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	2022-11-23: How To See Black Holes By Catching Neutrinos 03:50: ... the neutrino becomes a tau then it decays almost instantly, but an electron or muon will continue through the ice, ... 16:15: They’re likely to decay, but on a longer timescale than the other elements between the island and the current top of the periodic table. 16:23: So any that formed naturally, say in a supernova, may have decayed by now. 16:43: These then decay into the first stable isotope, with some neutrons converting into protons on the way. 16:50: There’s a limit to how large a nucleus you can make this way - and that’s when the decay timescale is shorter than the rate of neutron bombardment. 16:58: ... island of stability, you have to get through a region of extremely fast decay nuclei, and my guess is that known astrophysical processes can’t ... 16:50: There’s a limit to how large a nucleus you can make this way - and that’s when the decay timescale is shorter than the rate of neutron bombardment. 16:23: So any that formed naturally, say in a supernova, may have decayed by now. 03:50: ... the neutrino becomes a tau then it decays almost instantly, but an electron or muon will continue through the ice, ...
	2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table? 05:55: ... with more than 118 protons decay so quickly that we’ve never been able to detect one in the lab ... 07:21: If a nucleus gets too big, the strong force can’t keep things together and various types of nuclear decay become inevitable. 10:40: Why, for example, does Technetium-97 survive for 4 million years but Tc-96 decays in under an hour? 12:28: ... elements are extremely rare in nature, only appearing briefly in the decay chain of other, longer-lived unstable ... 10:40: Why, for example, does Technetium-97 survive for 4 million years but Tc-96 decays in under an hour?
	2022-09-21: Science of the James Webb Telescope Explained! 15:50: One of the clearest signatures of a Higgs boson decay is into four muons.
	2022-09-14: Could the Higgs Boson Lead Us to Dark Matter? 05:28: Or they may decay due to being hopelessly unstable, in which case we detect their decay products. 05:46: ... particles with electrical charge OR color charge can’t decay into Higgs bosons, because the Higgs itself doesn’t have such charge - ... 06:30: ... could potentially decay into dark matter particles, but if they do it’s going to be near ... 08:14: But once we create them, how could we possibly tell if a Higgs decays into dark matter? 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 11:59: This number tells you the fraction of times a Higgs decayed into particles that can’t be detected. 12:06: ... standard model predicts that up to 17% of Higgs bosons should decay into invisible neutrinos, so the null hypothesis would be for a ... 12:31: If this number holds up, then ,the Higgs could be decaying into new invisible particles! 12:38: The error bars on this measurement are still large, and so we need to watch more Higgs bosons decay. 05:28: Or they may decay due to being hopelessly unstable, in which case we detect their decay products. 11:59: This number tells you the fraction of times a Higgs decayed into particles that can’t be detected. 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle. 12:31: If this number holds up, then ,the Higgs could be decaying into new invisible particles! 08:14: But once we create them, how could we possibly tell if a Higgs decays into dark matter? 11:24: And the Higgs lives for only a fraction of a second before decaying. The hope is that sometimes it decays into a dark matter particle.
	2022-08-03: What Happens Inside a Proton? 13:36: ... QCD has accurately predicted many things,   from masses and decay frequencies of hadrons to the exotic properties of quark-gluon ...
	2022-07-20: What If We Live in a Superdeterministic Universe? 16:08: For example, do different color quarks decay the same way? 16:12: Actually yes, they do decay exactly the same way besides influencing the color charge of their decay products. 16:56: For example, Planck units, or the energies or masses or decay timescales of common particles and elements. 16:12: Actually yes, they do decay exactly the same way besides influencing the color charge of their decay products. 16:56: For example, Planck units, or the energies or masses or decay timescales of common particles and elements.
	2022-06-30: Could We Decode Alien Physics? 05:33: ... manifestation of this symmetry breaking. The classic example is the decay of the kaon particle,   which we’ve talked about in detail ...
	2022-06-01: What If Physics IS NOT Describing Reality? 13:41: ... with stars, kicking them up to  higher orbits while its own orbit decays. In this   way it’ll spiral towards the center and ...
	2022-05-04: Space DOES NOT Expand Everywhere 13:50: ... depends on its mass. In the case of the W boson, the particle actually decays too quickly to measure its mass “directly”, but you can measure the ...
	2022-04-27: How the Higgs Mechanism Give Things Mass 11:37: ... from the central bump to  the valley is an example of vacuum decay,   and we saw how this can lead to the creation  of cosmic strings in ...
	2022-03-16: What If Charge is NOT Fundamental? 14:58: And the rho meson truffles .. but eat them before they decay in 10^-24 seconds.
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 18:29: A few of you asked how it is that a topological defect can decay.
