Extraterrestrials: A Dime A Dozen
    By Tommaso Dorigo | April 25th 2010 02:55 PM | 61 comments | Print | E-mail | Track Comments
    About Tommaso

    I am an experimental particle physicist working with the CMS experiment at CERN. In my spare time I play chess, abuse the piano, and aim my dobson...

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    Last Monday Stephen Hawking gave a lecture at the George Washington University for the 50th anniversary of NASA. There he discussed the chance of a contact between our civilization and an extraterrestrial one. And he warned about the risks we may be facing.

    Hawking (on the right during a gravity-free flight) listed the dangers: viral agents our immune system is unable to recognize; the superior weaponry of space travelers; or their nature of predators. The scenarios he envisioned are not too different from those of recent blockbuster movies, from "War of the Worlds" to "Independence Day". In the first case, the viruses actually end up helping us; in the second a representation is attempted of the kind of civilization we might be facing if we were found by aliens serially colonizing worlds to exploit them and leave.

    The question is after all not a stupid one. Should we be more cautious with our own broadcasting of signals into space ? So far we have not considered aliens a risk, and we have actually taken a different stand: we sent probes around, signals with our radio-telescopes (famous the one sent by Arecibo to M13, see right). Fortunately, one might say, advertising in open space is not easy to perform -for the lack of a visible target.

    Now, despite Hawking's arguments are hard to counter, I do not share his fears. I think that the chances of a physical encounter are exceedingly small. Because of the distances involved!

    I have always thought that extraterrestrial life is common in the universe. Of course, the temptation of thinking at the matter in other than purely rational terms is high: a small part of the brain of each of us keeps screaming anthropocentrically about ourselves being the necessary product of the universe itself, regardless of our religious faith or absence of same. If we listen to that inner voice, we may reach opposite conclusions depending on whether we consider humanity special or typical.

    Drake's Equation

    Instead, I have always found convincing by itself the vastness of the universe and the sheer number of stars it contains. This has been the subject of considerable scientific debate ever since we realized how big is the cosmos surrounding us. In particular, things have become more quantitative after Frank Drake, in 1961, put together a simple equation to compute -or should I say guesstimate- the number of civilizations presently existing in our galaxy, ones with which we have a chance of coming in contact. The idea is that interstellar space travel is possible, while inter-galaxy travel is honestly too hard to envision; and radio broadcasting from other galaxies are similarly out of the question for the time being.

    While Drake's equation is a good basis for systematic investigations of signals from extraterrestrial intelligences, I care little about the admittedly scarce possibility that we ever receive positive news from our SETI searches. I care more about the fact that, if we consider the whole universe instead than restricting to our small galaxy, and if we omit to require that other civilizations exist at present (whatever this means over billion-light-year distance scales), the probability becomes a certainty.

    Let us first have a look at the Drake equation: it states that the number of civilizations in our galaxy which could in principle communicate with us, call it N, can be computed by multiplying several factors:

    - R = the average rate of star formation per year in our galaxy;
    - Fp = the fraction of stars having a planetary system (never mind peanut-shaped ones -sorry Pluto);
    - Ne = the number of life-ready planets per planetary system;
    - Fl = the fraction of planets that actually develop life at some point;
    - Fi = the fraction of life evolution bringing in intelligence
    - Fc = the fraction of civilizations that develop a technology releasing detectable signs of their existence;
    - L = the length of time that such civilizations broadcast detectable signals into space.

    According to wikipedia, the most recent estimates of those numbers are the following:
    - R = 7/year
    - Fp = 0.4
    - Ne = 2
    - Fl = 0.33
    - Fi = 0.01
    - Fc = 0.01
    - L = 10000 years

    With the above numbers, N becomes 2.1. Besides us, it is possible that there are two civilizations currently broadcasting a signal in the galaxy. A not too encouraging thought for SETI, or maybe a scary one for Hawking; in any case, admittedly a small number, subject to such wild uncertainties (from the unknown error in the parameters estimated above) that we cannot really draw any conclusion. It can be zero, or easily several hundreds.

    So are we alone in the universe ? NO!

    Despite the uncertainties, some conclusions can still be drawn. For let us take a step back: we might content ourselves with the notion of the existence of intelligent life anywhere in the universe. In that case we would be able to get rid of the Fc factor, and we would get the small bonus of summing over all the galaxies in the known universe: at least 125 billions, according to recent estimates enabled by the Hubble surveys.

    The net result is that the meager N=2.1 becomes over 20 trillions! This means that there are presently 20 trillion civilizations around. 20 trillions. Okay, we might have dropped or added one factor of a hundred too many here or there, but the number is still enormous, no escape!

    Is that not a sobering thought ? To me, that is both awesome and saddening. As far as awe is concerned, of course there is no need to explain it. But there is sadness too: for imagine the incredible, unfathomable number of things that we will never be able to know, constrained in our tiny planet, during our insignificant lives. Masterpieces, inventions, acts of bravery, adventures. But also wars, atrocities, catastrophes. The history of the universe will never be written - but it would be quite a read, I am sure.


    If we survive, which is looking more and more unlikely these days, then it seems probable that one day we will communicate with other civilisations. Our current science may make this seem impossible, given the distances, but we should not forget how primitive we actually are.

    Amateur Astronomer
    I tend to agree with Tommaso the number of inhabitable planets is very large. Unlike the Drake equation, I don't leave the outcome entirely to chance or probabilities.

