As a cosmologist, I often carry around a universe or two in my pocket. Not entire, infinitely large universes, but maybe a few billion light years or so across. Enough to be interesting.
Of course, these are not “real” universes; rather they are universes I have simulated on a computer.
The basic idea of simulating a universe is quite simple. You need “initial conditions” which, for me, is the state of the universe just after the Big Bang.
To this, you add the laws of physics, such as: how gravity pulls on mass, how gas flows into galaxies, and how stars are born, live and die.
You press “go”, and then sit back as the computer calculates all of the complex interactions, and evolves the universe over cosmic time. The video below gives a good introduction:
What’s more fun is playing “Master of the Universe”, and messing about with the laws of physics, such as changing the properties of gravity, or how black holes swallow matter. Waiting to see the outcome of these mutated universes is always interesting.
I know in my heart that these universes are nothing more than ones and zeros buried within my computer, but in the movies I make of my evolving galaxies and clusters, and the one embedded further down in this article, I can see the mass moving around. It looks real!
Computer simulations of complex phenomena are everywhere in science, and cosmologists aren’t the only ones that marvel at synthetic chunks of the real universe.
It is equally inspiring to watch the flow of air around a newly-designed wing (see video below), or how individual molecules make their way through a biological membrane, and such simulations have revolutionised science.
Of course, these advances have only occurred with the growth of computer power over the last few decades, and the push is always towards the inclusion of more complex physics over an immense range of scales, from the cosmological to the quantum.
We are always limited by the power of computing, but as computers get bigger and faster, so does the detail within our synthetic universes.
But let’s imagine a time in the future, a time when computers are powerful enough to fully simulate a human brain, with its vast array of interconnected neurons.
These neurons obey the laws of physics, and fire as their chemical balances change. Thoughts would echo around this synthetic brain, with electrical signals coursing backwards and forwards.
Not being a philosopher, I will ignore the (seemingly endless) debates about free will and consciousness, but if you take a purely mechanical view of the human brain, the synthetic brain will be as “alive” as the organic brain that made it.
Fed with the stimulus from a synthetic body interacting with a synthetic universe, it will experience pain and fear, happiness and love, even boredom and drowsiness.
There are, in fact, some that believe we will all be reborn in a glorious future, where computers are powerful enough to recreate everyone who has ever lived, and then sustain them for eternity.
While this vision of heaven is touted as the Final Anthropic Principle, some have more bluntly labelled it the “Completely Ridiculous Anthropic Principle”, or C.R.A.P. for short.
But we may not have to wait until the distant future!
To quote the late, great Douglas Adams, “there is another theory which states that this has already happened”.
Not that someone on Earth, or even within our universe, has created a truly synthetic universe, complete with beings that are clueless to the fact they are nothing but part of a computer experiment.
No, the startling realisation is that we, our very existence, every thing we have seen, have experienced, or will ever experience, could be nothing but the chugging of bits in an unimaginable supercomputer.
As I type this on a laptop, and stare out the train window at the station rolling past, at the people, the trees, the dirt on the ground, surely I would know if I was part of a computer program?
But then again, my brain is simply processing inputs, and if the simulated inputs fed into my simulated brain are good enough, how would I know?
It is important to remember that this picture is different to the “Brain-in-a-vat” presented in the Matrix movies. There, an organic brain is fed information, recreating the synthetic world in which the characters find themselves.
Instead, our picture is that there is no organic brain. We are part of the matrix itself.
So, how can we know if we are part of a computer simulation?
It is important to remember our earthly computers are limited in the way they can represent real numbers, holding only a finite number of digits for typical calculations.
What this means is that my simulated universes are quantised in some sense, with the limited resolution imprinted in the details of the structure that is produced.
If we are living in a computer simulation, then maybe such resolution effects are apparent to us. Our world doesn’t look like the Minecraft universe (see video below), and so we expect the resolution scale to be smaller than the scale of individual atoms, rather than large, foot-cubed blocks.
Just last month, researchers from the University of Bonn, Germany suggested we can detect such “chunkiness” of the small scale by looking how high-energy particles, known as cosmic rays, traverse huge distances in the universe. As these rays bounce through this space, their energy properties get modified, and by looking at what arrives on Earth, we can work out the size of the chunks.
