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	2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table? 11:31: When we combine our experimental data with our simulations we can make graphs like this one. 13:23: And our computer simulations agree. 11:31: When we combine our experimental data with our simulations we can make graphs like this one. 13:23: And our computer simulations agree.
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 13:34: ... researchers then use the model to run a simulation of the emergence of intelligent civilizations over time, in which some ... 13:50: The simulation tells us all sorts of weird and surprising things about how space is populated.
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 04:36: ... lens images pretty messy. For   example, here are some simulations of distant galaxies that have been lensed by a second ...
	2022-08-03: What Happens Inside a Proton? 02:06: ... that people are exceptionally  clever, and came up with lattice simulations. ... 12:52: ... But they depend on it a very simple way.   You can run your simulation multiple times for different lattice spacings to figure ... 13:36: ... the exotic properties of quark-gluon plasma.   These simulations were also an essential part of the prediction side of the new muon ... 14:32: ... power grows, one day we’ll   likely be able to build detailed simulations of entire collections of hadrons like the nucleus   of a ... 12:52: ... But they depend on it a very simple way.   You can run your simulation multiple times for different lattice spacings to figure out   that ... 02:06: ... that people are exceptionally  clever, and came up with lattice simulations. ... 13:36: ... the exotic properties of quark-gluon plasma.   These simulations were also an essential part of the prediction side of the new muon ... 14:32: ... power grows, one day we’ll   likely be able to build detailed simulations of entire collections of hadrons like the nucleus   of a ...
	2022-06-01: What If Physics IS NOT Describing Reality? 13:13: ... the universe almost certainly is not a simulation. But you can’t be too careful. If you agree and   would like to ...
	2022-04-20: Does the Universe Create Itself? 17:39: ... still isn’t that we’re in a black hole. And it’s not aliens or a simulation either. ...
	2022-01-27: How Does Gravity Escape A Black Hole? 12:29: ... friends at Center for Computational Astrophysics to run a few Universe simulations and track the evolution of the entity known as Alex ... 12:41: In one of those simulations you live 3000 years and become emperor of space, and in another you star in Interstellar instead of Matthew McConaughey. 12:50: But in all of the simulations you are incredibly generous, interesting, and much loved by all the other simulated entities. 12:59: Thank you for your support in this simulation. 13:06: ... theory, and then went from the tiny to the enormous, exploring how we do simulations of everything from the sizes of planets to the size of the ... 14:47: And speaking of corrections, for our episode on astrophysical simulations, Mercurius314 spotted a serious blunder. 15:39: ... by the simulations we showed of the inevitable collision of the Milky Way with the Andomeda ... 16:57: ... a perfect universe; wouldn't that be ultimate proof that we are in a simulation? ... 17:47: OR the simulations might run in a loop and the top layer is simulated by the bottom. 12:29: ... friends at Center for Computational Astrophysics to run a few Universe simulations and track the evolution of the entity known as Alex ... 12:41: In one of those simulations you live 3000 years and become emperor of space, and in another you star in Interstellar instead of Matthew McConaughey. 12:50: But in all of the simulations you are incredibly generous, interesting, and much loved by all the other simulated entities. 13:06: ... theory, and then went from the tiny to the enormous, exploring how we do simulations of everything from the sizes of planets to the size of the ... 14:47: And speaking of corrections, for our episode on astrophysical simulations, Mercurius314 spotted a serious blunder. 15:39: ... by the simulations we showed of the inevitable collision of the Milky Way with the Andomeda ... 17:47: OR the simulations might run in a loop and the top layer is simulated by the bottom. 14:47: And speaking of corrections, for our episode on astrophysical simulations, Mercurius314 spotted a serious blunder.
