Event

2019 Nieman Fellow Benny Becker talks with Avi Loeb, chairman of the Harvard astronomy department

2019 Nieman Fellow Benny Becker talks with Avi Loeb, chairman of the Harvard astronomy department

Avi Loeb, chairman of the Harvard astronomy department and the author of hundreds of scientific papers, has been recognized for his work but nothing compares to the media attention he received for suggesting in 2018 that there may be an alien probe in our solar system. Loeb talked to fellows at the Nieman Foundation in the spring.

Avi Loeb:  You might imagine that since our technology is evolving on three‑year timescale exponentially, so the car that I’m driving right now is so much better than the car that existed three years ago. I can turn it on from my Apple Watch. It’s quite remarkable.

If you think about it, in a thousand years, we won’t be able to recognize the technologies that we are developing. Think about another civilization that had a million years or a billion years. Obviously, to us, whatever we find, any piece of equipment would look just like a cellphone that is brought to the attention of a caveman.

The caveman would look at it and say, “Oh, that looks like a polished piece of rock. I don’t really know what it is.” Indeed, most of my colleagues said that the ’Oumuamua, this object, is a rock. Clearly, we will be shocked once we find some piece of equipment from another civilization. We, ourselves, are sending out equipment out of the solar system.

What I would like to speak about in the next few minutes is about breaking the walls of the solar system. Here is the Sun. The Earth is just at the right distance where liquid water and the chemistry of life could exist. Mars is also at the appropriate distance.

Earth is our own home, but only for a while, and we know why. Part of the problem is once the civilization develops advanced technologies, it also develops the means for its own destruction. We could imagine a nuclear war. We don’t need to imagine. We are already destroying our environment, right?

An interesting question is how long would it take before Earth is not habitable anymore? It’s quite possible that out there, there are lots of dead civilizations.

To me, the most interesting thing to do would be to do space archaeology, which is similar to digging into the ground, except you dig into space and you search for relics, for burnt out surfaces of planets, for artifacts on other planets. That’s an interesting future frontier, finding relics of dead civilizations out there.

We know that eventually, the internal threats, self‑inflicted wounds, will change our planet. Of course, there are external threats from the impact of big rocks, the same type of rock that killed the dinosaurs. They saw this rock coming in. They couldn’t do much about it. Maybe we can do something about it, deflecting it. People are talking about it.

If we want to propel ourselves out of earth, obviously all our eggs are in one basket right now. Everything we care about is right here, except for the ashes of Clyde Tombaugh who discovered Pluto. They were taken by the New Horizons mission.

He is the only person who is actually going out of the solar system. The rest of us are stuck here on earth. If we want to improve our prospects for longevity, we might as well contemplate going elsewhere.

Maybe not humans, because we are not suited for space. Maybe sending out robots with artificial intelligence and 3D printers, so they can print whatever we want elsewhere out of the raw materials.

An interesting point is that you probably are familiar with this thought experiment that Einstein had where he realized that if you cut loose the cable that holds an elevator and you are inside an elevator—you let the elevator fall together with you—you don’t feel the force of gravity for a while until you hit the ground.

For a while, there is no force acting on your legs, because the elevator is falling together with you. It feels in the elevator as if there is no gravity or floating and vice versa if you have a spacecraft without any gravity that is pushing you at the same gravitational acceleration that we feel on the ground, 1g.

You know that pilots sometimes maneuver at 10g. That’s the most that our body can tolerate, but 1g is what we feel right now in this room. In principle, you will have the same sense if you board a spacecraft that is pushing you or accelerating you at 1g.

It’s exactly the same feeling as we have in this room. You don’t need gravity. Gravity and acceleration are equivalent. The interesting coincidence is that if you take 1g, which is comfortable, and you accelerate yourself for one year, you reach the speed of light. It’s an interesting coincidence.

Staying on such a surface for a year, where this self is giving the sense of 1g, because there are rockets pushing this surface, it will bring you to the speed of light. At this acceleration, you can cross the entire universe in 25 years. How is that possible?

This is huge. It’s not 25 light‑years long. It’s much bigger than that. It’s billions of light‑years. How can we traverse the universe in 25 years? It’s because of Einstein’s theory of special relativity. Time will tick much slower in our frame of reference as we approach the speed of light.

In our lifetime, we can cross the universe, if we can only build a rocket that will keep accelerating us for 25 years. The amount of fuel you need for that is perhaps the entire mass of the Milky Way Galaxy. It’s not practical in any way but that is just to give a sense.

[laughter]

Avi:  By now, we have information about many planets that are potentially habitable that travel agencies can advertise as a place to go to. It will just take a while. These places might have a life, as we know it because they have the correct surface temperature, these planets. Liquid water may be there but for that, you need also an atmosphere.

If you take ice and warm it up in a vacuum, it goes to gas. You need an atmospheric pressure that would keep it liquid. For example, Mars doesn’t have an atmosphere. There is no liquid water on the surface even though the temperature is OK. In order to keep the atmosphere, you need roughly the mass of the earth.

The good news is that about a quarter of all the stars have these conditions. It’s not a rare thing. We shouldn’t think about our self as special, that’s my main message. I tell that to my freshmen seminar students. Looking at the sky should make you modest. It’s natural for people to think that they’re special.

When I saw my daughters when they were infants, they thought the world centers on them. When did they mature? They matured when they went out to the street and saw other kids just like them or even better, in some ways.

[laughter]

Avi:  We, as a civilization, will mature once we go to our cosmic street and see other civilizations out there, and realize that we are not unique. Thinking that we are unique is arrogance.

Just like a kid who decides to stay at home because his or her family members are talking nonsense. Who cares about what science fiction writers write? There is a reality out there, and if extraterrestrial civilizations are out there, it doesn’t really matter what people say on Twitter. That’s irrelevant.

If this object was an equipment, it is what it is. People forget about that. They often think that it really matters what people think. What people think doesn’t matter. The church put Galileo in house arrest for saying that the earth moves around the sun. They try to force him to say that the sun moves around the earth. Did that change anything?

The earth still moved around the sun. Who cares what they do to Galileo? That’s the important point about science. That evidence is the key factor. We want to figure out what the world is about, not try to be liked on Twitter. That’s not the issue.

[laughter]

Avi:  The nearest star is Proxima Centauri. It’s about four light‑years away. In fact, the results of the previous election are only halfway to Proxima Centauri. If there is civilization out there, you might say they might think that we’re still intelligent.