	2022-02-23: Are Cosmic Strings Cracks in the Universe? 04:51: ... towards the new vacuum state - we call this vacuum   decay. Neighboring points in a field drag on each  other, pulling them ... 05:59: ... Higgs field formed strings. Remember   that the vacuum decayed in a random  direction towards this circular valley.   ... 08:50: ... between the nucleation event   and the completion of vacuum decay and then the  expanding universe stretched them up to the ... 10:09: ... waves. In this way cosmic strings  shed energy, and so they slowly decay away.   Eventually they vanish as the Higgs field ... 12:19: ... support of string theory. We also expect  cosmic superstrings to decay less quickly   because they don’t chop into loops as ... 10:09: ... waves. In this way cosmic strings  shed energy, and so they slowly decay away.   Eventually they vanish as the Higgs field smooths  itself out ... 04:51: ... towards the new vacuum state - we call this vacuum   decay. Neighboring points in a field drag on each  other, pulling them towards the ... 05:59: ... Higgs field formed strings. Remember   that the vacuum decayed in a random  direction towards this circular valley.   ...
	2022-02-16: Is The Wave Function The Building Block of Reality? 01:24: ... atom attached to a vial of poison gas. The atom has a 50-50 chance of decaying, triggering the release of gas and so killing the cat. Prior to opening ...
	2021-10-20: Will Constructor Theory REWRITE Physics? 12:30: ... explicitly   defined as motion across this exponential  decay to the other side of the barrier.   As for whether we can think of ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 00:32: It describes how quantum particles are able to move across seemingly impenetrable barriers - for example, when atomic nuclei decay. 02:22: In radioactive decay, particles that should never have enough energy to escape the nucleus are found to leak out. 03:44: ... into one of those two states - either business as usual, or a nuclear decay. ... 03:55: We see tunneling everywhere, in radioactive decay of course, but this tunneling also drives many other important processes. 02:22: In radioactive decay, particles that should never have enough energy to escape the nucleus are found to leak out.
	2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe 06:38: ... of earth, we might find a   nucleus like Zinc-80, which would decay in  half a second on earth by ejecting neutrons.   Nuclei ...
	2021-09-07: First Detection of Light from Behind a Black Hole 12:46: And then the episode on how vacuum decay could destroy the universe .. or universes, if the ideas in the first episode are right. 14:25: ... von Schweinitz and TBE_pryce both commented that the vacuum decay scenario sounds a lot like the big bang - what with it producing an ... 14:39: In fact cosmic inflation - the event that many physicists put the bang in the big bang - IS a type of vacuum decay. 15:03: ... means a new vacuum decay event now wouldn’t yield universe whose interior is expanding quickly - ... 15:34: How big does the vacuum decay bubble need to be in order to propagate. 15:03: ... means a new vacuum decay event now wouldn’t yield universe whose interior is expanding quickly - in the ... 14:25: ... von Schweinitz and TBE_pryce both commented that the vacuum decay scenario sounds a lot like the big bang - what with it producing an expanding ...
	2021-08-18: How Vacuum Decay Would Destroy The Universe 01:00: ... of physics across the universe.   That mechanism is vacuum decay, and  some physicists think it’s ... 01:15: ... to give you a crude picture - vacuum  decay looks like a bubble of annihilation   that expands at the ... 08:08: ... First up, everything gets fried. The energy  released in the decay of the Higgs field fills   the expanding bubble with a hot ... 08:30: ... also   add that there are other possible types  of vacuum decay beyond Higgs field decay.   For example, there may be weird ... 09:15: ... vacuums - then we’ll talk about whether   that vacuum might decay. Assuming the Higgs field really does have multiple minima, the ... 10:10: ... so the next question is could the vacuum really decay? As long as decay is possible,   it’s inevitable. At any ... 10:54: ... colliders like the LHC might nucleate a vacuum   decay bubble. But that was unfounded. After all, Earth is constantly ... 11:34: ... it’s very unlikely  that a vacuum decay bubble   will reach us in the lifespan of our species,  ... 12:07: ... this leads to one more comforting fact. If the vacuum does decay inside our cosmic horizon   we’ll never see it coming. Because ... 01:00: ... of physics across the universe.   That mechanism is vacuum decay, and  some physicists think it’s ... 09:15: ... vacuums - then we’ll talk about whether   that vacuum might decay. Assuming the Higgs field really does have multiple minima, the question ... 10:54: ... colliders like the LHC might nucleate a vacuum   decay bubble. But that was unfounded. After all, Earth is constantly being ... 11:34: ... it’s very unlikely  that a vacuum decay bubble   will reach us in the lifespan of our species,  let alone your own ... 12:07: ... this leads to one more comforting fact. If the vacuum does decay inside our cosmic horizon   we’ll never see it coming. Because no ... 11:34: ... But as long as we’re far enough away we’re safe. If the vacuum decay starts beyond several billion   light years, the accelerating ... 07:01: ... entire universe   down into the true vacuum. This is vacuum decay. It’s a phase transition of the quantum fields.   In fact it has a ... 00:00: ... going to end. But of all the  possible ends of the universe vacuum decay   would have to be the most thorough - because  it could totally ... 08:08: ... let’s review the horrors that  would result from vacuum decay.   First up, everything gets fried. The energy  released in the decay ... 08:30: ... there are other possible types  of vacuum decay beyond Higgs field decay.   For example, there may be weird fields within string theory that ... 12:07: ... have left - perhaps   mere billions of years - before vacuum decay swallows this fragile and metastable space ...