    Consider he amount of energy required to send a star ship to a near by star. For about the same amount of power, a planet like Venus could be moved into a different orbit, for example one of the two unoccupied stable nodes in the Earth orbit.

    It sounds very extreme, but if we gain the technology for travel to other stars, we will also have the means to provide habitat there.

    The question then becomes a rather decisive yes or no. Can we ever travel to other stars? To this I answer yes, and with some neglected fundamentals of well established science.

    A successful technology depends on gravity induction and vacuum energy. These are the only sciences we have that can ever take us beyond our solar system. Gravity induction is required, because that is the only strong acceleration we can withstand without being mashed flat. This is rather well understood science. that is not used for ordinary travel because the power consumption is extremely high, even for a small field effect.

    Vacuum energy is the only power supply that comes close to the field strength required for gravity induction. It is potentially dangerous. There are strict physical limitations for using vacuum energy that are governed by the Heisenberg uncertainty principle. Vacuum energy enforces all of the physical laws and generates the gage group. Altering the vacuum changes the laws of science and the constant properties of space and time.

    Vacuum energy is a loan and must be repaid promptly to avoid serious consequences. Schrödinger described a way that the third law of thermodynamics allows prolonged use of the vacuum energy by construction of non random processes to lower the entropy and prevent the normal repayment of the loan. Then the vacuum collects the debt by other means. The predictable result is a displacement in time and space. If a vacuum energy device is operated on Earth, it could alter the orbit of the Earth to repay the energy loan. In a star ship the loan is recovered by displacing the ship in space and time.

    To make a field effect with gravity induction, a very strong magnetic field is required with multipoles generating an interference pattern. LC resonance is the only way to build up a force field of that intensity. Then the field effect can be lost abruptly by anything that upsets the resonance.

    Returning to the questions about star travel and habitable worlds. There is a technology that predicts the change of planetary orbits, and the displacement of star ships in space and time. It doesn’t come from the adventure writers. It comes from the pioneers in science. The technology has been available for a long time, but is not taught in college, because it is dangerous to use.

    Some people are trying to say they can build the machines in a hobby workshop. More likely it will come from a government program in the western deserts.
    Aliens are typically depicted as being rather similar to us but equipped with spaceships and ray guns, plus maybe tentacles and a few extra eyeballs. But in all probability any civilization we meet would be older by millions or even billions of years. No one, in even the wildest speculative fiction, has come up with a sensible idea of what such a race might be like, what technology they might have, or what might motivate them. I think it is safe to say that as far as communication goes, one does not waste time trying to hold a conversation with bacteria. (We are the bacteria.)

    On this I disagre Bill. I would be happy to converse with a bacterium, if there was a way to do it. Metaphorically, the more so. Any civilization evolved enough to contemplate art is, in my opinion, worth an internship.

    As for Hollywood movies, I think a good example are the aliens that fish out the mekka kid at the end. But Asimov has pictured very evolved life forms in his stories. I remember his short story "The last question" for instance.

    "I think that the chances of a physical encounter are exceedingly small. Because of the distances involved!"

    Tommaso, on Fermi's paradox I recommend to you "A Computational Analysis of Galactic Exploration with Space Probes: Implications for the Fermi Paradox," Carlos Cotta, Álvaro Morales, ArXiv, 2 Jul 2009 ( Carlos is a good friend of mine.

    Hi Francis,

    I gave it a look. Interesting stuff. A similar idea was discussed in a very crazy book, by Tipler "The Physics of Immortality". I don't buy it that such a gigantic effort of mapping the galaxy may be considered necessary by higher intellgences though! The effort is titanic, the returns come after millions of years, and the required positivism goes beyond my generous share.

    I think those estimates for the factors in the Drake equation are very optimistic. The more we find out about the solar system and our planet the more we learn just how special it is to have an environment that remained stable enough for long enough (but not too stable) for us to evolve to our current level. It could be that factors such as Ne, Fl and Fi factor into the probabilities of a significant number of unlikely events and circumstances that were required for us to be here in which case they may be very small.

    Well Phil, the story of the Drake equation tells otherwise. A while ago planetary systems were thought to be exceedingly rare -now they have been recognized as 40% common! Wikipedia has a nice record of historical estimates of the factors in the Drake equation in the relative article.

    Ah yes, but most of those planets and giants and close to their stars. Of course this is biased by the limitations of the observation methods, but still we are along way from seeing that there are many Earth-like planets. I think it is a false optimism to suppose that the other factors will get large just because this one has. Can I assume you have looked at "the rare Earth hypothesis?" I know not everyone is convinced by it but I find it quite persuasive.

    The March 2010 issue of Scientific American featured an article about the structure of Titan, the largest Saturn's satellite.

    In the last five years, Cassini orbiter and Huygens probe have studied in detail this satellite: to make it short, it seems that Titan is a full Earth-like planet (ok, it is classified as a satellite, but who cares), with litosphere, atmosphere and a remarkable full methane cycle that seems to have basically the same features of Earth's water cycle. The main difference would be that the average surface temperature on Earth is close to the triple point of water whilst on Titan is close to the triple point of mehane, making Titan very cold (-180°C) with respect to Earth.

    If I can recall well the basic requirements of the "rare earth hypothesis" for the development of complex life, one could see that these requirements can be fulfilled by planets in very different configurations (not-too-far-not-too-near-from -star planet --> Earth, as well as satellite of a far-from-star planet --> Titan)

    In Italy there is a proverb that says "A single sparrow does not bring spring", thus saying that the mere presence of Titan could be not as meaningful with respect to the rare Earth hypothesis, as I implied above, but now that we have discovered that a planet near to us has the same basic cycles as the Earth (with a different global parameter - temperature), it would nevertheless be interesting to investigate the key factors for having such particular planets by comparing them: one could eventually identify those key factors, and may find that "Earth planets" are not as rare as the "rare Earth hypothesis" implies, after all. [well, I could be wrong, huh!]

