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2022-12-08: How Are Quasiparticles Different From Particles?

  • 01:19: Atoms are most stable with full valence shells, which means 8 electrons.
  • 13:28: ... - quanta of waves in that lattice, or skyrmions, which are localized, stable topological field configurations sort of like knots - all very important ...

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

  • 15:48: ... episode on the island of stability - the hypothetical collection of stable-ish elements beyond the end of the current periodic ...
  • 15:58: Feynstein 100 asks if stable heavy elements like the island of stability could exist, then shouldn't they be present on earth and be found already?
  • 16:12: Those elements are unlikely to be perfectly stable.
  • 16:43: These then decay into the first stable isotope, with some neutrons converting into protons on the way.
  • 17:23: The idea is that there may be a new way for quarks to form stable clumps.
  • 17:49: ... normal matter, and that this up-down-quark matter may lead to perfectly stable “nuclei” with atomic masses as low as ...

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

  • 04:34: The isotope of Carbon that also has 6 neutrons is called carbon-12 for its 12 total nucleons, and it’s perfectly stable.
  • 04:44: Now an atom with 6 protons and 8 neutrons is still carbon - carbon-14, but it’s not stable.
  • 05:48: Larger atomic number tends to yield fewer stable isotopes and shorter half-lives.
  • 07:59: For smaller nuclei - up to an atomic number of 20 - an even split of protons and neutrons is usually the most stable.
  • 08:27: It also doesn’t explain why there’s no stable isotope of technetium.
  • 08:45: You may remember the Octet Rule from your chemistry classes: If an electron shell has eight electrons it is stable.
  • 09:18: The closer a nucleus is to those numbers, the more stable it will be.
  • 09:54: Pairs of up-down nucleons form these stable-little spin-zero partnerships in so-called nuclear pairing interactions.
  • 10:13: Sure we can see that 43 is not a magic number of protons, nor is it even like its more stable neighbors Molybdenum and Ruthenium.
  • 10:23: But the nearby odd numbered elements like the 47-proton’d silver have perfectly stable isotopes.
  • 11:42: ... with a magic number of protons have more stable isotopes, and there tend to be more isotopes with a number of neutrons ...
  • 11:53: Patterns emerge, but not so as to give us clean rules for what is needed to yield a stable nucleus.
  • 13:37: These stable-ish elements would appear here on the graph from before.
  • 14:54: ... is another example - no stable isotopes, but we can breed it from uranium in nuclear reactors, where it ...

2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics?

  • 08:16: A smaller value would mean electrons were less tightly bound, making atoms and molecules less stable.

2022-04-27: How the Higgs Mechanism Give Things Mass

  • 11:37: ... the field has reached the base of this  new minimum we have a new stable vacuum ...

2022-02-23: Are Cosmic Strings Cracks in the Universe?

  • 04:51: ... sitting at a higher energy than it  needed. It was momentarily stable at that point,   just like a ball sitting at the top of a ...

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

  • 03:41: AKA an accretion disk, and switching on the quasar Quasars are not what you’d call stable.
  • 14:47: Some scalar field that may or may not have been the Higgs field, is thought to have dropped from a much higher value into a stable minimum.

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

  • 05:03: ... false vacuum is a so-called metastable state - it seems   stable as long as the field doesn’t learn about the more stable, lower ...

2021-05-25: What If (Tiny) Black Holes Are Everywhere?

  • 06:05: In which case the Hawking radiation ceases, and the black hole becomes stable.
  • 06:25: If that’s not an allowed transition, then the remnant will become stable.

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... these pulses are not just fast they're exquisitely regular with the most stable millisecond pulsars the exact instant of one of these ticks can be ...

2021-01-26: Is Dark Matter Made of Particles?

  • 09:03: ... if these can’t decay into Standard Model particles then they’d be stable and long lived- an almost perfect dark matter ...

2021-01-12: What Happens During a Quantum Jump?

  • 07:25: Level 3 is far more stable than level 2 - an electron that finds itself there may take many seconds to drop back down.

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

  • 08:29: ... will very VERY slowly convert the Sun’s core from carbon into the most stable form of matter - iron - over around 10^1500 ...
  • 08:59: All of this depends on protons themselves being fundamentally stable.
  • 09:13: But assuming protons are stable, we’ll reach a point where the universe consists of only iron stars and radiation.
  • 10:25: The result is iron-56 - the most stable element in the universe.
  • 10:50: ... means that a white dwarf - or now iron black dwarf - that was initially stable with a mass below the original Chandrasekhar limit could become unstable ...