	2021-07-13: Where Are The Worlds In Many Worlds? 00:20: ... one branch of the splitting quantum multiverse a radioactive nucleus decay, in another it doesn’t; in one “world” a quantum event in your brain ...
	2021-06-23: How Quantum Entanglement Creates Entropy 13:44: ... and the fact that some of the rocket-stage debris orbits would have decayed. That still leaves it at   a significant fraction, but not 40%. ...
	2021-06-09: Are We Running Out of Space Above Earth? 04:24: It produces a drag that causes orbits to slowly decay. 05:37: The only way this stuff gets cleaned up is if its orbit decays. 05:41: I already mentioned that orbits decay due to interaction with the upper reaches of Earth’s atmosphere. 05:53: This is another positive feedback loop - orbital decay accelerates until the satellite finally burns in a glorious blaze of re-entry. 06:18: That’s annoying, but orbital decay is the most important process for cleaning low-earth orbit of defunct satellites and debris. 06:26: Ultimately, the Kessler Syndrome can be avoided if orbital decay cleans up low-earth orbit faster than new launches and new collisions fill it. 08:43: That debris then decays in orbit. 10:53: I should add that StarLink will be in very low orbit, and so has a fast decay time - under 5 years. 05:53: This is another positive feedback loop - orbital decay accelerates until the satellite finally burns in a glorious blaze of re-entry. 06:26: Ultimately, the Kessler Syndrome can be avoided if orbital decay cleans up low-earth orbit faster than new launches and new collisions fill it. 10:53: I should add that StarLink will be in very low orbit, and so has a fast decay time - under 5 years. 05:37: The only way this stuff gets cleaned up is if its orbit decays. 08:43: That debris then decays in orbit.
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 07:51: A black hole with a mass of a billion tons or lower could have decayed to a relic by now - and fortunately there’s a way to make those.
	2021-04-21: The NEW Warp Drive Possibilities 14:57: For the tau, the focus is in watching its decay products. 15:01: ... example, the energy distribution of those decays products are sensitive to the complex interactions with virtual ... 14:57: For the tau, the focus is in watching its decay products. 15:01: ... example, the energy distribution of those decays products are sensitive to the complex interactions with virtual ...
	2021-04-07: Why the Muon g-2 Results Are So Exciting! 07:11: Muons are nice, because they're easily produced in radioactive decay. 10:02: The frequency of the precession also governs the energy of the particles that these muons decay into. 10:19: ... a new particle based on a slight bump at a particular energy of the decay ...
	2021-03-23: Zeno's Paradox & The Quantum Zeno Effect 01:27: ... events - like the electrons moving between atomic energy levels, or the decay of atomic nuclei, can be frozen through the simple act of ... 05:23: ... in principle this would also work for radioactive decay, even chemical reactions The basic idea of the quantum Zeno effect was ... 07:47: ... that allows particles to “teleport” out of nuclei during nuclear decay. ...
	2021-02-24: Does Time Cause Gravity? 09:20: ... epoch - fluctuations in the so-called inflaton field, or in the final decay of those inflatons at the end of ...
	2021-01-26: Is Dark Matter Made of Particles? 09:03: ... while normally heavy things tend to decay to lighter things, if these can’t decay into Standard Model particles ...
	2021-01-12: What Happens During a Quantum Jump? 07:52: Then, after a period of time, the electron decays and fluorescence starts again. 08:02: And the downward jumps when the electron decayed out of level 3 appeared to occur at completely random times. 07:52: Then, after a period of time, the electron decays and fluorescence starts again.
	2020-12-22: Navigating with Quantum Entanglement 13:37: ... elements are observed as emission or absorption lines, the way the light decays over time, and other ... 14:12: ... are two broad scenarios - first, if protons do NOT decay then quantum tunneling will cause the neutron star to collapse into a ... 14:34: ... the other hand if protons DO decay then the small proton content of neutron stars will decay into pions and ... 14:44: The neutron star will then expand, allowing some neutrons to convert back into protons, which can themselves decay. 14:50: The Star may go through a phase as a white - or perhaps now black dwarf and will continue to evaporate due to proton decay. 15:21: So yeah, Russell’s teapot either evaporates as its protons decay, or quantum tunnels into an iron teapot - is that a kettle? 13:37: ... elements are observed as emission or absorption lines, the way the light decays over time, and other ...
	2020-12-15: The Supernova At The End of Time 09:02: ... protons can decay, then the entire white dwarf will vaporize into a subatomic mist in a ...
	2020-12-08: Why Do You Remember The Past But Not The Future? 04:02: ... many, many times the current age of the universe and the asteroid will decay into a mist of subatomic ... 04:41: Let’s say this process is reversible - the particle physics jury is still out on whether protons can decay - but for this episode they can. 05:38: If the laws of physics can exactly reconstruct the formation of the proton, those same laws can be used to project when the proton will decay. 05:53: For this lone proton, its formation and decay are identical events and it's fair to say this whole sequence has no arrow of time. 06:20: And then in the far, far future the rock decays. 07:18: It’s fully formed but hasn’t started to decay yet. 07:33: If the rock never interacts with any external influence and just decays over time, then in principle we could calculate that decay. 04:41: Let’s say this process is reversible - the particle physics jury is still out on whether protons can decay - but for this episode they can. 06:20: And then in the far, far future the rock decays. 07:33: If the rock never interacts with any external influence and just decays over time, then in principle we could calculate that decay.
