That being said, I don't believe we've been visited.

 

Well, odds are if these aliens had the means to visit us, their planets must be very industrial and developed, yes?

 

They come to Earth to get a taste of pastoral, natural side of things!

 

 

 

Some of it will be more advanced than us, some of it less so, most of it could be equally as advanced as we are, but never invented Tippex™ so they have never been able to correct the errors in their theories of semiconductor physics and therefore never entered the silicon age, not discovered radio-waves, split the atom or built the Toyota Prius, yet alone a space craft of any description. I say "most" for one simple reason - the only example we have suggests it takes life 4.5 billion years to "evolve" to our current level - and it took the Universe 9 billion years to create stars that were stable enough to support the creation of life, therefore all the Sun-like stars in the Universe that could start the life-cycle started at the same time ours did, so the majority of life in the Universe is at our level of evolution (give or take a few million years ).

 

The distance to the nearest stellar neighbour is 4 light-years away (24 trillion miles or 40 trillion km). The fastest vehicle we have is the Space Shuttle, which can travel at 18,000 mph (28,000kph). It would take the space shuttle 157,222 years to get there - this is long before we start worrying about how many Texaco service stations there are along the way to re-fuel it or how we would maintain and service a mechanical system to survive such a journey when bits fall off even the most reliable of systems at alarming regularity.

 

Even if the extraterrestrial life forms have invented a different propulsion system, Newtons laws still apply even if their civilisation doesn't possess apples and thus never had a Newton - energy is required to move a mass and to move it over a vast distance, a vast amount of energy is required.

 

Faster than light travel is simply impossible. Not improbable, impossible. This is not bad maths or selfish physics on our part, it's not the result of our scientists inventing "rules" that stop this from happening or them not thinking "outside the box" or simply "getting it wrong" - it is an absolute limit of the Universe and even extraterrestrial are governed by those same rules and laws, even if their maths is base-3, their physics is written in iambic-pentameter and their Einstein was a hotel clerk. Not believing in this limit is simply not enough to make it go away. (Neither would reading Science Fiction - the keyword there is the second one )

 

Also, there is no magic system of trapdoors and wormholes that would enable matter to travel through them and arrive intact. Entering a singularity would convert all mass into energy, this energy could travel through a wormhole (if such things exist) and be expelled out of another singularity lightyears distant, where it may be converted back to mass - but without the coding-imprint of what that mass looked like when it first entered: you re-enter the Universe as radiation, then sub-atomic particles and then hydrogen - 4.5 billion years later you may have coalesced into a recognisable life-form, but you wouldn't be you anymore and 4.5 billion years hardly qualifies as "faster-than-light".

 

So in answer to the original question: No I don't believe in UFOs - where UFOs are vehicles for extraterrestrial lifeforms. A non-belief that is supported by the observation that the only reasons that these extraterrestrials appear to traverse the trillions of miles of empty space at enormous cost in energy and time is to abduct simpletons, goose cattle and make pretty patterns in wheat-fields.

 

well I want to so i will. but Darqdean pretty much summed it up.

 

some thoughts on the matter of extraterrestrial life, I do believe in life beyond earth, but I find it highly doubtfull there is life that's even remotly as intelligent as we are, of all the life forms on earth only humans can do what we can do, we have both the brains and the body (maybe dolphins are smarter, but they lack the body), so even if there's life on other planets the chances are slimm they are remotly as intelligent as we are, and even if they are, the chance is very slight we can ever run into them, as the chances are a million to one, but still they come.

 

and the speed of light is not the limit, we just haven't find a way to go faster yet, but maybe in time we will.

 

That's why I don't think there's a limit to speed

Subsequently from these tests the US super plane "Blackbird" was developed, we have all seen it but had it been seen before it was unveiled would have been another unexplained UFO sighting!

 

 

I DO believe in UFO! They made some good hard rock albums back in the 1970s (take this as one of the worst jokes in PA).

 

Honestly, like many others in this thread I believe people see UFOs, but I'd never say anything about their origin. From this point of view, I think most scientists show a really UNscientific approach (giving for granted their alien origin, they keep swearing UFOs don't exist...).