But there are problems with this idea.
Firstly, we are working under the assumption that the computer we live in operates like an everyday computer. But these everyday computers are governed by the laws of physics of the synthetic universe in which we reside.
The unimaginably powerful computer that hosts our universe may operate in ways we cannot even think about.
Another problem is that those trying to understand the nature of the very small have already proposed a quantised backdrop of space and time in which we live.
Is the existence of such a space-time simply a property of a real universe, or the tell-tale sign of a synthetic one? How can we ever tell them apart? Do we even want to?
One way of potentially detecting the real nature of the universe is to search for the extraordinary – or, in the words of my children, who play videogames, glitches – where the program doesn’t do as expected.
Perhaps some of the unexplained things we cannot yet explain are simply glitches in the program (although I am a fan of illusionist Derren Brown and think the human mind can be easily tricked).
The other alternative is more drastic.
When my synthetic universes are running, they can abruptly come to a halt for a variety of reasons, such as disk-space filling up, errors in the memory, or something as simple as the cleaner unplugging the computer to vacuum the floor.
If my synthetic universe is running when the power goes out, it simply ceases to exist.
I do hope the cleaners of our potential-hyperdimensional-universe-simulating overlords are more careful.
Further reading:
- The measurement that would reveal the universe as a supercomputer simulation – Technology Review
Mark King
Senior Lecturer, Psychology and Counselling and Researcher, CARRSQ at Queensland University of Technology
I've always found it fascinating that physics is seen as the "hard" end of science, psychology as the "soft" end, and disciplines like philosophy even further away, yet theorisation of this sort in physics comes right back to the highly speculative "what if" questions that are more familiar among philosophers and science fiction writers. This is where a familiarity with longstanding philosophical debates would be useful - the highly solipsistic nature of the speculations in this article would probably attract rather severe marks in an undergraduate philosophy essay, even though they're entertaining.
Geraint Lewis
Professor of Astrophysics at University of Sydney
Are you saying that asking "what if" questions is solely the realm of philosophers? That's precisely what us physicists do every day. As for getting severe marks in a philosophy essay - that why I stuck with physics.
Geoffrey Edwards
logged in via email @gmail.com
"Are you saying that asking "what if" questions is solely the realm of philosophers?"
If you read what Mark is saying you will see that this is obviously not the case. It is interesting that many in the so called "hard sciences" are willing to denigrate philosophy while engaging in exactly the type of speculative enterprise that Philosophers have long been engaged in.
What you are doing here is metaphysics. Plain and simple. What is the underlying nature of our reality? What is the "real" world? Is this world as it appears to us, in some sense NOT "real"?
Questions addressed by every philosopher of note since Plato.
Descartes gave us more than just cartesian co-ordinates. He also gave us cartesian scepticism and the "Evil Genius" - and he didn't ignore consciousness.
But, apparently, as you bailed on philosophy because of "severe marks" you may have missed that.
Russell Daylight
Lecturer in English
Greaint, you brought this on yourself with an unnecessary slur on philosophy. Your article is absolutely harmless, if tending towards the solipsistic, but apparently ignorant of 2 millenia of metaphysics.
Why must scientists always throw an anti-humanities aside into their articles? Like Dawkins and Pinker, so many scientists feel compelled to express resentment and contempt for their colleagues in other faculties.
Yuri Pannikin
Director
Perhaps because Dawkins and Pinker et al are fed up with the poorly constructed and inane nonsense that emanates, at times, from the humanities.
Kim Peart
Researcher & Writer
Rather than blowing out dark clouds of nitrous oxide indignations, it would be a marvel if them with a philosophical bent could park the speech box in The Conversation and actually add to the discussion, in plain English.
Then we mortals may be led to a clearer understanding of the maze created to lure the unwary ever deeper into unknown thinking parts.
Considering that the whole bleeding society has totally failed to keep a safe Earth, philosophers must carry their share of collective guilt and begin to make amends, demonstrating how compassion may assure human survival by leading to a stellar economy without poverty.
If philosophy is unable to assure our survival and help deliver a prosperous future, we may all be doomed to a black hole of remorseless heat waves.
Kim Peart
Fred Pribac
logged in via email @internode.on.net
Oh for heavens sake! These arts versus sciences arguments are just plain silly!