	2020-11-18: The Arrow of Time and How to Reverse It 00:54: ... you drop it, but will never spontaneously reassemble. Our whole universe decays in the inexorable rise in entropy as time ticks forward. The other place ... 10:34: ... The Higgs field sits at a non-zero vacuum energy so could potentially decay to zero, or even to a lower non-zero state non-zero ... 10:58: ... the universe went thorugh another phase transition - a vacuum decay - then the weak interaction would fundamentally change - to become a ... 11:09: given we hgaven't actually done a vacuum decay eposide yet I'll save my deep dive into this for then. 10:58: ... the universe went thorugh another phase transition - a vacuum decay - then the weak interaction would fundamentally change - to become a ... 11:09: given we hgaven't actually done a vacuum decay eposide yet I'll save my deep dive into this for then. 00:54: ... you drop it, but will never spontaneously reassemble. Our whole universe decays in the inexorable rise in entropy as time ticks forward. The other place ...
	2020-11-04: Electroweak Theory and the Origin of the Fundamental Forces 01:02: You may have heard that it’s the force responsible for some types of radioactive decay. 01:11: Beta decay is when a neutron turns into a proton by emitting an electron and neutrino. 01:24: It’s one of the main ways radioactive nuclei decay - the other being alpha decay, where the emitted “alpha particle” is really a helium-4 nucleus. 01:46: Enrico Fermi made the first attempt at a full quantum description of beta decay with his ‘four fermion’ interaction. 01:24: It’s one of the main ways radioactive nuclei decay - the other being alpha decay, where the emitted “alpha particle” is really a helium-4 nucleus.
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 03:13: ... or CP, also fell, with the observation of the peculiarity in the decay of ... 05:43: ... all the time in nature - for example in the Sun, or in radioactive decay, or when cosmic rays hit the atmosphere, which is how antimatter was ...
	2020-06-30: Dissolving an Event Horizon 06:31: ... - in the far distant future, even if all particles in the universe decay, we may be left with only radiation and these naked, charged ... 07:15: Stuff doesn’t normally fall straight into a black hole - it spirals in as its orbit decays.
	2020-06-15: What Happens After the Universe Ends? 00:45: ... to to an unthinkably large size, and every black hole and particle has decayed into faint radiation .... that infinite stretch of space and time is ... 07:06: ... all stars will die and their remnants will decay - black holes will evaporate by Hawking radiation, and particles of ... 07:38: Penrose speculates that mass itself may not be a fundamental property, and may eventually decay to leave massless electrons, etc. 07:50: But it’s not absurd to imagine their mass decaying. 08:57: ... the way, a change in the nature of the Higgs field - if it decayed to a lower energy - could eliminate elementary particle masses in the ... 07:06: ... all stars will die and their remnants will decay - black holes will evaporate by Hawking radiation, and particles of matter ... 00:45: ... to to an unthinkably large size, and every black hole and particle has decayed into faint radiation .... that infinite stretch of space and time is ... 08:57: ... the way, a change in the nature of the Higgs field - if it decayed to a lower energy - could eliminate elementary particle masses in the ... 07:50: But it’s not absurd to imagine their mass decaying.
	2020-05-04: How We Know The Universe is Ancient 00:17: ... we learned how we calculate the age of the Earth based on radioactive decay in its most ancient ...
	2020-04-14: Was the Milky Way a Quasar? 04:22: The neutral pion will then decay into a pair of gamma rays. 04:49: The gamma rays produced by neutral pion decay from these cosmic ray collisions tend to drop off in intensity towards higher energies. 14:47: ... U-238 has a shorter half life so first it decays quickly in the first couple of billion years, then the U-235 dominates ...
	2020-04-07: How We Know The Earth Is Ancient 06:47: ... discovered that certain elements released energy from radioactive decay at an ever-decreasing rate. And that some of those elements would slowly ... 07:17: ... chunks of the Earth through radiometric dating. Unstable atomic nuclei decay into lighter nuclei by splitting or by ejecting particles. The rate of ... 07:58: ... known example is carbon dating. In this case we’re interested in the decay of carbon-14 - that’s the version or “isotope” of carbon with 8 ... 09:13: ... for measuring the age of the earth is uranium-lead dating. Uranium decays on much longer timescales - 710 million years for the U-235 isotope and ... 09:33: ... repelling lead. So any lead you find in those crystals came from uranium decay. ... 07:17: ... amount of time for a given radioactive nucleus to have a 50% chance of decaying; or equivalently, the amount of time it takes for half of a large number ... 09:13: ... years for the U-235 isotope and 4.5 billion years for U-238, with both decaying to different isotopes of ... 07:58: ... version or “isotope” of carbon with 8 neutrons. It’s radioactive, and decays with a half-life of 5,700 ... 09:13: ... for measuring the age of the earth is uranium-lead dating. Uranium decays on much longer timescales - 710 million years for the U-235 isotope and ...
