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2022-08-24: What Makes The Strong Force Strong?

  • 06:25: The further the electron gets from the nucleus, the more easily it can escape.

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

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

2022-06-15: Can Wormholes Solve The Black Hole Information Paradox?

  • 03:20: ... hole event horizon   before they can annihilate, one particle escapes and becomes real, while the other is swallowed.   But those ...
  • 04:44: ... might wonder if the Hawking radiation itself can serve as an escape route for that information.   But according to Hawking’s ...
  • 05:20: ... that must occur if Hawking radiation is our information escape route from the black hole. Any theory trying   to solve the ...
  • 12:40: ... technical calculation that tells us that   information can escape from the black hole. But what’s the real physical picture here? ...

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

  • 15:06: ... bosons of the   weak interaction. The fourth boson manages to escape  unscathed and massless, becoming the photon   that we know and ...

2022-02-16: Is The Wave Function The Building Block of Reality?

  • 14:42: Last time we tackled a question of utmost gravity. Literally. How does gravity itself escape the inescapable gravity of a black hole.
  • 16:48: ... surface around the black hole below which no sub-lightspeed object can escape. ...
  • 17:28: ... by escape I mean reach YOU at your “infinite distance”. And it’s the surface from ...

2022-01-27: How Does Gravity Escape A Black Hole?

  • 00:10: Nothing can escape from within the event horizon unless it can travel faster than light.
  • 00:27: How does gravity escape a black hole?
  • 06:03: So can gravity escape from a “real” black hole of quantum gravity?
  • 06:42: If gravity is really communicated by a particle, how does that particle escape the event horizon?
  • 11:45: By that definition the mass of a black hole is everywhere - so it’s not surprising that it can escape the horizon.

2022-01-12: How To Simulate The Universe With DFT

  • 15:14: The minimum velocity it could have on reaching the Earth is the solar system’s escape velocity at Earth’s orbit, or around 42 km/s.
  • 15:49: Either way, it’ll still have solar system escape velocity after the passage through the earth and we would never see it again.
  • 19:44: And actually there’s a way to shed your excess energy, and you have an escape route when the Reapers arrive.

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

  • 00:02: ... the other regions become uh diffuse enough that all of that light escapes okay and so they radiate brightly as the light starts to escape and ...

2021-11-17: Are Black Holes Actually Fuzzballs?

  • 00:39: ... - which is surrounded by a surface from which even light can’t escape - the event ...
  • 10:50: Light trying to escape would still be massively redshifted - sapped of energy by the gravitational field - rendering the object effectively black.
  • 12:10: The event horizon is just the pair of equidistant points on the line inside of which escape is impossible.

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

  • 02:22: In radioactive decay, particles that should never have enough energy to escape the nucleus are found to leak out.
  • 02:31: The key to the escape is quantum uncertainty.

2021-09-15: Neutron Stars: The Most Extreme Objects in the Universe

  • 13:06: ... horizon and we’ll be   stuck inside an actual black hole. Escape will become even more impossible than it already is.   I ...

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

  • 02:23: ... still imprinted with a wealth of information about the monster that it escaped. ...
  • 11:25: So it looks like we’re seeing an expanding vortex of stuff that just narrowly escaped being sucked into the black hogle.

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

  • 02:44: One gets trapped, allowing the other to escape.

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

  • 01:13: As we’ve discussed many times before, black holes are regions of gravitational field so intense that not even light can escape.

2021-03-09: How Does Gravity Affect Light?

  • 02:36: I dunno, to escape giant alien spiders or something.
  • 04:37: ... is so strong that clocks stop and the frequency of photons trying to escape is brought to ...

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

  • 03:51: A photon trying to escape from inside the Sun encounters a lot of obstacles.
  • 05:07: So any photons trying to escape the Sun that happen to have one of these particular energies are going to get sucked up on its way out.

2020-08-17: How Stars Destroy Each Other

  • 11:14: ... star - but if that core is above a certain mass it shrinks so that the escape velocity at its surface is greater than the speed of ...