[laughter]

Avi:  This star, Proxima Centauri, has roughly a tenth of the mass of the sun, 12 percent of the mass of the sun. It would live for a thousand times longer than the sun, about trillions of years. It has a planet in the habitable zone around it that is 20 times closer to the star than we are from the sun.

It would be interesting to figure out whether this habitable planet has life on it. Now, in order to reach this planet within our lifetime and take a photograph of what’s going on its surface, whether it has oceans or desert, you would want the spacecraft to reach there within 20 years.

That means that it would have to move at least a fifth of the speed of light. When Yuri Milner came to my office, he’s an entrepreneur from Silicon Valley, and said, “Is it possible to push a spacecraft at a fifth of the speed of light?” I said give me six months to look into it. I want to see if that is feasible.

Both of us are 56, 57 years old. If you want this to happen in our lifetime, we really need to move quickly.”

[laughter]

Avi:  There were other habitable planets that were found since then. There is one system, for example, of seven planets that were found. It’s called TRAPPIST‑1.

My daughter, who is 13 years old, said that if we ever move to Proxima b—that’s the habitable planet closest to us—this planet happens to face the star, we think, always with the same side. It’s tidally locked, so there is a permanent day side and a permanent night side.

She said if we ever move there, she wants two houses.

[laughter]

Avi:  One on the permanent night side, where she can sleep, and another one on the permanent sunset’s trip that separates the two sides, where she would have her vacations. Imagine seeing the sunset forever. That’s the kind of place where real estate values will be the highest.

[laughter]

Avi:  Here is a brief biography of myself. I grew up on a farm in Israel, collected eggs in the afternoons, drove a tractor. Then, through some unforeseen circumstances, ended up at Harvard, married my wife, who is sitting over there, [laughs] so I should be careful at what I say.

[laughter]

Avi:  And we have two daughters. Then Yuri Milner came to my office. We started this project, Starshot, to visit the nearest star, and currently, I’m engaged in writing a textbook on extraterrestrial life that should be published by Harvard University Press within a year or so.

The question is how can you launch a spacecraft to a fifth of the speed of light—I’ll be very quick. The idea is to push a sail, the same as the sail of a sailboat that is pushed by wind, except you push it with light, so when a light bounces off a surface, it gives it a push.

Why use light? Because then you are not carrying the fuel with you, so you can reach much higher speeds, and moreover you can reach the speed of light, because you’re being pushed by light.

That was the solution, a very powerful laser that is pushing on a very lightweight payload, roughly the weight of a gram that you find in the heart of a cell phone that includes…

Here is the concept. The concept is to have many small beams that shine laser light on a sail that is released above the atmosphere so that it doesn’t get the friction of the atmosphere, and then with a powerful laser beam push on this light sail over a few minutes, and this light sail will cross a distance during this time of a few minutes, a distance five times longer than the distance to the Moon.

They reach a fifth of the speed of light in the direction of Proxima Centauri b, and it will be equipped with a camera, a navigation device, a communication device, and eventually reach the target, and hopefully will find a habitable planet and send us photographs.

It will take four years for these photographs to get back to us, and this is the imaginary planet that we will take photographs of—it has some green stuff on it that is particularly appealing—and then send us these photographs, and hopefully, we will be able to then learn more about this planet something that we cannot learn at a distance. That’s the concept.

Of course, there are many technological challenges that we’ll not get into. One of the biggest ones has to do with policy, because the same powerful laser beam can be used for other purposes, as you can imagine.

One has to make sure that this is viewed as a scientific project. Let me skip the details. The plan is in the first decade to do research and development, develop the necessary technologies, and then later on construct the launcher.

What I wanted to mention is the fact that I advocate cosmic modesty, as I mentioned. In the past, if you look at these paintings of emperors and kings that were usually males very proud of themselves, they were proud of themselves, because they conquered a piece of land on the surface of the earth.

How big of an accomplishment can that be? There are more planets than grains of sand on all beaches on earth.

For an emperor or a king to be proud, it’s similar to an ant, hugging a grain of sand on the landscape of a huge beach. It’s really not impressive. Just think about it. How many people were proud of themselves over the history of humans for the wrong reasons?

How can we move into space? Of course, we can send robots, as I mentioned, with artificial intelligence and 3D printers. An interesting question is whether we will find such things in our direction.

‘Oumuamua, this object that was discovered by a telescope in Hawaii on Mount Haleakala on Maui. That’s why it got this name, ‘Oumuamua, which in Hawaiian means a scout, a messenger from far away.

This object is very peculiar. We infer that it’s, at least, 10 times longer than it is wide. We don’t have a photograph of it. It’s, at least, three times more integrated than any object we have seen in the solar system. It’s shiny.

Most amazingly, it deviated from an orbit shaped just by the sun’s gravity. We don’t see a cometary tail. We don’t see any gases around it that could give it that push. It’s very peculiar.

There are some other peculiarities about it. There should be more members of this family of objects around in the solar system. We just need to search for them. The next one that comes around, we will examine in great detail.

Of course, the first one—this is the first visitor—astronomers said, “Oh, we know what it is. It’s a comet. It’s an asteroid. It’s something of this type. Who cares?” They just dedicated maybe five days to monitoring this object, which is a crime. They should have put much more attention to it.

Hopefully, next time, they will. That’s one of the purposes I’m speaking about—its peculiarity. I should tell you that scientists that I respect, many of them told me privately that something is really weird about this object, but they were not willing to put this statement in any paper or publicly.

I don’t really worry about that, because the worst that can happen to me is that they relieve me of my administrative duties, and then I would have more time for science. I can roll my life back to the farm, and I’ll be still happy. I can focus on writing books.

I have no problem speaking what I believe is the truth without worrying about the consequences. There are other ways to search for extraterrestrial civilizations. I don’t have time to discuss them in detail. One example is if you take the city of Tokyo and just put it at the edge of solar system, we will be able to detect it with our best telescopes. We can search for artificial light, for example.

We can search for oxygen in the atmospheres of other planets, indicating primitive forms of life. We can also search for industrial pollution, indicating not so intelligent, but technological civilizations. It could be intentional if you want to warm up a planet that is otherwise too cold.

There is this paradox that Fermi brought up about 70 years ago. Where is everybody? If there are civilizations out there, why don’t we see them? One answer that I like is because most of them are dead. By looking at them, we can learn an important lesson to get our act together and behave better than they did, so that we avoid the same fate.

I think the educational aspect to searching for other civilizations and doing space archaeology, my hope is that indeed we will get our act together as a result of that.