	2020-03-16: How Do Quantum States Manifest In The Classical World? 00:20: ... box with a vial of deadly poison that’s released on the radioactive decay of an ... 00:44: ... atom’s wavefunction can be in a superposition of states - simultaneously decayed or not decayed. So is the cat’s wavefunction also in a superposition of ... 04:28: ... so-called Einstein-Podolsky-Rosen, or EPR paradox. A high energy photon decays into an electron and a positron. These particles both have spin values ... 00:44: ... atom’s wavefunction can be in a superposition of states - simultaneously decayed or not decayed. So is the cat’s wavefunction also in a superposition of ... 04:28: ... so-called Einstein-Podolsky-Rosen, or EPR paradox. A high energy photon decays into an electron and a positron. These particles both have spin values ...
	2020-03-03: Does Quantum Immortality Save Schrödinger's Cat? 02:25: As a refresher: a cat is in an opaque box with a vial of deadly poison, which is released on the radioactive decay of an atom. 02:33: ... a totally random 50-50 chance of the radioactive decay over a certain period of time - that means the quantum wavefunction of ... 03:32: ... the vial to many atoms - so that the poison is released if any of them decay. ... 03:41: Let’s be specific - there are 100 polonium-212 atoms, with half-life 300 microseconds - so each atom has a 50% chance of decaying in that time. 04:05: ... bad I guess - that chance that any one atom does NOT decay in that 300 microseconds is 50-50, but the chance that none of the 100 ... 02:33: ... wavefunction of the atom splits equally - the atom is simultaneously decayed and not decayed until we observe ... 03:41: Let’s be specific - there are 100 polonium-212 atoms, with half-life 300 microseconds - so each atom has a 50% chance of decaying in that time.
	2020-02-11: Are Axions Dark Matter? 08:05: ... would do this by generating pairs of virtual quarks which then decay into photons - the so-called Primakoff effect. This would look like an ...
	2020-02-03: Are there Infinite Versions of You? 08:17: But universes with large vacuum energies will exponentially expand, until that vacuum energy decays to lower values in smaller regions within.
	2020-01-13: How To Capture Black Holes 04:50: ... hole to gas, slowing the black hole down a bit and causing its orbit to decay - much like how a satellite’s orbit will decay if it’s too close to ...
	2020-01-06: How To Detect a Neutrino 03:17: ♪ ♪ Those pions quickly decay into muons and muon neutrinos. 08:31: ... ♪ ♪ DR. DON (voiceover): neutrinos in the early universe may have decayed into other matter particles, ♪ ♪ with matter neutrinos producing ...
	2019-10-07: Black Hole Harmonics 04:19: A harmonic oscillation that decays over time is called a quasinormal mode. 10:19: ... by checking whether the frequency of oscillations and the time for the decay of those oscillations agrees perfectly with Einstein’s ... 04:19: A harmonic oscillation that decays over time is called a quasinormal mode.
	2019-09-30: How Many Universes Are There? 06:09: But what if the inflaton field retained just a tiny bit of energy after its decay?
	2019-08-19: What Happened Before the Big Bang? 03:54: When that state decays, potential energy is released as real particles, ending inflation, and re-heating the universe in an expanding bubble. 04:02: The random nature of this version of inflaton decay means that many such bubbles should form, ie. multiple universes exist. 08:06: ... should grind to a halt over large regions as the inflaton field decays As I mentioned, small fluctuations in the Inflaton field would lead to ... 08:58: That region would then continue to decay spawning new universes, but also spawning new inflating regions. 11:46: Then an ocean of inflaton particles released by the decaying inflaton field turned into extremely energetic particles and radiation. 08:58: That region would then continue to decay spawning new universes, but also spawning new inflating regions. 11:46: Then an ocean of inflaton particles released by the decaying inflaton field turned into extremely energetic particles and radiation. 03:54: When that state decays, potential energy is released as real particles, ending inflation, and re-heating the universe in an expanding bubble. 08:06: ... should grind to a halt over large regions as the inflaton field decays As I mentioned, small fluctuations in the Inflaton field would lead to ... 03:54: When that state decays, potential energy is released as real particles, ending inflation, and re-heating the universe in an expanding bubble.
	2019-08-06: What Caused the Big Bang? 10:26: ... disperse their energy into the other quantum fields. The inflatons decay into the familiar particles of the standard model - quarks, electrons, ...
	2019-07-15: The Quantum Internet 12:15: ... because it decays to protactinium isotope that itself decays to emit a very high energy ... 12:29: This is a good point, it's not quite foolproof because the decay products leading to protactinium can potentially be separated and removed. 14:07: ... U-239 is unstable and the extra neutron quickly decays into a proton, emitting an electron and a neutrino, bumping it one up on ... 12:29: This is a good point, it's not quite foolproof because the decay products leading to protactinium can potentially be separated and removed. 12:15: ... because it decays to protactinium isotope that itself decays to emit a very high energy ... 14:07: ... U-239 is unstable and the extra neutron quickly decays into a proton, emitting an electron and a neutrino, bumping it one up on ...
