Humanity will ‘probably’ survive past 21st century, says Cambridge astrophysicist Lord Rees

Lord Martin Rees, the Astronomer Royal and Cambridge astrophysicist, said he thinks humanity will get past the end of the 21st century but is “not very optimistic” due to the impact of technology and our use of resources.

He was speaking during a wide-ranging interview for the Lord Speaker’s corner, during which he also spoke about the risks of AI, said he “hoped” billionaire-bankrolled labs seeking to extend human lifespan in a “big way” failed, and argued that governments should no longer fund human space travel.

Lord Rees, emeritus professor of Cosmology and Astrophysics at the University of Cambridge, and co-founder of The Cambridge Centre for the Study of Existential Risk (CSER), was asked by the Lord Speaker if humanity will survive beyond the end of the century.

He said “I think we will certainly have a bumpy ride, but I think we will still be there. You can imagine scenarios that wipe everything out, but I think we’ll still be there. But the reason I’m not very optimistic is that we are more empowered by technology than we ever were. And one species, named the human species, is having an effect on the rest of the natural world in a way it never did in the past because there are now eight billion of us and we’re all more empowered by technology and we use more energy and use more resources.

“And so we are depleting natural capital as it were, and there’s a risk that we will leave for our descendants a depleted world with mass extinction. I think it’s an ethical imperative that we should change our policies so that just as we benefit from the heritage of centuries past, we leave a positive heritage for the future.”

He continued: “The other thing I worry about is that new technologies are so powerful that even a few people – a few dissidents or a dissident group – can cause some kind of accident, which could cascade globally, massive cyber-attacks, which can knock out the electricity grid in a large region. And of course that will lead to social disruption in a few days.

“These things can spread globally in our world, which is interconnected in a way it never was in previous centuries. And so I think we are vulnerable to classes of catastrophe, which are not just local but can spread globally.

“Covid-19 spread globally as we know, and any other pandemic would spread globally and even worse than the prospect of future pandemics, which could be more virulent and more transmissible than Covid-19, is in my view, the possibility that people with evil intent might engineer more dangerous viruses because it’s possible by a technique called gain of function to make viruses more virulent and transmissible than the natural variants.

“If that can be done and that leaks out by error or by design, that could cause an even worse pandemic than the natural ones.”

He also warned that the growth of AI and complicated technological networks leaves us vulnerable to “bugs”.

“If we become overdependent, then that of course will cause a catastrophe. It may cause the electric grid to break down. We had a mini version quite recently when the air traffic control system broke down because of some bug or some incorrect entry into a system. And so these systems are so complicated and so interconnected that I think we’re going to be very lucky if we can escape severe setbacks of this kind,” he said.

He warned that one individual could be responsible.

“We know that lone wolves can carry out cyber-attacks and we may get to the stage when some biologist can, as it were, play God on the kitchen table and make some new variant of a virus, which is very, very dangerous.

“You can’t build a nuclear weapon in your back garden. It needs big facilities and they can be monitored globally as we know by the International Atomic Energy Agency. But if someone really wants to make a dangerous pathogen, then they could do it in an existing lab or maybe in a private lab that no knows about.”

Lord Rees, a former master of Trinity College, has advocated for the establishment of supranational institutions to fight global challenges, like climate change, and apply regulatory frameworks. And that should apply to artificial intelligence, he told the Lord Speaker.

“I think the special problem of AI is that the main players are now multinational conglomerates as we know, which are dominating the world’s market. And it’s very hard to tax these companies properly and for the same reasons can be very hard to enforce regulations on them. But we’ve got to try,” he said.

Tackling climate change, meanwhile, will mean ensuring the ‘global south’ can leapfrog on to what richer countries in the north learn from the drive towards net zero, he argued.

“By 2050 there’ll be four billion people in the global south. They’ll need more energy per capita, and it’ll be no good if we in the north have achieved net zero if at the same time by 2050 the global south is producing as much CO2 as we in the north are today,” he said. “It’s rather like they all leapfrog directly to mobile phones never having had landlines throughout Africa.”

Those hoping to set off into space to avoid Earth’s problems are living under an illusion, he suggested, arguing billionaire Elon Musk’s suggestion that humans could live on the moon or Mars was foolhardy.

“I think there might be a few crazy pioneers living on Mars, just like there are people living at the South Pole, although it’s far less hospitable than the South Pole, but the idea of mass migration to avoid the Earth’s problems, which he and a few other space enthusiasts adopt, that I think is a dangerous illusion,” he said.

“I don’t think it’s realistic and we’ve got to solve those problems here on earth. Dealing with climate change on Earth is a doddle compared to making Mars habitable. So I don’t think we should hold that out as a long-term aim at all.”

Other billionaires are trying to extend human lifespan in “a big way”, and he had a word of caution for them.

“There are three labs – two in California and one actually in Cambridge, called Altos Labs – which are bankrolled by billionaires, who want to extend their lifespan and live much longer. And I rather hope they won’t succeed because this would be a fundamental new kind of inequality,” said Lord Rees.

“The way I would see it is that these billionaires, when they were young, they wanted to be rich, now they’re rich, they want to be young again, and that’s not quite so easy to arrange.”

One thing he would be keener for billionaires to fund – so that governments do not – is human space flight.

“I’m sceptical about the idea of a human space flight being worthwhile,” he said.

“Robots can do all the practical things, assembling big structures in space and exploring the surface of Mars and all that. If humans want to fly into space as an adventure, then perhaps they can be supported by sponsorship or the billionaires.”

And, for the record, he agreed there “probably is some kind of life out there, a long way away on a planet orbiting other stars”.

“I think it’s probably something unrecognisably different,” he said.