    Your proverb is based on the words of Aristotle but in English we say that it is a single swallow that is not necessarily a sign of summer.

    Titan is indeed an interesting moon but not much chemistry can work at such cold temeratures so it is hard to imagine that any form of life could develop in a liquid methane environment. I think Jupiter's moon Europa is a better prospect for life. It is believed to have an ocean of salty water beneath its icy crust and tidal heating should warm the ocean to similar temperatures as the oceans on Earth.

    It is sometimes argued that basic life developed very quickly on Earth so it should develop in other similar places including Europa. The problem is that we dont know what cirustances were required for the start of life. If it required an environment that only existed in the early part of Earth's history then the argument breaks down and there is no reason to expect life on Europa or on early Mars. At least this is something that could be settled by exploration.

    For nearly four billion years the Earth had no multicellular life. It must have required an unlikely event or a very unusual environment for this to change. If that is true then it seems unlikely that multicellular life would develop on Mars or Europa. Of course that is just one step of many that were required to reach the stage of evolution now seen on Earth. Each step required special features of the Earth's envoronment. It had to remain stable and this stability required the right atmosphere, a suitable magnetic field, a large moon etc. But if it had been too stable, evolution would have stagnated. We needed the occassional comet strike, ice age, or volcanic eruption to kick evolution to the next level, but without wiping it out completely. Life also makes use of the tides, and of the land/sea interface and the right mix of chemical elements. These are just a small sample of the features of our planet and solar system that have been identified as important to the evolution of advanced life forms. The right combination of factors could be very rare indeed.

    The point is not that the Drake factors must be small. It is just that there is a good line of reasoning that says they could be very small. If they are small it explains the Fermi paradox. To me it seems like this is the scenario that best fits the limited set of facts that we have so far.

    Consider the extreme corrosiveness of oxygen. This would make it as toxic as chlorine to any normal life based on complex molecules.
    Life sprung very early on our planet, indicating it is not a very unlikely event. On a planet with right temperature and a reductive environment, as our world.
    What kicked in eukariotes and multicellular beings was the introduction of Rubisco, and the Calvin cycle, some 2.5Gy ago. This started the poisening of our environment. First mitigated by the FeII-FeIII buffer, it finally got the atmo- and hydrosphere polluted enough with oxygen to force anaerobic life back to deep niches, unless it was lucky enough to acquire oxydative phosphorylation, by itself or by endosymbiosys. Even then there was a considable advantage for cells to clump together, to exclude the awful oxygen. Less functional or dead cells were kept on the outside, while the more sensitive processes were executed by the cells within. Hence differentiation.
    Is the rise of Rubisco and the Calvin cycle plausible? Very little, but it would unavoidably lead to multicellularity.
    Thus, given Fp and Fe, which will be reasonably guessable in the near future (Fe about 0.002, as Gliese 581f is about the 500th exoplanet studied), I think Fl is not much smaller than 1, and Fi very small, say 10E-6.

    Reconsidering the weird structure and biosynthesis of rubisco (it is partly coded for in the nuclear DNA), its hard to explain conserved malfunctioning, and its entanglement in the Calvin cycle, which has no bootstrapping point, I rather "guess" Fi to be 10E-12 or less. But actually impossible, as this whole complicated process evolved but once in 4.5 Gyr and required several concerted evolutionary steps in nuclear and chlorofyll DNA.
    Can anybody help explain the plausability of rubisco?

    Leaving the beautiful ideas and discussion about extraterrestrial life aside for a while, I feel Hawking has been treated unfair by the journalists (yes, the people we all love); based on different quotes of his talk I read elsewhere, what I understood is that he was simply ironic to the human race when he advised against contact with aliens, nothing hollywood-like. I guess the whole text must be online somewhere...

    His talk was indeed ironic -as often happens with him. I also read different quotes around, and I concur with you in general. But he did mention the risks, specifically those of locust-like aliens, or viruses affecting us.

    The only means for us to currently evaluate/speculate on the nature of aliens is to look at nature and how it operates on Earth. I agree with Dr. Hawking. If, and that's a big if, aliens operate in a manner similar to how nature operates on Earth, then we need to be very careful about being curious. All one has to do is look at what has happened to more primitive cultures on Earth when confronted with a more technologically advanced culture.

    Jeah Jim, I agree - all signs are against a fruitful handshake the first time we meet somebody from far away. That's unfortunate but, as I said, quite improbable anyway.

    I wouldn't worry too much about natural alien viruses - viruses are phylogenetically focused. There are a lot of plant viruses out there, but they don't make us sick. Nor do bacterial viruses.  Birds and mammals sometimes carry viruses that infect us, but even in that case a cross-species jump is a relatively rare event. I don't know of any reptile or fish viruses than infect humans.

    It's unlikely we'll be infected by a virus carried by aliens who share no common ancestry with us - unless the aliens engineer the virus to get us.

    Interesting! Strange that most of the sci-fi literature ignores this thing.

