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2022-11-23: How To See Black Holes By Catching Neutrinos

  • 02:42: It creates 10^38 - a hundred trillion trillion trillion neutrinos every second in the fusion reactions in its core.

2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table?

  • 16:17: It’s mildly radioactive, extremely useful in medical imaging, and is the critical catalyst for low-temperature fusion.

2022-09-14: Could the Higgs Boson Lead Us to Dark Matter?

  • 11:08: ... example, this is the vector boson fusion channel of Higgs production, in which a pair of quarks in the colliding ...

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

  • 16:39: ... diffuse interstellar material as reaction  mass and fusion fuel for the slowdown phase.   Actually Tony Tee   ...

2022-06-22: Is Interstellar Travel Impossible?

  • 03:07: For example, really REALLY big light sails, or compact fusion drives, or matter-antimatter engines.

2022-06-01: What If Physics IS NOT Describing Reality?

  • 15:25: ... star because more hydrogen fuel gets pumped into  the fusion core. It’s believed that the oddly blue   stars at the cores ...

2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life?

  • 03:40: ... hotter   and hotter and eventually ignited in nuclear  fusion. The outward flow of fusion-generated   energy supports the Sun ...
  • 06:56: ... those fragments collapsed further, kindling little  sparks of fusion reminiscent of an earlier ...
  • 14:14: ... episode, which features a  visit from Matt to explain nuclear fusion. ...

2021-12-29: How to Find ALIEN Dyson Spheres

  • 06:37: ... its life settles into an equilibrium state in which the outward flow of fusion-generated energy balances the inward crush of its own ...

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

  • 00:02: ... i could just fund anything i think we have to start by just getting fusion taken care of once and for all getting i mean seriously here's an ...

2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light

  • 04:03: ... necessary for the nuclear fusion reactions that power the sun, in some biological processes, and it’s ...

2021-08-18: How Vacuum Decay Would Destroy The Universe

  • 08:30: ... The ability for stars to form and undergo  nuclear fusion, and the ability for chemistry   to work as it does, depend ...

2021-08-10: How to Communicate Across the Quantum Multiverse

  • 15:46: ... this less likely because losing mass reduces the internal pressure, the fusion rate, etc. You can actually defuse a potential future supernova by ...

2021-08-03: How An Extreme New Star Could Change All Cosmology

  • 01:45: ... lives, they blast off their outer layers in their final fits of nuclear fusion. This exposes their naked cores, which by now are insanely hot nuggets of ...

2021-04-13: What If Dark Matter Is Just Black Holes?

  • 06:53: ... to allow the stars' ultra dense carbon and oxygen to undergo nuclear fusion. ...

2020-12-15: The Supernova At The End of Time

  • 02:39: ... hydrogen, bathing a young planetary system in the energy produced by its fusion ...
  • 08:29: ... process is called pycnonuclear fusion - and it will very VERY slowly convert the Sun’s core from carbon into ...
  • 10:15: ... the last stage of the pycnonuclear fusion process, two silicon nuclei fuse to produce nickel, and then one of the ...

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

  • 09:06: Energy flows from the fusion engine in the core to the surface.

2020-09-01: How Do We Know What Stars Are Made Of?

  • 10:20: ... Eddington himself had postulated the whole nuclear fusion thing just a few years earlier in 1920, but now knowing what stars are ...

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

  • 16:46: Instead you’re most likely to just get an explosion as thermonuclear fusion rips through the white dwarfs carbon and oxygen interior.

2020-08-17: How Stars Destroy Each Other

  • 01:22: ... storm of fusion ripped around the planet-sized white dwarf, spraying its atmosphere into ...
  • 03:30: They result when denser streams of matter hit the white dwarf and flare due to heat, but do not produce the storm of fusion of the classical nova.
  • 07:58: ... is a star not quite massive enough to generate its own energy by nuclear fusion. ...
  • 09:59: A runaway fusion reaction rips through the star, which explodes as a Type 1 supernova.

2020-07-20: The Boundary Between Black Holes & Neutron Stars

  • 04:50: Once it was the burning heart of the star - a fusion engine that allowed the star to resist the inward crush of gravity.

2019-11-11: Does Life Need a Multiverse to Exist?

  • 06:21: ... hydrogen - becomes unstable, eliminating one of the key steps in the fusion process inside stars - so stars like our sun wouldn’t burn at ...
  • 06:42: With weaker gravity, diproton-burning stars could last longer, and with stronger gravity, fusion could skip the deuterium step.
  • 07:05: The stability of atoms and the rate of fusion in stars and in the early universe depends on the balance between electromagnetism and the strong force.