2020-10-27: How The Penrose Singularity Theorem Predicts The End of Space Time

  • 01:58: ... only showed that, once so-contracted,  the resulting black hole was stable. ...

2020-10-05: Venus May Have Life!

  • 06:05: That means anywhere that the more stable phosphorus and hydrogen-containing molecules might be broken apart.

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

  • 06:52: These necklaces are probably not too stable - but that’s OK as long you can replicate them faster than they fall apart.
  • 07:18: ... could reconfigure them over and over until they find a state that is stable in the environment, combined with developing the ability to replicate ...

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

  • 00:00: ... in four what happened to super symmetry all these things marginalized stable all these fancy things and new quantum gravity time disappears um ...

2020-04-07: How We Know The Earth Is Ancient

  • 08:25: ... and 13 isotopes are stable, and so much more abundant. Carbon-14 exists on the surface of the earth ...
  • 08:42: ... gradually drops. By measuring the current C-14 content relative to the stable C12 and C13 content, the age of once-living material - including fossils ...

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

  • 05:49: ... to the event horizon it’s possible to orbit a black hole in a perfectly stable way. For a non-rotating black hole you can execute a stable circular ...
  • 06:48: ... name for the size of these innermost stable circular orbits is ... innermost stable circular orbit. Or ISCO. For a ...

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

  • 13:41: In any 2-body system, there are these 5 places that a third body can be placed and will stay in stable orbit.
  • 14:14: These would no longer be called "Lagrange points", but they are true stable or metastable 3-body orbits.

2020-01-20: Solving the Three Body Problem

  • 07:56: ... the center of a third body’s orbit. In the 90s Cris Moore discovered a stable figure-8 orbit of three equal masses. The numerical discovery of the ...
  • 10:05: ... hundreds of stable 3-body orbits are known - although it should be noted that besides the ...
  • 11:21: ... almost all three-body systems eject one of the bodies, leaving a nice, stable two-body system - a binary pair. Stone and Leigh found that they could ...

2019-11-18: Can You Observe a Typical Universe?

  • 14:56: ... the universe needs to last a reasonable amount of time, have stable regions and energy sources for those structures to form, and have some ...

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

  • 05:10: ... radiate away the excess energy it had on formation, settling down into a stable ...
  • 06:12: ... if it were stable, this stuff would be like superfuel for stars - meaning all stars in the ...

2019-10-21: Is Time Travel Impossible?

  • 04:08: This is how you do it: take one stable wormhole large enough to be traversed.
  • 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.
  • 05:00: The equations of GR do permit large wormholes, but they are definitely not stable.

2019-09-16: Could We Terraform Mars?

  • 17:32: ... the inflaton field would have had to have transitioned between two stable or semi-stable states that are a factor of 10^27 different in ...

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

  • 00:33: ... energy is fission Which means breaking very heavy nuclei into more stable small parts If we want to convert mass into energy, fission gives us the ...
  • 02:49: ... slowed to become so-called Thermal neutrons On the other hand the more stable Uranium 238 is only fissile to fast-moving neutrons and not at all to ...
  • 16:59: ... is that it changes how closely an objects can orbit the black hole in a stable ...
  • 17:49: ... orbit in the same direction as a black hole's rotation that can be stable much closer in but if they orbit in the opposite direction then the ...

2019-06-17: How Black Holes Kill Galaxies

  • 12:17: ... common enough that most of the galaxy gets a decent amount of all the stable products of neutron star ...
  • 13:30: ... the thing is, strange matter is probably only stable under extreme pressure Release it from the embrace of the neutron star ...
  • 13:47: Even if strange matter is stable as so called "Strangelets" These are electrically neutral, so they don't have an electromagnetic signature.

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

  • 02:47: ... hopelessly unstable once they break apart and beat a decay into semi stable elements meanwhile the inner part of the vortex is still bathed in a sea ...

2019-05-01: The Real Science of the EHT Black Hole

  • 07:10: That’s the innermost stable circular orbit – the ISCO – and it’s the closest you can get to the black hole and still orbit in a stable way.

2018-08-23: How Will the Universe End?

