"Given the millions of billions of Earth-like planets, life elsewhere in the Universe without a doubt, does exist. In the vastness of the Universe we are not alone."
Albert Einstein, the great theoretical physicist of the 20th century
Could our whitish blue-green world called Earth be the only life-bearing planet in the Universe?
This has been the enduring question asked by countless humans since the beginning of time. Now, in the 21st century, the indirect evidence scientists have gathered so far is telling us it is highly unlikely we are alone. The number of sun-like stars in the Universe are innumerable (just in the Milky Way there are at least 10 billion of them), the essential chemical elements to make life are available everywhere in the Universe, the ability of these great campfires formed by the stars to cook up all the required chemical elements are there, the oodles of time for elements to naturally come together into various new molecules and long chains of molecules that could ultimately create a crude form of DNA and with it the beginning of life as we know it (and this does not include the possibility that advanced alien life travelling the stars could "seed" new Earth-like worlds with life), the relative ease by which complex molecules needed for the creation of life is spontaneously produced given enough time, the growing number of planets detected beyond our solar system of which a number are Earth-sized, and the discovery that a number of these planets are located within the Goldilock range that allows water to exist in its three physical phases, and finally knowing it is technically feasible to build a spaceship to travel to the stars using nuclear technology (and we have not even touched upon electromagnetic concepts for propulsion using the Abraham-Lorentz formula for charged objects emitting radiation that promises to solve interstellar travel forever), are all indicating a remarkably high probability for the existence of ETs. The only reason why some people might argue against the odds is because they have not seen the direct evidence as yet. The old argument of, "I will only believe when I see it" point-of-view. The ubiquitous view we always see among the more hardened and rational scientists among us. As such, they are likely to belittle the arguments in favour of ETs. As Richard Dawkins, a British evolutionary biologist, tried to rationalise the situation:
"The argument in favour of alien life existing at all is weaker than the argument that if it exists at all, it will be Darwinian life [that is life evolving in accordance with Charles Darwin's theory of evolution]. But it is also possible that we really are alone in the universe, in which case Earth...is the most remarkable planet in the universe." (1)
The reality is that the arguments for the existence of alien life are no less probable than the arguments in favour of Darwinian life taking place on Earth. Both must rely on indirect evidence, and the indirect evidence for both so far is surprisingly strong.
Therefore, it should come as no surprise that the great thinkers throughout human history have argued for the existence of extraterrestrial life for good reasons. Much of their argument has been on the basis of shear numbers of stars in the universe and translating it to a field of millet and trying to imagine the field growing only one grain. It just seemed inconceivable for anyone to think that we could be the only ones to exist in this universe. Today, scientists, and especially among astronomers, think along similar lines thanks to the shear numbers of stars.
The numbers game is just one aspect. Fortunately we have far more indirect evidence in favour of the existence of extraterrestrial life. Sure, we can choose any corner of space, try to look as far as you can with the most powerful telescopes and you will be greeted with the sight of billions of galaxies. Yet a typical galaxy can have literally billions of stars. Just in our Milky Way alone, we have an estimated 100 billion stars. And our nearest galactic neighbour — the Andromeda galaxy — has more than 400 billion stars. These numbers are mere drops in the ocean of the universe. When faced with this overwhelming numbers game it is not surprising to find more and more scientists supporting the ancient Greek philosophers.
But today, scientists have refined what we know by looking at how molecules can spontaneously form on their own with the right sources of energy. They can calculate the distances of invisible exoplanets from their parent stars to get an idea how many might be suitable for the development of life, assuming the conditions are similar to our planet. And after looking at extreme conditions around hydrothermal vents and other places, scientists have seen how life can exist in primitive forms eve when we think there should be life. Even in space, frozen bacteria can survive the harsh radiation-filled environment in certain protected regions inside porous rocks, or on the surface of a spacecraft.
