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2022-09-21: Science of the James Webb Telescope Explained!

  • 11:58: ... by a family run aerospace machine shop that’s built parts the Mars Rover and the International Space ...

2022-08-17: What If Dark Energy is a New Quantum Field?

  • 13:04: ... way that time travel does. So, if the big rip is possible, so are time machines, and we escape the end of the universe every time it comes ...

2022-06-30: Could We Decode Alien Physics?

  • 15:41: ... occurs to Greg N that we’ll most likely  encounter the machines built by intelligent   civilizations than the lifeforms ...

2022-02-10: The Nature of Space and Time AMA

  • 00:03: ... tried to do this this is the guy who um was just about to build the machine that would have detected the cosmic microwave background radiation ...

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... built by mere humans and so currently i'm working on building machine learning algorithms to try to understand the complex variations in ...

2021-10-20: Will Constructor Theory REWRITE Physics?

  • 06:06: David Deustch gives the example of the perpetual motion machine of the first kind - a device from which infinite energy can be extracted.
  • 06:36: We’d need a separate mechanistic approach to rule out every different type of the perpetual motion machine.

2021-09-07: First Detection of Light from Behind a Black Hole

  • 01:38: ... stitched the image together using the very latest machine learning techniques to achieve an image resolution equivalent to a ...

2021-05-19: Breaking The Heisenberg Uncertainty Principle

  • 00:20: Engineers have gifted physicists with some pretty incredible machines for measuring the universe.

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... was pretty impressive when we built this giant machine that spotted gravitational waves from colliding black holes well we've ...

2020-11-18: The Arrow of Time and How to Reverse It

  • 11:16: ... points us to Scott Aaronson’s essay "The Ghost in the Quantum Turing Machine”, which I’m going to go and read ...

2020-11-11: Can Free Will be Saved in a Deterministic Universe?

  • 04:02: The brain is like a machine for processing information into choices.
  • 04:07: ... can parcel that decision-making machine off from the rest of the universe, and we can ask, what has to happen ...
  • 11:12: So this nexus of quantum information processing may truly be an unpredictable black box decision-making machine, at least some of the time.
  • 11:21: Add to that the fact that its emergent phenomenon, conscious free will, can recursively influence the machine itself.

2020-10-05: Venus May Have Life!

  • 15:02: I go for every second Moore’s law doubling, which leaves my machines basically paralyzed about half the time.

2020-09-21: Could Life Evolve Inside Stars?

  • 04:55: Fair enough - our DNA encodes all the instructions our cells need to build the molecular machinery of life.

2020-08-24: Can Future Colliders Break the Standard Model?

  • 01:16: Physicists have been building machines to accelerate and subsequently obliterate particles since the 1920s.
  • 13:17: Of coordinating thousands of scientists over many decades to build these crazy machines that can crack open the inner workings of spacetime.

2020-08-10: Theory of Everything Controversies: Livestream

  • 00:00: ... variants on on that idea that you need to have an unrealistically big machine to ever test quantum gravity may that be this big collider or you have ...

2020-07-28: What is a Theory of Everything: Livestream

  • 00:00: ... experimental particle physics is that we have this fantastic machine the largest experiment ever ever built a 27-kilometer circular tunnel ...

2020-06-30: Dissolving an Event Horizon

  • 03:04: The time machine is on the other side of that ring, by the way.

2020-06-15: What Happens After the Universe Ends?

  • 15:54: ... that evolved on earth uses the same code for instructing the molecular machinery to translate the ...

2020-06-08: Can Viruses Travel Between Planets?

  • 02:25: ... own energy, and they can’t reproduce without coopting the reproduction machinery of a cell - hence the dispute over whether they can be called ...

2020-05-27: Does Gravity Require Extra Dimensions?

  • 13:29: ... event horizon of a rotating black hole - regions like the Carter time machine and the infinite string of parallel ...
  • 15:44: ... impossible-seeming things like an infinite string of universes or a time machine indicate that the math may have led our physical understanding astray, ...

2020-05-18: Mapping the Multiverse

  • 02:04: Think of the worst spinny amusement park rides, or an astronaut high-g training machine - you'd feel yourself flung outwards by centrifugal force.
  • 08:24: This is the Carter time machine, after the aussie physicist Brandon Carter who did much of the early exploration of the Kerr spacetime.
  • 12:42: ... thing collapses, shutting off any potential magical portals to time machines or new universes - probably before they ever ...

2020-03-24: How Black Holes Spin Space Time

  • 03:27: ... for another episode. For a preview check out our episode on time machines. Yup, the math says you can visit your past within a Kerr black hole. For ...

2020-03-16: How Do Quantum States Manifest In The Classical World?

  • 16:29: ... of the Many worlds interpretation could indeed be a big-bang machine. On the other hand, if the evolution of that wavefunction can't ...

2020-02-03: Are there Infinite Versions of You?

  • 11:34: In fact mostly these ones hit the letter S and pooped on the machine.