    Sci-fi would be much cooler if it didn't ignore it! So much sci-fi biology ignores the implications of evolution.
    Gerhard Adam
    ... but even in that case a cross-species jump is a relatively rare event.
    That's certainly true, but it doesn't speak to the selection forces that would occur if an alien virus or bacteria were to appear on earth.  If it survived our environment, then clearly there is something adaptive enough about it to suggest that it could exchange genetic information or effect existing organisms.  Even something like wiping out natural barriers might give preferential capabilities to other viruses or bacteria that previously were held at bay, so an alien encounter might simply be a catalyst rather than a cause. 

    On the other hand, there is no assurance that our biological infrastructure couldn't be invaded by a completely different biology.  We live in a world that has evolved all manner of "checks and balances", so we've never really had to contend with a truly outside agent and contemplate the ramifications of alien biology.

    The one thing we know for sure, is that if something can survive, then it can adapt.  Under those circumstances, there's really no way to know how dangerous or benign such an encounter might be.
    Mundus vult decipi
    An alien bacterium would be a different beast. A virus would be extremely unlikely to survive at all, because viruses are based on the specific details of the DNA replication/repair machinery of the host cell.

    If an alien bacterium could metabolize the lipids, sugars, and amino acids found on Earth, it would have a chance, but it's unlikely that it would do so, unless it came from a planet that harbored the same biological macromolecules.

    Of course it's always possible to speculate that some microbe based on completely unknown biology could wipe out earth life, but our best biologically informed speculation suggests that this is not possible. Biology requires chemical specificity, and it's hard to see how an alien microbe could posses the requisite chemical specificity to survive here, unless its metabolism was based on the same biological molecules present on earth.
    Gerhard Adam
    While I understand that this is purely speculative, you mentioned the requirement for compatibility between biological molecules for any viability.

    I also realize that this isn't your argument, but I find it interesting that out of the trillions of worlds postulated, that when it comes to biology, we still maintain the uniqueness of Earth-life.  My point (philosophically), is that if we accept the point that life is common and that there is nothing exceptional about life on earth, then we must conclude that life probably evolved using parallel mechanisms and consequently there would be a great deal of the requisite chemical specificity to make them viable biological competitors.

    After all, if life on earth is biological unique enough to protect us, then we could also argue that life itself is unique enough to be sparse regardless of the size of the universe.  I don't see how we can argue for trillions of civilizations and then suggest that each is biologically unique. 
    Mundus vult decipi
    When accepting that life is common and that there is nothing exceptional about life on earth, we could still conclude that life may have evolved using parallel mechanisms but with different working points for some parameters (carbon-based, nitrogen based, tuned around water cycle, tuned around methane cycle and so on): these parameters would assure different degrees of chemical specificity that would make survival impossible (non-interaction with the new environment, or extinction before genetic evolution enables to adapt to the new environment) in most cases.

    After all, try and throw a naked man on Titan. Or Mercurius. He would die for sure.
    Taking into account temperature only, we see that most earth life forms, including bacteria and viruses, cannot survive below a minimum temperature or above a maximum temperature, and as far as I know this gap is not very large.
    Environmental conditions for a given life form are quite strict, as far as I know.

    Sure, there could be a life system enough compatible with ours to allow heavy interactions like alien viruses, but given the number of possible equilibrium points in the phase space I would say such a situation is quite rare.

    Gerhard Adam
    I don't have a problem with your assessment, however it raises the question about why we should be so interested in communicating with a species with which we share virtually nothing in common.  Given the biological points being made, we would be much better served trying to communicate with whales and dolphins than the effort of communicating to a species with which we share nothing.

    As I've said elsewhere, I can certainly appreciate the curiosity about life on other planets, but once that curiosity is satisfied, what would we hope to gain?  Many people implicitly assume that another civilization would be more advanced and represent a source of new knowledge.  However, what if it turns out we're the more advanced ones.  Then what have we gained?  
    Mundus vult decipi
    Why must it always be about a personal gain, Gerhard ?
    Gerhard Adam
    Why are you pursuing research?  Why are we interested in the possibility of extraterrestrial life?  It's all for personal gain, whether that be personal knowledge or personal materialism.  "Gain" doesn't have to be materialistic, but there is something that must motivate you to wish pursuing such a venture. 
    Mundus vult decipi
    Okay, but I was rather thinking in terms of knowledge. Knowledge is worth pursuing per se, regardless of the risks -or we would not know much about nuclear power, for instance. Whether humanity has gained or not from Fermi's pile is a different question, but I hold that withing certain boundaries increasing one's knowledge in the world around us is always a good thing. And I may agree that it is also a question of taste. Would you like to know the date of your death ? I would, but many would say no no no.

    Gerhard Adam
    Hence my point about "what if they had nothing to teach us"?  While you could certainly envision all manner of research regarding the alien lifeforms themselves, it would be presumptuous to assume that we would have that kind of access (as well as to their planet).

    That's why I said, if we don't actually have access to them or their planet, after our initial curiosity is satisfied that life exists ... what is there left?
    Mundus vult decipi
    Hi Gerhard,

    While I understand your point regarding what we may gain if anything, I do not understand why you pose the question as if material/immaterial knowledge should be the only driving force behind humanity's search for alien life. There are profound philosophical, deeply inherent in our being type reasons as to why we want to know if we are alone, are these not enough in and of themselves? Surely you understand that.

    Gerhard Adam
    There are profound philosophical, deeply inherent in our being type reasons as to why we want to know if we are alone, are these not enough in and of themselves?
    Actually that's the problem.  The deep philosophical issues can be readily answered with a simple "yes" or "no".  Beyond that, what is the point? 

