Antimatter - More viable than fusion?

John Creighton · 2005-09-03 17:59:47

Building a ship to reflect the gamma and cosmic-class rays produced by a M/AM reaction around the crew cabin would be impossible, because the higher the energy of the incident ray, the more shallow the angle must be to reflect that ray. At these incredibly high energies, the crew cabin would have to be so pointy, that it would be impossible to engineer such a vessel.

Lets think about this. The pointier the ship is the more materials is in path between the matter antimatter reaction and the crew cabin. Because it will be pointy near the reaction then this portion of the ship will comprise a smaller mass relative to the mass of the ship. Also the point puts distance between the reaction and the crew cabin. So it doesn't have to reflect all the energy produced by the reaction.

publiusr · 2005-09-08 14:23:54

There is something in the new Infinite Energy mag about un-matter--where the neutrons are normal. Odd.
Infinite Energy mag eh? Sounds fishy.

It is--woo-woo stuff.

Less so-perhaps:
http://www.xprizenews.org/forum/viewtopic.php?t=1319

Anti-Matter
http://www.bautforum.com/showthread.php?t=30746

Links:
http://www.bautforum.com/showthread.php?t=22865
http://www.bautforum.com/showthread.php … post551917

GCNRevenger · 2005-09-11 20:04:56

Building a ship to reflect the gamma and cosmic-class rays produced by a M/AM reaction around the crew cabin would be impossible, because the higher the energy of the incident ray, the more shallow the angle must be to reflect that ray. At these incredibly high energies, the crew cabin would have to be so pointy, that it would be impossible to engineer such a vessel.
Lets think about this. The pointier the ship is the more materials is in path between the matter antimatter reaction and the crew cabin. Because it will be pointy near the reaction then this portion of the ship will comprise a smaller mass relative to the mass of the ship. Also the point puts distance between the reaction and the crew cabin. So it doesn't have to reflect all the energy produced by the reaction.

I don't think that you understand, the angle has to be almost zero for there to be ANY reflection. You can't build such a ship, it would be miles and miles long before you would even have enough diameter to stand up.

Josh Cryer · 2005-09-16 09:53:02

Why not just tow the cabin behind the ship at a few hundred miles?

GCNRevenger · 2005-09-16 11:16:19

Right in the ultrahigh energy gamma ray beam from the antimatter malestrom that is pushing your ship?

Swell

John Creighton · 2005-09-16 11:57:55

Why not just tow the cabin behind the ship at a few hundred miles?

Right in the ultrahigh energy gamma ray beam from the antimatter malestrom that is pushing your ship?
Swell

Actually, it is the right solution if it is not practical to push the crew cabin.

I am not sure how much distance you need between the antimatter reactor and the crew cabin and how much material between the reactor and crew cabin will reduce the distance. GCNRevenger thinks it is unpractical to push the crew cabin yet he never gave any number for radiation intensity and transmittance of materials for various types of radiation. With carbon nanotubes extremely long and light cables can be made. If the cabin is being bulled it means that the connecting structure between the reactor and the crew cabin does not have to support any moments. As for putting it in the beam that would be stupid. Fire 3 engines at an angle of 45 degree angle from the cable. This will provide a built in mechanism for steering and any loses of efficiency caused by the angle the engine fires can be made up for by the gigantic specific impule of an anit matter type space ship.

Austin Stanley · 2005-09-27 03:30:32

I don't know about all this. Your solution of dragging the crewed portion behind the engines is inovative, and does have some advantages, such as possibly being able to use the engines as shield from some of the comsic radiation and debris you can encounter when crusing around a signifigant faction of C.

However you lose a serious amount of thrust/efficency and you have to have at least 3 engines instead of one.

---

In the end I think the best solution is what I recomended earlier, just seperate the crew from the engines as much as possible. Any anti-matter/photon engine is going to put out an insignifigant amount of thrust, so putting the crew out on a boom along way from the engine should be that much of a challenge. The hab is going to need some serious radiation shielding just due to the long amounts of time it is going to spend in space, and this should probably be sufficent.