If "The Conversation" comment streams can have every Tom, Dick and Harriet non-scientist under the sun challenging climate science findings why can't we have a philosophy newby or two giving us their two bobs worth of rudimentary metaphysics?
It's all good fun ... at least until somone loses a planet!
Geoffrey Edwards
logged in via email @gmail.com
"It's all good fun ... at least until somone loses a planet!"
Well, when science can explain why losing the planet should be considered a bad thing, I am sure the Philosophy n00bs will be happy to pay attention.
Fred Pribac
logged in via email @internode.on.net
Huh? What's the beef here?
"Well, when science can explain why losing the planet should be considered a bad thing, I am sure the Philosophy n00bs will be happy to pay attention."
Alex Cannara
logged in via Facebook
Real or 'simulated' -- simulators are real things -- this silly topic has already, and will continue to waste, real power in the real universe, adding to all our nasty problems, like climate change, ocean rise & acidification, etc.
To paraphrase a famous movie line -- simulate that!
Geraint Lewis
Professor of Astrophysics at University of Sydney
Do you really think that simulating things is a waste of time and energy? These are not done just for the fun of it, but to understand the universe and how it works. My colleagues study how high-energy radiations travel through bodies, so you can work out how to cure cancers, and planes and cars are designed as simulations (and optimized before a piece of metal is shaped). The list is endless.
Even the climate change you mention is understood through vast computer simulations of the atmosphere. All "modelled" systems are simulations.
Roy Niles
logged in via Facebook
@geraint Lewis: 'All "modelled" systems are simulations.'
And they all have simulators (and some apparently human ones to boot) that simulate them, right?. Are these simulators choice makers, or were they also simulated determinatively? Were there any choice makers back down the line that made their own? If so, did they they choose from an indeterminate universe that needed choices to determine a perfectly predictable future that needed none?
Or could all simulations have come from a determinate series of past universes, no choices ever being made, no accidents ever having happened that were ever accidental? And was there ever any need for intelligence to evolve in this simulated series of events? Or is all intelligence a marvelously predictable play of meaningful yet ultimately meaningless words?
Have you simulated any answers to those questions, as something has stimulated me to ask not only them?
Roy Niles
logged in via Facebook
Are the laws of physics evolving or evolvable in this simulation. Are the simulations simulatively aware and anticipatory? If yes, then it's more likely to be simulations all the way down.
Geraint Lewis
Professor of Astrophysics at University of Sydney
They can be. One of the things we do is mess around with the laws of physics to see how things influence the evolution of the universe. This is one of the big things in the "is the universe fine tuned for life?" debate.
Ron Chinchen
Retired (ex Probation and Parole Officer)
Is there in truth no reality but merely an infinite number of simulations creating simulations within simulations. Reminds me of the film Thirteenth Floor or are we all merely the dreaming imaginings of some superbeing such as Shiva. Then again this reality may be merely a reflection of the real Dreamtime reality of Australian Indigenous people. In the end does it matter? Surely if I simulate I exist.
Anthony Nolan
Ruminant
Who needs a computer simulated universe when we all reside within a hegemon? Try Gramsci for real understanding.
Geoffrey Edwards
logged in via email @gmail.com
"Not being a philosopher, I will ignore the (seemingly endless) debates about free will and consciousness, but if you take a purely mechanical view of the human brain, the synthetic brain will be as “alive” as the organic brain that made it."
So, you take out the bits that are hard to come to grips with, indeed the only bit that which actually experience. The defining aspect is our conscious experience, whether that is experience of the "real world" or some "simulation." (I assume the simulation…
Read moreGeraint Lewis
Professor of Astrophysics at University of Sydney
I am not ignoring consciousness. There are those who do have a purely mechanical view of the brain, and that with enough neurons and connections will result in a "conscious" being. If there is additional "magic" on top of that, it should obey the laws of the universe, and hence should be simulatable.
Yuri Pannikin
Director
"There are those who do have a purely mechanical view of the brain, and that with enough neurons and connections will result in a "conscious" being."
Not necessarily animal consciousness though. As discussed in another article on artificial intelligence, the 'wet' brain is more than that. Chemical neurotransmitters and hormones are what give the brain and consciousness context in the human/animal experience -- 'qualia' if you like that term.