    Whether the answer to the questions regarding other life in the universe are ever answered (and I'm not convinced that they're that important), the problem is what do you do once you've actually established contact.  If we should discover an intelligent signal from space, then our question is answered.  Do we really need to expend the energy and incur the risk of actual contact?

    I'm not dismissing the interest that such a discovery would generate, but I am suggesting that it isn't nearly as important (nor as desirable) as it seems. 

    I would find it interesting to see what people actually imagine the benefit of such an encounter would be once the basic "yes" or "no" question has been answered.  If you think about, it invariably involves some interaction between the two groups that is largely utopian with little consideration for the real ramifications of such an encounter.
    Mundus vult decipi
    If an alien bacterium could metabolize the lipids, sugars, and amino acids found on Earth

    On a related note, I've seen some interesting speculation that this is the reason why we (eukaryotes) are parasitiized by bacteria but not archaea....we share more metabolic pathways with bacteria.

    Biology requires chemical specificity, and it's hard to see how an alien microbe could posses the requisite chemical specificity to survive here, unless its metabolism was based on the same biological molecules present on earth.

    The alternative would be to construct its own ecology from the ground up (out-competing us, rather than eating us), right? I'm guessing that would also be very unlikely.
    Gerhard Adam
    I'm guessing that would also be very unlikely.
    While I don't know how likely something like that is, it is certainly not impossible.  Consider the impact that microorganisms had in forming the atmosphere and environment we have today and out-competing us would certainly be a huge factor. 

    If such an organism were introduced and be capable of utilizing raw materials from our environment to grow and reproduce, why shouldn't we be concerned that a byproduct of its existence is potential contamination of our own resources?  The earth and alien organisms don't have to directly interact for them to still compete and create problems.

    Mundus vult decipi
    Amateur Astronomer
    When speaking about Aliens, we are really talking about space travel and time travel.

    Time travel seems a bit far fetched on first sight, but the science describing it was published in 1918 by Reissner–Nordström and republished in 1942 by Peter Bergmann. Albert Einstein wrote the forward of Bergmann's book and recommended it for college studies.

    In the 1976 Dover edition of Bergman's book on page 206, the time (g44) and space (grs) components of the metric tensor are shown to be altered by electromagnetic fields. Gravity is shown to be weakened by electromagnetic energy. It takes a very large electric power supply to curve space backward and cancel out gravity. That’s why it isn’t done routinely. The topic disappeared from public view after 1955 from decisions that were made in the aerospace industry. Later in 1968 Bergmann didn’t mention gravity induction in his popular book about gravity.

    Andrei Sakharov originated the concept of gravity emerging by induction from the vacuum in 1967. Here is a link to his original work on gravity induction from entropic states leading to recent work on holographic universe theory.

    In recent times Boyd Bushman retired from a long career at Lockheed Martin and gave a number of video taped interviews in which he claimed to have done gravity research at Lockheed Martin with magnetic interference patterns that had some success in weakening gravity. The underlying science has been in public view since 1918, and is not refuted by anyone.

    A conclusion can be made that any alien race with technology of star travel, will also have the ability to alter the passage of time. Space travel and time travel come together in the same science, the same technology, and the same machines. It has been on the leading edge of technology for 90 years. So where are the machines from this technology now?

    When alien races are mentioned with technology that is billions of years more advanced than our world, the possibility has to be considered that they are descended from humans on earth.

    When speaking of alien visitors, I always remember the book of Ezekiel. The report says two bright shiny flying machines landed in a primitive farming community near Nippur Iraq on 31 July 593 BC. One of the machines was called the Wheelworks. It had technology more advanced than our own, but not by much. The other flying machine was commanded by someone who said he was God. The Wheelworks went down in flames with an electrical fire in the high voltage engines. The other machine came to the rescue and brought the disabled craft to a safe emergency landing. It landed in the wrong place at the wrong time. Maybe that answers the questions about where the machines are now.

    The field effect requires an LC resonator to be carefully tuned to polarize the vacuum and conserve energy. There is a risk of sudden power loss if the resonance is upset by anything. Something like this can be found in old writings from India together with a remedy that predates the discovery of resonance in electricity by a hundred and fifty years.

    Any aliens that come to our world will have the technology of star travel and time travel. They might have a family relationship to some of us. The problem with predictions from the Drake equation and similar work is that they tend to make assumptions about life and habitats that are not supported by science or history.

    I agree with Tommaso that the Habitats number in the billions. There is a technical science to support that opinion, and a history from ancient times that tends to agree.
    Jerry, you're absolutely correct about the Drake equation. The assumption is that an alien civilization equals an advanced one that would have the technology to travel here. In reality, our advances that we take for granted are not guaranteed outcomes. How many nations from Earth have gone to the moon? If the U.S. hadn't done it, would anyone else have tried in our stead? They haven't yet. 
    The path that an alien race would take does not go in a guaranteed direction of technological advancement. There are many factors that can inhibit such advancement, that the Drake equation doesn't take into consideration. However, if all of the factors are considered, along with the technological problems that would have to be over come, an argument could be made for the possibility of a few races of alien visitors that might be able to get here from somewhere else. Or even somewhen else, as you suggest.

    BTW, you're absolutely correct about that electromagnetism and gravity connection. Thanks for the link and the references. 
    Gerhard Adam
    According to wikipedia, the most recent estimates of those numbers are the following:
    - R = 7/year
    - Fp = 0.4
    - Ne = 2
    - Fl = 0.33
    - Fi = 0.01
    - Fc = 0.01
    - L = 10000 years
    The problem here is that no matter how you dress it up it is simply a made-up number.  One cannot calculate a probability given the wild guesses that go into the equation.  Even if we assume that some of the guesses are reasonable (although how we reach that conclusion is equally speculative), it doesn't represent a probability of anything.

