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Here's how to prove that you are a simulation and nothing is real
How do you know you are real? A classic paper by philosopher Nick Bostrom argues you are likely a simulation.

- Philosopher Nick Bostrom argues that humans are likely computer simulations in the "Simulation Hypothesis".
- Bostrom thinks advanced civilizations of posthumans will have technology to simulate their ancestors.
- Elon Musk and others support this idea.
Are we living in a computer-driven simulation? That seems like an impossible hypothesis to prove. But let's just look at how impossible that really is.
For some machine to be able to conjure up our whole reality, it needs to be amazingly powerful, able to keep track of an incalculable number of variables. Consider the course of just one human lifetime, with all of the events it entails, all the materials, ideas and people that one interacts with throughout an average lifespan. Then multiply that by about a hundred billion souls that have graced this planet with their presence so far. The interactions between all these people, as well as the interactions between all the animals, plants, bacterium, planetary bodies, really all the elements we know and don't know to be a part of this world, is what constitutes the reality you encounter today.
Composing all that would require coordinating an almost unimaginable amount of data. Yet, it's just "almost" inconceivable. The fact that we can actually right now in this article attempt to come up with this number is what makes it potentially possible.
So how much data are we talking about? And how would such a machine work?
In 2003, the Swedish philosopher Nick Bostrom, who teaches at University of Oxford, wrote an influential paper on the subject called "Are you living in a computer simulation" that tackles just this subject.
In the paper, Bostrom argues that future people will likely have super-powerful computers on which they could run simulations of their "forebears". These simulations would be so good that the simulated people would think they are conscious. In that case, it's likely that we are among such "simulated minds" rather than "the original biological ones."
In fact, if we don't believe we are simulations, concludes Bostrom, then "we are not entitled to believe that we will have descendants who will run lots of such simulations of their forebears." If you accept one premise (that you'll have powerful super-computing descendants), you have to accept the other (you are simulation).
That's pretty heavy stuff. How to unpack it?
As he goes into the details of his argument, Bostrom writes that within the philosophy of mind, it is possible to conjecture that an artificially-created system could be made to have "conscious experiences" as long as it is equipped with "the right sort of computational structures and processes." It's presumptuous to assume that only experiences within "a carbon‐based biological neural networks inside a cranium" (your head) can gives rise to consciousness. Silicon processors in a computer can be potentially made to mimic the same thing.
Of course, at this point in time this isn't something our computers can do. But we can imagine that the current rate of progress and what we know of the constraints imposed by physical laws can lead to civilizations able to come up with such machines, even turning planets and stars into giant computers. These could be quantum or nuclear but whatever they would be, they could probably run amazingly detailed simulations.
In fact, there is number to represent the kind of power needed to emulate a human brain's functionality, which Bostrom gives as ranging from 1014 to 1017 operations per second. If you hit that kind of computer speed, you can run a reasonable enough human mind within the machine.
Simulating the whole universe, including all the details "down to the quantum level" requires more computing oomph, to the point that it may be "unfeasible," thinks Bostrom. But that may not really be necessary as all the future humans or post-humans would need to do is to simulate the human experience of the universe. They'd just need to make sure the simulated minds don't pick up on anything that doesn't look consistent or "irregularities". You wouldn't have to recreate things the human mind wouldn't ordinarily notice, like things happening at the microscopic level.
Representing the goings on among distant planetary bodies could also be compressed - no need to get into amazing detail among those, certainly not at this point. The machines just need to do a good enough job. As they would keep track of what all the simulated minds believe, they could just fill in the necessary details on demand. They could also edit out any errors if those happen to take place.
Bostrom even provides a number for simulating all of human history, which he puts at around ~1033 ‐ 1036 operations. That would be the goal for the sophisticated enough virtual reality program based on what we already know about their workings. In fact, it's likely just one computer with a mass of a planet can pull off such a task "by using less than one millionth of its processing power for one second," thinks the philosopher. A highly advanced future civilization could build a countless number of such machines.
What could counter such a proposal? Bostrom considers in his paper the possibility that humanity will destroy itself or be destroyed by an outside event like a giant meteor before it reaches this post-human simulated stage. There are actually many ways in which humanity could always be stuck in the primitive stages and not ever be able to create the hypothetical computers needed to simulate entire minds. He even allows for the possibility of our civilization becoming extinct courtesy of human-created self-replicating nanorobots which turn into "mechanical bacteria".
