H Godard first proposed the theory in 1906. But it wasn't until the 1960's that sub-orbital tests were conducted. Currently they are used in deep space probes and as small "Hall" thrusters to stabilize satellites in orbit.

Alcubierre drive: http://en.wikipedia.org/wiki/Alcubierre_drive

I believe that this is our best hope of inter-stellar travel. It is a reminscent of the popular "Warp drive" in the Star Trek series.

This baisically works by having the space in front of the ship contract, and then expand behind it, the ship will not be actually moving but rather moving with the region of space as it moves. Remember space moves, time doesn't.

This theory was proposed by a mexican physicist Miguel Alcubierre, but the theory will remain as such as there is no known way of creating a warp bubble around a ship. There are signifigant difficulties for this theory to overcome before it become practical, please see the link.

Solar sails: http://en.wikipedia.org/wiki/Solar_sail

This method of propulsion requires large sails to be extended behind a ship, maybe even tens or hundreds of kilometres wide, so that photons from a star, or a laser can push the ship along.

This method seems impractical to me, because it will take many years for ships to reach realistic speeds for interstellar travel, thus creating the need for multi-generational ships etc.

Antimatter/Matter reaction rocket: http://en.wikipedia.org/wiki/Antimatter_rocket

This is another method that I find hope in, it won't be effective for interstellar travel, but it could make traveling around our own solar system almost easy. This could in theory propell a ship up to 100,000 kilometres a second. This is what the ISV Star Venture used in conjunction with fusion engines.

Well, how does it work? Put simply it just means anhilating anti-protons with protons, resulting in a near 100% conversion of matter to energy, very efficient considering fusion reactions are only 2%. The main problem this method faces is that manufacturing the anti-matter on a scale needed is unpractical at the present time. In a 1 month trip to mars it would take 10 grams of anti-matter. I don't even think 10 grams has ever been produced if you add up all the anti-matter that has currently come into existence due to the use of Ion colliders.

Project Orion: http://en.wikipedia.org/wiki/Project...ar_propulsion)

I think this one has pretty much been covered but here we go anyway, during 1947 the idea was proposed by Stanisław Ulam, his vision was realised by 1958 when experimentation commenced.

How this worked was the explosion of atomic bombs behind the spacecraft, the craft would then be propelled forward by the force of the shockwave created by the bombs. The project was scrapped in 1963 with the ban on atmospheric nuclear testing.

Nuclear photonic rocket: http://en.wikipedia.org/wiki/Nuclear_photonic_rocket

This design relied on a nuclear reactor running at extremely high temperatures, thus creating "blackbody radiation" that provided significant thrust, all the way up to light speed. It is stated that this method is feasible, but not practical with 21st century technology as the energy required is truly immense.

This method is touted to provide thrust that will power the ship up to 240km/s.

There are more theories and methods but to me these ones stood out the most.

Thankyou, live long and prosper.

[Afkeu]

Originally Posted by NYSEF816

precisely. and since they only travel FTL, it would be completely impossible for us to see them with any technology either since they are not within any spectrum. my thesis so far is "tachyons are cool.... i think.... i havent seen them, but here are some long equations.... please pass me!"

LOL! Would you send me a copy of your real thesis when it's done? I am quite interested.

As for FTL, I will try to avoid putting all my eggs in the Warp/Alcubierre Drive basket, but thats where I'm leaning. Unfortunately we run into the problem of needing vast amounts of energy, like the energy of a star almost. However, Perhaps this could be achieved by merging the Warp/Alcubierre Drive and the MAtter/Anit-Matter Drive and using the energy from the annihilation to power the warp drive.
Also, here is a totally crazy idea that I came up with: If the energy of a star is required to power a warp drive, then we could use the energy of the sun and move the entire earth to some new system! We would take the moon with us too because it's gravitational pull causes things like tides. Disclaimer: I Don't really think this is a good idea, it just randomly popped into my head.

[Tsyal Makto]

As for non-FTL travel, I LOVE the idea of Project Orion. I think it's time NASA dust off the plans and at least explore a modernized version. Imagine something built with light-weight materials and built in orbit. The nuclear weapons can be lofted into space and loaded into the pre-built Orion. Detonations can begin once the craft has been pushed out of the magnetosphere with small rockets.

You can kill two birds with one stone - Nuclear disarmament and high speed space travel! The US and Russia were planning to reduce their nuclear arsenal in the coming years, why not put them to good use?

Another interesting high speed, non-FTL idea is the Bussard hydrogen ramjet.

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

[Human No More]

The Bussard ramjet concept is interesting (those are what the parts on the front of nacelles on Star Trek ships are), but from what I understand, it was based on a higher estimate of hydrogen particles than there actually appear to be so probably wouldn't work so well at a speed where it would be useful, unless the magnetic field was huge.

[Afkeu]

Originally Posted by Human No More

The Bussard ramjet concept is interesting (those are what the parts on the front of nacelles on Star Trek ships are), but from what I understand, it was based on a higher estimate of hydrogen particles than there actually appear to be so probably wouldn't work so well at a speed where it would be useful, unless the magnetic field was huge.

That is exactly the problem with that theory, there are not nearly enough random protons flying around. Also, here is a problem with SubFTL travel, even at those speeds something as small as a proton would do "Terrible Terrible Damage" to your spaceship when it collides.

P.S. To anyone who know where that quote is from: LOL