	2022-01-19: How To Build The Universe in a Computer 00:59: And simulations of galaxy collisions are just the beginning. 01:26: ... astronomer Erik Holmberg  conducted what was probably the first simulation of the universe, right when the first  programmable computers were ... 02:04: ... the simulation went like this: Holmberg started with a pair of these ... 02:37: ... so the two galaxies collided, just as with our modern supercomputer simulations, he witnessed the destruction of the disks, the throwing-off of tidal ... 03:47: And this particular type of numerical  calculation is called an N-body simulation. 03:53: In an N-Body simulation Newton’s laws of motion and gravity are applied over a series of time steps. 04:10: The predictions of these N-body simulations can be as accurate as you like, as long as you make the time steps small enough. 04:37: But if we want realistic simulations of say, a galaxy with its billions of stars, we need to do a bit better. 04:44: ... missions - but actually, it’s improved nowhere near enough to do N-body simulations of entire galaxies using the method that I ... 05:02: In the simplest type of N-body simulation you need to compute the effect of every particle on every other particle. 05:14: For a modern one-million particle simulation of a star cluster, that’s a trillion computations per time step. 05:26: ... example, in a cosmological simulation we’re trying to watch the detailed formation of individual galaxies, as ... 05:45: To do these simulations, astrophysicists have come up with some ingenious tricks. 06:36: Next, you run an N-body simulation by calculating  the summed gravitational pull on each given particle. 08:17: Now we call these hydrodynamic simulations - they simulate the flow of gas using the equations of fluid dynamics. 09:05: ... practice, modern simulations often use an amalgam of these methods - for example SPH for large scale ... 09:17: Astrophysicists often inject all sorts of other physics into their simulations. 09:22: In your galaxy simulation you might need a separate prescription to describes how stars age and die. 09:43: ... on  modern computing clusters, we can produce some pretty insane simulations. ... 11:08: None of these simulations contain the full information of an actual universe - or even a tiny part of it. 11:35: We’ve talked about this simulation hypothesis stuff before, and maybe we’ll come back to it. 11:40: But for now let’s just be proud of the science that we can get from modern simulations. 11:51: ... the fidelity and size of our simulations will only get better as computing power continues its exponential ... 11:35: We’ve talked about this simulation hypothesis stuff before, and maybe we’ll come back to it. 03:53: In an N-Body simulation Newton’s laws of motion and gravity are applied over a series of time steps. 11:13: ... contains unthinkably more information than is contained in a typical simulation,  which just tracks particle  positions and ... 10:23: One of the most famous is  the Millennium simulation   from the Max-Planck institute in Germany. 00:59: And simulations of galaxy collisions are just the beginning. 02:37: ... so the two galaxies collided, just as with our modern supercomputer simulations, he witnessed the destruction of the disks, the throwing-off of tidal ... 04:10: The predictions of these N-body simulations can be as accurate as you like, as long as you make the time steps small enough. 04:37: But if we want realistic simulations of say, a galaxy with its billions of stars, we need to do a bit better. 04:44: ... missions - but actually, it’s improved nowhere near enough to do N-body simulations of entire galaxies using the method that I ... 05:45: To do these simulations, astrophysicists have come up with some ingenious tricks. 08:17: Now we call these hydrodynamic simulations - they simulate the flow of gas using the equations of fluid dynamics. 09:05: ... practice, modern simulations often use an amalgam of these methods - for example SPH for large scale ... 09:17: Astrophysicists often inject all sorts of other physics into their simulations. 09:43: ... on  modern computing clusters, we can produce some pretty insane simulations. ... 11:08: None of these simulations contain the full information of an actual universe - or even a tiny part of it. 11:40: But for now let’s just be proud of the science that we can get from modern simulations. 11:51: ... the fidelity and size of our simulations will only get better as computing power continues its exponential ... 08:17: Now we call these hydrodynamic simulations - they simulate the flow of gas using the equations of fluid dynamics. 05:45: To do these simulations, astrophysicists have come up with some ingenious tricks. 10:14: And then we have cosmological simulations  which create entire virtual universes, from the moment the first  atoms formed to the modern day. 10:39: ... the current largest cosmological simulations  is AbacusSummit, which just last year simulated 70 trillion particles on ...