Another point against us living in a simulation would be that future posthumans might not care to or be allowed to run such programs at all. Why do it? What's the upside of creating "ancestor simulations"? He thinks that it's not likely the practice of running such simulations would be so widely assumed to be immoral that it would be banned everywhere. Also, knowing human nature, it's unlikely that there wouldn't be someone in the future who would not find such a project interesting. This is the kind of stuff we would do today if we could and chances are, we would continue to want to do in the far distant future.
"Unless we are now living in a simulation, our descendants will almost certainly never run an ancestor‐simulation," writes Bostrom.
A fascinating outcome of all this speculation is that we have no way of knowing what the true reality of existence really is. Our minds are likely accessing just a small fraction of the "totality of physical existence." What we think we are may be run on virtual machines that are run on other virtual machines - it's like a nesting doll of simulations, making it nearly impossible for us to see beyond to the true nature of things. Even the posthumans simulating us could be themselves simulated. As such, there could be many levels of reality, concludes Bostrom. The future us might likely never know if they are at the "fundamental" or "basement" level.
Interestingly, this uncertainty gives rise to universal ethics. If you don't know you are the original, you better behave or the godlike beings above you will intervene.
What are other implications of these lines of reasoning? Ok, let's assume we are living in a simulation – now what? Bostrom doesn't think our behavior should be affected much, even with such heavy knowledge, especially as we don't know the true motivations of future humans behind creating the simulated minds. They might have entirely different value systems.
If you think this proposal sounds plausible, you would not be alone. Elon Musk and many others are fairly convinced we are just sophisticated self-aware computer programs or maybe even video games.
You can take the plunge and read the full paper by Nick Bostrom for yourself here.
Check out Nick Bostrom’s TED talk on superintelligencies:
- Is There Evidence That We're Living in a Computer Simulation? - Big ... ›
- 3 arguments why we live in a matrix and 3 arguments that refute ... ›
- There's a 20% Chance We're All Sims. - Big Think ›
- New hypothesis argues the universe simulates itself into existence - Big Think ›
- New hypothesis argues the universe simulates itself into existence - Big Think ›
- Are we living in a simulation? - Big Think ›
There are 5 eras in the universe's lifecycle. Right now, we're in the second era.
Astronomers find these five chapters to be a handy way of conceiving the universe's incredibly long lifespan.
Image based on logarithmic maps of the Universe put together by Princeton University researchers, and images produced by NASA based on observations made by their telescopes and roving spacecraft
- We're in the middle, or thereabouts, of the universe's Stelliferous era.
- If you think there's a lot going on out there now, the first era's drama makes things these days look pretty calm.
- Scientists attempt to understand the past and present by bringing together the last couple of centuries' major schools of thought.
The 5 eras of the universe
<p>There are many ways to consider and discuss the past, present, and future of the universe, but one in particular has caught the fancy of many astronomers. First published in 1999 in their book <a href="https://amzn.to/2wFQLiL" target="_blank"><em>The Five Ages of the Universe: Inside the Physics of Eternity</em></a>, <a href="https://en.wikipedia.org/wiki/Fred_Adams" target="_blank">Fred Adams</a> and <a href="https://en.wikipedia.org/wiki/Gregory_P._Laughlin" target="_blank">Gregory Laughlin</a> divided the universe's life story into five eras:</p><ul><li>Primordial era</li><li>Stellferous era</li><li>Degenerate era</li><li>Black Hole Era</li><li>Dark era</li></ul><p>The book was last updated according to current scientific understandings in 2013.</p><p>It's worth noting that not everyone is a subscriber to the book's structure. Popular astrophysics writer <a href="https://www.forbes.com/sites/ethansiegel/#30921c93683e" target="_blank">Ethan C. Siegel</a>, for example, published an article on <a href="https://www.forbes.com/sites/startswithabang/2019/07/26/we-have-already-entered-the-sixth-and-final-era-of-our-universe/#7072d52d4e5d" target="_blank"><em>Medium</em></a> last June called "We Have Already Entered The Sixth And Final Era Of Our Universe." Nonetheless, many astronomers find the quintet a useful way of discuss such an extraordinarily vast amount of time.</p>The Primordial era