    While I can appreciate the desire to make an informed guess regarding the possibility of extraterrestrial life, the problem this creates is precisely the same as when creationists attempt to use probabilities to demonstrate how life is impossible.  They are all equally based on unqualified guesses and dressed up as mathematics.
    Mundus vult decipi
    Jerry Decker said
    "... star travel ... technology ...
    More likely it will come from a government program in the western deserts ...".

    Are those the western deserts of the USA or the western deserts of China ?

    Tony Smith

    Hey Tony:
    Don't forget the western deserts of Australia!
    Amateur Astronomer
    About alien encounters there is along history of people reporting visits from people in flying machines that predate the industrial revolution. A lot of the claims have to be dismissed especially those that are less than a hundred years old.

    It isn't one of my major interests, but on one occasion I did look at the older reports to answer a question from a friend. For a bout 4000 years people have been describing things that were far beyond the technology of their times. There is quite a variety but one conclusion can be drawn from the whole group. In 4000 years the apparent level of technology has not changed. You can ask your self what type of industrial society makes no advancements in 4000 years. The most reasonable answer appears to be that the machines have time travel ability as well as space travel capabilities.

    There is really no proof that any of the flying machines came from another living world. There is a rather well established science that predicts encounters with people of earth origin traveling backward in time from several different epochs of the future. If they have time travel capability then they also have star travel technology and the power to move stars and planets around to make habitats else where. Gravity moves everything equally well, and a planet as easily as a grain of sand. Biologically they could be very much like us.

    The old reports of flying machines do not look anything like science fiction. They are more like religious experiences.

    Which deserts will produce the machines? The story of Ezekiel points to 4 nations identified by their mascots. The clues are an eagle, a lion, a bull, and a human face. Some references say ox instead of bull, but the definition of a ox was changed about 300 years ago.
    2 Civilisions per galaxy. But that based upon every star of the right size in the galaxy being capable of forming life bearing planets. But the galactic core has too many supernova explosions, while the outskirts of the galaxy has to far
    heavy elements and even carbon. So there is a galactic goldilocks zone as well as a stellar system goldilocks zero, this makes for a lot less planets, that are habitable. But also I expect civilisions to last longer than 10,000 years, perphaps am and optimist, but once something new in life, such as intelligence develops i expect it to move out and beyond it original point and survive for ever.

    I think it is reasonable that there's other life out there and some of it will be intelligent.

    The question really is - will we ever become intelligent and long lasting enough to contact them - and unless we do - what's the other species reason to contact us?

    I would expect that any benevolent civilization would have something like the Prime Directive - non-interferance in a civiliation that would be destroyed by it - something we on earth have never had - and we are still facing the fallout of European colonization around the globe.

    ANd any civiliation that didn't have a prime directive type concept, probably would want us for our water, earthy resources and humans for food or cannon fodder.

    Gerhard Adam
    ...benevolent civilization...
    Now that would be something truly novel.  Since it is arguable whether such a thing is even possible given the divisions that occur between groups within the same species, one would have to seriously wonder the likelihood of "benevolence" to a species that shared nothing in common with us.
    Mundus vult decipi
    well, there are some species that we treat benevolently - the cute ones we want as pets and less so the ones that are lunch.

    certainly, in human to human contact, there's never been a benevolent interaction between cultures of vastly differing techology.

    I'm just a bit naive in that Star Trek way that any culture that could come up with the tech would also gain the wisdom of using the tech for positive purpose

    but, since nature is red in tooth and claw, I am sure that's wishful thinking on my part - and am mostly glad that it's doubtful that aliens would land here during my lifetime.

    although, I'd love to see the faces of religious leaders if it did happen

    Gerhard Adam
    I'm just a bit naive in that Star Trek way that any culture that could come up with the tech would also gain the wisdom of using the tech for positive purpose.
    While I can understand the sentiment, it is also inescapable that even the Star Trek culture rarely considered other life forms as peers (unless they resembled humans and human societies).  I'm sure you're also aware of how often Kirk violated the "prime directive" when things weren't going the way they thought they should.

    Mundus vult decipi
    Amateur Astronomer
    Reply to Tony Smith

    I read through your book rather quickly and found it interesting.

    It looks to me like you are trying to build up a unified model of particle physics and cosmology derived from fundamental principles, with references to modern science combined with philosophical writings from rational mystics from the past.

    Congratulations on being banned by Cornell arXiv. Acceptance by them would be a sure sign of failure in your purpose. Cornell publishes some really interesting topics and I read a lot of them, but you should realize that they don’t tolerate any ideas that lead to break through discoveries or rapid progress in science.

    ArXiv rejection does not signify success either. I found your book to be intellectually challenging for a person who is already familiar with the topics, but also readable and understandable on second reading at a lower speed. It has some important ideas that I was working with about 35 years ago. Also you covered some interesting new ideas like fractal scaling factors that were discussed in one of Johannes’ pages recently.

    What I didn’t find in the book is what the next steps should be in science, which research programs should be supported, and what kind of machines should be constructed to take advantage of the principles you describe. Your book looks like a specialized encyclopedia where a number of related topics and references can be found.

    So I’m not sure if you achieved your objective or not.