2020-01-20: Solving the Three Body Problem

  • 00:20: ... that transformed our erratic-seeming cosmos into a perfectly tuned machine of clockwork predictability. Given the current positions and velocities ...

2019-10-21: Is Time Travel Impossible?

  • 04:53: But for now, to build a useful time machine a wormhole has to be large enough to fit through and it has to be stable.
  • 05:11: In order to keep our wormhole time machine operational, its throat needs to be kept open.
  • 06:51: We can’t completely rule out wormhole or warp drive time machines based just on the energy conditions.
  • 06:58: And as it turns out, there may be other ways to build time machines without either negative or imaginary masses.
  • 08:29: So to build this time machine we just need construct an entire universe – which allows us to travel back in time only within that universe.
  • 09:08: Unless it’s an Interstellar-style black hole . . . general relativity doesn’t directly refute black hole time machine libraries.
  • 09:16: So it seems we have lots of ways to send things back in time, but it all seem useless for actually making time machines for one reason or another.

2019-08-12: Exploring Arecibo in VR 180

  • 00:13: ... built cities and spaceships? and this thing, it's the tip of an enormous machine built to map the universe beyond and to search for other technological ...

2019-07-15: The Quantum Internet

  • 15:03: Battlemechs, submarines, spaceships, DeLorean time machines - nuclear is probably the easiest option for the badass vehicles of the future.

2019-06-20: The Quasar from The Beginning of Time

  • 05:05: When the light analyzed by this machine left its quasar, it was ultraviolet.

2019-04-10: The Holographic Universe Explained

  • 03:27: ... describe the locations of all particles in its volume, but also the full machinery of the volume can exist on its surface – all degrees of freedom needed ...

2019-03-13: Will You Travel to Space?

  • 13:14: ... last week we explored the bad science of perpetual motion machines and announced the winners of the perpetual motion challenge. Check them ...
  • 13:27: ... points out that atoms are perpetual motion machines, and there are hydrogen atoms that have been ticking for the entire age ...
  • 13:36: Well, I guess you could call the atom the best possible perpetual motion machine of the Third Kind.
  • 14:58: ... us for putting the ElectroBOOM video that debunks perpetual motion machines alongside all of the other videos that actually claim to have built ...

2019-03-06: The Impossibility of Perpetual Motion Machines

  • 00:06: But there’s one bit of nonsense that is perhaps more persistent than all others: the perpetual motion machine.
  • 00:19: No working perpetual motion machine has ever been experiment verified.
  • 00:30: We have perpetual motion machines of the first kind - they violate energy conservation - they pump more energy out than they need to keep running.
  • 00:43: ... there are machines of the second kind - they’re a bit more subtle in their wrongness ...
  • 01:18: Designing a perpetual motion machine has a very long history and became quite the craze from the middle ages through the renaissance.
  • 01:23: The first well-documented design for a perpetual motion machine was from the 12th century.
  • 02:05: None of these machines actually worked.
  • 02:48: Thus the proliferation of first-type machines that could generate more energy than they used.
  • 03:20: All machines work by riding this flow of energy as it redistributes itself.
  • 03:26: Machines of the second kind claim to be able to tap reservoirs of energy that are already evenly spread – effectively reversing the growth of entropy.
  • 03:37: Before we get to modern perpetual motion machines, let’s take a look at some actually interesting ideas that illustrate the limit of the second law.
  • 05:30: ... and then pump it back in again, making it a candidate perpetual motion machine. ...
  • 06:06: These are perpetual motion machines that do not attempt to generate energy – they just keep themselves running forever.
  • 06:21: So remove all outside forces – remove all friction, all energy losses of any kind, and surely any machine can tick on forever.
  • 07:25: The best-case scenario for a perpetual motion machine of the third kind is a very, very slow wind-down to stillness.
  • 07:34: Now that we've reviewed three types of possible wrongness in perpetual motion machines, let's look at some of the modern proposals.
  • 09:54: ... question, in which I asked YOU to come up with a perpetual motion machine based on the funky notion of negative ...
  • 11:13: ... the prize for most outlandish goes to Epsilon Centauri, whose machine requires an entire bubble universe with closed, pac-man borders, ...
  • 11:55: And I leave you with wise words from someone who designed quite a few perpetual motion machines himself.
  • 12:21: Had only da Vinci known that his own perpetual motion machines could’ve score him such cool swag from Space Time.

2019-02-07: Sound Waves from the Beginning of Time

  • 16:37: So, no perpetual motion machines.

2019-01-30: Perpetual Motion From Negative Mass?

  • 00:13: Because you could use negative-mass apples to build warp drives, travel in time, and construct a perpetual motion machine.
  • 13:18: ... positive and negative mass objects to build a perpetual motion machine. ...
  • 13:37: And for extra credit, based on your design, what’s the maximum power can you get out of your machine?
  • 14:21: Winning perpetual motion machines will be revealed in an upcoming episode of space time.

2019-01-24: The Crisis in Cosmology

  • 14:51: that they produce perpetual motion machines and paradoxes left and right.