 

 

 

 

I couldn't even attempt it.

 

I've often wondered if some are in fact NOT alien, in the sense that they inhabit the Earth already. Like the movie The Abyss.

 

It's a stretch I know, but wasn't Atlantis supposed to be quite advanced around the time of it's disappearance?

 

 

The speed of light in a vacuum is a constant (as I inderstand it - but I admit my understanding is not that great, any corrections are greatly appreciated) which means that electromagnetic radiation (for example radio-waves and light) travels at this speed in a vacuum, as does anything that has zero rest mass. Add something into that vacuum and light travels slower - what you cannot do is add (or subtract) anything to make it go faster.

 

An object with mass requires energy to make it move - the heavier the mass, or the faster you want it to move, the more energy is needed. To make this mass go as fast as an object with zero mass (eg light) you would need enough energy as to make the mass appear insignifcant by comparison. So to make the mass tend to zero, the energy would tend to infinity.

 

BaldJean wrote: to our current knowledge traveling faster than light is impossible; it is contrary to the theory of relativity. however, as Einstein himself pointed out, his theory of relativity did not invalidate Newtonian physics at all; for speeds which are small compared to the speed of light it still works well. so it may be possible (though I have no idea how) that the theory of relativity, however sound it is, may have some as yet undiscovered loophole which would allow massive things to move faster than light. physicists invented the concept of so-called "tachyons" once which could ONLY move faster than light. they had an imaginary mass (whatever that would mean) and moved backwards through time (again whatever that means). I have no idea how one would discover such a tachyon, if it existed, but maybe future physicists will be able to and even find out how to make use of them. we can NOT be sure at all that traveling faster than light is impossible; all we can say it is impossible to our current knowledge. any technology that is significantly higher advanced than the technology an observer is used to appears as magic to that observer

The real problem with tachyons is that they cannot transfer 'information', (by which I mean energy, momentum or mass), which makes them nextdoor to useless for any practical application such as FTL travel.

 

The first reason is because you cannot slow them down - as they lose energy they get faster, so it takes an infinite amount of energy to get them to go slower than the speed of light for us to detect them. We do not "see" light, we can only detect it when its energy interacts with something else and its energy is converted and the same would be true of tachyons.

 

Secondly, because they travel backwards in time if you could detect them, then you would not know the event that emitted them. This make whatever information they were transmitting completely meaningless to us until the event actually happened...

 

(That last one is a bit of a brain-fryer because you would asume that if tachyons travel backwards in time then you could use them to "see" into the future, but it doesn't quite work like that: a tachyon detector would detect tachyons emitted from any point in the future, (ie an infinite number) so unless you track each tachyon forward to their points of origin you wouldn't know which ones contained the information you were looking for and by the time you had done that it would be irrelevant because you'd already be there.)

 

 

Of course there is no reason why we cannot be the most advanced civilisation, after all, someone has to be. Which is probably not the most comforting thought in the Universe given how uncivilised we can be at times. The other sobering thought is that the genetic material we are currently seeding the solar system with is not our own, but bacteriological and/or viral - we haven't spread our DNA, but we have given the Universe a nasty cold.

 

The Milky Way Galaxy is 100,000 lightyears in diameter and about 1,000 lightyears thick at the core, so it would take millions of years to cross it at sub-light speed, and billions of years to completely explore it. Since the self-replicating robot idea is effectively Brownian motion, these timescales can be increased by several magnitudes, (ie 10s or 100s of millions to cross it and 10s or 100s of billions to explore it)

 

Given that the Milky Way is probably only 6 billion years old, any advanced civilisation that possess interstellar travel has not been around long enough to explore anything other than their immediate neighbourhood, which makes them finding our Solar System out here in the cul-de-sac of the inner rim of the Orion Arm highly unlikely.

 

Yet, this is only science fiction. I think scientists (or should I say military authorities around the world) should do their best first to find out what UFOs really are (top-secret vehicles? Plasma discharges? Steven Spielberg's new filming set?).

 

In light of the fact that we now can clone and are active in genetic engineering, would it be such a implausible idea that we are the result of an advanced culture's experiment?