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

  • 00:00: ... subject is that you have to say okay well why is it that we can't escape the gravitational pull of the past failures why are we still talking ...

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

  • 05:34: And much more difficult to escape the neutron star - the escape velocity at the surface is up to half the speed of light.
  • 05:42: ... stars are on the verge of being black holes, which by definition have an escape velocity at the event horizon equal to the speed of ...
  • 05:51: If only you could cram a little more matter into the neutron star, the escape velocity would increase and it would become a black hole.
  • 06:36: So more mass in a neutron star means higher surface gravity means higher escape velocity.

2020-06-22: Building Black Holes in a Lab

  • 05:25: ... virtual particles appear near the event horizon and are separated - one escapes and one falls in, somehow converting to negative energy and so ...
  • 10:13: ... as with real black holes, some atoms do escape as Hawking radiation. Here you can measure not just the existence, but ...

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

  • 03:34: ... a long time it was believed that viruses evolved as escapees from DNA-based cells, but more and more virologists think that viruses ...

2020-05-18: Mapping the Multiverse

  • 01:01: ... space that the gravitational field becomes too strong for even light to escape. ...

2020-04-28: Space Time Livestream: Ask Matt Anything

  • 00:00: ... Simone loves to watch the pigeons out the windows landed on the fire escape which is also a huge fan of treats well no she's too distracted right ...

2020-03-31: What’s On The Other Side Of A Black Hole?

  • 04:14: ... the event horizon, even a light-speed path has only a narrow window of escape. Once inside the event horizon, no such window ...
  • 08:22: ... - that’s light from anything that fell in before you. It’s trying to escape and will ultimately fail, dragged down by the cascading fabric of ...

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

  • 03:54: ... thing deep beneath the event horizon is rotating. But if nothing can escape the event horizon, how can that internal rotation influence the ...
  • 09:17: ... the event horizon while the other is ejected from the ergosphere and escapes. In fact it escapes with more kinetic energy than it had coming in - up ...

2019-08-19: What Happened Before the Big Bang?

  • 01:18: See, if we accept that inflation happened at all, it's hard to escape the conclusion that it never actually stopped.

2019-07-25: Deciphering The Vast Scale of the Universe

  • 02:05: ... fuzzy blobs were zipping away from us so quickly that they would surely escape the Milky Way’s gravitational ...

2019-07-15: The Quantum Internet

  • 13:26: ... the system has much higher temperature tolerance even if the coolant escapes - natural air circulation should keep it sub-meltdown ...

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

  • 02:49: ... thermal reactor due to a cooling failure in Three Mile Island the water escaped a jammed hatch in Chernobyl water boiled increasing the neutron count ...

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

  • 06:15: Much of the quasars once ultraviolet light was sucked up before it escaped the early universe.

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

  • 02:47: ... converted neutrons back to protons also provides the mechanism for their escape the beta decay releases both electrons and neutrinos in fact a wind of ...

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

  • 05:58: The event horizon itself is the point where even outward-pointing light can’t escape the black hole.
  • 06:36: We only see light that escapes directly towards us, so the photon sphere looks like a photon ring.

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

  • 13:51: Electrons escape their orbits by quantum tunneling, and protons themselves may eventually decay.

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

  • 00:37: ... life but could hitchhiking microbes have survived that ejection to escape Earth's gravitational field a chunk of impact debris has to be kicked to ...

2018-11-14: Supersymmetric Particle Found?

  • 15:36: Those dimensions are tiny in extent and they're coiled on themselves so there is nowhere for gravity to escape into.

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

  • 11:11: ... separated by the black hole event horizon, allowing one of the pair to escape to beautiful freedom and ...

2018-09-05: The Black Hole Entropy Enigma

  • 02:55: From there it could be imprinted on the outgoing Hawking radiation, allowing the information to escape back into the universe.
  • 06:09: So you know how nothing can escape black holes, ignoring Hawking radiation for the moment.