	2022-01-12: How To Simulate The Universe With DFT 00:00: ... universe to solve the schrodinger equation and do full quantum simulation of some chunk of the universe, how big would that chunk ... 06:18: In fact astrophysicists do huge galaxy simulations of millions of particles without doing millions-of-dimension calculations. 08:26: ... for more than a few particles, researchers still manage to do quantum simulations of some extremely complex ... 09:01: ... an example, here’s a quantum simulation of the millions of atoms comprising the capsid of a virus done using ... 06:18: In fact astrophysicists do huge galaxy simulations of millions of particles without doing millions-of-dimension calculations. 08:26: ... for more than a few particles, researchers still manage to do quantum simulations of some extremely complex ...
	2021-12-20: What Happens If A Black Hole Hits Earth? 17:55: ... this might be the most testable prediction of string theory. There are simulations that suggest that the gravitational waves created when fuzzball merge ...
	2021-12-10: 2021 End of Year AMA! 00:02: ... too closely um but the the first thing to note is that these were simulations okay this experiment hasn't been actually conducted okay so in their ...
	2021-10-20: Will Constructor Theory REWRITE Physics? 15:34: ... example we could be a simulation. TBatlas says   that the universe saves CPU space by not ...
	2020-08-17: How Stars Destroy Each Other 14:07: Here’s a simulation from the SXS - simulating extreme spacetimes group at ... that shows how the event horizons merge.
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 10:28: Based on our calculations and simulations of how stars die, that minimum black hole mass of 5 Suns seems about right.
	2020-04-28: Space Time Livestream: Ask Matt Anything 00:00: ... this to what to learn what universe emerges is to run a full universe simulation and see what universe emerges okay and so you know in the sense of a ...
	2020-01-20: Solving the Three Body Problem 06:09: ... and when applied to the motion of many bodies it’s an N-body simulation. ... 06:20: ... modern computers, N-body simulations can accurately predict the motion of the planets into the distant future ...
	2019-12-09: The Doomsday Argument 10:37: This is the definition invoked in the simulation hypothesis and the Boltzmann brain scenarios. 10:56: For example, you could be one of countless simulations of yourself in some far-future experiment to recreate the past - an ancestor simulation. 10:37: This is the definition invoked in the simulation hypothesis and the Boltzmann brain scenarios. 10:56: For example, you could be one of countless simulations of yourself in some far-future experiment to recreate the past - an ancestor simulation.
	2019-11-11: Does Life Need a Multiverse to Exist? 01:58: ... Or 2) someone fiddled with the dials - be it god or whoever built the simulation. Or 3) we didn’t get lucky and there was no fiddling - it’s just that ...
	2019-10-07: Black Hole Harmonics 06:10: ... advantage of first trying this with a simulation is 1) you don’t have to use a signal degraded by a billion years of ...
	2019-09-03: Is Earth's Magnetic Field Reversing? 10:18: ... simulations show that the dynamo effect should indeed produce a large-scale dipole ... 10:29: For those who don’t trust computer simulations – how about building our own giant spinning ball of molten metal? 10:18: ... simulations show that the dynamo effect should indeed produce a large-scale dipole ... 10:29: For those who don’t trust computer simulations – how about building our own giant spinning ball of molten metal?
	2019-06-17: How Black Holes Kill Galaxies 02:54: ... Energy we expect 'Bottom up Galaxy formation' this is what we see in our simulations of the Universe and also mostly agrees with what we see when we look out ... 05:24: ... of gas flowed into those clusters from the outside Universe In our simulations of the Universe clustered ellipticals end up much bigger and bluer Due ... 02:54: ... Energy we expect 'Bottom up Galaxy formation' this is what we see in our simulations of the Universe and also mostly agrees with what we see when we look out ... 05:24: ... of gas flowed into those clusters from the outside Universe In our simulations of the Universe clustered ellipticals end up much bigger and bluer Due ...
	2019-06-06: The Alchemy of Neutron Star Collisions 02:47: ... in the nebula that our solar system formed from the researchers then did simulations to figure out how long ago and how far away the neutron star merger that ...