Another hope that I have is that once we exit the solar system, we’ll get a message, “Welcome to the Interstellar Club.” We will find there is a lot of traffic out there. Thank you.

[applause]

Benny Becker:  Thank you. I need a moment to digest all of that. We went some places. Starting off, one question that’s on my mind with what you’ve just been talking about. You talked about how you have hoped that finding other life as we know it in other places would help us figure out how to do life better here.

One criticism I’ve heard of people putting their excitement and energy into space colonies in the future is that it could actually distract from trying to get life right here and take the pressure off. Is that something you worry about or is that something you see in the air in the world of people thinking about us moving to space?

Avi:  There are two different lines of research. One has to do with figuring out what is out there and basically trying to understand whether we are alone. That you can do by searching for primitive life in the form of microbes, by looking, for example, for oxygen in the atmospheres of other planets, or you can search for signals or artifacts that indicate that there are other civilizations out there.

This is just for us to know whether we are alone or not, which is extremely important because it will change our perspective. There is a separate track which is more practical is what do we want to move away from Earth and how do we want to go into space? Do we want to move into Mars, for example, and establish a colony like Jeff Bezos and Elon Musk are talking about?

In my view, this is not very practical for a simple reason that our bodies were developed under the conditions of Earth. Once we go to Mars, we will be bombarded because of the lack of an atmosphere, the lack of magnetic field. We’ll be bombarded with cosmic rays, for example. One out of 10 cells in our brain will be damaged by cosmic ray within a year. That’s not talked about a lot.

You need to dig a tunnel deep into the ground on Mars to protect yourself. What you saw on “The Martian” is not really realistic. You can’t really just put a shield around you. You need to go really deep.

Why should we put ourselves in harm’s way? Of course, there would be people saying just like in the Wild West, they are willing to take a one‑way ticket and risk their life, to which I say, “Go ahead. Do whatever you want. It’s your life.” It’s not a long‑term colony that I can envision, at least in the foreseeable future.

What I think we should contemplate is sending equipment that will reproduce what we want elsewhere out of the raw materials there, and perhaps prepare the ground for us to move into those places later. First step in going to Mars would be to modify it in a way that it will be hospitable to us and using robots.

By the way, robots are already used now to replace humans in building, in construction sites here on Earth. It’s not out there. We develop technologies right now that we can apply to space.

In terms of your question, I think space always motivated people to think big. For example, during the Apollo program, there were lots of byproducts that benefited society. We should always dream, arguing that we should think about the practical concerns here on Earth that we should always be worried non‑stop, 24 hours a day about Brexit just because one nation doesn’t get along or does want to do something with another nation. These are issues that you might want to be concerned about.

It doesn’t uplift the spirits of people. It doesn’t really give them a reason to really dream big and do something different. I think space does that. The fact that we didn’t have a second Apollo program affected science and technology in a way. We have to think big because that will help us lift ourselves.

It’s similar to what Oscar Wilde said that many of us are stuck in the sewer, or whatever he said, but some of us are looking at the stars. We have difficult conditions here on Earth, but let’s dream about something better.

I think the future is really in space because one way or another, conditions here will get worse either because we have a nuclear war, we change the climate, there would be an impact of an asteroid or within less than a billion years, the sun will warm up too much that it will boil off the oceans. In the long‑term, we have to move somewhere. There is no doubt about it.

Just saying, “Let’s not think about it,” to me, is the same as the argument that people in a cave made when they said, “Let’s just sculpt all the stones that we have.” That would pretty much be the technology of the future. Let’s just work on sculpting stones. The Stone Age.

The only reason that we are much better off now is we didn’t limit ourselves to stones. Now, why would you limit yourself to stones? Because you start to get a bigger picture about the world and have aspirations about doing something bigger than that.

There must have been a caveman saying, “Let’s do something different.” This first caveman was probably disregarded, suffered significantly for daring to suggest doing something else.

[laughter]

Avi:  I do think that we made progress because we think differently about our life. It’s just a different dimension. It’s just realizing that this two‑dimensional surface that we sit on, it’s so tiny and insignificant in the big scheme of things.

There is so much out there that when we look down and think about the politics of the day and the arguments we have, we could chop it. We are really limiting ourselves. It’s just like putting blinders on ourselves. Let’s think big.

Benny:  You’ve pointed a lot to the ways that these projects shift our perspective and you hope they would shift society’s perspective. I’m curious when talking about politics and relations with people around us living in society. Do you feel that shift in perspective? How would that play out in our day to day lives and not just in moving us towards space?

Avi:  That’s an excellent question. For example, if we find evidence for life elsewhere, the first thing it will illustrate is that we better feel as we are part of one team. We are not individual nations negotiating among each other. We are the human species here on Earth and there is something else out there. Once you realize that, you feel more as part of one family. The human family.

Moreover, I think it will open up a lot of interesting questions about religion, culture, politics, economics because you would start thinking about how to use for the benefit of society what you know about space. You can excavate objects in space, get some minerals that are expensive here.

By the way, does anyone know where these gold in my wedding band, where did it come from? Do you know? Two years ago, we figured out. The astronomers figured out that gold is made in a collision of two neutron stars.

A neutron star is a star of the mass of the sun, roughly the size of Boston, 12 kilometers in radius. It is formed when a massive star collapses. When the core of a star collapses, it makes a giant nucleus the same density as an atomic nucleus. That’s a neutron star.

When two such neutron stars collide, they splash some of the neutron matter that then makes, among other things, gold atoms.

After this discovery that we realized this must be the source based on an event that was detected in gravitational waves a couple of years ago by the LAGO experiment, I started thinking we tend to appreciate the value of gold because it’s rare. The same is true about uranium. It’s also rare. It’s produced in the same events. All these heavy elements are produced there.

What happens to a civilization which happened to be born close to a site where two neutron stars collided? There would be much more gold than uranium there. All the bad things. All the things that people are greedy about in here.

We better not establish contact with such a civilization because for them, nuclear weapons would be quite easy to manufacture.

Benny:  I’m curious. You were mentioning earlier since your paper about ‘Oumuamua?

Avi:  ‘Oumuamua.

Benny:  ‘Oumuamua. Sorry. Thank you. You’ve gotten a lot of media attention. It sounds like that’s not the first round of attention you’ve gotten for some of the things you’ve published on. I’m curious if there’s anything that surprised you in how your interactions with the media have gone on, and in particular, if there’s anything that you feel like frequently gets misunderstood.