 

 

 

I am not the best qualified to answer this but it can be understood in viewing how chemicals can react with each other, forming new compounds. Over time, these new compounds can grow or attach themselves to other compounds, complexing. From here you move on to proteins, then DNA, then viruses which are debated as being living organisms because they replicate themselves.

 

The Wiki article helps out immensely. My post came up just after it. 

 

 

 

 

You need to understand as well, this stuff took a very, very long time to happen. Pure chance is why we are here in the form we are. Hopping from chemicals to living breathing carbon units didn't happen over a few days.

 

 

 

I was going to say the same thing as Pat (and give the same wiki link) - I too am no biochemist or molecular biologist and only have a scant knowledge of the subject because it is a field of interest for me, but not my actual field of knowledge.

 

As Rich says basically it's small steps over a very, very long period of time. This has produced all the individual building blocks that resulted in the animation of matter, but the actual process and a definitive model has yet to be produced, and certainly not demonstrated in any lab environment.

 

One small point - animate matter does not necessarily imply a brain or even a nervous system - those are inherent in more complex systems than those present at the origin of life - simple animate matter is merely a chemical process. Where evolution comes into play is where these simple animate matter "organisms" survive into subsequent generations.

 

If it was pure chance that it happened here, then there is exactly the same probability that it would happen on a different planet that had the same conditions. What we cannot predict is whether every chaotic event that occurred in our existence is necessary for the process to work, or whether one minor difference halts the whole process - logic suggests that it is a fairly robust system that would defy most variations since life on Earth has survived several mass extinction events in its 4 billion year history.

 

 

/edit: I should haf spelw cheqked that before posting, but too am hingry and need to eat.

 

My point, there is a great amount of unknown and we currently project based on those things we know or theorize. Imagine in one or two hundred years what we may know. Are we in a "the world is flat" mode now?

 

 

 

 

http://br.youtube.com/watch?v=L55jImEhNZ0&feature=related - http://br.youtube.com/watch?v=L55jImEhNZ0&feature=related  

 

Anyway, viewing some old posts here I'd like to add that considering the probability that many Earth-like (or Mars-like) planets could have been formed around 3-5 billion years ago, their geological evolution might have been different than ours, being accelerated in many of them, providing conditions to life earlier that here. A difference of 1 million years (less than 1% in geological calendar) can mean much in terms of the development of higher forms of life.

 

But even if, for instance, the periods of life development were equal to us, a single difference of 20,000 years could be worthwhile. The Homo sapiens appeared circa 200,000 years ago but only around 10,000 years ago they (we) started the "civilizatory process"... can someone imagine in what stage we could be if this process had started 10,000 or 20,000 years earlier?

 

Nice clip - I forgot that one.

 

If we were 10,000 years more advanced than we are now then our physiology, civilisation, culture, theology, sociology, technology and possibly even our biology would be unrecognisable, our scientific/mathematical models would be more refined (and more 'accurate'), but the actual physics of the Universe would be unchanged so our desire to travel the stars would still be restricted by the same fundamental constants and physical limitations.

 

/edit - and Voyager 2 would have covered 13% of the distance between here and Proxima Centauri.

At 1/12th lightspeed that could be possible and violates no laws of physics. I have no argument with that.

All that would mean is that the gravitational constant we are currently using is specific for a locality, (because we calculate it's value based upon observations made here and cannot go anywhere else to make comparative measurements). To make it general it would require a modifier based upon matter distribution, so the "constant" we are using today would become "a constant times a variable" - which is just a refinement to an exisiting concept and hasn't changed any fundamental law of physics. However, since the net effect of this modifier would be negligible the gravitational constant we are using as a constant for our locality would be a good approximation of a constant for the rest of the Universe.

I'm always wary when ideas and analogies are extrapolating beyond their original intent.

 

The Many Worlds Interpretation was intended to illustrate a method by which Schrödinger's cat could be both states as the World would split at the precise moment the radioactive decay triggered the release of the cyanide gas which killed the cat (and not at the instant the box was opened). The key there for me is that the World-split is the result of the quantum event, not of a arbitrary random decision on the part of the observer - the Many-World Universes of SF are of the second idea so not really scientific as I see it. However, it is a good plot device when used intelligently (Arnold and Ace Rimmer being a particular favourite).