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkwMTEyMi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNjEzMjY1OX0.PRpvAoa99qwsDNprDme9tBWDim6mS7Mjx6IwF60fSN8/img.jpg?width=980" id="db4eb" class="rm-shortcode" data-rm-shortcode-id="0e568b0cc12ed624bb8d7e5ff45882bd" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="1049" />Image source: Sagittarius Production/Shutterstock
<p> This is where the universe begins, though what came before it and where it came from are certainly still up for discussion. It begins at the Big Bang about 13.8 billion years ago. </p><p> For the first little, and we mean <em>very</em> little, bit of time, spacetime and the laws of physics are thought not yet to have existed. That weird, unknowable interval is the <a href="https://www.universeadventure.org/eras/era1-plankepoch.htm" target="_blank">Planck Epoch</a> that lasted for 10<sup>-44</sup> seconds, or 10 million of a trillion of a trillion of a trillionth of a second. Much of what we currently believe about the Planck Epoch eras is theoretical, based largely on a hybrid of general-relativity and quantum theories called quantum gravity. And it's all subject to revision. </p><p> That having been said, within a second after the Big Bang finished Big Banging, inflation began, a sudden ballooning of the universe into 100 trillion trillion times its original size. </p><p> Within minutes, the plasma began cooling, and subatomic particles began to form and stick together. In the 20 minutes after the Big Bang, atoms started forming in the super-hot, fusion-fired universe. Cooling proceeded apace, leaving us with a universe containing mostly 75% hydrogen and 25% helium, similar to that we see in the Sun today. Electrons gobbled up photons, leaving the universe opaque. </p><p> About 380,000 years after the Big Bang, the universe had cooled enough that the first stable atoms capable of surviving began forming. With electrons thus occupied in atoms, photons were released as the background glow that astronomers detect today as cosmic background radiation. </p><p> Inflation is believed to have happened due to the remarkable overall consistency astronomers measure in cosmic background radiation. Astronomer <a href="https://www.youtube.com/watch?v=IGCVTSQw7WU" target="_blank">Phil Plait</a> suggests that inflation was like pulling on a bedsheet, suddenly pulling the universe's energy smooth. The smaller irregularities that survived eventually enlarged, pooling in denser areas of energy that served as seeds for star formation—their gravity pulled in dark matter and matter that eventually coalesced into the first stars. </p>The Stelliferous era
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkwMTEzNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxMjA0OTcwMn0.GVCCFbBSsPdA1kciHivFfWlegOfKfXUfEtFKEF3otQg/img.jpg?width=980" id="bc650" class="rm-shortcode" data-rm-shortcode-id="c8f86bf160ecdea6b330f818447393cd" data-rm-shortcode-name="rebelmouse-image" data-width="481" data-height="720" />Image source: Casey Horner/unsplash
<p>The era we know, the age of stars, in which most matter existing in the universe takes the form of stars and galaxies during this active period. </p><p>A star is formed when a gas pocket becomes denser and denser until it, and matter nearby, collapse in on itself, producing enough heat to trigger nuclear fusion in its core, the source of most of the universe's energy now. The first stars were immense, eventually exploding as supernovas, forming many more, smaller stars. These coalesced, thanks to gravity, into galaxies.</p><p>One axiom of the Stelliferous era is that the bigger the star, the more quickly it burns through its energy, and then dies, typically in just a couple of million years. Smaller stars that consume energy more slowly stay active longer. In any event, stars — and galaxies — are coming and going all the time in this era, burning out and colliding.</p><p>Scientists predict that our Milky Way galaxy, for example, will crash into and combine with the neighboring Andromeda galaxy in about 4 billion years to form a new one astronomers are calling the Milkomeda galaxy.</p><p>Our solar system may actually survive that merger, amazingly, but don't get too complacent. About a billion years later, the Sun will start running out of hydrogen and begin enlarging into its red giant phase, eventually subsuming Earth and its companions, before shrining down to a white dwarf star.</p>The Degenerate era
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkwMTE1MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxNTk3NDQyN30.gy4__ALBQrdbdm-byW5gQoaGNvFTuxP5KLYxEMBImNc/img.jpg?width=980" id="77f72" class="rm-shortcode" data-rm-shortcode-id="08bb56ea9fde2cee02d63ed472d79ca3" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="810" />Image source: Diego Barucco/Shutterstock/Big Think