GCRN is also right that for some of the extreamly high energy photon's given off by the engine no shielding tricks or fancy shapes of any reasonable mass are going to impeed these particles. However, if you move far enough away, it won't matter. Enough distance will allow you to doge the majority of them. Yes the crew and hab will still get hit by the high-energy photon, but just one or two of these is not a problem, as they body (and equipment) can adjust and correct whatever ionizing effects it might have.

redhorizons · 2005-09-27 16:40:43

I admit I am a complete lay person here. So offer a question with a suggestion. If instead of pulling the crew quarters directly behind and in line of the thrust and radiation, or in some triangulation of engines that jeopardizes thrust, what about building the crew quarters as donut and pull it behind one engine, allowing the thrust to go through the whole in the middle.??
my question is, would the radiation be dispersed in a jet like the thrust or would it disperse more freely, thus defeating my idea?

Another good reason for the donut is you can spin it nicely to induce artificial-G for the long trips.

Or am I just talking out of my butt?

John Creighton · 2005-09-27 16:47:17

I admit I am a complete lay person here. So offer a question with a suggestion. If instead of pulling the crew quarters directly behind and in line of the thrust and radiation, or in some triangulation of engines that jeopardizes thrust, what about building the crew quarters as donut and pull it behind one engine, allowing the thrust to go through the whole in the middle.??
my question is, would the radiation be dispersed in a jet like the thrust or would it disperse more freely, thus defeating my idea?
Another good reason for the donut is you can spin it nicely to induce artificial-G for the long trips.
Or am I just talking out of my butt?

All I can say is it would half to bew a really big dounut

John Creighton · 2005-09-27 17:07:38

I thought I'd say more on this. I think the doughnut idea is interesting. The more the doughnut weighs the more the thrust will be cut down. However, it doesn't even need to be a doughnut. It can simply be a ring of a carbon nana tube cables. Sections of the ship will be attached along the cable. These sections could be crew cabins or cargo holds. Gondolas could move people along the cable from one section of the ship to another. The cable will be attached to the engine by inward cables like spokes but they will be in tension instead of compression. If 1 G of artificial gravity is generated by spinning and the ship is capable of 1 G acceleration then these anit-spokes will be at a 45 degree angle to the direction of travel.

The engine does not necessarily have to be in front of the doughnut but the supporting structure of the doughnut must meet where these 45 degree cables intersect. It is this point where the thrust from the engine will be transferred to the crew cabins via the carbon nano-tube cables. Other cables can be at an angle less then 45 degrees to help support the engine and make it so the ship can turn faster without the doughnut swinging behind the engine. With two points of contact between the doughnut and the engine the doughnut will help provide a counter moment to stabilize the engine in one spot. This may actually help enough to extend the engine a far enough distance so it is actually behind the doughnut.

With such a design we gain the fuel efficiency of anti matter but we are limited in acceleration meaning it would take many generations to reach the next star with such a configuration.

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#51 2005-09-03 17:59:47

Re: Antimatter - More viable than fusion?

#52 2005-09-08 14:23:54

Re: Antimatter - More viable than fusion?

#53 2005-09-11 20:04:56

Re: Antimatter - More viable than fusion?

#54 2005-09-16 09:53:02

Re: Antimatter - More viable than fusion?

#55 2005-09-16 11:16:19

Re: Antimatter - More viable than fusion?

#56 2005-09-16 11:57:55

Re: Antimatter - More viable than fusion?

#57 2005-09-27 03:30:32

Re: Antimatter - More viable than fusion?

#58 2005-09-27 16:40:43

Re: Antimatter - More viable than fusion?

#59 2005-09-27 16:47:17

Re: Antimatter - More viable than fusion?

#60 2005-09-27 17:07:38

Re: Antimatter - More viable than fusion?

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