2018-08-01: How Close To The Sun Can Humanity Get?

  • 06:33: To escape Earth's orbit in the outward direction, you first, need to escape Earth's gravitational pull and then, accelerate to achieve a larger orbit.
  • 06:41: ... move closer to the sun, you need to first, escape the Earth and then, lose speed, which can be even trickier than gaining ...

2018-06-20: The Black Hole Information Paradox

  • 00:40: And we now know that this mass can escape.
  • 10:20: But to enter the game, Hawking had to concede the old bet and admit that information does escape black holes.
  • 13:41: ... the electromagnetic field is communicated by photons and photons can't escape the black ...
  • 14:35: ... this picture, virtual particles can escape a black hole to communicate the influence of the charge within, but it's ...

2018-06-13: What Survives Inside A Black Hole?

  • 00:40: Nothing can travel faster than light, and so nothing can escape from below the event horizon-- not matter, not light, not even information.
  • 02:20: Nothing beneath the event horizon can influence the exterior universe because no signal can escape the event horizon to carry that influence.

2018-03-15: Hawking Radiation

  • 02:03: ... pair will be swallowed by the event horizon, leaving the other free to escape and taking its stolen energy with ...
  • 06:55: They are nudged off their narrow escape path and so are lost behind the forming event horizon.

2018-02-21: The Death of the Sun

  • 02:51: That burning shell is so thin that radiation escapes outwards without providing pressure to resist collapse.
  • 06:25: ... hold on us, or the sun may just expand too quickly and too far for us to escape. ...
  • 07:28: ... the Earth-- perhaps it just managed to escape the expanding sun and is now a lonely desolate world orbiting out in the ...

2017-12-20: Extinction by Gamma-Ray Burst

  • 00:53: Hopefully, our super advanced and probably not-quite-human descendants will be able to escape those by traveling to other star systems.

2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor

  • 04:00: Another way to think of this is in terms of escape velocity.
  • 04:03: That's the velocity an object would need to have to escape a gravitational field.
  • 04:18: The escape velocity at that closest approach was a little over 80 kilometers per second.
  • 04:24: That means Oumuamua has enough speed to climb out of the sun's gravitational well and escape back to interstellar space.
  • 05:47: ... star would have been over 100 kilometers per second, higher than the escape velocity at the distance of closest approach to that ...

2017-10-25: The Missing Mass Mystery

  • 12:21: ... if virtual particles control faster than the speed of light, can't they escape the event horizon of black holes via Hawking ...

2017-10-11: Absolute Cold

  • 01:37: You get more heat causes electrons than any gas to escape the bonds of their atoms, resulting in the less known plasma state.

2017-08-30: White Holes

  • 01:31: ... boundary called the event horizon, from inside of which nothing can ever escape. ...
  • 05:39: ... traveling at that 45 degree angle takes infinite time to escape the event horizon, and the region beyond that line represents the ...

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

  • 06:39: Those photons quickly escape the cloud, taking energy with them, and helping to cool things down.

2017-04-19: The Oh My God Particle

  • 06:24: It can trap particles and accelerate them until they're energetic enough to escape the shock.

2017-03-29: How Time Becomes Space Inside a Black Hole

  • 07:12: That last tiny sliver is a narrowing window directly above that you could escape to at close to the speed of light.
  • 07:20: Meanwhile our past light cone now encompasses light that has been struggling to escape from just above the event horizon since the distant past.

2017-01-11: The EM Drive: Fact or Fantasy?

  • 03:01: ... those photons actually escape the cavity, then any momentum exchange between the cavity and radiation ...
  • 03:12: And if photons do escape, then you've just built a photon thruster.
  • 07:49: Or if they escaped, they'd be a propellant, and momentum would be exchanged with no more efficiency than a photon thruster.

2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer

  • 00:16: ... fact, the second part of this episode will be the answer to our Escape the Kugelblitz Challenge, which is highly theoretical and in fact, a ...

2016-12-21: Have They Seen Us?

