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Thanks. That cleared up the stuff about gravity and time dilation anyway. I'd never thought of acceleration due to gravity as being caused by time dilation in the gravity well, but now that I think about it it makes sense. I'm afraid you lost me on some of the later stuff though, the more so as I got farther down. At any rate I had a few questions about that.
I'm not sure what you mean that mass is made of "cohesive energy packets." I thought that mass and energy are the same thing, but can you say mass is made of energy when it's in the mass state. The packets you're talking about are quanta right?
The bit about forces decreasing with the inverse powers of distances makes sense, except you didn't mention gravity. Doesn't gravity decrease with the inverse square? I thought gravity affected more than three dimensions.
I'm afraid I really don't understand stable harmonics and fractal mathematics so I can't say much about that. When you talked about trying to measure the position and velocity of the electron, however, it sounded like the uncertainty principle, but I thought that was due to the fact that the act of observing changes a thing.
I'm not sure if that last question is something i'm supposed to answer or not. The only way I can think of is to convert the energy into mass by colliding the photons with electrons as you describedd. This would create mass, and thus time dilation and gravity, but it would mean making your ship the size of Earth if you wanted 1G. I guess there's no chance for artificial gravity then.
I hope I'm not boring you with all these questions which may seem simple to you. Feel free not to answer if I am.
That is, time dilation is not caused by a gravity well, rather the other way around.
I'd say that both gravity wells and time dilation are effects of mass warping space time; neither causes the other. Acceleration also causes gravity and time dilation, though. That seems to make acceleration the same as mass, which it is not, so maybe I'm missing something here.
I believe the large mass of a planet directly causes distortion in space-time, which causes the space distortion described by General Relativity as well as time dilation. Stable time dilation will not cause gravity or be noticed at all, but a gradient (strong low down and smoothly transitioning to weak above) will cause the effect we call gravity.
This theory doesn't really seem different from Einstein's general relativity.
As for artificial gravity, do we know why mass warps spacetime? If so can this effect be created in any other way?
I agree with your opinion that it's far fetched. This guy puts too much importance on color in what are not necessarily completely true color images. In his processed versions he further enhances the green "vegetation."
One of his images I did find interesting for a somewhat different reason. Here is the link to the original ESA version:
http://esamultimedia.esa.int/images/mar … ...sae.jpg
Zoom in on the crater in the upper left corner. You will see that half of the floor is flat while the other half is not. I do not see this as evidence of current water or vegetation, but it may be evidence of an ancient lake covering half the crater floor. The other possibility is of course a lava flow.
Here is a statue of a Martian lion by Martianangelo, in center, surrounded by three rocks:
It looks to me like an ordinary Martian rock surrounded by a whole lot of other Martian rocks. No lions there.
Unless Martianangelo is a modern artist.
doesn’t fusion happen spontaneously in nature all the time due to the uncertainty principle.
Interesing, I don't think I'd heard that before. Do you know how it is supposed to work?
I think the palladium and deuterium act as kind of a nuclear catalyst by keeping the deuterium in close proximity with each other.
I don't know much about the properties of deuterium or palladium so I can't really comment on that. The general premise of this, though, seems rather different from normal fusion. The article speaks of "hot spots that erupt and then die on the electrode surface." This doesn't seem to be a sustained reaction of any sort (the goal of most research into normal fusion). It seems to imply a process that occurs spontaneously in small amounts in the cell. Each reaction then has no effect on the other. This is quite different from normal fusion in which the heat of the reaction keeps it going.
Honestly I think the jury is still out on cold fusion. It's an intriguing possibility, and there is certainly some interesting evidence in its favor, but there are also a lot of hurdles to overcome. Most important is that it is not adequately explained by any theory. That's no reason to dismiss it though. I'd say we should keep up the research until we get an answer one way or another.
Black Holes Could Contain a Perfect Fluid
How can a singularity be a fluid? Doesn't a fluid have to contain multiple distinct particles. A black hole is, I think, compacted so tightly that it's all one infinitely small particle, a singularity. A single molecule of water for instance isn't specifically a fluid or a solid because it's only one particle. (It could be part of a fluid or a solid.) I don't think you can define a state of matter except in relation to the strength of bonds between it's atoms and the properties resulting from that.
A black hole's temperature should be 2 trillion degrees Celsius
Based on other things I have read I thought that black holes had very low temperatures. Some scientists once believed that black holes had a temperature of 0 K, assuming that with an escape velocity greater than the speed of light they could not emit any kind of radiation. Stephen Hawking proved that they do emit some radiation and thus have a temperature. However, I had always thought that this was still quite low.
At such extreme heat, it is not surprising that it might evaporate like other liquids. That is exactly what happens to black holes in three spatial dimensions, according to a well-accepted theory of particle radiation from black holes by physicist Stephen Hawking.