Computational power is only one aspect, but I guess an all-powerful simulator could add the "magic" to make it work. At a more mundane level though, simulating dopamine, serotonin, epinephrine, testosterone etc in code to enable a mechanical brain sounds like a Sisyphusian task!
Yuri Pannikin
Director
And of course Martin Rees and many of the other Edge crowd would agree with you.
Anne Powles
Retired Psychologist
And in this modern day and age the philosophy starts early. My four year old grandson asked his mother "is this universe real?"
He followed it up with "I sometimes think I just live in a grown up man's dream".
As ever is this the stuff of genius philosophy or the edge of madness?
Michael Marston
logged in via LinkedIn
or just maybe we are part of an advertising simulation model?
http://www.enotes.com/counterfeit-world-salem/counterfeit-world.
Nice read btw.
Kim Peart
Researcher & Writer
This article is an interesting and playful journey.
The best simulations of the future may be built from a stellar web of connected computers, if instant communication between stars is possible with quantum entanglement, or some similar means.
Imagine a stellar web that may draw on the energy of whole galaxies.
Drawing on the energy of each star, a growing stellar web would become a powerful computing tool.
It is in this future, that a virtual world might happen, filled with virtual beings…
Read moreKenneth Mazzarol
Kenneth Mazzarol is a Friend of The Conversation.
Retired
I have always been of the belief that we are in a gigantic vacuum cleaner bag and are merely a piece of dust among an infinite numbers of others. What the hell we are doing here I do have a clue.
Bruce Tabor
Research Scientist at CSIRO
Stop it please! You're undermining my faith in the Flying Spaghetti Monster.
http://en.wikipedia.org/wiki/Flying_Spaghetti_Monster
Dianna Arthur
Dianna Arthur is a Friend of The Conversation.
Environmentalist
Imagine....
Long have we imagined from the first time we applied a charcoal stick to rough cave walls, we have imagined.
Without imagination, we cannot create, invent, without invention we surely are doomed.
Wonderful article.
Dale Bloom
Analyst
If the author is right in his musings we have no way of knowing and we ought to continue living as if we were free agents. If the author is wrong in his musings we have no way of knowing and we ought to act as if we were free agents. So the point is?
Firozali A.Mulla
PhD
You are telling me now> Daily we are in the virtual world and do not seem to get out it . The kids get frenzy with the new games and they love this more then the history I thank you Firozali A.Mulla DBA
Joseph Bernard
Director
"Time you enjoy wasting, was not wasted." John Lennon
Thank you, enjoyed the article as it explores some interesting possibilities.
I think that it is fair to say that in a universe of infinite possibilities, that everything we see is a manifestation of the very fabric of the universe.. ie nothing can exist here and nowhere else, surely .. Computers and software are no different in many ways, as they are an expression of human thinking and just are an extension of our minds.
So the "old chicken and the egg", what came first? Humans or the program?
Thank "god" for the good ole wine subroutine which will fuel the infinite discussions to come..
NB.. Derren Brown is great, he demonstrates how the mind's software can be hacked into :) www.youtube.com/watch?v=befugtgikMg
Comment removed by moderator.
Leo Kerr
Consultant
"Zhuangzi - Now I do not know whether I was then a man dreaming I was a butterfly, or whether I am now a butterfly, dreaming I am a man"
As a simulated entity from a virtual reality let me say that the simulations in this reality will only just reach the singularity goal for which they have been created before dissolving in their self inflicted nightmare. Must have been a bug in the love program module.
Yuri Pannikin
Director
"Zhuangzi - Now I do not know whether I was then a man dreaming I was a butterfly, or whether I am now a butterfly, dreaming I am a man"
Pardon the joke but, a duck consulting a psychiatrist:
Psych: What's your problem.
Duck: I keep thinking I'm a duck.
Psych: But you are a duck!
Only the clever analysts get to advise the duck appropriately and win a subscription to Nihilism Reviews.
Yuri Pannikin
Director
Okay, here is what the psych eventually finds out about the duck.
1. The duck perceives he has problem, otherwise he would not attend the psychiatrist.
2. It's clear that he is a duck, so his problem stems from some alternate perception of himself.
3. Finally, this duck thinks he is a human who thinks he is a duck. Thus the problem.
Talk about the Matrix!