Avi:  While it was completely unexpected, I should say, orders of magnitude more that I experienced before. Prior to that, the routine was I write the paper that looks interesting to some people. Some reporters, especially of science magazines, pay attention to it and write either a blog or ask me questions. Eventually, there are some viewers of that. I get some additional reports and so forth.

Now, on this paper, we didn’t plan a press release. We basically had a paragraph saying, “Maybe this is a piece of technological equipment that came from another civilization. We try to explain why we contemplate that.

The paper was accepted for publication within three days in one of the most prestigious journals in astrophysics, which is a record. Usually it takes weeks. And then the editor writes me an email saying, “You might consider having a press release on this one.”

[laughter]

Avi:  I actually tried to suggest it to our press office, to other… They were not sure that it’s worth publicizing. We just didn’t have a chance to react, and then a couple of bloggers wrote about it, and then within a couple of days, I had four television crews in my office one morning, just before I had to go on a trip to Berlin, to a conference, the Falling Walls.

There was a TV crew waiting for me at home when I was about to go to the airport. They came through the door and I said, “Why don’t you have a seat in the kitchen?” They said, “No, uh, we just want your answer to the following question. Do you think there are extraterrestrial civilizations?” and then it appeared in the evening news.

Then, I went to the taxi and got to the airport, got to Berlin. I had in my inbox, when I got there, messages from “Good Morning America,” “CBS This Morning,” and a pile of radio and TV requests. When I was there, it was non‑stop. I didn’t have time even to eat.

There was one time when there were so many reporters—and that’s in Germany—so many reporters interested from television, radio, or newspapers that they put all of them in one room, and it was like what you see often in politics kind of, and I’m not used to it. I didn’t plan for it.

The way I reacted was to use it as a platform to explain the scientific process that in science, most of the time, you’ll have uncertainty, you don’t know for sure something. Some of my colleagues said, “In that case, we shouldn’t come out with any statement. We should figure out the answer, and only then come out of the room and speak to the public.”

To that I say, “This is the reason why the populist movements that you find think of scientists as part of the elite, because scientists do not communicate the process. If we were to show that it’s a human endeavor, just like when a plumber comes to my home and tries to fix a pipe. He or she looks at what’s wrong with the pipe, tries to figure out the problem, and then fixes it.

A scientific process is similar. We are trying to get as much evidence as possible, just like a detective figuring out from all the possibilities around what is the most likely explanation. Most of the time we don’t have enough evidence, so we have multiple possibilities.

We shouldn’t take any possibility off the table until we have evidence to rule it out. If this object looks so anomalous, so peculiar, the possibility that’s it’s an artifact of another civilization should not be taken off the table just because there is fiction literature. Who cares? Let’s consider that possibility, and rule it out with more data on this object or on other objects.

That was the message I tried to convey that the scientific process very often involves proposing explanations to anomalies, and then ruling out one by one all the explanations until the one that survives is believable.

When the public would see that, then scientists would become much more credible, because it would look as if anyone with all this evidence would reach the same conclusion. You should believe the conclusion, because when the scientists agree among themselves, it must mean that there is a lot of evidence for it.

Without showing that part of doing science, I think we’re missing an opportunity, first, to explain to the public the scientific process, which is extremely important because the public funds science.

It’s also important to attract young kids to science, because kids seeing this say, “Oh, really? Yeah, that’s really exciting. We can try to figure out something and at first we don’t know, and then we have some uncertainty, and eventually we figure it out,” and this looks exciting.

This is just like what you do when you’re a kid. If I managed to bring one kid somewhere into science as a result of this media coverage, I’m satisfied. My goal was mainly to communicate the way science is done, but also to argue that my colleagues should be more open‑minded.

We shouldn’t rule out, we shouldn’t leave things off the table just because of prejudice. We know that it led us in the wrong direction in the past, and I can give you an example.

In 1952, there was an astronomer named Otto Struve. He wrote a paper saying let’s imagine what happens if you take Jupiter and bring it closer to the Sun. If it’s close enough so that it orbits the Sun every few days, it will basically tag, move the Sun back and forth in a way that we can measure, so why don’t we search if other stars have a Jupiter close to them?

When this idea was proposed, over the next few decades, to Time Allocation Committees on telescopes by observers, the Time Allocation Committees that were very conservative…

They said, “No, there is no point in looking for that, because we know that in the solar system, Jupiter is far from the Sun, and we sort of understand, we have a theory for that, so there is no point to search for something that we don’t expect. It’s a waste of telescope time.”

That was true for four decades. Forty years nobody looked because of this prejudice, and at some point, some astronomers were able to get telescope time. They did it, and they found the so‑called hot Jupiters, and that opened the entire field of exoplanets, finding other planets, so that was the first discovery that opened the field.

Now you’ll ask, “OK, but eventually science got to it.” The problem is these 40 years. Science is not efficient when you have a prejudice. When you say the Sun moves around the Earth, and you know it to be true because you see the Sun moving, but someone else is trying to argue otherwise, you suppress that person physically, you are basically reducing the efficiency of scientific inquiry.

By having a prejudice, we are losing opportunities to make discoveries. If you are not expecting anything unexpected, then you will never discover something unexpected. That’s my problem.

Benny:  Interesting. One thing I’ve been thinking about as you were talking, those kinds of discoveries about the planets, about the nature of the universe at large, our place in space and time, what do you see as the value of those kinds of discoveries?

Does that still hold even if we continue to have radio silence, if we continue to find that life here is unique and there is no life other places? Do you feel like there still is a lot of value in thinking in these big scales of space and time and spending our time looking way across the universe?

Avi:  Yes, I do think that another result, a negative result, not finding anything has information content. Anyone that went through dating knows that, right?

[laughter]

Avi:  If we find that we are alone, that means a lot because it means that we should really take good care of our future. We the only intelligent species, and we hold some responsibility bigger than our planet. We should not keep all our eggs in one basket, we should protect our future longevity by sending things into space.

Any result that we find is important, but if you ask me what’s my expectation, I don’t think that we are special. I think that once we find evidence, we will find evidence for something shocking that technology would be far more advanced than ours, or that life forms would be very different than ours, because we have life on Earth.

It’s just like looking at a cake. We know the ingredients. It was made of chemicals. The cake is made of flour and sugar, but once you get a recipe book, you realize from the same ingredients you can make many cakes.

The fact that the Earth baked this cake of life as we know it doesn’t mean that you couldn’t have much better cakes made from the same ingredients. I don’t think that we are necessarily the pinnacle of outcomes that one can imagine. In fact, on the contrary, there are many reasons to believe that we are not.

