The Diary Of A CEO

World-Renowned Physicist: The Truth About Aliens! UFOs Are Definitely Robotic - Michio Kaku

with Michio Kaku
21 May 2026 19 min read 2h 5m
TL;DR

Michio Kaku argues that while extraterrestrial life almost certainly exists given 100 billion stars in our galaxy, actual alien visitation to Earth remains unproven—we're stuck at close encounters of the first kind with no tangible evidence. He explores how immortality could be physically possible through telomerase technology, warns of humanity's existential risks from nuclear weapons and AI, and explains string theory as the foundation for understanding everything from black holes to parallel universes.

Key Moments
Michio Kaku
“we know that there's a clock in our body called the tie that tracks how long we're going to live and there's something called talomeorase which stops the clock which means that we can live forever. That's the good news. But the bad news was we found out that cancer also uses tie and talomeorase to live forever.”
Discussing the scientific possibility of human immortality within the laws of physics and biology
▶ 0:07
Michio Kaku
“A Saturn 5 rocket would take 70,000 years just to reach the nearest star. Hop, skip, and a jump. 70,000 years. So a civilization that could reach the earth would be hundreds thousands of years more advanced than us.”
Explaining the massive distance barriers that would need to be overcome for alien visitation to be physically feasible
▶ 6:31
Michio Kaku
“95% of the sightings we can we can uh explain using the known laws of physics. 5% are either optical illusions or they are evidence of visitation. You can't rule it out.”
Responding to whether UFO sightings constitute proof of extraterrestrial visitation
▶ 8:57
Michio Kaku
“String theory says that what is a proton? What is an electron? They're nothing but vibrations of a string. So from a distance, this looks like a point particle. From a distance, this is an electron. But if you could magnify that, we find out it's not really a point at all. It's really a vibrating string.”
Explaining the fundamental nature of matter and particles according to string theory
▶ 15:52
Michio Kaku
“the universe is based on probabilities. Probabilities that uranium will fire for example which gives us nuclear weapons. probability that hydrogen can fuse and that gives us stars. So the universe is based on probabilities not on simulations.”
Arguing against simulation theory by pointing to the quantum mechanical foundations of reality
▶ 33:10
About Michio Kaku
›
Michio Kaku is a world-renowned theoretical physicist and futurist who has spent 71 years studying physics and the universe, beginning at age 8 after learning about Einstein's death. He pioneered string field theory, one of the branches of string theory, and continues to work on Einstein's dream of a unified "theory of everything." Kaku is known for making complex physics accessible to mainstream audiences through books, interviews, and media appearances exploring topics from immortality and AI to extraterrestrial life and the multiverse.
Takeaways
1
Alien life likely exists, but visiting us remains implausible With 100 billion stars in our galaxy and roughly 10% having Earth-like planets, the probability of life existing elsewhere is nearly 100%. However, the physics of interstellar travel—a 70,000-year journey to the nearest star with current rockets—means any visiting civilization would need to be hundreds of thousands of years more advanced and master space-warping technology that remains theoretical.
2
String theory unifies all particles as vibrating strings Rather than treating hundreds of discovered subatomic particles as separate entities, string theory proposes they are all different vibrational modes of a single fundamental string. This elegantly explains why nature has so many particle types and forms the foundation for a unified "theory of everything" that explains physics from quantum mechanics to gravity.
3
Immortality is scientifically possible but comes with cancer risk Telomerase, an enzyme that resets the biological clock (telomeres) limiting cell division, could theoretically enable infinite human lifespan within the laws of physics and biology. The critical challenge is applying this selectively to prevent cancer, which itself exploits telomerase for unlimited replication—making the engineering problem, not the physics, the barrier to practical immortality.