2019-09-23: Is Pluto a Planet?

  • 06:54: ... giant orbs of gas aren’t massive enough to ignite nuclear fusion in their cores like a true star, but still seemed too massive to be ...

2019-09-16: Could We Terraform Mars?

  • 08:51: ... from abundant silicon in the crust, or build 10 or so million gigawatt fusion power ...

2019-07-15: The Quantum Internet

  • 14:31: Because Fusion reactors are only 20 years away.
  • 14:35: For those who don't find that hilarious, let me pedantically explain Cory's joke: fusion has been projected to be 20 years away for 50 or so years.

2019-07-01: Thorium and the Future of Nuclear Energy

  • 00:33: ... helium But that's enough to power the Sun for 10 billion years Practical fusion power stations are a holy grail of energy production, but are still a ...
  • 02:49: ... the core to secondary circuits that ultimately power turbine The actual fusion only happens in the reactor core Because that's where the moderator ...

2019-06-06: The Alchemy of Neutron Star Collisions

  • 00:34: ... table between carbon and iron were produced in onion shells by nuclear fusion in the cores of very massive stars during the last phases of their lives ...

2019-01-24: The Crisis in Cosmology

  • 04:45: ...absorb too much material from a binary partner Runaway fusion causes them to detonate.

2018-05-09: How Gaia Changed Astronomy Forever

  • 02:50: Location on this diagram can tell us about a star's mass, size, fusion activity, and even its past and future evolution.

2018-05-02: The Star at the End of Time

  • 02:21: ... the rate of fusion depends very sensitively on temperature, more massive stars with their ...
  • 03:31: As a result, the Sun will only have access to 10% of its mass for fusion fuel.
  • 03:40: Rivers of plasma flow from the core to the surface, carrying both energy and the helium produced in the fusion reactions.
  • 03:48: That helium gets mixed through the star, while new hydrogen is brought to the core for fusion.
  • 04:25: The heating core causes red dwarf fusion rates to increase by a factor of 10 or more, particularly towards the ends of their lives.
  • 05:08: So increasing the surface temperature allows a red dwarf to shed all of those excess photons produced by its rising fusion rate.

2018-03-07: Should Space be Privatized?

  • 10:45: As the hydrogen fuel in the sun's core gets diluted by helium, the fusion rate does decrease and the core shrink.
  • 10:52: But that re-ups the fusion rate again.
  • 10:54: In fact, to support the increased gravitational crush of the smaller core, the fusion rate has to be even higher than when it started.
  • 11:12: That means new hydrogen flows down to the core, while the helium produced in core fusion is mixed through the star.
  • 11:23: No new fuel is carried down to the core and the fusion products remain stuck there.
  • 11:42: When fusion switches off, the star contracts, until electron degeneracy pressure stops the collapse.

2018-02-21: The Death of the Sun

  • 01:31: ... [INAUDIBLE] life, I mean the period of core hydrogen fusion, when the steady flow of energy from the core provides consistent support ...
  • 02:07: As the last traces of hydrogen are slammed together into helium 4 nuclei, fusion will cease.
  • 02:14: That helium is useless as a fuel, at least for now, because helium fusion requires temperatures of around 100 million Kelvin.
  • 03:05: Density rises and shell fusion spikes.
  • 04:50: It expands again, and the corresponding lower density allows helium fusion to slow down.
  • 05:16: Finally, surrounding an inert carbon oxygen core are two fusing shells, helium fusion inside hydrogen fusion.
  • 07:02: Explosions of runaway fusion in the double burning shell blast away the outer layers, perhaps creating a beautiful planetary nebula.

2018-01-31: Kronos: Devourer Of Worlds

  • 06:21: It gets dragged down to the core by convection, where it's destroyed in a fusion reaction.

2018-01-24: The End of the Habitable Zone

  • 01:09: ... due to a delicate balance between the outer flow of energy produced by fusion in the core and the gravitational crush of its immense ...
  • 01:22: The rate of fusion of hydrogen into helium increases with the temperature and density of the core.
  • 01:28: ... was halted as soon as the core became dense enough, dense enough for fusion to produce exactly the energy to balance that gravitational ...
  • 01:49: As the sun's fuel gets diluted, you might expect fusion to slow down.
  • 02:06: ... increases the density and temperature of the core which increases fusion rate, once again re-establishing equilibrium between gravitational crush ...

2018-01-10: What Do Stars Sound Like?

  • 00:38: ... between the gravitational crush and the outward flow of energy from the fusion reactions in the ...
  • 07:17: ... red giant stars, asteroseismology has been used to determine the fusion activity in their dying cores, allowing us to learn just how close these ...