How do we find this recipe book? A simple way to find it is by doing experiments in the laboratory, creating synthetic life. There is actually a team here at Harvard led by Jack Szostak, a Nobel laureate, who is trying to produce synthetic life in the lab.

The importance of that is that by creating life in the laboratory you improve our imagination as to what to expect in space. It’s similar to finding the laws of physics in laboratory experiments, and then using them to explore the universe, and so we can do the same with life. We can create life in the laboratory and then know where to search for it out there.

Benny:  If we were to have an encounter with life out there, is there anything that you’re afraid would happen, or do you mostly just have hopes?

Avi:  I’m [laughs] an optimistic person, but I’m definitely worried. We’ve been broadcasting for more than a hundred years in the radio, and there is a bubble of radio waves surrounding us that went 100 light years or more.

If there is any intelligent technological civilization that is a predator, a hostile colonizing civilization that is worried about us, we will hear from them, [laughs] but they may not care about us if we look rather primitive as we are.

They might say, “Well, it’s just like walking down the streets and, you know, you see ants on the pavement, and you don’t worry about them. If you’d step on one, that’s OK and who cares? You just move on,” and they might think of us as not the smartest kid on the block, as someone that is not worth a lot of attention, which may explain why we haven’t yet figured that they are out there.

The good thing is that we have the technology right now that we didn’t have 50 years ago to search and to recognize if something is out there. We should be open‑minded, and I think we might be surprised, so it’s really exciting, and I think we should listen.

We should not speak at first. [laughs] We have been speaking for a while. That shows lack of intelligence.

[laughter]

Avi:  By the way, there is this syndrome in kids, that the kids that think that they are the most intelligent are usually not. [laughs] You can draw your own conclusion about our civilization, but we should definitely collect as much information as possible so that we do the right thing.

Benny:  Trying to think about humanity with some humility reminded me actually of a friend who recently wrote an article that was talking about humanity, civilization, and capitalism, as a virus.

I’m wondering, you identify yourself as an optimist, and I feel like part of that probably connects to your sense that we should be going other places and spreading ourselves throughout the solar system. Do you have any worry that you would just be a virus‑destroying planet?

Avi:  It’s interesting. I wrote this Scientific American essay on this question, and I basically cited Henry Thoreau who wrote the book “Walden,” and advocated—this is pretty close to where I live in Lexington, Massachusetts—he advocated that we should embed ourselves in nature and not try to change it, not industrialize it.

I tried to expand this theme to space, basically should we just explore space? NASA, for example, has very strict rules about sterilizing space missions making sure that they don’t carry with them any microbes, because otherwise you won’t be able to figure out whether the microbes were out there in the first place, or we brought them there.

There is a bigger question. Elon Musk and Jeff Bezos, they say, “Oh, let’s go to Mars and teleform it. Let’s change it.” I don’t think Henry Thoreau would have been happy with that idea. Perhaps we should just go out there and see what is out there.

Unless we find that some other civilization’s already ruined those places, [laughs] it’s full of trash, and there is not much more damage that we can cause, it’s common practice out there in the backyard. It’s an interesting question as to what we might do to space.

One thing is clear that we don’t have a lot of resources in terms of energy, in terms of mass, and our effect is rather limited compared to how big our galaxy or the universe are. We cannot do much more than be spectators or participate in this big play that is unfolding.

We are not the main actor or actress; that we should pretty much recognize. There is a bigger stage out there. You cannot think of yourself as being the most important actor.

Benny:  I’m just going to ask one more question, and then open it up to the crowd at large. We’ve talked a lot about society, about humanity, about space. I know you’ve done research on black holes and the beginnings of the universe. I’m just curious for you, personally.

Thinking about all of these enormous scales and all of the scales in‑between, how does that affect you day‑to‑day when you just look around and try and live your life, be a person? What changes in the decisions you make and the ways you see the world with having spent time thinking on these big scales?

Avi:  First of all, it makes me not pay too much attention to people, paying more attention to nature the way Thoreau advocated, because people change their opinions, and I don’t have a footprint on social media thanks to my wife. She convinced me, when we got married, not to do it, and I’m very happy at that.

That’s the first thing. I have a lot to think about without hearing the noise that comes with social media that comes from the direction of people. There is a lot to think about, and it’s not on the front page of newspapers. This information that is out there is in the sky, and it’s not coming from people.

It gives you a better perspective about your life also. I don’t feel attached as much to myself being such a small player in that big scheme of things. It’s uplifting in a way, because it’s a religious sense that we’re not talking about God, but we are talking about something bigger than yourself, which is nature.

The amazing thing is, to me, that the laws of physics apply to the entire universe, and we discovered them in the laboratory on earth, so everything seems to obey the same laws. That’s amazing that nature is so organized.

Most of my colleagues take it for granted, but when I go to look at my daughter’s room in the morning, it looks like a mess. Suppose I was just born, and people would ask me, “What do you expect the world to be?” and I would say, “Well, probably a mess.”

Probably different places will obey different laws of physics. That would be my natural expectation. Nevertheless, it’s organized. That’s amazing, and we should be in awe of that fact. It’s a secular sense of awe, but you can give it a religious context.

Spinoza, for example, identified nature with God. There is something bigger than the mundane things we do every day. To survive we have to do these mundane things, but if we all thought about the bigger picture, I think we would be better off, because the frustrations we have on a daily basis are passing.

There are things that if you look at it a decade later, it looks unimportant. However, if you look at the universe a decade later, it’s as important as it was, to start with, and it gives our life a meaning. I should say that I, myself, as a young kid was mostly interested in philosophy and in the big questions.

The only reason I ended up as a physicist is because of circumstances. I had to serve in the military in Israel, and I preferred to do intellectual work, to work on physics‑related projects rather than run in the fields. Eventually, I was offered a position at Princeton, under the condition that I’ll switch to astrophysics.

Then I got to Harvard, because there was this opportunity, and then I got tenure with Harvard. At that point, I realized that this arranged marriage that I had by circumstances is to my true love, actually, that in astrophysics there are fundamental philosophical questions that we can address, but it makes me very different than my colleagues.

The surprising fact is that I’m in a leadership position relative to my colleagues, and that’s unusual because it puts me in a very different light, so to speak.

Benny:  I know I said I was going to open up. I have one more question, I’m sorry.

[laughter]

Benny:  I hope you’ll forgive me. Thank you. I’m sorry, I’m a liar. I hope you’ll forgive me and accept me for who I am.