2018-12-06: Did Life on Earth Come from Space?

  • 00:37: ... destroy any unprotected microbe in a fraction a second DNA molecular machinery and cell walls are shredded by ultraviolet light tardigrades and ...

2018-10-31: Are Virtual Particles A New Layer of Reality?

  • 02:01: So quantum field theory is the machinery behind the standard model of particle physics.
  • 13:32: That said, for something that doesn't exist, they're surprisingly useful for describing the weird underlying machinery in our quantum space-time.

2018-10-18: What are the Strings in String Theory?

  • 00:39: We expect the most fundamental machinery to have the fewest possible moving parts, or free parameters.

2018-09-20: Quantum Gravity and the Hardest Problem in Physics

  • 09:03: If not, you could build perpetual motion machines, for example, using the Casimir effect.

2018-05-23: Why Quantum Information is Never Destroyed

  • 11:29: In a related question, AFastidiousCuber asks why free energy and perpetual motion machines are impossible?

2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!)

  • 02:12: The molecular machinery of even a single cell defies belief.
  • 02:35: ... molecular machinery made of RNA and protein unpacks, transcribes, cuts and splices, and ...
  • 07:57: Living things are incredible heat dissipation entropy-maximizing machines.

2017-11-22: Suicide Space Robots

  • 09:37: It's our way of honoring the many brilliant scientists and engineers who poured their own lives into these ingenious machines.
  • 09:46: And eventually real live human explorers will follow these brave machines-- hopefully, with far fewer fatalities.

2017-11-08: Zero-Point Energy Demystified

  • 03:51: This is why so-called zero-point energy machines are baloney.

2017-11-02: The Vacuum Catastrophe

  • 04:31: ... be able to knowledgeably scoff at zero point energy perpetual motion machines. ...

2017-10-19: The Nature of Nothing

  • 04:20: ... call these virtual particles, and they seem to be the machinery under the hood of all particle interactions in the universe, at least as ...

2017-03-08: The Race to a Habitable Exoplanet - Time Warp Challenge

  • 03:40: When you transform the diagram to the perspective of the Annihilator, the paradox should suddenly appear to act like a time machine.

2017-02-15: Telescopes of Tomorrow

  • 10:27: It includes a great lecture on telescopes, taking you from their most basic workings to the big bad machines we use in modern astronomy.

2016-12-21: Have They Seen Us?

  • 08:18: Such a machine also just happens to be perfect for spotting alien television bubbles.

2016-10-26: The Many Worlds of the Quantum Multiverse

  • 02:40: A machine containing a radioactive element is set to shatter the flask in the event that the radioactive element decays.

2016-09-21: Quantum Entanglement and the Great Bohr-Einstein Debate

  • 12:48: Strofi Kornego and others wonder if life might be the ultimate Von Neumann machine.
  • 13:11: Again, if one Von Neumann machine entering our system is likely, then lots are likely.

2016-09-14: Self-Replicating Robots and Galactic Domination

  • 00:13: But what about almost-living machines?
  • 02:40: We touched on the idea of self-replicating machines recently when we talked about the Dyson Swarm.
  • 02:51: Imagine-- a single machine that can build a huge variety of other machines, including itself.
  • 03:20: He called it a "universal assembler." These days, we call it a Von Neumann Machine.
  • 03:41: Freeman Dyson imagined several types of Von Neumann machine, including a Martian terraformer and the Astro-chicken.
  • 04:22: We can imagine a Von Neumann Machine much smaller than the infrastructure it is able to build.
  • 04:29: This suddenly makes it reasonable to use such machines for some pretty cosmic scale endeavors.
  • 04:40: ... space operation-- might be best handled with self-replicating machines. ...
  • 05:18: The vessel contains a universal assembler and minimal mining and/or processing machinery.
  • 10:16: ... future of robotics, including space robots and evolving self-assembling machines, from Professor John Long's Robotics ...

2016-02-24: Why the Big Bang Definitely Happened

  • 02:56: While general relativity is incredibly successful, it doesn't contain the machinery to describe the quantum scale gravity of that first speck.

2016-01-27: The Origin of Matter and Time

  • 06:56: In those particles, and in the configuration of the ensemble-- the object itself-- the internal machinery of the thing evolves.
  • 07:59: That time manifests as the rate of change of its internal machinery.
  • 08:04: And the rate is governed by the speed at which that machinery can interact.

2015-10-28: Is The Alcubierre Warp Drive Possible?

  • 03:59: Any FTL device can, in principle, be used to make a time machine.
  • 04:30: Does anyone else get the idea that Stephen Hawking really doesn't want us to build time machines?

2015-08-05: What Physics Teachers Get Wrong About Tides!

  • 11:41: ... classical field theory versions of something and then add to them the machinery of quantum mechanics to sort of get a quantized version of the ...

2015-05-20: The Real Meaning of E=mc²

  • 09:25: ... microwave ovens, Tang, Velcro, cordless power tools, the space pen, MRI machines-- none of those are NASA ...
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