In this interview, Avi Loeb revisits traditional astrophysical concepts and the ongoing challenge scientists face in explaining the generation of the big bang due to the lack of a unifying theory between quantum mechanics and the known laws of gravity and spacetime. He suggests that such unification may have been achieved by civilizations that studied these phenomena for millennia, conducting highly advanced experiments on spacetime. He does not rule out the possibility that our universe is the result of such an experiment.
Loeb sees highly advanced civilizations as a close approximation to our age-old concept of a God at the origin of everything. Unlike religious beliefs, science will gradually allow us to verify the existence of advanced civilizations and collect supporting data, thanks to the advanced features of certain technosignatures in our atmosphere. In other words, the biblical burning bush, interpreted as divine in antiquity, would now be scrutinized by thermal cameras and numerous other instruments, including those designed to detect gravitational effects—this is the aim of the Galileo project.
The classification of civilization types by Russian astronomer Kardashev is based on the amount of energy civilizations use. Humanity currently utilizes only a ridiculously small fraction of the energy emitted by our sun. With Dyson spheres, other intelligences could capture and use a significant portion of a star's, galaxy's, or even more hypothetically, a universe's energy, enabling its expansion.
Loeb emphasizes that energy mastery is not the most crucial aspect; one must also consider the environmental modeling it enables and the creation of artificial intelligences. The envisioned ultimate step would be the creation of spacetime bubbles, allowing travel at speeds exceeding that of light, or the hypothetical creation of new "baby universes."
Regarding recent US disclosures about the study of numerous UAP reported by military personnel, Loeb discussed the matter with Director of National Intelligence Avril Haynes, also a physics graduate. Haynes stated that she did not know the true nature of these phenomena. Loeb recalled that his university is currently installing and deploying optical infrared and radio frequency automatic capture platforms as part of the Galileo project to solve this scientific mystery.
Similar to the analysis of the spherules from the interstellar object IM1 that fell into the sea, Loeb employs a strictly scientific method to support his conclusions. He believes that the majority of scientists' reluctance to address this topic is perfectly ridiculous.
Science must serve humanity without bias or preconceptions on such a fundamental question as the presence of non-human intelligences, without turning a blind eye as it currently does. In other words, science has been trying for decades to study highly hypothetical objects, such as dark matter, never detected, while refusing to examine the data on enigmatic phenomena seen by our radars and military sensors in space, on Earth, and in our seas.
Hopefully, we won't have to wait until the 22nd century for attitudes to finally evolve. Astronomers have written that the velocity data collected by the US Space Command must be erroneous because, otherwise, it would imply that the IM1 object is not composed of rocks and iron due to its excessively high resistance during entry into our atmosphere at very high velocity. For them, 95% of meteorites are rocks, and 5% are iron, and they persist in excluding other more exogenous compositions suggested by the abnormal resistance of the object.
Loeb believes that the data is correct and that we can trust the spatial surveillance performed by the Space Command for real-time detection of ballistic nuclear strikes targeting the USA. The detected velocity was higher than 95% of the objects cataloged in the solar system, and he thinks we won't learn anything if we continue to assume there are only "rocks" in the sky.
Stellar survival of the human species.
Regardless of the warming induced by our industrial activities, there will be an evaporation of our oceans within a billion years because Earth will move out of the habitable zone of the sun. It has been calculated that our planet has only 20% of its time remaining in this zone, raising the question of humanity's eventual stellar exodus. We certainly share this fate with billions of potentially inhabited worlds in our galaxy orbiting the same type of star as the Sun.
Thanks to evolution, simple living cells on Earth have gradually been replaced by multicellular organisms, including humans. Loeb thinks that we may be at an intermediate phase of life and intelligence evolution towards a more complete stellar resilience. Non-biological solutions are much more suitable for expansion millions of trillions of kilometers from Earth, such as AI that would allow for a new biological start on worlds selected specifically for the very long term.
For now, we have not yet succeeded in building self-repairing or self-replicating technologies. For an interstellar exodus, this goal will certainly need to be at least partially achieved to traverse thousands of light-years that separate us from our future destinations. It will be impossible to relay orders to exploration and reconnaissance probes, which must possess a high potential for decision-making artificial intelligence.
The biological form of intelligence will always be very vulnerable in the highly aggressive environment of the Cosmos, despite all the radiation protection that could be deployed. The human lifespan remains ridiculously short in the face of millennia of travel times, while temporal dilation at relativistic speeds poses other unresolved problems in terms of energy, trajectory correction, and protection against the slightest impact that could be catastrophic.
Initially, probes could be created to seed biological strains and plant seeds on candidate worlds, then retrieve the in-situ results for subsequent steps if positive. The establishment of human colonies on Mars would be possible, but it would not solve the problem of solar overheating and the eventual runaway of the Sun, which will impact even the giant gas planets Jupiter and Saturn.
In the scenario where no truly disruptive technology is developed, we would have to settle for available technology and choose, for example, to entrust just the DNA of our numerous forms of plant, animal, and human life to AIs, hoping they can adapt it to pristine distant worlds. Loeb takes the opportunity to make a beautiful metaphor with flowers that reproduce by scattering their seeds in the wind; humanity may have no other option but to do the same, but in a much more selective manner.