Given the knowledge we already have and the indirect evidence gathered so far, we can state with reasonable confidence that ETs are most likely to exist and in reasonable numbers. As Dr Benjamin Moore, a former professor of biochemistry at Liverpool, England, said in 1913:
"It was no fortuitous combination of chances, and no cosmic dust, which brought life to the womb of our ancient mother Earth in the far distant Palaeozoic ages, but a well-regulated orderly development, which comes to every mother earth in the Universe in the maturity of her creation when the conditions arrive within suitable limits."
The question today is not so much about whether life in the Universe exists. Rather, we should be asking, where should we be looking to find the definitive evidence?
Are we looking far and wide to find the evidence?
At the moment, not too many scientists are confident the technological challenges of interstellar travel can be solved any time soon (ye of little faith, and goes to show how little effort has been made to study the Abraham-Lorentz formula by conducting the crucial experiment). As a result, a number of dedicated scientists involved in SETI, such as Dr Jill Tarter, are touting for more funding to help listen for and promote the possible existence of alien radio signals using radio telescopes. Not only that, but we already have scientists believing the only way to find ETs is by building bigger and better radio telescopes on Earth…
…on the dark side of the Moon...
…and in space to help with the search.
If this isn't enough, there is no shortage of private companies and individuals willing to make do with cheap off-the-shelf electronic equipment to transmit powerful radio waves into space thinking aliens will listen and make themselves known to humanity, if for any reason they do not hear from the aliens.
Should we communicate with ETs?
On the opposite extreme there are scientists in favour of ETs who believe it is better not to send signals into space because it could be dangerous for our survival. In a recent conference of top space experts from around the world held by the International Astronomical Society met in Valencia, Spain, Michael Michaud, a former U.S. diplomat, started the initiative of concern when he argued at the conference in 2006:
"If you travel at one-tenth the speed of light and you're coming from the nearest star it would take 43 years for you to reach the Earth. That sounds like a long time to a human, but what if the spacecraft coming in this direction is not inhabited but is a machine. It doesn't care about the passage of time. What if the people who send it, or possibly the machines that sent it, have indefinite lifespans, what if they live for thousands of years? A 43 year trip may not matter." (2)
With this in mind, Michaud presents the following argument:
"You have to look at the possibility that there might be civilizations that are not sympathetic to us, that do even regard us as a potential threat in the long term. I don't know what the answer to this is. But what we need is a discussion among intelligent people that reviews all the possibilities and gives some weight to what is most likely to happen And then hopefully we can reach a conclusion that would enable us to either send a very carefully drafted message or perhaps to do nothing at all."
As an astronomer by day and a keen science fiction writer by night, Dr David Brin has formulated what he believes to be the current ET situation. He said:
"The SETI community have this image that all advanced alien races are altruistic. I don't know that that's true. There is no evidence for this. It is possible that there may be advanced alien races that are not altruistic. If so, do they have ways to harm us. I don't know. That's the key point. We don't know."
We don't know? Actually we do. Assuming ETs have found a way to reach us, the answer lies by looking at our planet. Remember, the mathematics of galactic colonisation? It only takes one civilisation in the Milky to decide to travel the stars even if it takes millions of years, and the time is certainly there for aliens to reach our planet. Therefore, if ETs are advanced enough to reach us and are not altruistic, why are we still here? Surely ETs would have done something to negatively impact on our survival. But they haven't. Surely this must be food for thought for the scientists. How can this be possible? Are we to argue this as evidence of no ETs in the Milky Way, and potentially the Universe? Highly unlikely. Research and careful observations of the universe indicates life should exist and, by implications, given the amount of time the universe has been around, advanced alien civilisations must exist as well. Even the closest civilisation to us could be a mere 4.3 light years away (see the SUNRISE research on nearby stars). We shouldn't think for a moment that we are the only lifeforms in this universe. Indeed, given what we now know is technically feasible using nuclear technology to reach the stars, an alien civilization would have noticed our planet a long time ago as the mathematics of galactic colonisation has revealed very clearly.