The evaporation of black holes due to Hawking radiation is not anything like the evaporation of liquids due to heat. The evaporation of liquids occurs when molecules of the liquid gain enough energy to escape from it and break the bonds that hold a liquid in a fixed volume. Hawking radiation involves quantum vacuum fluctuations. These are the creation and subsequent annihilation of particle/anti-particle pairs in otherwise empty space for reasons that I do not pretend to understand. If I understand Hawking radiation correctly, the anti-particle sometimes falls into the black hole before being annihilated and the regular particle avoids destruction and goes happily on its way. (Unless it too falls into the black hole. I'm not sure what happens then.) Anyway this somehow causes the black hole to have to give off some of its mass in radiation. Again I don't really understand why this is.
I know I'm in over my head here. I don't really understand all this stuff, and I'm probably misinterpreting what the article is saying. If anyone here has a better understanding of theoretical physics, perhaps you can point out where I went wrong.
Edit:
I was also initially confused by this article ... but read another article elsewhere that clarifies: the "black holes" they are referring to are not the regular "astronomical" black holes we all know and love, but some feature of string theory ... still very fascinating.
Sorry, I missed that at first. Are these black holes still singularities with escape velocities greater than c?
That's why I'm excited about the possibility that, in cold fusion, we may have stumbled across something fundamental that would, if it can be exploited, revolutionize energy production and availability worldwide.
Right now I don't think there's much good evidence for cold fusion. Certainly the majority of scientists still don't accept it. Which experiments are you refering to in which people "stumbled across cold fusion."
"Hot" fusion may be a viable option for energy production, although at present I don't believe anyone has built a reactor capable of producing a sustainable reaction which yields more energy than is needed to get it started. Theoretically this should be possible, though, and it's a pitty we're not funding more research into it. It could solve our energy problems.
The best living sites may not always be the most scientifically valuable ones, but I suspect the first colony's will be founded around sites of scientific interest rather than mining or industrial potential. The first missions to Mars will of course be scientific. They will probably go to different, widely separated sites. Eventually, however, research bases of several linked habs will build up some of the more interesting places. Something like this is suggested in The Case for Mars. These research bases will gradually grow into full-scale settlements inhabited by ordinary people.
The sites of scientific interest may not have the most PGMs and other valuable minerals, but they will likely be the sites with the most water. That will be an invaluable resource for any settlement.
Even if this cant be used for space elevators its use in other materials for space would prove a great boon. Imagine lighter tougher space suits, lighter space craft and rockets. The possibilities are endless........
Definitely. And space applications are just the beginning. I won't be surprised if in another decade or two carbon nanotubes find a use in almost every industry. They may be to the 21st century what iron was to the 19th or plastics to the 20th.
I'm also surprised the military hasn't started working on nanotube technology. They'd probably beat kevlar for body armor. But then the military has a poor record on body armor.
Of course the space elevator is what I care about the most. I for one believe it can be built and will open space to humanity.
I am beginning to discover that there is a very large range over which people are, and are not, able to "see" recognizable images in random configurations.
That's true. I think it's part of the reason we get debates over faces and other features seen in nature. I'm not quite sure whether you're trying to advance this image as proof of a Martian civilization, or just an interesting possibility. Personally I think that it (as well as the more famous face) is a natural formation. I don't see enough evidence to prove something like Martian civilization. Applying Occam's razor, I still find natural explanations for this and other features the simplest explanations.
After watching Darth Wader in Star Wars blow up a planet,
If there's not enough power for that, that's probably a good thing.
it seems disappointing just how little power is really awailable, even if we used the whole Moon surface.
The good news is we're not restricted to the Lunar surface. Solar arrays can be placed anywhere in orbit around the sun--the closer the better.
At microwave oven frequency, 2.4 GHZ, around 6 km.
That could met a lot of ice on Mars in a small area.
An interesting idea. Probably easier than the other schemes of using giant mirrors and what not for terraforming.
Even if many or all of the millionaires wanting to go into space are just following a fad (which I think is probably true), they may be useful. If they are willing to pay for their own space adventures, it will help to advance technology for space exploration. Even if they don't care about the cause of exploring and colonizing space, these people may help to advance it. They're not heros in my book, but if they're willing to pay large sums of money to go to space I don't mind. Space tourism companies will have to compete to provide the best trip for their high paying customers. This may aid the development of single stage to orbit vehicles. If the fad fades and the millionaires stop looking for trips into space, we certainly won't be any worse off than we were before and we may be better off. I think that they are giving both publicity and funds to the cause of space exploration. We would do well to encourage this. The greed of the rich and powerful may yet help to advance the dreams of true space enthusiasts. Of course I wouldn't count on commercialization alone as a way to create a spacefaring civilization; but it will be an integral part of such a civilization, since it will supply much of the money needed to maintain it.
An analogy to this situation might be found in advertising. I dislike advertising and find it annoying and hate the way it pops up in every conceivable place. But if someone offered to fund a mission to Mars if they could put their company logo all over it, I'd agree in a heartbeat.
The solar energy on the Moon is equivalent to a 100 megaton bomb every 4 seconds.
Do you know what this is in kilowatt hours. When we're not busy zapping asteroids we'll want to use that energy to provide electricity to Earth, space stations, moon bases, etc.