The challenge of the long-term survival of the human species will evidently be colossal. For Loeb, the prospect that other intelligences have already solved this problem could allow us to take a huge leap forward, especially in the case of recovering and reverse-engineering one of their advanced probes here on Earth. However, he emphasizes that the expansion of the Universe is accelerating, and extremely distant travel to other galaxies will be forever impossible on certain time and space scales, especially if the rate of this expansion approaches the speed of light.
He mentions the idea that clusters like the Virgo Cluster, where the star density is 100 times greater than that of the Milky Way, could serve as rallying points for advanced civilizations wanting to establish their genetic descendants in areas with high long-term survival potential. In these dense clusters, cosmic inflation would be significantly delayed, but the challenge is reaching them before they are definitely out of reach due to the accelerating expansion.
With the Sun, humanity seems to have made a poor choice for the long term: it will overheat and disappear in four billion years, well before dwarf stars, which are more stable and have a lifespan 100 times longer. However, planets orbiting dwarf stars have a much closer habitable zone, exposing them to dangerous coronal mass ejections capable of stripping their atmospheres. When these smaller stars have burned all their nuclear fuel in ten trillion years, there will presumably be no escape for anything.
However, at these astronomical time scales, the longevity of biological life is very uncertain anyway.
Chris Williamson, the interviewer, mentions one of his favorite hypotheses: the prolonged hibernation of an entire civilization when all the stars are extinguished and energy sources are depleted, leaving the nanoworld AIs to seek new solutions in the spacetime continuum and then awakening biological forms when a solution is found. Loeb explains the importance of expansion and multiplying the number of intelligent beings in a lineage to increase survival chances, including through scientific discoveries, and the need to seed life's ingredients in new worlds or even in new spacetime bubbles.
However, we do not know the percentage of civilizations that could reach such extraordinary scientific mastery, and probably many, limited by their intelligence or environmental conditions, will not succeed. Loeb points out that humanity spends hundreds of billions on military research to kill each other for simple political or religious reasons, while we are no longer in a context of immediate survival like our ancestors in a hostile jungle.
Cooperation between geopolitical powers, sharing resources, and scientific research efforts in a peaceful world would be much more beneficial for humanity. Instead, we have created the conditions for our immediate extinction, and this trap may have put an end to some other civilizations still confined to their home planet.
In this context, the discovery of other civilizations, much more resilient and peaceful, would be desirable and show us the example to follow. The lyrics of John Lennon's song "Imagine" seem to have not been sufficiently considered by our fellow beings. If, instead of wastefully depleting resources for the conquest of tiny portions of territory, we used the current military budget for interstellar exploration, according to Loeb's calculations, by the end of this century, we could send numerous exploration probes to the stars.
Prosperity in peace and cooperation is evidently much more advantageous than the senseless mutual destruction of state and political conflicts. Loeb hopes that one day, thousands of probes will traverse interstellar space in search of new opportunities to perpetuate our civilization. Many of them would eventually malfunction, but it would only take a few to find suitable planets to change the fate of humanity.
Asked about the difficulties of such a project, Loeb responds that recently, worms that had been frozen in Siberia's permafrost for 46,000 years were successfully brought back to life, and by developing current technologies, we could launch micro-probes toward nearby stars. In other words, the preliminary seeding of distant, life-friendly worlds is already within our reach.
Future
To anticipate a possible future extinction of humanity, we could send the building blocks of life that characterize us toward the stars, using solar sails for example. Researchers have demonstrated that some bacteria can survive planetary impacts within their meteorites, so a gentle deceleration of carrier probes upon reaching their destination may not be necessary.
The maneuver would currently take 15,000 years to reach the closest exoplanets, roughly the same time since humans left their original continent, Africa. A journey to the other end of the galaxy, on the other hand, would take a minimum of half a billion years based on known theoretical limitations, and with current human technologies, it would unfortunately take longer than the supposed age of the Universe, demonstrating the enormous challenge to overcome.
By developing ultra-precise targeting technologies, stabilizing a solar sail, and powerful lasers, one-fifth of the speed of light could be achieved in theory, allowing the journey to the nearest star in 25 years. If humanity could capture all the energy received from the Sun on Earth and reemit it as a powerful radio beam, humans could be sent in solar sail-equipped spacecraft to a nearby star. With a constant acceleration of one g, a speed close to that of light would be reached within a year, or 99% of that speed in 936 days, taking advantage of temporal dilations to reach enormous distances.
However, to decelerate, one would either have to politely ask a civilization on-site while sending them the deceleration beam plans and pointing parameters in advance, or rely on our own AIs sent 25,000 years earlier at low speed on-site to do the job, hoping none has a blue screen error like Microsoft's.... Obviously, it's not a guaranteed success, at least within the framework of our current knowledge and technologies.
In November 2023, a prototype of the EMdrive was launched into orbit to test its potential for producing thrust without mass ejection; the actual thrust measurements will be known in 2024. For now, a disruptive solution to the problem of space travel remains to be discovered, and it is no secret that some of us rely on the civilian sensors of the Galileo project, tracking UAP, or the LIGO interferometer and other scientific sensors to help us....