	2019-05-01: The Real Science of the EHT Black Hole 08:55: ... team simulated this whole process with a magneto-hydrodynamic simulation that weaves in all of the physics of fluid flow and magnetic fields, in ...
	2019-01-24: The Crisis in Cosmology 14:32: And yeah, those measures tell us that dark matter has positive mass I'd need to do the simulations, but I have a feeling...
	2019-01-09: Are Dark Matter And Dark Energy The Same? 06:15: The author uses these ideas about the interactions of negative and positive mass particles to create an N-body simulation. 06:32: Those simulations showed that galaxies do indeed spin more quickly when surrounded by negative mass particles. 12:41: Those galaxy rotation simulations are fascinating. 06:32: Those simulations showed that galaxies do indeed spin more quickly when surrounded by negative mass particles. 12:41: Those galaxy rotation simulations are fascinating.
	2018-11-21: 'Oumuamua Is Not Aliens 16:10: Some of you took that to be evidence for the simulation hypothesis, but actually it's just that the exponent got lost in the cut and paste.
	2018-10-18: What are the Strings in String Theory? 13:50: ... our universe, and incidentally, what it would take to compute a universe simulation on the event horizon of a black ...
	2018-10-10: Computing a Universe Simulation 00:19: [MUSIC PLAYING] Look, I'm not saying the universe is a simulation. 00:32: ... the original, physical universe, rather than somewhere deep in the simulation nest, we can still think of our universe's underlying mechanics as ... 10:26: ... you can only read out the simulation results in Hawking radiation as those black holes evaporate, which will ... 10:43: ... depending on your assumptions-- by the way, getting your results of the simulation will take forever, nearly ... 11:29: I suppose that has implications for the simulation hypothesis. 00:32: ... the original, physical universe, rather than somewhere deep in the simulation nest, we can still think of our universe's underlying mechanics as ...
	2018-09-12: How Much Information is in the Universe? 00:52: And then there's the simulation hypothesis, in which that computation is engineered by who knows what, or who. 11:19: ... assuming no one switches off the simulation, I'll see you next week for a new episode of "Space Time." So we're a bit ... 00:52: And then there's the simulation hypothesis, in which that computation is engineered by who knows what, or who. 11:19: ... assuming no one switches off the simulation, I'll see you next week for a new episode of "Space Time." So we're a bit ...
	2018-03-28: The Andromeda-Milky Way Collision 05:00: Van der Marel and team also ran a computer simulation to study the consequences of this collision. 05:06: They used simulations of the gravitational interactions of millions of particles representing groups of stars and dark matter. 05:25: This is an animated representation of the predictions of that simulation. 07:22: ... der Marel, et al's, simulation follows several candidate suns, simulation particles with similar orbits ... 05:06: They used simulations of the gravitational interactions of millions of particles representing groups of stars and dark matter.
	2018-01-31: Kronos: Devourer Of Worlds 07:02: Well, computer simulations of planet formation do show that planets can fall into their home stars.
	2018-01-24: The End of the Habitable Zone 10:29: In no time at all you'll be coding gravity simulations in Python and calculating the radiation emitted by black holes.
	2018-01-17: Horizon Radiation 13:26: Now these are from asteroseismology simulations made by Manuel Perez de Lima Lopez.
	2018-01-10: What Do Stars Sound Like? 09:53: In no time at all, you will be coding gravity simulations in Python and calculating the radiation emitted by black holes.
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 04:57: PZ 17 performed computer simulations to find the frequency of such kicks sending objects close to the earth at such high speeds. 05:25: PZ 17 performed more computer simulations to rewind the motion of both Oumuamua and the 3,700 stars within 100 light years of the sun. 04:57: PZ 17 performed computer simulations to find the frequency of such kicks sending objects close to the earth at such high speeds. 05:25: PZ 17 performed more computer simulations to rewind the motion of both Oumuamua and the 3,700 stars within 100 light years of the sun.
	2017-10-25: The Missing Mass Mystery 05:20: Supercomputer simulations reveal the shape of this large-scale structure that should result from this gravitational collapse.