	2019-07-01: Thorium and the Future of Nuclear Energy 02:49: ... not naturally fissile But it is fertile upon absorption of a neutron it decays into protactinium-233 and then into uranium-233 And U-233 is nicely ...
	2019-06-17: How Black Holes Kill Galaxies 12:39: ... picked up a silly mistake I said that the half-life is the average decay time of a radioactive element It's ... 12:49: It's the amount of time for half of the given sample to decay. 13:30: ... from the embrace of the neutron star and all the strange quarks probably decay into boring old up and down quarks which would join together to become ... 14:00: But you might see the result of it's decay a particular spectrum of radiation and cosmic rays. 12:39: ... picked up a silly mistake I said that the half-life is the average decay time of a radioactive element It's ...
	2019-06-06: The Alchemy of Neutron Star Collisions 00:34: ... the rapid part is because neutrons are captured faster than nuclei can decay making it possible to build very heavy nuclei it's a cool story it would ... 02:47: ... breaks up into droplets of neutrons many neutrons rapidly undergo beta decay transforming into a proton after ejecting an electron and a neutrino the ... 00:34: ... the rapid part is because neutrons are captured faster than nuclei can decay making it possible to build very heavy nuclei it's a cool story it would be ... 02:47: ... hole presumably doomed to fall into the event horizon but that same beta decay process the converted neutrons back to protons also provides the mechanism for ...
	2019-03-13: Will You Travel to Space? 13:51: Electrons escape their orbits by quantum tunneling, and protons themselves may eventually decay.
	2019-01-16: Our Antimatter, Mirrored, Time-Reversed Universe 00:42: ... the experiment that first proved this found that cobalt-60 nuclei decay by splitting an electron out in the opposite direction to their nucleus ... 01:48: ... momenta that will align with a magnetic field let's say upwards so the decay electrons travel ... 02:02: ... the cobalt atoms with their parity inverted counterparts but now the decay electrons travel upwards with the nuclear spin and away from the ... 03:02: ... nuclei so in our mirror reflected antimatter clock the direction of the decay electrons are flipped once due to the mirror reflection and once due to ... 10:54: ... of a physical system - an explosion becomes an implosion and particle decay becomes particle creation. You're not rewinding time, you're not ... 01:48: ... momenta that will align with a magnetic field let's say upwards so the decay electrons travel ... 02:02: ... the cobalt atoms with their parity inverted counterparts but now the decay electrons travel upwards with the nuclear spin and away from the detector such a ... 03:02: ... nuclei so in our mirror reflected antimatter clock the direction of the decay electrons are flipped once due to the mirror reflection and once due to the switch ... 01:48: ... momenta that will align with a magnetic field let's say upwards so the decay electrons travel ... 02:02: ... the cobalt atoms with their parity inverted counterparts but now the decay electrons travel upwards with the nuclear spin and away from the detector such a clock ... 03:02: ... given their short lifetimes and yet a small but significant number of decay products from KS particles were found at the far end the only explanation is that ...
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... in all respects same spin same mass same electric charge but different decay products the tower decayed into three pylons also miss ons while the ...
	2018-12-06: Did Life on Earth Come from Space? 00:37: ... air or nutrients and are remarkably resistant to radiation damage or DNA decay bacterial endospores have been rejuvenated after up to six years ...
	2018-11-21: 'Oumuamua Is Not Aliens 14:00: ... make it all the way through the planet, hence the surprise at seeing the decay products of a high energy tau neutrino that had appeared to pass right ...
	2018-11-14: Supersymmetric Particle Found? 05:53: It spots neutrinos when they're decayed or electrons, muons, or tau particles, which in turn produce visible light as they streak through the ice. 06:37: ... an ultra high energy neutrino decays in the ice anywhere within 700 kilometers of ANITA, the resulting radio ... 08:05: It produces a Cherenkov burst when it's created and then a second burst when it decays into a shower of secondary particles. 09:15: The stau is theoretically capable of zipping straight through the earth before decaying into a regular tau lepton on the other side. 05:53: It spots neutrinos when they're decayed or electrons, muons, or tau particles, which in turn produce visible light as they streak through the ice. 09:15: The stau is theoretically capable of zipping straight through the earth before decaying into a regular tau lepton on the other side. 06:37: ... an ultra high energy neutrino decays in the ice anywhere within 700 kilometers of ANITA, the resulting radio ... 08:05: It produces a Cherenkov burst when it's created and then a second burst when it decays into a shower of secondary particles.
	2018-11-07: Why String Theory is Right 16:28: You have a box containing a vial of poison connected to a radioactive isotope that could either decay or not, releasing the poison.
	2018-10-18: What are the Strings in String Theory? 08:51: These last properties are important because it gives a mechanism for the particles of string theory to interact and to decay into other particles.
	2018-10-10: Computing a Universe Simulation 09:33: Protons will have started to decay by the time we simulate last Monday.