Roger Powell
logged in via Facebook
I see this article as speculation - fascinating to read but improbable. As an atheist, I have already thrown out all the creator theories promoted by religions but this brings her right back again. If there were to be a creator, then maybe a giant computer simulation would be an improvement on all the other theories.
Despite the fact that the author simulates universes as a matter of course, I still find it somewhat implausible and we would still need to ask who created the cosmic programmer. It's easier to save a step.
However, all possibilities should be considered and my question to Geraint is "What scientific experiment can you conceive that might verify or disprove the proposition?"
Geraint Lewis
Professor of Astrophysics at University of Sydney
I agree it is speculation, and as I hoped to point out, looking for "flaws" in our universe are hard, as we are likely to view them as some aspect of interesting physics (e.g. quantized space-time vs computational resolution).
Still fun to think about though :)
George Michaelson
Person
Hello..this is the 1960's calling: we'd like our MEME back. Or at least, you could point out this is a FORTY-PLUS YEAR OLD STORY
http://books.google.com/ngrams/graph?content=simulated+universe&year_start=1800&year_end=2012&corpus=15&smoothing=3&share=
Brian Griffiths
Adj.Professor at Curtin University
'Fed with the stimulus from a synthetic body interacting with a synthetic universe it will experience pain and fear happiness and love even boredom and drowsiness' This assertion fails to acknowledge the 'hard' question of the relationship between brain activity and consciousness. No matter how detailed a neurological analysis of what takes place when I look at a red spot, the experience of 'red' is not addressed. The language that we use to talk about the neurophysiology of the nervous system and its goings-on, is not the language we use to talk about experience. Whatever goes on in the brain and nervous system when I bang my thumb with a hammer it is not 'pain'. 'Pain' is an experience. The relationship between trauma and pain is not perfect. A sportsman injured in a game may be too distracted by what is going on to experience pain.
This is a serious issues (even though I have put in badly) and ought not be glossed over.
Doug Rankin
Plasterer
After wasting much time playing computer games I realised detail is not there until you look - saves ram/cpu. Sounds really familar really (? :) ). But who the hell really cares it's getting unplugged in 17 days anyhow.
Enough intelligence (?) for the day I think.
Rick Ryals
logged in via Facebook
One might think that physicists would look for more traditional solutions to the problem of initial conditions even if the observation includes an apparent preference for carbon based life, like an energy conservation law that simply requires life as a necessary function of the thermodynamic process, for example only, but the point is that there are "first principles" vs a bunch of different types of quantum hand waving..
Carter was right, scientists are ideologically pre-dispositioned to avoid first principles that include a preference to life.
Kim Peart
Researcher & Writer
Rick Ryals ~
As you describe, "scientists are ideologically pre-dispositioned to avoid first principles that include a preference to life."
I have a major problem with this perspective, as I see that it presents a threat to our survival.
This is because I have come to see an absolute necessity to develop a confident survival presence beyond Earth, simply to assure our survival on Earth, whether from the prospect of an asteroid strike, or now the ravages of climate change and ocean acidification…
Read moreRick Ryals
logged in via Facebook
OR... maybe we're just technologically wired to continuously increase the efficiency by which we increase the entropy of the universe. Maybe our instinct to reach for the stars that our observational capabilities provide is just a means of getting us to develop technologies that enable us to "get the most bang for our buck", i.e., maximizing the amount of work that we can do with the available energy. You know, like a flat expanding universe does that a wide open expanding universe can't do since…
Read moreYoron Hamber
Thinking
Interesting :)
But no, any universe that needs to exist needs also to explain what free will means. Because we do have choices and on a personal plane some of us will make choices that are highly improbable. Although statistics show us trends that are logical we still have those unpredictable choices to contend with, and those may also be the ones that moves humanity forward as a whole, creating new trends.
You have HUP to consider to. The Heisenberg uncertainty principle that disallow all…
Read moreKim Peart
Researcher & Writer
Yoron Hamber ~
Going deeper down the rabbit hole, there is the birth of the cosmos as a singularity that then stretches to infinity.
Though stretched, the cosmos still has a primary foundation of oneness, in which the space-time continuum plays out.