	2017-06-07: Supervoids vs Colliding Universes! 03:18: Simulations show that you should get a spot that size in the CMB in around 1 in 50 universes.
	2017-05-10: The Great American Eclipse 10:00: Last week we talked about a wild idea by philosopher Nick Bostrom that we live in an ancestor simulation. 10:09: A few people brought up the Mandela effect as evidence that we live in a simulation. 11:02: ... you pointed out that Neil deGrasse Tyson has actually argued against the simulation hypothesis elsewhere, whereas he appeared to argue for it in that ... 11:47: Shiva asks what happens when the simulation runs out of funding and is terminated. 11:02: ... you pointed out that Neil deGrasse Tyson has actually argued against the simulation hypothesis elsewhere, whereas he appeared to argue for it in that ... 11:47: Shiva asks what happens when the simulation runs out of funding and is terminated.
	2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson 00:06: ... more lifelike, it's becoming clear that at some point, perhaps soon, our simulations will be indistinguishable from ... 00:21: Could we be in a simulation now? 00:49: ... about the recent articles about the possibility of us being part of a simulation and the Big Bang being just the seeding event of such a ... 01:05: Well, so who made the simulation? 02:03: So the idea that if you need to produce one universe capable of producing universe simulations. 02:09: ... if that universe produces billions of universe simulations, then any universe that you happen to find yourself in-- is more likely ... 03:38: But before we do so, we should be clear about what type of simulation we're talking about here. 04:13: I'm talking about so-called ancestor simulations, an idea proposed by Oxford University's Nick Bostrom. 04:22: ... the sensory input to that brain with enough fidelity to convince the simulation that it's a real ... 04:57: ... science-- he proposes that an advanced civilization may want to run simulations of its own history to study the behavior of the types of minds that ... 05:08: He calls these ancestor simulations. 05:55: A full ancestor simulation would simulate all humans that ever lived, going back, say, 50,000 years. 07:17: ... more orders of magnitude in the computing power needed to run the simulation. ... 07:28: Bostrom claims the following, which he calls the simulation argument. 07:33: ... ancestor simulations are something that even some civilizations end up creating-- so if they ... 07:48: Therefore, we are an ancestor simulation. 08:19: But both ancestor simulations and Boltzmann brains require us to invoke something like the Copernican principle. 09:03: ... if the virtual minds of an ancestor simulation are vastly more common than the minds of the original living creatures ... 09:22: I should note that Bostrom is on record as placing the odds at less than 50% that we're a simulation. 09:28: ... all civilizations die out before being able to make vast scale ancestor simulations, or essentially no super advanced civilizations choose to make ... 09:39: The ancestor simulation idea suffers from some of the same issues as the Boltzmann brain idea. 10:09: ... in the case of ancestor simulations, upon deciding that we are simulated, we acknowledge that there is no ... 10:22: Bostrom himself points out that, upon being found out by one of its resident minds, the simulation can be instantly edited or rewound. 10:34: These simulations can only cover a tiny fraction of the universe. 11:43: But I wonder if he needs to reject his own ancestor simulation idea on the same grounds. 11:48: Highly specific scenarios like ancestor simulations or Boltzmann brains generate impossibly large numbers of minds that are identical to our own. 12:54: As special thanks, we wanted to assure you two, in particular, that you are not simulations. 07:28: Bostrom claims the following, which he calls the simulation argument. 09:39: The ancestor simulation idea suffers from some of the same issues as the Boltzmann brain idea. 11:43: But I wonder if he needs to reject his own ancestor simulation idea on the same grounds. 09:39: The ancestor simulation idea suffers from some of the same issues as the Boltzmann brain idea. 00:06: ... more lifelike, it's becoming clear that at some point, perhaps soon, our simulations will be indistinguishable from ... 02:03: So the idea that if you need to produce one universe capable of producing universe simulations. 02:09: ... if that universe produces billions of universe simulations, then any universe that you happen to find yourself in-- is more likely ... 04:13: I'm talking about so-called ancestor simulations, an idea proposed by Oxford University's Nick Bostrom. 04:57: ... science-- he proposes that an advanced civilization may want to run simulations of its own history to study the behavior of the types of minds that ... 05:08: He calls these ancestor simulations. 07:33: ... ancestor simulations are something that even some civilizations end up creating-- so if they ... 08:19: But both ancestor simulations and Boltzmann brains require us to invoke something like the Copernican principle. 09:28: ... all civilizations die out before being able to make vast scale ancestor simulations, or essentially no super advanced civilizations choose to make ... 10:09: ... in the case of ancestor simulations, upon deciding that we are simulated, we acknowledge that there is no ... 10:34: These simulations can only cover a tiny fraction of the universe. 11:48: Highly specific scenarios like ancestor simulations or Boltzmann brains generate impossibly large numbers of minds that are identical to our own. 12:54: As special thanks, we wanted to assure you two, in particular, that you are not simulations.