2017-09-28: Are the Fundamental Constants Changing?

  • 09:14: This uranium deposit underwent a natural fusion event 2 billion years ago.

2017-05-31: The Fate of the First Stars

  • 04:43: Now, the rate of nuclear fusion reactions is incredibly sensitive to temperature.
  • 04:52: But that results in a dramatic increase in fusion rate, and therefore, energy output.

2017-02-22: The Eye of Sauron Reveals a Forming Solar System!

  • 02:38: The protostar continues to collapse more slowly until eventually the core gets hot and dense enough to ignite in fusion.

2017-02-02: The Geometry of Causality

  • 13:57: Mike Cammiso asks whether nuclear fusion occurs inside accretion disks.
  • 14:09: Stars are so good at fusion, in part, because they're the cause of creating high densities.
  • 14:13: ... in which case you might get some weird stardust-like activity and some fusion. ...

2016-11-16: Strange Stars

  • 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies.

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

  • 05:13: Fusion engines might be a good candidate, because the fuel is abundant everywhere.

2016-07-27: The Quantum Experiment that Broke Reality

  • 11:33: You'd need around 75 Jupiters piled on top of each other to ignite sustained fusion in its core.

2016-06-01: Is Quantum Tunneling Faster than Light?

  • 04:52: Protons, neutrons, electrons, and alpha particles can quantum tunnel into nuclei in various types of fusion and particle capture phenomena.

2016-05-04: Will Starshot's Insterstellar Journey Succeed?

  • 01:44: Even for next generation fuels, like certain types of fusion, the propellant weight can be most of the craft weight at launch.

2016-04-27: What Does Dark Energy Really Do?

  • 04:04: When the star reaches a critical mass, a runaway fusion reaction obliterates the star as a supernova.

2016-04-13: Will the Universe Expand Forever?

  • 10:20: In fact, there are many different fusion reactions occurring in the cores of those dying high-mass stars.
  • 10:27: Some of the most common involve either adding helium-- that's helium capture-- or losing helium after another fusion reaction.
  • 10:49: ... However, there are many ways to build elements out of this sequence, in fusion reactions that just aren't quite as ...

2016-04-06: We Are Star Stuff

  • 03:28: ... the Big Bang, the entire universe was hot and dense enough for nuclear fusion, for protons to slam together hard enough to overcome the electrostatic ...
  • 07:49: All of the main ingredients of your own body were fusion shells in past supernovae.
  • 08:47: ... star and manages to accrete, to steal from it enough material, a runaway fusion reaction starts inside the white dwarf that completely obliterates ...

2016-03-16: Why is the Earth Round and the Milky Way Flat?

  • 07:11: Here the pressure comes from the upward flow of energy from the nuclear fusion engine in the core.

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

  • 07:03: ... this time, nuclear fusion raged across the cosmos, baking some of the existing protons into ...

2015-12-09: How to Build a Black Hole

  • 01:33: ... the last throes of a very massive star's life, increasingly frantic fusion in the interior produces one periodic table element after another, in ...
  • 01:49: The formation of that core represents the end of exothermic fusion.

2015-11-25: 100 Years of Relativity + Challenge Winners!

  • 01:57: ... pulsed fusion drive spacecraft is to intercept the asteroid in the 2029 pass and pull ...
  • 05:49: We know that our pulsed fusion drive has an exhaust velocity of 500 kilometers per second.
  • 06:55: ... still need to build the pulse fusion drive, but once we have that relatively simple piece of tech, you could ...

2015-10-22: Have Gravitational Waves Been Discovered?!?

  • 10:30: ... which scoops up this interstellar hydrogen and channels it into maybe a fusion engine to power your ...

2015-10-15: 5 REAL Possibilities for Interstellar Travel

  • 03:02: I'm talking option two, fusion.
  • 04:18: Fusion rockets, either pulse blasts like the Daedalus project or ongoing fusion.
  • 04:28: It's an awesome option and may actually happen, but the tech for contained fusion is only now emerging, and there are many difficult challenges.
  • 04:40: But fusion turns less than 1% of rest mass into energy.
  • 05:37: That's something like 50 times more energy per kilogram of fuel than the best fusion options.
  • 09:39: Now fusion engines are more sustainable, even if the tech is a minimum of 50 years away.
  • 10:39: It's likely between this and post fusion drives.

2015-05-27: Habitable Exoplanets Debunked!

  • 08:36: Tim Chapelle asked how both fusion and fission could end up releasing energy.
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