[laughter]

Benny:  As you were talking about the mess in your daughter’s room, this is something I’ve been thinking a lot about, the question of like is humanity good in the universe? I feel like sometimes I can see the world as there’s gravity that is a force of order and bringing things together, and then there’s all the forces of chaos and pushing things apart.

It seems like as humans we’re built to be on the side of putting… We are a very structured and organized entity, and we tend to do that to the world around us. When you look at the universe, does that change the way you think about that tension, that balance, and how we fit into it and remaining an optimist when thinking about it?

Avi:  You touched on an extremely important question, and let me explain what we currently think about the origin of the situation that you describe. The universe started from very simple initial conditions. The universe as a whole had almost the same conditions everywhere, the same density of matter, to 1 part in 100,000.

There is a popular theory attempting to explain that called “cosmic inflation.” There was an early period where the universe started from a tiny little region that was inflated, and then the conditions were the same everywhere because, initially, they were all associated with the same tiny region that you start from.

That explains why the initial conditions were very special. They were the same everywhere. The universe is looking organized. What happened after that is that there were tiny differences between different parts of the universe just due to fluctuations of the vacuum, quantum mechanics.

As a result of gravity, this force that brings things together, regions that were slightly denser than average collapsed upon themselves and made galaxies like the Milky Way, that later made stars like the Sun. Around which, there was some debris of matter left over that made planets like the Earth.

On the surface of which, there was liquid water, and the chemistry of life started. It organized molecules to the form of life as we know it.

Gravity helped make these objects that are bound gravitationally like the Earth. On the surface of which, chemistry started and made us. Indeed, this introduces variety into the universe because different people look different. The density of air is different from the density of this table, and so forth.

It’s all due to the force of gravity that brought things together in different ways. At the same time, the initial conditions of the universe are responsible for a lot of our history that is so special and organized.

Understanding the origins of life, for example, is a whole field by itself. My textbook is trying to address it. That part of the story is not fully understood. The part that has to do with the beginning of the universe, we have a lot of information about it. It was simpler in a way. We are trying to understand that as well.

You’re touching on very important scientific questions. You can imagine a universe that started differently, that would look very different. You can imagine a universe that wouldn’t have the force of gravity, and then there wouldn’t be life in it the way we see it.

Why is there gravity? Why did the universe start this way? We don’t really know. The way I see, science is an island of knowledge in a sea of ignorance. Unlike the picture that is portrayed by textbooks that try to tell you we know a lot. We don’t know a lot.

We have an island of knowledge in this vast ocean of ignorance, and scientists are trying to increase the landmass of this island. That’s exciting, but we are still pretty ignorant.

Benny:  Questions. [laughs]

Audience Member:  My interest is since you mentioned religion earlier, when we get in contact with somebody else, do you think we’ll become more or less religious? What would that look like?

Avi:  That’s an interesting question. Michael Smerconish from CNN asked a variant on this question when he spoke with me. He said, “What should we hope for? Should we hope for that this civilization is religious or not religious?”

You can think that if they are religious, perhaps they have a better ethical conduct maybe or maybe not. If you look at human history, there were periods of time… It’s a difficult question actually.

Also, the impact on our religions. By seeing that we are not alone, whether we feel less unique. Right now, we feel as the only son or daughter of God kind of. All the attention is on us.

It’s just like this kid who grew up in the family a single kid, and everyone looks… If we find another kid out there, what does it say about us? What does it say about God? That’s an important question.

Now, I’m sure that religious people will have different opinions on that. Many of them will say, “Oh, it’s not in conflict with anything. It’s fine. That’s perfectly fine,” but then it clearly changes some of the rituals.

For example, in Judaism, you are supposed to do some things in relation to the calendar here on earth. What do you do when you go to space that’s not obvious. You have to face Jerusalem, let’s say. Let’s say you’re on another planet.

[laughter]

Avi:  Should you face Jerusalem? [laughs] Then the planet spins. Then you have to change your orientation.

[laughter]

Avi:  It changes your perspective. Once you realize that earth is not everything.

Benny:  Yes, ma’am?

Audience Member:  You talk about other life and that we have to look for another planet to see if there’s other life there. I was just wondering, if the possibilities are infinite, isn’t that a very human‑centric way of looking for another life, because we’re looking for another planet that has water and stuff like that?

Especially you said how ants live with humans, aren’t there infinite other ways of life as well, I don’t know, maybe between different dimensions or… I don’t know.

Avi:  This is an excellent question. What we imagine very often is what we have witnessed or seen. Our imagination is limited by our experience. Therefore, we would search first for life as we know it.

Doing laboratory experiments and producing synthetic life can expand our imagination, for example. For example, it may be possible to have life in a different liquid, not necessarily in water. Maybe in ammonia or something else.

Also, other forms of life. As I said, you can bake different cakes with the same ingredients. It’s not clear whether the DNA structure that we see here is the only way that life can exist.

How do we find it? One way is by expanding our imagination through laboratory experiments. Another way is to visit places and then see if something unusual is crawling on the surface, and it’s something that we haven’t seen before.

I would say that we should just be open‑minded and explore. It’s just like an exploration. It’s going somewhere and figuring out what’s going on there. Once we have a good enough sample of places that we either visited or we looked at, we can get a better sense of how much variety there is for life.

Audience Member:  You’re still looking on planets…

[crosstalk]

Avi:  That’s right. The other thing is biological life. Maybe just a phase, because we are developing currently technologies that may take our place in the future. You can build machines that are much more sturdy than we are that will not suffer from a nuclear war.

It can go into space and …they can be equipment that flies through space, robots that will survive for much longer time than humans.

You can imagine that biology is just a phase, because we are vulnerable to all kinds of harms. Once we go into space, we might not survive. If biology is a phase on earth, it might be a phase also in space. Therefore, we shouldn’t…

Astronomers are looking for life on planets, but I completely agree with you that it may well be that the first evidence will not be on planets. It will be something floating in space that is not a planet, especially if it’s artificially made.

If there is lots of space debris out there, it might be a message in a bottle kind of situation. When I go on vacation, I often like to walk on a beach with my daughters and pick up seashells that were swept ashore. Every now and then, you see a plastic bottle that is of artificial origin.

We should examine every object that enters the solar system and see. Maybe it’s artificial. If it’s not, that may be the first evidence we have for something else out there.

Benny:  Sam?

Audience Member:  There was this collective imagination in the ’60s, ’70s, and ’80s around space. As a kid, my class would go and watch the shuttle take on. That dream that you talked about was because of a kid, but also my child has got a sense of it now.