    Thanks for your reply to my comment. I’m always looking for new ideas.
    It is nearly impossible to fathom a universe, even a galaxy, where life doesn't exist in some form or another. Intelligent life is another story, but still seemingly probable when the whole of the universe is taken into account. The problem as I see it, is getting two civilizations that have arisen at the same time to contact each other. Homo sapiens sapiens have been around an infinitesimally small amount of time with regards to the history of the universe (and even just the geological record here on earth). It is impossible to overstate that fact. And the amount of time we have been able to actually transmit signals towards the stars is a tiny sliver of that miniscule percentage. For all practical purposes, 100 years in the geological timescale is equal to zero. The odds that we and another civilization have arisen and attempted to communicate in the same short period of time seems similar to the odds of two people holding pistols at perpendicular angles a good distance apart being able to shoot each others' bullet out of the air. The good news is, that if there are enough bullets flying around, SOMEONE will hit, it's just the odds that it'll be your bullet is miniscule.

    And I also think that the ability to bend space time will be necessary before we can ever communicate with another civilization. Even the "Wow!" signal, which was relatively close, still originated from a star cluster 200 light years away, which means even if it was sent by an intelligent source, the signal originated back when good old George Washington was chopping down cherry trees. Unless these civilizations have mastered the ability to warp time and space, any communications we have with someone else will most likely have taken thousands of years to arrive ONE WAY, and even if these intelligent aliens live to be hundreds of thousands of years old, it won't matter, because we cannot, and for this to be worth our while, we need this communication to be a two-way street.

    Hi Adam,

    yes, chances are tiny, but there are a large number of trials set up. The problem of the time delay of signals is yet another matter. The Drake equation accounts for these factors, but it only answers a question I am not too interested in aswering.
    To me the real question is whether we are alone in the universe, and the answer, as I see it, is "definitely not".

    I am with you on the idea that we are not alone—as I said before, it is impossible to fathom the entirety of the universe being devoid of life except for our tiny speck of blue. The verification of this fact when/if it ever comes would be a wonderful triumph, surely turning religion on its head. Speaking of religion, a bit of a digression, but I do not believe that the discovery of life on other worlds would reduce the major religions to rubble as many hope/believe. Nothing is impossible to believe when you hold the “God” wildcard in your back pocket, even T-Rex’s munching on coconuts 6000 years ago is well within the realm of “faith fact”. So to believe that the discovery of life on other worlds would be anything but another simple leap of illogic for many to harmonize with their religion is a bit naïve.

    But anyways, because of the distances involved, I’m not sure that we will ever go further than simply having the knowledge that someone/thing else is out there. Even if we were able to travel the cosmos, unless we could bend space and/or time, we would have to anticipate where civilization is going to crop up next in order to get there. And really, what do two civilizations being in existence at “the same time” even mean, practically, in the terms of the universe and the vast distances separating the galaxies?

    I agree to all counts. In particular the fact that it is illogical to think that some fact will make religious feelings less strong. Religion at its root has illogicity, blind belief, and funny stories of ghosts, spirits, physical impossibilities. Actually I think that finding an alien civilization would INCREASE the push to spiritualism of people.

    And true, it makes little sense to ask for simultaneity in such a vast place.

    Jerry Decker asks me about my opinion as to "... what the next steps should be in science, which research programs should be supported, and what kind of machines should be constructed ...".

    As to particle colliders, the Tevatron has done brilliant experimental work and I hope that the LHC continues that success, particularly in studying the Higgs sector.
    In the future, I hope that technical and radiation safety issues can be resolved so that a muon collider can be constructed.

    As I am interested in the theory of Dark Energy, I would like to see work along the lines of Josephson Junction work of Paul Warburton et al at University College London Quantum Nanoelectronics Group,
    which might either confirm or refute my theoretical ideas (related to conformal gravity a la Irving Ezra Segal).
    Even it turns out that Dark Energy cannot be accessed/studied by those techniques, the advanced technology may turn out to be useful in ways not now anticipated.

    As to unification theory, I like my Clifford algebra E8 model but am realistic enough that I do not expect any institutions to even try to work on it.
    I would hate to see it adopted by any important institution if the institution followed current practice of bandwagon promotion and attack on alternatives,
    maybe it is for the best that I work on it alone and just put it on the web
    (the main drawback being that my web material may be so complicated that it is hard to read and understand, which is my fault for being a poor expositor).

    As to engineering projects, I would like to see widespread development of: safe nuclear reactors used for electricity and sea-water desalting and hydrogen energy systems;
    rapid rail transport; and
    nuclear-powered space exploration
    massive capital investment (and job creation) along those lines,
    corresponding reduction in investment in unstable Ponzi schemes based on derivatives etc that now have nominal asset value on the order of most of a Quadrillion dollars, and very little job creation or any other social benefit for those not directly involved in the Ponzi schemes.

    Tony Smith

    I've now published the first of a three part series about Hawking. The current one deals directly and uniquely with his whole alien invasion announcement. It's filled with video so although it's a decent length, part of that is due to all the embeds that make it up. Only at ...
    I've now published the first of a three part series about Hawking. The current one deals directly and uniquely with his whole alien invasion announcement. It's filled with video so although it's a decent length, part of that is due to all the embeds that make it up. Only at ...
    I remember Hawking once stating that putting that gold disk on one of the Voyager probes, giving our exact location and a plethora of information about humans was a very bad idea. I tend to agree with Hawking. Even though the odds of some extraterrestrial species actually encountering the Voyager probe are astronomical, given the enormity of space, still, we don't know what's out there. And if they're anything like us but with far more advanced technology, then God help us all if they do run across the Voyager probe. Better to err on the side of caution.