Even if by some incredible luck ETs have not noticed out planet (what exactly are they doing?), we have our spurious emissions of television, radio and radar signals to contend with. These are signals that would have already arrived at the destination Mr Michaud is suggesting (i.e. 4.3 light years away) and certainly up to a distance of 110 light years detectable using a telescope as powerful as the Arecibo. The first ETs should have arrived to Earth more than 60 years ago to check out what's happening on our planet, and certainly by now if they haven't.
Any non-altruistic civilisation out there would have by now done the dirty deed on us and colonised our planet if it so wished. So what are these ETs waiting for?
As another argument, imagine one non-altruistic civilisation trying to become a dominant species in the Universe, and perhaps even to take over other Earth-like worlds. How many advanced and altruistic ETs would be sitting around knowing there is a civilisation out there ready to cause them harm? It is unlikely they would do nothing. We can imagine how threatened certain ETs will feel by the presence of this aggressive civilisation capable of reaching the stars. We can expect other civilisations not to sit around and do nothing, or twiddle their alien thumbs as they wait. They will want to do something about it. What happens next is the scary part, especially for the aggressive civilisation. Because all it takes is a slightly more advanced civilisation to introduce a genetically-engineered virus to target and literally wipe out the aggressive species. It wouldn't take much effort to destroy another civilisation. Guerilla-style, an advanced altruistic civilisation can quietly and quickly drop the dangerous biological cargo into the water supplies of the aggressive civilisation. Then it disappears into space, and sits back to watch the aggressors die knowing the universe in its part of the neighbourhood will be in peace and balance again. Sweet and simple.
With this in mind, wouldn't this raise the question of why ETs would want to interfere with other civilisations, especially if there is a risk it could cause harm? For a non-altruistic civilisation deliberate trying to interfere, it has to be even more careful. Anyone else who accidentally harms another civilisation might have a better chance of surviving through the power of forgiveness and working together with other civilisations to solve the problem. But not so for an aggressive civilisation with selfish needs or wants in its own thinking. The only safest approach is to be peaceful, curious, and compassionate. There is no other choice if you want to survive among countless other alien civilisations.
Thus, statements from military officials to justify the need for a defence capable of handling an extraterrestrial threat will have to be complete bonkers when we are talking about civilisations travelling to the stars who are more likely to be peaceful and compassionate to all life forms. As an example, General Douglas MacArthur said in 1955:
"[T]he next war will be an interplanetary war. The nations of the earth must someday make a common front against attack by people from other planets. The politics of the future will be cosmic, or interplanetary."
Nothing could be further from the truth. General MacArthur would be better off sticking to what he knows best in his own job and let the experts in SETI explain the reality of ETs in its true light. That kind of 1950s thinking won't cut the mustard in the 21st century, and certainly not when we are ready to venture out to the stars. The only extraterrestrial threat to consider today are ourselves, and the asteroids and comets heading to Earth. Forget the aliens. They are the least of our worries. They have far better things to be doing than worrying about what we think about them.
Let's face it. The real concern should be with ourselves. Our mentality to acquire everything we can, ue up the resources in an unsustainable way, to make as much profit as possible at the expense of other life forms and reducing the standard of living of those working for the profit-motivated individuals, and thinking we can own anything we like, is where the greatest concern for the survival of humanity will lie. Certainly not with the aliens. We are the greater threat, and it will be how we treat one another on this planet that will dictate how long we will live on this planet.
But why think negatively? And why do we need to dominate our planet as if we own it and can do what we like, and then think we can do the same? Can we not keep our interference to the absolute minimum and utilise recycling techniques to create what we need, and not always what we want, and just let other species grow and evolve in their own way? Who are we to play God with life on Earth?
We have to remember that the principle of non-interference with other civilisations could end up being the wisest approach to guaranteeing the survival of every civilisation in the universe no matter how aggressive some civilisations might choose to be. Such a lesson could be important for humans here on Earth.
What does this mean for radio communications as a way to talk to ETs?
With all that has been said, why should scientists continue spending taxpayers' money building bigger and better radio telescopes if there is not a high hope of communicating with them assuming, of course, other civilizations are indeed practising the ancient principle of love known to religious people and the more modern psychologists as non-interference? And if they have built the interstellar spacecraft to take them to the stars, what's the point of sending radio signals in space given the long time delays in receiving a reply? A total waste of time. It might help the scientists improve the odds in Drake's equation by at least doing something to search for alien radio signals. But it would be an incredible waste of time and money searching for ETs if we focus purely on the radio telescope option!