The latest NASA press releases that they would give off, there’s been a mission up. It’s to fix a toilet or replace this. Every time I hear that, I was like, “Really? This money is going toward fixing a toilet and maintaining a structure that’s falling apart?”

Is that a failure of PR? Is it a failure of leadership? Where did we fall off of that, because that existed?

Avi:  I think it’s a failure of a generation to dream big. I personally refuse to become an adult in the sense of not dreaming more. I think that we should stay kids and dream big. You see that technology brings us very far these days, and it can bring us much farther in the future.

Part of the program why we haven’t dreamt big for a generation could be because of the leadership. It could be because of practical concerns that people said, “Let’s take care of more mundane problems here on earth.”

Part of it is bureaucracy, that you build institutions that are very bureaucratic. They consume a lot of funds but never dream. They develop a lot of fact, administrative fact.

One way to dream is to be mobile. To be able to think about things that are different from the past. Bureaucracies or administrations often don’t do that. Either because they’re worried about the short‑term, they want their budget to be approved for the next year, or because for political reasons they prefer not to get into any friction with anyone.

Obviously, if you want to dream big, there would be a lot of naysayers, people that say, “No. We have a problem to fix. We have to fix the toilet. [laughs] We have to do something.” There would be people that prefer not to go big because it takes money away from other things that they would like to use it for self‑interest.

There will always be resistance but, as a society, we should moderate that resistance and open up the path for innovation. Everyone recognizes that in the business world, innovation…I find the innovation to be much more prominent in the business world than in academia, for example.

In the business world, people are motivated by profit. There are think tanks, the places were… People just are allowed to dream. The leaders of these businesses recognize the fact that if you let a group of brilliant people think big and not be restricted to a particular task, they might come up with the next breakthrough.

We should not just have that for the sake of profit. We should have that for the sake of promoting science more broadly, for the intellectual health of the country. We really need that.

These dreams should be different than just using space for a commercial purpose, or using space for military purposes, or building a space force. It’s not so much national security. It’s more about moving to the next phase in our development, intellectual development.

Benny:  Pete.

Audience Member:  Thanks. I have two questions. First, what’s the most challenging ethical question that has kicked around in your field and how do you navigate that?

Avi:  I would like to make a comment about the humanities. The humanities like philosophy, psychology, sociology, especially philosophy, focused on the past for many decades. Basically, focusing on, for example, Greek philosophers—Aristotle, Plato, and so forth.

There is lot about to think about in terms of advanced technologies in the future that raises ethical, philosophical questions of the humanities. The humanities should be of the future not of the past because…

For example, genetic engineering, there are many ethical issues about what type of changes should we be allowed to make to the human genome, whether society should design the qualities of people within it.

There are issues to do with privacy of data, with how to let computer systems decide about medical treatments to people. If a person gets the wrong treatment, who do you blame?

Do you blame the software developers? You put them in jail because there was a bug in the program. Or if it’s a self‑learning machine, do you attribute the blame to the machine?

There are lots of issues related to the interface between humans and machines. By machines, I mean the advanced technologies that we are developing. I do think that broadly, the managers have a very important role, because they would represent the human aspect of the interface between humans and machines.

There is a very exciting frontier to be occupied by the humanities, which is to advise the people who develop these technologies about how to handle them. We already faced an issue with privacy and social media.

Partly, it’s because people embarked on this frontier without thinking about the ethical consequences. I think the lesson from that is that more people from the humanities need to be engaged in the risks from advanced technologies.

They are like the canary in a coal mine—the people from the humanities. They should alert us to the risks. They have imagination to imagine reality in a different way than it is. The people who develop the technologies do not have these skills.

I do think that ethics is very important in the context of advanced technology, artificial intelligence, machine learning, and genetic engineering. Also, if we find life out there, there would be a lot of issues that touch on the humanities.

Right now, astronomy is about finding dead things like stars, galaxies. In the future, it might involve finding living things. There, ethical issues will come into play. I do think that humanities have a bright future ahead if you ask me, but they have to adapt to the new reality and not think about the past.

I’m sure that people like Aristotle would have been delighted with the latest advances about Big Bang cosmology. For example, Zeno would have been delighted to figure out that he can turn his car from an app on an Apple watch.

Lots of Greek philosophers would have been extremely excited about the current technologies. We should look forward, not backwards.

Audience Member:  Then if you had the opportunity to be put on a rocket ship and just blast it out into space and put your last 10 years of your life, would you do that?

Avi:  Personally, no. I have too many things that I care about here on earth. I would put robots in such a spacecraft. I would not risk my family or myself in doing so. I feel pretty comfortable where I am.

[laughter]

Avi:  I just want to know things. That’s the thing. I want to figure out what is out there. I don’t want to go there necessarily.

[laughter]

Audience Member:  Thank you.

Benny:  Ashley?

Audience Member:  I also have two questions, but the second one is very short. The first one is about the scientific community. If you could tell us more, why do you say you argue that your colleagues should be more open‑minded you said and you argue for cosmic modesty?

I love those expressions, and I was wondering what the cost of it is for the scientific community not being open‑minded the way you described open‑mindedness. My second question is your most favorite science fiction movies.

Avi:  Let me answer the first one first. It boils down to being conservative basically. Most scientists would prefer to be conservative in order to protect their image, to make sure that they minimize the number of mistakes they make during their career.

It obviously has a lot of benefits, because by preserving your image, you can get more honors. You can get awards. You can then basically have a bigger echo chamber that appreciates you.

There is some truth to it, but then there is the risk that the efficiency of the scientific process is reduced as a result, because you are putting blinders. You are preventing yourself from deviating from the mainstream.

If there is some evidence that leads you to suspect that something may be wrong with the mainstream, you will not follow it since you don’t want to get into a confrontation with your colleagues.

You have to dance to the tunes of prize selection committees or selection committees that offer membership to societies, honor societies. If you want to impress those people, you have to do what they like to see.

The great benefit of not worrying about it is that you have freedom. I really am very happy to be in this situation that I am in, because I feel that I don’t belong to any club. That I do what I think is right.

I could have been completely off. Then shortly afterwards, I would be in the street. I’m not, and part of the reason is that some of the things that I advocate are true. Eventually, people recognize that.

I’m taking risks. If I’m wrong too often, then I would not be taken seriously. It’s great that I wasn’t wrong too often so far, but I also think that this efficiency of the scientific process suffers from people adopting the mainstream view.

The people that I’m most disappointed by are young people, because I expect young people not to have a baggage of prejudice and not to be guided just by their ego. What I often see is the effect of social media in making people think alike and the concern about job opportunities.