  • 15:29: You can escape a black hole by traveling faster than the speed of light.
  • 15:59: Some people complained about my use of the expression "escape velocity greater than the speed of light" at the beginning of the episode.
  • 16:17: ... derision it receives in nerd circles, it's accepted to talk about the escape velocity at the surface of the Earth because we're used to Newtonian ...
  • 16:39: That's the velocity you need to escape.
  • 16:43: The reason that people poo-poo the expression "escape velocity" is that it reminds us of a strange coincidence.
  • 16:49: ... if you use Newtonian gravity to calculate the distance at which the escape velocity reaches the speed of ...
  • 17:06: But the concept of escape velocity at the event horizon is still as meaningful as it is from the surface of the Earth.

2016-12-08: What Happens at the Event Horizon?

  • 00:29: Black holes, objects with densities so high that there's this region, the event horizon, where the escape velocity reaches the speed of light.
  • 00:38: ... that falls below the event horizon can never escape and is lost to the universe forever while we see falling objects freeze ...
  • 03:57: That makes it difficult to figure out what parts of the past and future universe the monkey can witness or escape to.
  • 06:52: The only way to escape back to the outside universe would be to widen your light cone by traveling faster than light.
  • 07:53: Well, it could still escape.

2016-09-29: Life on Europa?

  • 12:13: ... says there is a way to escape the inference of superluminal speeds and spooky action at a distance, ...

2016-06-29: Nuclear Physics Challenge

  • 01:34: The challenge for today is for you to figure out the tunneling probability for an alpha particle to escape from a polonium 212 nucleus.

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

  • 08:46: ... outspiraling light escapes the photon sphere, it joins with severely lensed light from any ...
  • 10:41: To escape, it needs to tunnel all the way to the other side, where it finds itself in a lower energy state.

2016-04-20: Why the Universe Needs Dark Energy

  • 04:56: ... universe with exactly the right density, that's expanding at exactly its escape velocity, one that will slow to a stop over infinite time, should be ...

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

  • 02:45: ... I throw it at 11 kilometers per second, which is the escape velocity on Earth's surface, then, by the time it almost stops moving, ...
  • 02:58: Now this escape velocity comes right out of Newton's universal law of gravitation, which itself can be derived from the Einstein equations.
  • 03:07: The mathematical step from Newton's gravity to escape velocity comes from thinking about energy.
  • 03:27: There's a minimum kinetic energy that the apple needs in order to escape the energy-sucking gravitational-potential well of the Earth.
  • 03:36: That minimum kinetic energy tells you the escape velocity.
  • 03:40: ... analogy-- and, remember, ignoring dark energy-- the universe also has an escape velocity that lets distant galaxies escape each other's gravitational ...
  • 04:05: How do we calculate the escape velocity for the whole universe?
  • 06:22: Essentially, that's if the expansion is exactly equal to the escape velocity.

2015-08-19: Do Events Inside Black Holes Happen?

  • 06:54: Misconception two-- black holes are black because not even light can escape their gravitational pull.
  • 07:03: ... on the surface of a planet or a star needs a minimum speed called the escape velocity in order to get really far and not turn back as it's pulled by ...
  • 07:15: If a planet's radius equals the Schwarzschild radius of the equivalent-mass black hole, it turns out that the escape velocity is the speed of light.

2015-05-27: Habitable Exoplanets Debunked!

  • 08:02: Hansen from It's OK To Be Smart asked, if my mirrored box had a tiny hole in it so some light could escape, would its mass go down?

2015-05-20: The Real Meaning of E=mc²

  • 03:45: Once that energy escapes, you're not weighing it anymore.
  • 04:53: ... an exactly equal amount of extra light energy that we're not allowing to escape this ...

2015-04-08: Could You Fart Your Way to the Moon?

  • 01:35: ... strike, and the particles push the rocket forward as they ricochet and escape out the open ...
  • 02:48: In truth, even starting out from low Earth order, you'd be short of Earth's escape velocity by a factor of about a billion.
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