	2017-04-26: Are You a Boltzmann Brain? 09:56: And that's the idea that we live in a simulation.
	2017-01-11: The EM Drive: Fact or Fantasy? 08:05: ... two separate papers, Harold White performs computer simulations, which he argues demonstrates that such a medium can reproduce certain ...
	2016-07-20: The Future of Gravitational Waves 03:05: Two, exhaustive computer simulations test how often this signal processing tech gets tricked into falsely reporting a detection.
	2016-07-06: Juno to Reveal Jupiter's Violent Past 04:29: Astrophysicists have run many computer simulations to find formation scenarios that lead to the configuration of planets that we see today. 06:03: Well, computer simulations show that something like this may be expected given the right starting position for Jupiter. 06:15: ... simulations predict that a protoplanetary disk capable of forming Venus and Earth ... 09:45: Answer that, and we can nail down these simulations to truly understand our planet's origin. 04:29: Astrophysicists have run many computer simulations to find formation scenarios that lead to the configuration of planets that we see today. 06:03: Well, computer simulations show that something like this may be expected given the right starting position for Jupiter. 06:15: ... simulations predict that a protoplanetary disk capable of forming Venus and Earth ... 09:45: Answer that, and we can nail down these simulations to truly understand our planet's origin. 06:15: ... simulations predict that a protoplanetary disk capable of forming Venus and Earth should ...
	2016-06-22: Planck's Constant and The Origin of Quantum Mechanics 13:34: ... an enormous range of possible lens mass distributions with computer simulations. ...
	2016-06-15: The Strange Universe of Gravitational Lensing 09:03: But real lensing simulations show us what black holes should look like up close.
	2016-02-24: Why the Big Bang Definitely Happened 01:15: ... observations to particle collider experiments to supercomputer simulations. ...
	2016-02-17: Planet X Discovered?? + Challenge Winners! 01:31: ... it was Brown and Batygin who first ran the exhaustive computer simulations and found a single compelling solution, a very, very distant giant ...
	2015-11-18: 5 Ways to Stop a Killer Asteroid 07:27: ... is, if you believe the supercomputer simulations of HAIV team, a one megaton H-bomb should break up a 500 meter asteroid ...
	2015-03-11: What Will Destroy Planet Earth? 03:00: ... linked in the description, some French physicists ran 2,500 distinct simulations of the solar system's evolution over the next few billion ... 03:17: 99% of the simulation stay faithful to that. 03:26: In one simulation, about four billion years from now, Earth and Mars actually collide with enough energy to do serious structural damage. 04:40: But the best recent simulations show that Earth will end up just inside the sun and fry. 04:45: Now, as always, it's prudent to see whether that answer holds up under future simulations. 03:17: 99% of the simulation stay faithful to that. 03:00: ... linked in the description, some French physicists ran 2,500 distinct simulations of the solar system's evolution over the next few billion ... 04:40: But the best recent simulations show that Earth will end up just inside the sun and fry. 04:45: Now, as always, it's prudent to see whether that answer holds up under future simulations.

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