<p>Next up is the Degenerate era, which will begin about 1 quintillion years after the Big Bang, and last until 1 duodecillion after it. This is the period during which the remains of stars we see today will dominate the universe. Were we to look up — we'll assuredly be outta here long before then — we'd see a much darker sky with just a handful of dim pinpoints of light remaining: <a href="https://earthsky.org/space/evaporating-giant-exoplanet-white-dwarf-star" target="_blank">white dwarfs</a>, <a href="https://earthsky.org/space/new-observations-where-stars-end-and-brown-dwarfs-begin" target="_blank">brown dwarfs</a>, and <a href="https://earthsky.org/astronomy-essentials/definition-what-is-a-neutron-star" target="_blank">neutron stars</a>. These"degenerate stars" are much cooler and less light-emitting than what we see up there now. Occasionally, star corpses will pair off into orbital death spirals that result in a brief flash of energy as they collide, and their combined mass may become low-wattage stars that will last for a little while in cosmic-timescale terms. But mostly the skies will be be bereft of light in the visible spectrum.</p><p>During this era, small brown dwarfs will wind up holding most of the available hydrogen, and black holes will grow and grow and grow, fed on stellar remains. With so little hydrogen around for the formation of new stars, the universe will grow duller and duller, colder and colder.</p><p>And then the protons, having been around since the beginning of the universe will start dying off, dissolving matter, leaving behind a universe of subatomic particles, unclaimed radiation…and black holes.</p>The Black Hole era
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkwMTE2MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMjE0OTQ2MX0.ifwOQJgU0uItiSRg9z8IxFD9jmfXlfrw6Jc1y-22FuQ/img.jpg?width=980" id="103ea" class="rm-shortcode" data-rm-shortcode-id="f0e6a71dacf95ee780dd7a1eadde288d" data-rm-shortcode-name="rebelmouse-image" data-width="1400" data-height="787" />Image source: Vadim Sadovski/Shutterstock/Big Think
<p> For a considerable length of time, black holes will dominate the universe, pulling in what mass and energy still remain. </p><p> Eventually, though, black holes evaporate, albeit super-slowly, leaking small bits of their contents as they do. Plait estimates that a small black hole 50 times the mass of the sun would take about 10<sup>68</sup> years to dissipate. A massive one? A 1 followed by 92 zeros. </p><p> When a black hole finally drips to its last drop, a small pop of light occurs letting out some of the only remaining energy in the universe. At that point, at 10<sup>92</sup>, the universe will be pretty much history, containing only low-energy, very weak subatomic particles and photons. </p>The Dark Era
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMjkwMTE5NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0Mzg5OTEyMH0.AwiPRGJlGIcQjjSoRLi6V3g5klRYtxQJIpHFgZdZkuo/img.jpg?width=980" id="60c77" class="rm-shortcode" data-rm-shortcode-id="7a857fb7f0d85cf4a248dbb3350a6e1c" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="810" />Image source: Big Think
<p>We can sum this up pretty easily. Lights out. Forever.</p>Dark energy: The apocalyptic wild card of the universe
Dr. Katie Mack explains what dark energy is and two ways it could one day destroy the universe.
- The universe is expanding faster and faster. Whether this acceleration will end in a Big Rip or will reverse and contract into a Big Crunch is not yet understood, and neither is the invisible force causing that expansion: dark energy.
- Physicist Dr. Katie Mack explains the difference between dark matter, dark energy, and phantom dark energy, and shares what scientists think the mysterious force is, its effect on space, and how, billions of years from now, it could cause peak cosmic destruction.
- The Big Rip seems more probable than a Big Crunch at this point in time, but scientists still have much to learn before they can determine the ultimate fate of the universe. "If we figure out what [dark energy is] doing, if we figure out what it's made of, how it's going to change in the future, then we will have a much better idea for how the universe will end," says Mack.
Astrophysicists find unique "hot Jupiter" planet without clouds
A unique exoplanet without clouds or haze was found by astrophysicists from Harvard and Smithsonian.
Illustration of WASP-62b, the Jupiter-like planet without clouds or haze in its atmosphere.
- Astronomers from Harvard and Smithsonian find a very rare "hot Jupiter" exoplanet without clouds or haze.
- Such planets were formed differently from others and offer unique research opportunities.
- Only one other such exoplanet was found previously.
Munazza Alam – a graduate student at the Center for Astrophysics | Harvard & Smithsonian.
Credit: Jackie Faherty
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