As space and time are one and we are in space and time, there is a foundation to our being here that is one with the cosmos.
But, being a singularity stretched, what matters more is the environment in which the singular cosmos happens, as…
Read moreDianna Arthur
Dianna Arthur is a Friend of The Conversation.
Environmentalist
@ Kim Peart
Love your definition. It resonated with me. However, I fear that too many people are in denial of the consequences of their and humanity's actions. Are we in a race against time before enough of us take responsibility and care for our planet?
We cannot even agree to start.
Kim Peart
Researcher & Writer
Dianna Art ~
When ten people move as one, they can change the world and ten can only begin with one, plus one.
I look toward a business plan for a safe Earth, which includes a stellar economy without poverty.
For anyone interested, we could meet in the virtual world to pursue the conversation.
This could be a regular forum with chosen themes aimed at increasing insights.
Kim Peart
http://www.islandearth.com.au/
Zlatko David Beretovac
Sessional University Tutor
This argument has been casually denounced as solipsistic, so I'll just give it a brief defence.
The non-solipsistic version of the simulation argument is that, given that you are living in a society with simulation technology, and that any such society would tend to get better at simulation, the simulated universes would outnumber the primary universe. Thus, you probably living in a simulated universe.
Or, in more technical language with a slightly different emphasis:
at least one of the…
Read moreRoy Niles
logged in via Facebook
If the simulation we live in has no simulator, then it's a simulation of "reality" that is done within our predicting and anticipatory computative living systems and the universe is in effect the simulator, which a computer that relies on human input does not have a chance in hell of accurately simulating.
And if the simulation that is envisioned here has (as it would need to have) a universal simulator, we're just playing with words; and as I said earlier, it's simulators all the way down
Arthur James Egleton Robey
Industrial Electrician
I am a great fan of Lord Reece. Last night I watched a you tube video where he explored similar topic.
Read moreThe fine tuning of Dark Energy has to be so accurate as to be impossible for it to be so by random chance.
The multi-verse has to be invoked to skirt the obvious conclusion that it is by design. Which is anathema to scientists, apparently.
But this explanation is unsatisfactory. Atheists are chasing rainbows. The Ultimate Cause of Reality recedes like an illusion.
Let us assume a Multi-verse…
john tons
post graduate student
I wonder have you let Schrödinger's cat out of the box?
Yoron Hamber
Thinking
heh :)
Wouldn't that be nice, let the Schrödinger's cats roam free. Doesn't it has a brother too, I think?
Alice in wonderland :)
Yoron Hamber
Thinking
One simple point against us being in a 'simulated universe' is the incredible complexity and linear logic we see. A simulated universe needs none of those, magic can rule it as easy as linear logic.
Kim Peart
Researcher & Writer
This question has sprung up in Space Daily ~
http://www.spacedaily.com/reports/Do_we_live_in_a_computer_simulation_UW_researchers_say_idea_can_be_tested_999.html
Edwin Flynn
I am a early retired executive at Worked in Local Government, Education and Financial Services Industries
Have you never sat in your car on the freeway and think about the other people sitting in their cars on the same freeway and the millions of other people sitting in their cars, each with their own thoughts, joys, sadness, happiness, families, plans for the days etc etc. Each one going about their business. Really like looking down on a drop of blood or water through a microscope. Those little microbes and cells going about their business sometimes touching one another.
There was a time no so long ago, when we thought the sun and the planets circled around the earth.
Are we part of something, much like the cells that we see wriggling about in the drop of water under the microscope.
You can go mad thinking about this sort of thing.
Colin Hales
Researcher
The mechanical view of the brain has a fatal flaw: the article claimed ...
"Fed with the stimulus from a synthetic body interacting with a synthetic universe, it will experience pain and fear, happiness and love, even boredom and drowsiness."
This Ignores 20 years of the neuroscience of consciousness and completely fails to account for how the simulated brain can do science ( = scientifically observe. = experience a scientific measurement).
The claim that the simulation will 'experience…
Read moreFirozali A.Mulla
PhD
I am sorry I never believe in UFOs and the mystic signs or the stars and do not believe in the other concept of living in other world except the IT that has changed all I thank you Firozali A.Mulla DBA