So what's the alternative?
NASA is considering sending a probe to Europa in the hope that we can find alien bacteria growing in the liquid water below the ice. This is certainly a more sensible approach. The only risk, however, is that the probe could contaminate the water with its own Earthly bacteria (it only takes one to survive the travel to this moon onboard the probe and flourish in the liquid water of another planet or moon) and then where will we be? Back to square one in this whole ET debate. Because, can we be absolutely sure we have found alien life? Surely there must be a better alternative.
But what could that be?
It is time to solve the problem of interstellar travel
Maybe it is time we get down to the business of solving interstellar travel in the physical sense, and just go out there to observe advanced life forms that we know cannot have come about through earthly contamination. It means the work of a SETI scientist must focus just as much on finding a solution to this problem of interstellar travel as any other aspect. This becomes even more important if aliens are playing the non-interference game with us. Because if aliens have found a way to break the so-called prodigious energy barrier for interstellar travel and can reach us in the physical sense, but choose to keep quiet with us, what's the point of radio communication? We need to broaden our thinking.
As another reason to solve the interstellar travel problem, what if something happens to our planet because of say a collision between a big enough asteroid or comet and the Earth or our Sun suddenly goes kaput? We would all be in serious trouble unless there is something available to us by way of a technological ark to help take us to the stars.
Building spaceships not only makes sense, it is essential for our survival. It should be seen as an important activity for humans to do on this planet as growing food. We need both to protect our future, and both help us to find the answers to our greatest questions.
Sure, we will always have overly rational scientists in our society who have this unshakeable belief that travelling to the stars in the physical sense is impossible because of the enormous time and energy that must be expended, let alone the problem of getting funding to find out if the belief is a justified one or not. But they are a dying breed of thinkers as ideas of exponential acceleration in electromagnetism starts to get introduced.
As shocking as it may be to hear for some scientists, there is indeed a solution. Sitting within those advanced university textbooks on electromagnetism exist a rather poorly understood and studied area of electromagnetism involving the emission of radiation from the surface of a charged object. It is here where the answer lies to this interstellar problem. Not fast enough, you reckon? Rubbish. The Abraham-Lorentz formula gives a special case solution showing any charged object emitting radiation in one direction will cause the object to recoil in the opposite direction. And the movement is described as exponential. The word "exponential" should raise eyebrows among scientists, because this means dramatic movement over time. The kind of acceleration that you need to reach very close to the speed of light in an extremely short time-frame, far shorter than the traditional fossil fuel or even the nuclear technology option can ever achieve (which are both linear in the acceleration they produce). Even talk of inadequate energy available to make this happen also falls by the wayside when we realise the solution to the formula is suggesting a self-feeding of its own emitted electromagnetic energy, as well as an accumulation of energy from the surrounding environment as the charge accelerates. Combine this with one other factor needed for this acceleration to take place in reality (and essential for reducing any dampening forces to restrict this exponential acceleration), and there is no reason why we cannot achieve interstellar travel. It is all within our grasp. In other words, no need for a separate external force to keep it accelerating in the ideal case. In the real world, we need some energy to initially start things off. But once there is a tiny jolt to the object from the radiation and we aintain that tiny jolt, each successive force added not only increases the speed, but the next force is stronger and stronger as more energy from the surroundings gets added by the accelerating charge. There is nothing a space crew would need to do but maintain the jolting action. Give it time and a critical moment is reached when the acceleration is so massive that it can cause considerable difficulties for the crew to withstand the inertial forces. But that's what we want. Because then we can control the acceleration through careful adjustment of charge and how we emit the radiation. And there are techniques to minimising the inertial forces using simple electromagnetic concepts.