  • 06:09: But in short, protons have the most stable composite particles.
  • 09:44: Over infinite time, nothing is truly stable.
  • 10:03: In the end of this scenario, every atom in the universe must fuse or decay into iron, the most stable element on the periodic table.
  • 10:53: ... small, stable black holes are possible, then quantum tunneling should allow small ...

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

  • 08:20: Those planets will thaw as their star brightens and may enjoy billions of years of stable warmth.

2018-02-21: The Death of the Sun

  • 00:49: They live their lives fusing hydrogen to helium in their cores, shining bright and stable for as long as that hydrogen lasts.

2017-10-04: When Quasars Collide STJC

  • 07:58: That means they stall and fall into a stable binary orbits around each other.

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

  • 05:48: There are two stable configurations for this interaction-- the little bar magnet may be aligned with the orbital field, or opposite to it.
  • 05:55: Alignment with the field is the more stable state.
  • 12:34: Richard, thank you, and may your own fundamental constants remain stable and forever within a range that supports life as we know it.

2017-06-07: Supervoids vs Colliding Universes!

  • 09:13: In particular, its vacuum energy takes on a stable value.

2017-04-05: Telescopes on the Moon

  • 03:16: But on a platform as stable as the moon, it may be possible to construct a telescope mirror right there.
  • 08:56: The moon with its thin atmosphere, stable surface, and long nights is an astronomer's dream.

2017-03-15: Time Crystals!

  • 09:00: Time crystals with their resilient spin-flip cycle could be the next step in building stable quantum memory.
  • 10:45: Solano Felicio asks about the possibility of stable orbits when planets are so close together.

2017-03-01: The Treasures of Trappist-1

  • 02:13: ... planets have now settled into stable orbital resonances with each other, and that's a hint that they may have ...

2017-02-02: The Geometry of Causality

  • 12:58: Joan Eunice asks whether there's a spot near a quasar where a stable orbit could be created, and what would time dilation be like there?
  • 13:06: Well, the smallest stable orbit around a black hole is the so-called innermost stable circular orbit.

2016-11-30: Pilot Wave Theory and Quantum Realism

  • 12:59: Burak asks why quark/strange matter isn't found naturally in the universe given that it's supposed to be so stable.
  • 13:07: OK, so the hypothesis is that strange matter is the most stable matter in the universe.
  • 13:18: In that case, having one strange for every one up and one down quark is a very low energy state and so is very stable.
  • 14:07: ... of strange matter, these strangelets may even be expected to be more stable the larger they are, and so would grow over ...

2016-11-16: Strange Stars

  • 05:58: ... lower energy state means that strange matter may be the most stable form of matter in the universe, more stable even than iron, which is the ...
  • 06:10: A star made entirely of this stuff should be completely stable.

2016-08-24: Should We Build a Dyson Sphere?

  • 02:49: ... only kilometers or less in diameter and each with its own independent stable orbit around the ...

2016-08-10: How the Quantum Eraser Rewrites the Past

  • 14:15: ... our monetary economic systems to produce efficient stable and healthy societies that actually have the energy and collective ...

2016-07-06: Juno to Reveal Jupiter's Violent Past

  • 04:09: There were no stable orbits in this sort of environment.

2016-06-29: Nuclear Physics Challenge

  • 01:08: There are no stable isotopes of polonium, but one of the least stable is polonium 212.

2016-06-15: The Strange Universe of Gravitational Lensing

  • 08:38: There are no stable orbits this close to a black hole.

2016-05-25: Is an Ice Age Coming?

  • 10:33: We're in a long, stable, low-eccentricity phase.

2016-04-06: We Are Star Stuff

  • 03:46: Two protons, two neutrons, 12 quarks, a complicated but very stable marriage of particles.
  • 06:34: But iron is the most stable of all nuclei.

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

  • 04:43: Shouldn't those towers still be stable if they're only responsible for their own up-down equilibrium?

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

  • 04:02: Now, this rule is what keeps electrons in their separate stable orbits and, in turn, is part of what allows solid matter to have its structure.

2015-07-08: The Leap Second Explained

  • 00:41: ... redefined the SI second again based on atomic clocks since they're more stable, but the atomic clock second was calibrated to agree with the ephemeris ...

2015-03-18: Can A Starfox Barrel Roll Work In Space?

  • 07:58: Another possibility raise is that maybe there exists an exotic but more stable state of nuclear matter involving strange quarks.
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