Moontanman

You seem to be under the assumption (as Davies is) that all biologists are looking for DNA. That is not so. In fact this is just a relatively recent technique. An organism, regarding whether it does possess DNA or not should do something measurable. However, each and every organism we were able to identify does possess DNA. If they are a significant number of alternative lifeforms around, we should be able to see even one single example of it by now.

You say significant, what number would be significant? .0001% ? if one out 10,000,000 microbes is non DNA life then that means there are non DNA life forms on our planet. Even one species of non DNA life form is significant. another question is why would you think that Non DNA life forms would be obvious by their metabolism by products? Can you look at the biosphere of the Earth and extrapolate backward that everything we see is the result of DNA life? You seem to be assuming that a non DNA life form would be producing something so strange it would stick out. I think that non DNA life forms , to survive, would have to be part of the natural cycle of life we see already and so would not stand out as different just from their by products. I suggest any life forms on the Earth would have to be a part of the same cycles we already see simply because they would have to adapt to life with DNA life forms or die out. Unless they inhabit some odd place where DNA life cannot exist and we never look there. Would we see silicone microbes being brought up by lava in volcano's? I agree that they don't have to exist but I think it cannot be ruled out completely. Nessie has been ruled out completely, sea serpents are almost certainly sighting of known organisms. The Kraken was thought to be imaginary as Nessie until we realized giant squid existed and accounted for the sightings. Looking is a good idea, it's the assuming that is bad, assuming there is non DNA life is bad, assuming it cannot be is just as bad.

If we assume they are present and even plentiful, but we are just no able to see them, well what is the difference to the invisible unicorn, or Nessy?

You do make a good point but I think non DNA microbes are less likely to have an obvious effect than invisible unicorns, invisible unicorns have to eat, they would leave physical traces on the Earth and if they existed they could be detected, looking for Nessie has shown it not to be real. I see no reason to just assume there cannot be any non DNA life on the earth.

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My question is:

"If life formed so early in the history of the Earth, thereby implying that it was a more likely event than we think, how come we see only evidence of 1 type of life on the Earth? Why does the tree of life only trace life's history only to one primordial life form? Why aren't there more trees of life?"

I think you are looking at this wrong, it's thought by many that life did indeed start in many different places and some of these did indeed die out but it is also thought that many of them merged in one way or anther to form the ancestors of life. If you must use the tree analogy think of them as the roots of the tree merging to become the trunk. RNA viruses are thought by some to be evidence of this, they are shadow, a remnant of at least one of those linages. It has been postulated their might still be RNA life forms on the earth other than RNA viruses and just not being seen as what they are or more likely being very rare or existing in places where we don't look or don't think to look. it's a complex idea and as charonY has pointed out there are lots of competing ideas and little evidence of anything but DNA life.

I don't think standard fusion is the panacea everyone seems to think it is. Fusion releases energy in the form of neutrons. These neutrons make surrounding materials radioactive. Stopping these neutrons is difficult and makes the material that stops them radioactive. there is a possibility of aneutronic fusion which could be used to turn electromagnetic radiation directly into electricity with no neutrons and the accompanying radioactivity but we will have to master regular fusion first. The fuel for aneutronic fusion is very rare on the earth as well, further compounding the problem.

I think we will merge with machines and become cyborgs, able to use a computer to augment your mind directly. Possibly directing many things remotely as easily as we now use our fingers and hands.This will lead to mass consciousness and human who can out preform what we now thin k of as genius many times over. Possibly this will lead to a single human wielding the resources of a modern country or (and I hope this is closer to the truth) result in a human needing far less in resources because you can to so much remotely and even live in a virtual world.

Hmmm, shrooms? Seriously, dreams seldom have any real meaning that is discernible. Certain parts of the brain can give you what seems some real symbolism and it feels like it has real meaning but the effect is just your brain responding g to it's own stimuli. I used to have waking visions of flaming red symbols floating in the air and I knew they had deep meaning. It turned out i had peculiar type of migraine and the correct blood pressure medicine made them go away completely even though i stopped taking the medication. Even though the feeling of meaning was super strong I knew it was an illusion. Dreams do not have to mean anything, sometimes they are just weird neural firings.

OOOO Ruby, I want to party with you!

If you had a sealed tank of super heavy water that decayed completly you would have a tank of oxygen and helium3. Nuclear decay would break the chemical bonds.

CharonY, I see your point but I think you are assuming we are looking a lot harder than we really are. You assume all metabolic products are products of existing metabolisms, seen or unseen, or that strange metabolisms would produce some odd chemicals we don't see. There is no reason that radically different organisms have to be obvious to our tests. As far as i know all we test for is DNA, there is no way to look at a microbe, naked eye or microscope, and know if it is DNA life. I see no way to tell if there is life other than DNA life on the earth below the level of complex life, no reason to think it might not be part of the ecosystem to the extent it's metabolic by products are considered natural or part of the whole we do see. .

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The point is not that we did not find a specific species as in your example, but we have no evidence of a single organism like that.

No the point is we don't have any way to know if there is one or an entire complex of organisms like that. No way to know, absence of evidence is not evidence of absence.