As the mathematics shows quite clearly, nothing would stop the object from accelerating exponentially in a straight line. It will get faster and faster until Einstein's Unified Field Theory kicks in. Here the oscillating electromagnetic field generates a gravitational field. This gravitational fis probably nothing more than radiation from the surroundings pushing all mass and energy, but either way, all it takes if a critical energy density in the emitted radiation reached at a certain speed. When that happens, the emitted radiation bends on itself. It becomes recycled. Reach that critical level of near perfect recycling, and it should be technically possible to turn off the energy to the system and watch the radiation do all the work of self-sustaining acceleration.
That is the clue to solving the problem of interstellar travel. It is not about wasting the energy into space and finding ways to acquire enough fuel to achieve sufficient acceleration. Too much mass is needed through this traditional approach to acceleration. What you need is recycling of the energy and means of tapping onto the energy of space as the energy gets concentrated by the accelerating charge to maintain the energy, and reduce it over time as the charge reaches phenomenal speeds. It is all a question of recycling energy, not wasting it forever into space.
Then the only remaining tricky bit is knowing how to emit radiation in one direction and how to deal with any dampening forces in the environment. And neither of these aspects are hard to deal with at the engineering level if one thins about it carefully.
All this is telling us is that the only reason scientists have not discovered the reality of this solution and applied it in reality is because they cannot believe their own eyes what the mathematics is telling them and cannot see it occur in reality under the right conditions, and instead they have chosen to see it as a defect in electromagnetic theory that probably doesn't have a bearing in the real world. Rubbish. We have two Russian physicists to thank for this, because they are the ones to suggest that the reason why we don't see charged objects spontaneously self-accelerating in nature is because something in the environment is dampening the motion, so they introduce additional mathematical terms to the Abraham-Lorentz formula to make it closer to the reality they are seeing. Yet incredibly scientists don't go the other way and set up the conditions to reduce the dampening forces so you can make the Abraham-Lorentz solution work in reality. Scientists forget that the whole aim of science is to find out if something can be made possible in reality to accelerate exponentially, not find ways to dampen the motion.
It is all a question of what happens when the minimum energy requirements (part of the solution to overcoming dampening forces) are met to enable acceleration of the slightest amount to take place for a charged object emitting the radiation? What exactly happens to the charged object over time? Does it not support the very essence of what the original Abraham-Lorentz formula has always been telling physicists for more than a century? Well, it should. Yet the reality is that no scientist has even attempted to set up an experiment to find out. That is where we are at today.
And when they do finally attempt the experiment, scientists might realise this concept has already been applied in those symmetrical and mostly smooth electromagnetic vehicles of genuine UFOs observed by various witnesses around the world. Yes, those glowing on the outside, electrically-charged like an electric light-bulb vehicles are based on the Abraham-Lorentz formula. They do apply radiation emission from a charged surface for propulsion. ETs have already known this concept for a long time. It is up to us to figure it out and do the same.
So if other civilisations can work it out, why can't we? Because we can't believe what our eyes are seeing? Ha, how dumb are we?
We have to be careful not to assume too much. We can't assume, for instance, that because something requires a lot of energy that it cannot be done. Or if a solution in mathematics looks too unbelievable to be true that it is okay to ignore it. Yeah, right. We need to make sure we have not overlooked something critical in our discussions, the evidence available to us, and in science that could result in a radical change in our belief and force the development of a new technology we had not considered before. For example, can we be absolutely certain that, say, electromagnetic radiation cannot be recycled in some way and used to propel charged objects to nearly the speed of light? The mathematics is telling us it can be possible. Until we find out, we need to be on guard for the possibility that someone will come up with the solution very soon, and tested it, whether we like it or not.
Don't know how to solve interstellar travel? Well, here's a clue. If a witness claims a symmetrical metallic object can arrive and leave at will and carry with it some odd-looking creatures as in the classic UFO case of the French lavender farmer, can we really afford to ignore the possibility? The more rational scientists might refuse to check the reports because in the words of the American physicist Dr John Archibald Wheeler:
"No phenomenon is a phenomenon until it is an observed phenomenon."