Young people are worried that if they do something unusual, then they might not get a job. That’s primarily the fault of senior people giving that sense. Just to give you an example, I wrote a Scientific American article—I was a co‑author with two others—that basically said the theory of cosmic inflation was very appealing when it was proposed.

With the latest data, it has some drawbacks. We just wrote a Scientific American article about that. Then a group of more than 30 senior people, some of which are Nobel laureates, wrote a letter to the editor saying, “No, inflation is right.” What is the signal that such a letter sends? That authority matters, that these senior people have to sign on to a petition, on a letter.

I said, “If this argument that they make is right, then it’s enough for a single child to make the argument, and then it will be obvious. Why do you need 30 or more signatories to make the case? That makes no sense.”

The only purpose of having so many signatories, distinguished people, is in order to enforce authority. The danger from that is not for me. I don’t care about it. I didn’t pay too much attention. It’s for the young people.

When they see that they say, “OK. Well, what just happened?” If I were to suggest that something may be wrong with inflation, I will not get a job. That’s clear, because all these people will think that they should get a job, because they believe inflation is right.

This is not the way science should be handled. That’s one shape of the scientific culture that they see that is developing, which is very worrisome.

Not a pattern that they see, which is even more worrisome, is a scientific culture that is divorced from experimentation. That basically says it’s a monologue. We say what nature might be. We don’t care about hearing back from nature what it actually is.

I think of science, of physics as a dialogue with nature where you wait and you check your ideas. Sometimes, you are surprised. Many times, you are wrong. It’s a learning experience.

If you say it’s a monologue, we have a mathematical formulation that allows us to tell that you can unify quantum mechanics and gravity in the form of string theory. It’s mathematically extremely appealing.

I don’t really care that we have no direct evidence for it. Frankly, if anything in my lifetime or in a thousand years there would be no evidence, I still think string theory is correct, which is an opinion that I hear.

Then I get very worried about that. Every morning, when I come from my home to work—I live in Lexington—I pass near the mansion of Charles Ponzi. How did he get to buy this mansion?

[laughter]

Avi:  He basically told people, “If you give me your money, I’ll make more of it.” Irrespective of what the stock market does. That looked like a very appealing theory. It was a beautiful theory. Why not believe in it? People gave him the money. Then at some point, they started asking for it back. At that point, he was put in jail.

The way I see the scientific process of doing experiments is checking which theory is a Ponzi scheme. We put it to the test. The Ponzi idea was wonderful. Who would not like to believe it, but let’s see if it’s practical.

Whoever resists experimentation is basically maybe advocating something that is not real. Just like doctors make the Hippocratic Oath, physicists should make the Galilean Oath, which says that at least one idea that they work on will be tested during their lifetime.

Why do I say during their lifetime? You have to hold them accountable. If they say it will be tested in 200 years, they can get prizes and say, “Look, this theory is wonderful. It’s mathematically sophisticated.

By the way, we are the smartest physicists. And not only that, we are leading in physics.” They can say that. No problem, because we haven’t yet falsified it. By the way, we will not do that in the near future.

The learning experience that we are going through in science is founded on the interaction with nature. If we give up on that, we are losing the essence. It’s not just the detail. It’s the essence of the process.

Audience Member:  Your most favorite science fiction movies.

Avi:  Science fiction I don’t really like. I like science and I fiction separately.

[laughter]

Avi:  The problem with science fiction is that many times it violates the laws of physics. When I see a movie, a film, or read a book that violates the physics as I know it, it bothers me, so I cannot enjoy it aesthetically.

In terms of films, I do see them. I enjoy, for example, “Gravity” or “The Martian” more so than “Interstellar.” Some people argue that science fiction is really serving a very important purpose, because it expands our imagination. As long as that is not violating the laws of physics, I’m fine with it.

[laughter]

Benny:  I think we have time for one last question.

Audience Member:   Will, in my kid’s lifetime, there be commercial flights to space? Yes or no?

Avi:  Yes.

Audience Member:  Next one. The second question, it’s very hard to do science journalism. Do you have any tips on how to do it right?

Avi:  For example, nowadays, the scientific papers appear before publication on archives. Now, for example, I don’t need to make a press release. My papers are read by science journalists, and they get in touch with me whenever something is of interest.

As a science journalist, you have to figure out how to filter those papers that are, first, reliable and, second, interesting. If you have some knowledge of the field, it helps because you can judge for yourself.

Otherwise, you can get the advice of people or experts. You might ask someone, “What do you think about this?” Based on that, decide if it’s worth pursuing. It’s really important to show the way science is done and explain that under many circumstances, we have uncertainty in the process.

That’s what makes it exciting. Once we’ve figured something out, it should be celebrated. It should be a great, big celebration, because we figured something out. If most scientists say that climate is changing, that’s an exceptional and unusual situation.

Most of the time, scientists do not agree with each other. That should be made clear. Otherwise, if the public just sees the outcome, then the public doesn’t recognize the process.

I don’t think a scientific work is being detached from the regular human activity as being more noble or superior. Any person can be a scientist if you explain things well enough. Just like any person can be a plumber in principle.

Then it’s just natural to think about the world and try to figure it out. Unfortunately, after we go beyond a certain age, people tell us to stop asking questions. Some people pretend that they know more than they actually do.

That’s what muddies the water—people making claims that are not substantiated and not admitting mistakes when they are made. If we will all be honest, that would serve science better. It serves society better.

Base our conclusions on evidence. That should be the ultimate thing. We paid too much attention to people. We should pay more attention to evidence. That’s the important purpose of a science journalist to make it clear that it’s all about evidence and that we make progress.

Benny:  I think we’re out of time. If you have lingering questions, hopefully we might be able to stay around for a minute if people want to come up and ask. I just want to thank everyone here for coming along on this journey.

Avi:  My pleasure.

Benny:  Thank you so much for taking us to the edge of space and time. Thank you, Dr. Avi.

Avi:  Thank you.

[applause]

Audience Member:  What about UFOs?

[pause]

Avi:  If any of the earlier reports was right, we would have seen clear evidence for it, well above the scientific threshold of believability. The fact that it’s always on the borderline that it’s never clear means that either it’s military activity that tracks technology always.

If it’s humans doing it, it will always be on the borderline of being detectable if people are trying to hide it. Or it’s our imagination. It’s illusions. It’s something else. There is no reason that we are being monitored that we are not sufficiently interesting, too.

Also, I think that governments are not sufficiently competent to hide such things.

[laughter]

Audience Member:  You touched on the origin of life.