	2018-09-12: How Much Information is in the Universe? 13:59: ... the fact that the hypothetical proton decay time is 10 to the power 40 years, Vinay K asks if a proton created in, ... 14:17: That 10 to the 40 years is a crude estimate of the protons half-life, assuming it decays at all, which it might not. 14:27: ... but can be used for anything that has a constant probability of decaying in a given amount of ... 14:35: So the half-life is the amount of time it takes for something to have a 50% chance of decaying at some point during that time. 14:43: The actual amount of time it takes to decay is random, and there's a constant probability of it happening at every set interval. 14:51: So if these decays happen at all, then after 10 to the power of 40 years, every proton in the universe will have had a 50% chance of decaying. 15:00: That means around 50% of them will have decayed, and many of those will have decayed much sooner than 10 to the 40 years. 15:07: After another 10 to the 40 years, 50% of the remaining protons will have decayed, and so on. 13:59: ... the fact that the hypothetical proton decay time is 10 to the power 40 years, Vinay K asks if a proton created in, say, ... 15:00: That means around 50% of them will have decayed, and many of those will have decayed much sooner than 10 to the 40 years. 15:07: After another 10 to the 40 years, 50% of the remaining protons will have decayed, and so on. 14:27: ... but can be used for anything that has a constant probability of decaying in a given amount of ... 14:35: So the half-life is the amount of time it takes for something to have a 50% chance of decaying at some point during that time. 14:51: So if these decays happen at all, then after 10 to the power of 40 years, every proton in the universe will have had a 50% chance of decaying. 14:17: That 10 to the 40 years is a crude estimate of the protons half-life, assuming it decays at all, which it might not. 14:51: So if these decays happen at all, then after 10 to the power of 40 years, every proton in the universe will have had a 50% chance of decaying.
	2018-08-30: Is There Life on Mars? 11:17: ... large organic molecules called kerogens, which are often produced in the decay of once living ...
	2018-08-23: How Will the Universe End? 01:19: ... are many fascinating ways in which the universe can still decay to increasingly less interesting states-- or, scientifically, many ways ... 06:03: Do protons decay? 06:18: But there are several beyond the standard-model mechanisms that would allow them to decay into positrons, neutrinos, and gamma ray photons. 06:25: This decay has never been detected. 06:28: But failed attempts to spot it tell us it must take at least 10 to the power of 34 years for a proton to have a 50% chance of decaying. 06:37: Theory says that if protons decay at all, this half-life could be up to 10 to the power of 37 years. 07:06: If protons decay, black holes would be the only mass of bodies left in the universe after 10 to the power 40 years. 09:22: Now, before we finish, we have to take a step back and ask, what if protons don't decay? 09:54: ... lighter than iron to fuse together, while elements heavier than iron decay. ... 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. 10:11: Black dwarfs decay into iron stars-- still degenerate and insanely dense, but now perfect balls of iron. 11:31: Again, that's if protons don't decay. 12:23: Vacuum decay may drop the universe to an even lower energy state, wiping out the laws of physics as we know them. 07:06: If protons decay, black holes would be the only mass of bodies left in the universe after 10 to the power 40 years. 06:28: But failed attempts to spot it tell us it must take at least 10 to the power of 34 years for a proton to have a 50% chance of decaying.
	2018-07-25: Reversing Entropy with Maxwell's Demon 00:19: The second law of thermodynamics, the law that entropy must on average increase, has been interpreted as the inevitability of the decay of structure.
	2018-07-18: The Misunderstood Nature of Entropy 00:07: ... providing the driving force for the development of structure as well as decay and also excusing the messiness of your ... 02:28: Around a half century after Carnot, Rudolf Clausius was inspired to quantify this tendency of heat energies to decay over time, enter entropy. 10:33: We talked a little about this in our episode on the physics of life, where we saw how entropy drives both the increase and decay of complexity.
	2018-06-20: The Black Hole Information Paradox 13:07: That charge only decays if the black hole is left to its own devices.
	2018-05-02: The Star at the End of Time 01:15: For life to stave off rising entropy and decay, energy must flow.
	2018-04-11: The Physics of Life (ft. It's Okay to be Smart & PBS Eons!) 00:52: The universe tends toward disorder, decay, and equilibrium.
	2017-12-20: Extinction by Gamma-Ray Burst 01:01: ... out of the last stars, or the evaporation of the last black hole and decay of the last ...
	2017-11-22: Suicide Space Robots 09:11: It's decaying plutonium power source will only support operations to 2025.
	2017-11-08: Zero-Point Energy Demystified 02:27: The universe tends towards disorder, and so a highly unusual arrangement will decay over time. 02:40: We harness that decay of order whenever we draw energy from a system.
	2017-09-28: Are the Fundamental Constants Changing? 09:19: Scientists are analyzing the remaining decay products to see if Alpha was smaller when the event took place.
	2017-07-19: The Real Star Wars 11:27: ... official line is that the satellite was decaying from orbit, and the purpose of its destruction was to avoid the unlikely ... 11:39: ... as dangerous as the Chinese explosion because that debris' orbit will decay much more ... 11:27: ... official line is that the satellite was decaying from orbit, and the purpose of its destruction was to avoid the unlikely ...
	2017-07-12: Solving the Impossible in Quantum Field Theory 11:08: ... matter-anti-media creation and annihilation, to all sorts of decay ...