Yet the absence of direct evidence of an observed phenomenon in the skies of Earth is not evidence of absence. Otherwise we should apply it to the search for alien radio signals. If can't find any alien radio signals, so why not say they don't exist? Therefore, why bother with radio communication? But if scientists are prepared to search for alien radio signals while at the same time look towards the possibility of alien bacteria on other worlds in our solar system, then they should equally be searching for ETs in UFO reports. We should not discriminate UFOs from the SETI discussion any more than alien radio signals or some fanciful possibility of finding alien bacteria on a nearby moon.
Why not interfere with us? Imagine the trade and exchange of ideas!
Even if there is the slightest chance ETs are already here and are watching us, why can't they just communicate with us to let us know they are there? Again this comes back to avoiding the possibility of creating harm to our species, or even the aliens. For example, there could be a risk of biological transfer of viruses, bacteria and fungi that could affect our immune systems in a serious way, and vice versa.
There could also be a language barrier to contend with. In UFO reports, we see examples to suggest some UFO occupants speak in a way that cannot be understood by us (e.g., the Antonio Villas-Boas UFO case). However, on the same token, we see examples of where some UFO occupants can, and do, learn our language and communicate with some UFO abductees (e.g., the Alfred Burtoo UFO case), usually to warn us of impending natural disasters on our planet. So why not just send a signal to us?
Or maybe they simply don't want to communicate with us. To communicate means there is a benefit they would receive in doing so. But what exactly would be the benefit to them? Even if the benefits might include having trade with our civilisation, the question we need to ask is, "Do they really need to trade with us to get what they want or need?"
This idea of having trade assumes civilisations will have the same level of technical abilities as our own. Not so for truly advanced civilisations.
In the latter, what exactly do we have to offer to advanced ETs? Nothing. Apart from an occasional biological sample of blood and plant materials for their own scientific studies (and they can do that without us trying to stop them), there really isn't a lot we can offer them (let alone what we can do to control the situation). Furthermore, the universe is an incredibly big place with so many resources available in vast quantities (assuming recycling is not used, which is highly unlikely in order to avoid interfering with other civilisations). There probably wouldn't be anything we have to interest ETs. You might say, "What about gold?" Who cares? There is more gold out there in the universe than we can ever dig out of the ground on Earth. ETs don't care about gold. If they really need it, they know where to grab some. And it will be in far greater quantities our there in the universe than here on Earth. Seriously, aliens won't need gold. Anything else we can make that is unique to us and alien can't make for themselves? ETs will know how to produce it once they see or hear it. Unless the ETs are of equal technical abilities and knowledge, other civilisations that are advanced enough would probably have everything they would need to survive and develop whatever knowledge, technology, culture and art they wish to pursue. And don't worry about having trade with an advanced civilisation. Such an advanced civilisation wouldn't be interested in having trade with a primitive civilisation such as our own. If they want anything from us, they can watch us, listen to our radio and television signals, and pick up biological samples at any time. Then that would probably be enough to figure out who we are and what we are like and build anything they want. No need to make direct contact with us primitive people.
Dr Brin might argue:
"If we beam everything that we have to trade as a gift, all of our culture, all of our music, all of our science, all of our books, then what will we have to trade with? The people who do this may be known in the future as the worse traitors to humanity ever."
The reality could be quite the opposite. Other than a few unique plants and some DNA from certain animals, including humans, it is unlikely aliens will find anything else useful on our planet.
If we want to have trade with an alien civilisation, we need to find those ones that have an equivalent technical know-how as our own. But looking around at our cosmic neighbourhood, there is no evidence at the present time of another unusually high radio emission source around an alternative sun-like star indicating the likely presence of an equivalent technological civilization spuriously emitting radiation. Either we have advanced civilisations out there, or we have places where the ETs are too primitive and not yet reached a level of having developed a technology for them to communicate with us. Looking at the age of many sun-like stars, 75 per cent of them are older than our sun. We can be fairly sure the majority of ETs out there are more advanced, and the rest are too primitive. We are kind of in the middle and could go either way depending on what we do with our technology and how we treat one another and all living things.