 

I feel sorry for Herr Schrödinger, being remembered for a non-serious mind-game rather than for the equation that earnt him the Nobel prize.

Thoughts are not generally not stochastic, they are the result of multiple external stimulii. Even in Schrödinger's example the "thought" that opened the box was triggered by the rules of the experiment - the box was to remain closed for one hour.

 

Even at neuron level each electrical synapse is several magnitudes larger than anything at the quantum (ie subatomic) level therefore immune to random quantum events. (an electrical synapse is 3,000,000 times larger than a proton and the energy required to fire the synapse is 100's of millions of times larger than the energy released by a quantum event).

^ interesting - an hypothesis that could be worth watching if they ever get evidence to demonstrate it is possible or provided an actual mechanism or model of how quantum particles or fields can affect neurons. From what I can gather from a brief skim, they are postulating that the algorithms that constitute thought, and by inference consciousness, are not coded in the hardware, but exist in some vague quantum field... that's a huge leap of faith without some kind of evidence to back it up, but since this area of biophysics is probably a larger unknown than just about any other field of science every postulate and hypothesis is worth exploring.

 

From a scientific viewpoint the arguments against echo what I have said - neurons and synapses are too big to be affected by individual quantum events, but that's not to say it's not a viable hypothesis, just that the actual mechanics for it are a tad lacking.

 

(Not qualified or even mildly interested in commenting on the philosophical view )

 

However new theory's consider 'sound'waves to be responsible.

http://www.scienceblog.com/cms/physicists-challenge-notion-of-electric-nerve-impulses-say-sound-more-likely-12738.html - http://www.scienceblog.com/cms/physicists-challenge-notion-of-electric-nerve-impulses-say-sound-more-likely-12738.html

 

or a combination of both, if these solitons are responsible for transmitting pulses through the neuron netwerk, will that have effect on the quantum-mind theory?

 

Probably not.

 

The article discusses the transmission of information along the length of the neuron as a pressure-wave impluse (like a sound wave), but not how that pressure-wave is created or detected within the Nucleus or via the Synapses. Since experiments and observations have shown the nervious systyem to be electrical (Luigi Galvani ~1780) then it is probable that (if) these 'sound'-waves (exist) then they are electrically generated, therefore the stimumii for neural activity is still electrical...

.

http://en.wikipedia.org/wiki/Image:Complete_neuron_cell_diagram.svg">

 

let's asume the soliton theory is correct.

 

 

However, assuming that solitons theory is correct, then the mechanical generation of the presure-wave has to be triggered by something. For example light falling on the eye, or heat on the finger-tips has to be converted into a form of energy that can produce these presure-waves. My guess is electricity would still be the best method for creating the transition between light and soliton or heat and soliton.

 

One major difference between information propagated through the neural system by sound rather than electricity is speed. Sound through a liquid is considerablly slower (200,000 times slower) than electricity - which actually could be an advantage in a neural system as it adds a delay into the system, for example it can prevent uncontrollable feedback, it can also be used to create controlled feedback (nervious ticks, woodpecker pecking, hummingbird flying) and if you loop a neuron back on itself you have created a memory cell.

 

As I said: Hmmmm...

 

I don't believe in UFOs 'though, if by UFO you mean visitors from another planet.  Leaving aside any so called conspiracy by the US government we can now see so far and in such detail into space and we have not yet found any evidence of another civilisation.  We have not yet found any way by which Star Trek style travel can happen and even if it could we can now see distances into space whereby even with light drives or whatever it would still take generations to travel these distances.  In fact the deeper physicists go into particle physics the less likely it looks that we could ever travel such distances.

 

Strange lights and sightings in deserted areas of the USA are far more likely explained as US military experiments than by alien visitors.  Why would any visitors, after travelling so far, just mess about over some empty area doing aerobatics and putting on a light show?  If they wanted to make contact then surely they would do just that, they'd have nothing to fear from us if they have the technology to get here.  If they wanted to observe us covertly then they simply wouldn't be visible.

 

It's all conspiracy theories I'm afraid.  Some people just want to believe.