Actually we don't know if other life forms share our planet with us. it's pretty obvious that complex life can all be traced to a common ancestor but something very few people know is that when we search for life forms on the earth as in bacteria we only search for life like us. The tests we use cannot detect life that is not like us.

http://discovermagazine.com/2007/jul/aliens-among-us

So water in terms for us is life. Without it we'd die. But it could be poisonous to something else?

Yes, for instance to any life forms on Titan water would be the same as molten lava is to life on earth. Earth life developed in water because the temps favored water being present over other possible solvents. See the following link for alternate life forms

http://www.daviddarling.info/encyclopedia/A/alternative_forms_of_life.html

I noticed the post predicted that in one week the whole world would know but the post was first dated almost a month ago.

Mokele, there is evidence that rocks from near by planets like mars have indeed been found on the Earth.

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

It is also thought possible that microbes could be transfered that way, even multicellular organisms could be transfered that way Water bears are a good example or possibly brine shrimp eggs.

They repel?

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No, matter and antimatter would not repel each other according to current theories.

Opps, I misunderstood the question

Well if they legalize it in California then it should be legal here in NC in, oh say, 1000 years....

I liked Moontan's link.

Especially "The phrase "mirror matter" was also introduced by physicist and author Dr. Robert L. Forward "

 

Funny that his name is Forward. I guess with those ideas his name should be Backward, since antimatter is linked with reverse time.

Dr. Forward is a real person, I've have several discussions with him about detecting mirror matter, mirror matter should not be time reversed (I'm not sure it's established that antimatter is time reversed) but mirror matter has it's own antimatter counterpart neither of which strongly interacts with matter or antimatter.

What are you talking about lucky? You asked a question, i did my best to give you a lead in a direction that might give you some answers, why the hostility?

WTF are you talking about lucky?

Lucky, see mirror matter to see a concept of matter our senses cannot detect.

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

Moontanman, I'm thinking I missunderstood part of your answer in post #5. I was thinking that as the star blew apart the innerlayers collapsed and pressure would build up and push back. My thoughts still are not clear but I am reading up on it when I can.

Thank you.

Gravity prevents any push back, either you get a white dwarf, a neutron star, or a black hole. Once a certain density is reached there is no push back.

Hre is an interesting take on human induced global climate change.

http://www.newscientist.com/article/dn16026-humans-may-have-prevented-super-ice-age.html

Our impact on Earth's climate might be even more profound than we realise. Before we started pumping massive amounts of carbon dioxide into the atmosphere, the planet was on the brink of entering a semi-permanent ice age, two researchers have proposed.

I think it's interesting that my cell phone messes up my computer monitor when it rings, every time with out fail, even if the phone is 18" away from the monitor. Occasionally my computer monitor reacts the same way even if the phone doesn't ring as though a random signal is moving past. Sorry if this is off topic.

A zipper and fold flat furniture is more of case of using current technology in different ways than advanced technology. I don't think an advanced zipper is going to allow up to reverse engineer something we cannot comprehend any more than it could have helped the romans build a integrated circuit.

But I do agree that after a couple hundred years we might get some things as we recognized our new technologies as the beginnings of some of theirs. So I think it's reasonable to say that a space craft that crashed 50 or 60 years ago would not have allowed us to develop very much from it's technology.

I think it's safe to say that any interstellar space craft that crashed on the Earth would have very little technology we could reverse engineer and come up with some wild break through that everyone would look at and say "WOW! THAT MUST BE ALIEN TECHNOLOGY"

Any thing really different or advanced would be almost impossible for us. Even if you took a laptop back just 100 years how much of it could be reverse engineered? Just figuring out how to charge the thing would be a huge challenge.

Alien technology, short of new fangled zippers (whoa! Velcro?) 100's or 1,000's of years ahead of us would be as opaque to our technology as a laptop in 1492.

What prevents the inner layers that are collapsing from bouncing back from the center?

 

I don't understand, what would bounce and off of what?

 

It would seem that the black hole already existed.

Am I brought back to degenerate pressure?

 

No, the black hole is formed by the infalling matter, beyond a certian density it never stops falling inward, time slows as it becomes a black hole but the infall or collapse never stops.

What causes a nuclear bomb to explode? I am under the impression that the explosion is the result of pressure. Is this impression correct?

 

No it is not, a critical mass can form with out the extreme pressures of a bomb. The pressure makes the bomb more efficient resulting in a more complete fission of the uranium or plutonium.

 

I ask because I am just starting to try and understand how a black hole forms. To this point my understanding is a star collapses the pressure causes an explosion.

 

What happens depends on the mass of the star, a sun like star just collapses into a white dwarf.

 

The star then collapses again, except this collapse is unable cause enough pressure to create another explosion.

 

No, not quite, the initial collapse both explodes the outer layers and and compresses the inner layers at the same time into a neutron star or black hole depending on the mass.

 

I have tried to think my way around the next questions. Why doesn't the first explosion blow away enough mass that the formation of a black hole can not occur? Why isn't there a continuous chain of explosions?

 

Sometimes the initial explosion does blow away enough mass to prevent a black hole. Sometimes you get a white dwarf or a neutron star or a quark star, a black hole can only form if the original star is above a certain mass when they process starts, IE it depends on how much mass you start out with. There is no continuous chain of explosions because there is no energy source for them, fusion is over by this time, all reactions past iron consume energy they do not produce it. Gravity overcomes any rebound type energy.