But if we ever want an advanced alien civilisation to contact us, the first thing we need to do is get our backyard in order. Because, at the end of the day, we are the greater threat. Not the aliens.
Using psychology to answer the ET question
As with have seen with interstellar travel, finding a technology to solve this problem would help to dramatically increase the odds in Drake's equation in favour for the existence of ETs and in vast numbers. And when we do get to the planets of other civilisations, the probability will become of absolute certainty.
But what if you don't want to build the technology to find out the answer? Is there another way to get to the answer of "Are we alone?"
You see, the principle of non-interference represents a subset of a much broader concept known to the better informed religious leaders and psychologists throughout history. This concept is called love. You may be wondering how the concept of love can provide us with the answer. Easy. Just ask yourself this question: "What is your attitude to life?"
Should your attitude to life be lacking in love, then the answer is obvious: we are alone and the factor L in Drake's equation has to be extremely low. Indeed it is the kind of attitude that may explain why aliens have not made contact with us simply because the number of civilizations in the Milky Way has been calculated to be extremely small. Some scientists think this is because either ETs are very few in numbers, or every civilisation that reach our level of technology eventually destroy themselves. However, this is the pessimistic view. The more optimistic view is that there are probably an unimaginable number of ET civilisations out there, but this is probably more to do with a decision not to communicate with us. Very few will want to given our attitude to life on Earth (and they may do it quietly by giving messages to those humans who get briefly abducted and taken onboard the UFOs, or meet some of our children as in the Ariel School UFo case in Zimbabwe). The rest will not bother. Our attitude has pretty much determined the figure for the factor L and, therefore, the answer has to be, "We are alone!"
On the other hand, if your attitude to life is always filled with love and compassion, then the answer should be clear. For it is through love that the true abundance of life in the universe is finally revealed to us thanks to the great number we can use for L in Drake's equation.
The only reason why scientists ever mention Drake's equation in a discussion on ETs is because they believe we were incredibly lucky to have survived to this point in time, and from now on our future is not looking good given our current state of world affairs. The scientists are not sure what our future will be like. And the way things are going on this planet with nations still fighting each other for resources and territory, scientists are not entirely confident we will survive for much longer. The equation is more of a reflection of how uncertain and precarious we are in our existence. We have lived and continued to live on this planet to this point in time, but our continued insecurities and lack of love, our limited open-mindedness and imagination, and an inability to show a positive look to the future is hampering our ability to see a bright future for all humans. Of course, there have been some precarious moments in the evolution of life where humans could have been snuffed out. An asteroid here or there. Maybe a supervolcano, or a lethal bug or two. All this suggests the probabilities were low for us to survive. But guess what? We have made it through. We are here. And the only factor remaining in the equation is the term L, the lifespan of our civilization. L can be any large number you want to make it. It all depends entirely on how optimistic and hopeful you are about the future. Are you the type of person who can treat other lifeforms (not just here on this planet, but elsewhere in the universe) with love and understanding? Can you allow lifeforms to exist without interfering? And can you seek alternative solutions that would avoid needing to interference with other lifeforms and get whatt we want for our survival? If you believe in the principle of love, then you will know the answer. Through love, life has to exist in great abundance. Then Drake's equation becomes virtually redundant in this argument about whether ETs exist.
In a nutshell, if we don't know by now how to love and treat living things well, including our fellow human beings, no matter how different their views and appearance may be, then we are truly alone in the universe. And maybe we deserve to destroy ourselves because of our stupidity. However, show love and the universe will be teeming with life. And we will survive to see the day when we can observe ETs to any degree of sophistication and intelligence. And with this important insight into our psychology, perhaps the time has now come for all humanity to start laying down their arms, learn to love all living things, and be more curious and open-minded about the wider universe we live in.
Remember, through love, anything is possible. Even the possibility of finding and later communicating with ETs in vast numbers thanks to our choice of showing a positive attitude to life on this planet (and eventually how to solve the problem of interstellar travel).
Are you a loving and curious human being? Show it, and the truth will reveal itself in all its splendour.