	2017-05-17: Martian Evolution 02:54: So what traits are likely to be enhanced or developed on Mars and which are likely to decay?
	2017-04-26: Are You a Boltzmann Brain? 05:30: The black holes will evaporate, the last proton will decay, and all of that cool stuff will cease.
	2017-04-19: The Oh My God Particle 01:48: High energy particles, electrons, and small atomic nuclei, as well as gamma rays, are ejected when heavier radioactive elements decay.
	2016-12-21: Have They Seen Us? 14:55: But real black holes decay.
	2016-11-30: Pilot Wave Theory and Quantum Realism 13:34: In that case, any mass of strange quarks will decay into the lighter up or down quarks. 15:53: ... it would expand into a gas cataclysmically and the neutrons would decay to protons and electrons and an awful lot of ...
	2016-11-16: Strange Stars 04:33: We can study its nature based on the particles that decay from it.
	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. 02:51: That radioactive decay is a purely quantum process. 03:00: It has both decayed and not decayed. 05:23: ... if the family of possible states extends beyond the radioactive decay, beyond the cat, and includes the observer and, indeed, the entire ... 05:33: ... we're part of an entire quantum timeline in which the radioactive decay and subsequent poisoning never ... 03:00: It has both decayed and not decayed. 02:40: A machine containing a radioactive element is set to shatter the flask in the event that the radioactive element decays.
	2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer 01:09: It's as though something with a mass energy equivalence of 17 MEV was decaying into those particles. 01:39: But this excess in the beryllium-8 decay is not slight. 03:25: ... the decay product of such a transition is very weakly interacting, these particles ... 01:09: It's as though something with a mass energy equivalence of 17 MEV was decaying into those particles.
	2016-07-20: The Future of Gravitational Waves 05:41: ... of the nucleus of a polonium-212 atom, causing the atom's radioactive decay. ... 05:56: You had the half-life-- so the average time for the decay of a polonium-212 nucleus. 06:09: All those individual probabilities combine to give you a 50% chance of decay after 0.3 microseconds.
	2016-06-29: Nuclear Physics Challenge 00:46: This drives the alpha decay of radioactive elements. 00:52: But don't literally take it, because it's one of the most radioactive elements known, and it decays as alpha particles tunnel out of its nucleus. 01:15: It has a half life of 0.3 micro-seconds, meaning half of any sample of polonium 212 will have decayed to lead in that time. 01:27: So after 0.3 micro-seconds, there's a 50% chance that a given polonium 212 nucleus will have decayed. 02:49: The alpha particle ejected in the decay of polonium 212 has a kinetic energy of 8.78 MEV. 01:15: It has a half life of 0.3 micro-seconds, meaning half of any sample of polonium 212 will have decayed to lead in that time. 01:27: So after 0.3 micro-seconds, there's a 50% chance that a given polonium 212 nucleus will have decayed. 00:52: But don't literally take it, because it's one of the most radioactive elements known, and it decays as alpha particles tunnel out of its nucleus.
	2016-06-15: The Strange Universe of Gravitational Lensing 10:24: An exponentially decaying part of its wave function is actually inside that wall.
	2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners! 01:42: And some are so hopelessly unstable that they decay into high energy light-- gamma rays-- before they ever reach a detector. 01:51: We only know they ever existed because the resulting gamma radiation has an energy corresponding to the mass of the decayed particle.
	2016-06-01: Is Quantum Tunneling Faster than Light? 04:41: When it's an alpha particle escaping a nucleus, this is one of the most important mechanisms for radioactive decay.
	2016-04-06: We Are Star Stuff 08:27: ... iron in your blood, was forged at the instant a star exploded, or are decay products from unstable elements formed in the ...
	2016-02-11: LIGO's First Detection of Gravitational Waves! 02:40: Now we've seen this slow orbital decay in binary neutron stars.
	2016-01-27: The Origin of Matter and Time 09:18: Kovacs asks, how can it be that if an elementary particle doesn't experience time, that they can still decay? 09:26: ... any particle that can decay, or even oscillate between states, like the electron's chirality flip, is ...
	2015-12-16: The Higgs Mechanism Explained 06:50: ... 2012, the LHC spotted the debris produced by the decay of an unknown particle, and those decay products are consistent with the ... 07:15: ... Higgs boson is hopelessly unstable, and it decays in around 10 to the power of minus 22 seconds, which makes it very ... 06:50: ... the debris produced by the decay of an unknown particle, and those decay products are consistent with the disintegration of the highly unstable Higgs ... 07:15: ... Higgs boson is hopelessly unstable, and it decays in around 10 to the power of minus 22 seconds, which makes it very ...
	2015-11-05: Why Haven't We Found Alien Life? 04:40: ... silicate crystals whose formation can be dated precisely by the ratio of decaying uranium versus lead decay product locked ...
	2015-10-22: Have Gravitational Waves Been Discovered?!? 04:22: ... a lot of this gravitational radiation, their obits will lose energy and decay, causing them to spiral in towards each ...
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 07:41: ... nanobots might disassembled the planet atom by atom-- and protons decay-- that maybe protons are unstable, and in quadrillions of years, ...

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