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Can the universe be a simulation? / SurprizingFacts

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A four-qubit computer from IBM, the foremost word in computing, can as a result pave the way for computers powerful enough to simulate the universe

Every day we accept, as a matter of course, that what we perceive as reality is in fact a reflection of objective reality. The fact that the atoms and molecules that make up our bodies exist in reality; That photons interacting with us have energy and momentum; That neutrinos passing through our body are indeed quantum particles. But, perhaps, the universe, from the smallest subatomic particles to the largest collections of galaxies, does not exist physically, but is just a simulation working in another, real reality. Two of my readers (and an old school friend) want to know more about this idea with simulation.

Rudy: I'm skeptical about this idea, but it's quite interesting.
Samir: This is a very interesting topic and I would really like to hear what Ethan will say.

This may sound like a science fiction story, but it is supported by certain physical considerations.

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Photons with completely different energy levels move at the same speed. This and other features can serve as proof that our universe is just a simulation

One of the greatest mysteries of nature is why such laws exist in the laws of physics. Why is there a limited set of fundamental particles, interactions, and constants that describe the universe? We did not find any mathematical or physical principles determining what our universe should consist of, or allowing us to derive some fundamental things. We ourselves are inside the universe and can observe only a limited part of it with a limited level of sensitivity. Partially this is due to the limitations inherent in our equipment, but in part these limitations are fundamental.


The Observed Universe on a logarithmic scale, where the edge of red light indicates the relic radiation we see.

We do not see anything beyond 46 billion light years, since the amount of time that has passed since the Big Bang, together with the speed of light, is not enough to look further. Today we can not study distances less than 10 -19 because of the limitations of our accelerators, but the Universe itself has a fundamental quantum limitation in 10 -35 . Even with unlimited technologies, we could not Would probe smaller distances. And attempts to simultaneously measure several parameters open fundamental uncertainties, which in principle can not be overcome: the quantum limitations of the cognizable. 19459006 19459005 19459013 19459002 19459003 Illustration of the fundamental uncertainty between location and momentum at the quantum level

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It is possible that there are real, physical explanations of why these and other parameters of the universe have exactly this kind, and we just have not yet discovered these explanations. But we can also assume that their values ​​are such because they were programmed into our universe. Not in a figurative sense, but in the real sense: it is possible that the universe really is a simulation. Our computing power continues to increase at an alarming rate for the last 70 years. We switched from calculators with four functions comparable in size to the building, and worked slower than mathematicians to supercomputers the size of a printer capable of performing simulations with trillions of particles and simulating billions of years in minutes.

If the computing power increases to fairly large levels, we can, in principle, simulate every particle of the universe during the entire period of our history. If the computer on which the situation is going on would be quantum, capable of holding each particle in an undefined quantum state, it could build this quantum uncertainty into all aspects of the simulation. If in this simulation there were planets with living, intelligent organisms, would they be able to determine that they live in a simulation? And of course, it's quite easy to find scientists who claim that they can not. For example, Rich Teril, a scientist from NASA, makes statements like:

Even what we imagine to be continuous – time, energy, space, volume – has finite limitations for its meanings. Then our universe is both finite and computable. These properties allow the universe to be a simulation.


Certain correlations of physical observations may be signs of a simulation of the universe, but many assumptions remain uncertain.

But from a physical point of view this Maybe not so. Quantum uncertainty can be real, but this does not mean that space and time are quantized, or that the photon energy can not be arbitrarily small. The observed Universe can be finite, but if one adds to it the unobservable, it can turn out to be infinite. We also use various tricks to reduce the computational load in simulations, but the evidence that the universe uses the same tricks should be seen as "blurry" results at sufficient short distances, which we do not observe.


One of the channels of the GEO600 detectors, looking for blurring of signals corresponding to the fact that the universe is a simulation.

Although the results of information theory are often manifested in advanced research on theoretical physics, this may be the result of the fact that both disciplines obey internally consistent mathematical relations. Some of the arguments are that in the future it will be easy to simulate the mind, which means that simulated minds at some point will be more than organic, and therefore most likely the fact that we all live in a simulation are so superficial and so easy Refute that it becomes sad because they are used, as reasonable. For example, why would anyone, capable of simulating the entire universe, take care of the simulation of the human mind? In April 2016, a debate was held on this subject involving several scientists, and Lisa Randall spoke best of all on the hypothesis of the simulation:

I really wonder why so many people consider this issue interesting.

This opportunity, of course, bores the imagination. And we, of course, can impose restrictions on this hypothesis, measuring with ever better accuracy and at ever higher energies space, time, matter and energy. But our understanding of reality has always progressed because we asked deeper questions about the universe in new and fundamental ways. The appeal to the anthropic principle, as well as the appeal to the simulation hypothesis in search of answers to today's difficult questions, looks like a disappointment in science.


NASA Chandra X-ray telescope could impose limitations on Granularity of space, observing distant quasars

If you find evidence – for example, when studying cosmic rays – that space-time is discrete, this has a favorable effect on our knowledge of the universe, but does not prove the hypothesis of simulation . It is generally impossible to prove – any glitches that we can or can not find can be properties of the Universe itself, or parameters placed or corrected by the masters of the simulation. From the philosophical point of view, such a hypothesis may be attractive to a civilization that believes that it is on the verge of creating an artificial intelligence. It is possible that for a sufficiently advanced simulator we will appear as simple as the pixels in the game Conway's "Life"

But we do not judge the scientific merit or plausibility of the idea of ​​its attractiveness . Physics is so fascinating in particular because of its counterintuity, and also because of how strong it is in terms of predictions. Even if we really live in a simulation, this should not influence our search for ways to understand the laws of nature, their origin, the reasons why the fundamental constants are just such, or answers to other questions that can be asked about the nature of reality. "Because we live in a simulation" is not an answer to these questions; This can simply be an integral part of our reality.

The mysteries of nature remain mysteries that we need to solve, and it is we who must decide to find answers to them.

Ethan Siegel – astrophysicist , Popularizer of science, author of the blog Starts With A Bang! He wrote books "Beyond the Galaxy" [Beyond The Galaxy]and "Treknologia: The Science of the Star Trek" [Treknology].