The figures are right, but why to waste the valuable surface of rare ( just a few available at all SolSys-wide) planetary mass objects ( i.e. waste territory) to cover it with solar EM power tapping + power delivery devices?
Vastly more efficient system would be much closer to the Sun situated statite mirror lense system - hanging on the "upward" solar radiation push. If such soleta is put say 1.5 solar radii from the Sun ( i.e. roughly 100 times closer than the Earth/Moon to our star) , it will harness the same amount of energy with 10 000 times smaller tapping area/100 times smaller diameter than the moon. Only ~40 km wide soleta, made from soap-bubble thin "solar-sail" material and weighting only about 30 000 tonnes...
Yes, that makes more sense to me. Solar arrays work just as well in space as on the moon. Besides increased efficiency and no waste of planetary surfaces for space based arrays, they would be easier to build and service in zero-gravity. They are also much more within our current capability than is sending large quantities of material and people to the moon to build solar arrays there.
It looks a little like a face if you use your imagination, but I don't think it's anything artificial. To me it looks even less face-like than the famous "face on Mars." I had to stare at it and the accompanying picture of a real face for a few seconds before I figured out what it was talking about. Without the coloring I couldn't really see the "face" at all. It's just the shape of the hills; just a coincidence. Mars is a big place; if you look, you're bound to see things that look sort of recognizable as human faces or whatever. There are plenty of rock formations on Earth that resemble faces, but no one ever says they were made by intelligent beings. It's just the natural shape of the hills, I think.
How big is the "spider" image? If that was taken with the microscopic imager it would be one small spider.
As for arthropods on Mars, it seems unlikely that Martian organisms would not easily fit into any terrestrial classification. Most likely they would have evolved along very different lines and would not be very recognizable. Even early in its history Martian environments would have been different enough from terrestrial ones that they would probably have favored different evolutionary adaptations. As Mars lost its atmosphere and surface water, any organisms that survived would have evolved along radically different lines from anything on Earth since they would be dealing with conditions totally different from any terrestrial organisms had to contend with. Looking for things similar to terrestrial life is a start, but if we ever do find life on Mars, at least if it's anything more than prokaryotic cells, I doubt it will look like anything we know. Then again, maybe I'm wrong. There's no reason that Martian organisms couldn't have developed characteristics similar to terrestrial ones; I just don't think it's all that likely.
Would there be any advantage to an inflatable cabin for the Mars rover? It would be more hassle to set it up each time you needed it and it would probably increase air loss. On a long journey such as you'd be using the pressurized rover for you'd be in the cabin most of the time both day and night anyway. It wouldn't be worth it to keep setting it up and taking it down.
An inflatable tent might be useful for use on short trips in the unpressurized rover or for emergencies but I don't think it would be good for long term use. I doubt it could be made as airtight and safe as a rigid structure.
Of course once people settle on Mars some will surely take up backpacking as a hobby (I'd probably be one of them if I lived there). They'll need pressurized tents and someone will probably develop them then if they haven't already. It's a pitty you'd have to hike in a pressurized suit and sleep in a pressurized tent and generally live in a separate enclosed environment. It takes away some of what I like about backpacking on Earth. But on Mars I guess that's the only way to go.
Rather than using a railgun to shoot rocks out the back of a ship as propellant, why not use a railgun to shoot the ship off towards Mars or some other destination? Such a railgun would have to be much larger than one on board a ship and would have much higher energy requirements, but since it would remain in orbit around Earth this would not be such a problem. The ship itself would have almost no engine or propellant mass. (Small thrusters would be useful in case any course adjustments had to be made, but mostly the ship would just be coasting after the initial acceleration and wouldn't be carrying any rockets, engines, or fuel tanks left over.)
If a space elevator were built, making a railgun such as this would only make sense. In order for the elevator to keep its center of mass in geosynchronous orbit, it would have to extend cables 36,000 kilometers away from Earth to counter those extending towards Earth. Attaching coils to these to make a railgun wouldn't be that much more work if you were already building the elevator, and I imagine that considerable velocities could be achieved with 36,000 kilometers to work with. A large power plant (solar arrays and/or a nuclear plant probably) would already be necessary to power the space station that would probably be built at the top of the elevator as well as possibly for the elevator itself. Realistically, though, such a project may well not be feasible for quite some time.
Orion would certainly be a big improvement over what we have now for interplanetary travel, but I doubt it will ever actually fly. The legal hurdles and public opposition even to using the bombs only in space would be immense. (Besides there's a treaty banning nuclear weapons in space.) Using fission bombs for launch would never be approved, and rightly so. Even if nothing went wrong the fallout would kill people years later. I think fusion is our best bet for interplanetary travel. It would probably be as much work to get Congress and the public (as well as world opinion) to support Orion as it would be to develop fusion, and fusion would also help solve our energy problems on Earth and thereby generate an immediate profit for its inventor.
I don't know if fusion could ever be safely used for ground launch, though. If we really want to be moving a lot of payload up and down regularly I think we'll need a space elevator.