    I'm all for passive SETI. But announcing our presence in a universe about which we know very little is not a terribly bright idea.
    "But announcing our presence in a universe about which we know very little is not a terribly bright idea."

    I agree and I disagree...

    I agree becouse, We trully don't know what exist outside this planet. We are still too small compared to the supposed aliens that can travel to our planet, obviously that, if they find us, they will be technologically more advanced that us, and even if they initially have good intentions "power is the ultimate aphrodisiac" (Heinz Alfred Kissinger ), so better we have caution.

    I disagree becouse, we are a curious specie, it's part of us and we can't fight it. We have to know if we are alone or not (probably not). It would be an amazing experience to finally discover life. Imagine what we could learn with them if they are friendly! Infinitus possibilities!

    Sooner or latter we'll find out the truth. As the old saying goes "the truth always comes to the fore". But, we must be prudent. Know more, then find out.

    So, JD, you fail to reach a conclusion. Would you send out in space messages like "we're here, come and get us ?" or not ?

    No, I wouldn't Tommaso. Precisely because of that, I said we need to be careful. That is, find out more, move more, and only later discover more.
    We are not yet sufficiently developed to start screaming at the universe: "HERE WE ARE!"

    Obviously that it would be an enormous experience for us, meeting those criatures. But, we don't know the sufficient to start a communication of these magnitude. So, I have an ambivalent opinion. I want to meet aliens (I think everyone here wants that), but I want to have shure that I won't be incarcerated becouse of our curiousity...

    Can you reach a definitive conclusion, Tommaso?

    Me ? No. But I think chances of being spotted by a predator race are zero. I also think that sending plaques or other advertisement material into outer space is only good to us, to advertise our science on the ground.

    Maybe aliens really are a dime a dozen.  The question then is: Why have they seemingly not tried to communicate with us?

    Let us assume that on any planet with life, there will be cycles of expansions and extinctions of biomes and species.  Climate and geological cycles will cause the deposition of at least some fossil fuels.  Let's use a working definition of 'intelligence': an intelligent species has the mental and physical abilities to make use of the fossil fuels to enhance its ability to survive.

    Of such intelligent species, some fraction will make and use technological discoveries and will use more fossil fuels.  Of those, some species will use ever more fossil fuels in geometric progression.  Of those, some will so alter their environment as to wipe themselves out: the others will simply use up all fossil fuel resources.  Of the latter, some fraction will discover atomic energy.

    Those species which fail to develop atomic energy will, within about 200 years of becoming a profligate technology-based society, be forced to revert to a sustainable energy society.  For any planet, the maximum sustainable energy is the planet's total amount of insolation.  Space travel and emission of signals into space represent a loss of that energy and a reduction in sustainability.

    Of the civilisations which develop atomic energy, some fraction will develop nuclear fusion energy.  Of those, some fraction will realise that the profligate use of fusion energy will cause global warming due to the 2nd law of thermodynamics.  Only this highly intelligent civilisation has a real chance to develop space travel.  These are the only aliens who will have the potential to become exploring space trekkers.  Of these, only some fraction will have an interest in space exploration beyond their own solar system.

    The trekmeisters will come to know about other civilisations.  Having seen one or two inferior civilisations they may work on the basis that if you've seen one, you've seen them all.

    At this moment we could be just one of countless billions of profligate civilisations.  The chance of a trekmeister civilisation being so close to us that it will not have 'seen them all' before encountering our tiny planet is vanishingly small.

    From the Encyclopaedia Intelligensia:
    Wotwestandon -  a generic name used by almost all civilisations to denote their home planet in whatever language.  Of these, the vast majority are planets which we designate as 'Notworthlookingat'.
    First, I think that there aren't two equal planets and two equal species. What you said Patrick, is perfectly applied to our specie. We don't know anything about the "others".

    Second, I'm not sure but isn't possible for the govern to hid something?.... Something that they don't want that the people know about, to avoid panic, for instance?! (but this is only my conspiration theory :P) And Area 51 is a very misterious place....

    Third: "only some fraction will have an interest in space exploration beyond their own solar system". Even if what you said is correct, the universe is infinitus, I'm sure that this small fraction is compound by a big amount of aliens interested in space exploration.

    Cheers ;)

    Gerhard Adam
    I'm not sure but isn't possible for the govern to hid something?
    Definitely, the government is always hiding something, however it isn't likely that they can hide something like an intelligent alien species.  This isn't because I trust the government, but rather why would an alien species cooperate to such a degree?  Bear in mind that an alien species visiting Earth will have invested huge amounts of time, energy, resources, and technology to arrive here, and if they are superior to us technologically, there isn't much our civilization can offer them that would be of use (at least to the degree that they would prefer to cooperate rather than just explore on their own).

    So, I'm forced to conclude that while our government certainly has many secrets, and if possible would keep even more, I don't believe that aliens is one of them.

    More importantly, just witnessing the current oil spill, the aftermath of Hurricane Katrina, and the multiple wars the U.S. is engaged in, doesn't suggest that we have access to much useful technology that hasn't originated here on Earth.
    Mundus vult decipi
    No, I'm not saying that we are using technology that hasn't originated on Earth. Imagine that aliens are just studying us, hidden to don't be discovered... becouse, even being less technologicaly advanced doesn't mean that we aren't inteligent and dangerous. So, it's easy for the government to hid such a thing! Just a word and it's confidential.