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2022-12-14: How Can Matter Be BOTH Liquid AND Gas?

  • 03:45: To start with, both are fluids - they flow.
  • 08:27: At that point, microscopic droplets of remaining liquid are free to flow and swirl through the gas phase to diffuse.
  • 08:59: The viscosity of supercritical fluids is extremely low, so they flows and diffuse more like a gas than a liquid.
  • 10:15: But it still moves like a gas, so it can flow and diffuse into places that liquids can’t access.
  • 12:33: ... oxidation, but when you want to avoid actual wetness, or you need it to flow and diffuse like a ...

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

  • 00:12: But the only elementary particle actually flowing in the circuit are the negatively charged electrons.
  • 00:19: And yet those flowing positive charges are there, in the form of a particle you may never have heard of.
  • 02:13: It looks like the hole moves around, and under a voltage the hole moves in the opposite direction to the flow of electrons.
  • 03:21: This is an n-type semiconductor - n because the flowing charge is negative.
  • 03:32: ... shuffle to fill the gaps in the underfilled valence shells - so we have flowing positively charged electron holes and a p-type ...
  • 03:48: ... end up with a region where all valence shells are filled so charge can’t flow. ...
  • 04:00: ... a voltage in one direction and the holes and electrons flow away from this junction, expanding the non-conductive region and ...
  • 04:09: ... junction, causing it to narrow and electrons hop across, enabling the flow of ...
  • 10:03: ... in both directions with the atoms, which prevents a smooth, streamline flow You might think that cooling down the metal alone would be enough to ...
  • 12:54: In fact at very low temperatures all of the pairs in an enormous network of flowing electrons can all occupy the lowest energy state.

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 10:07: ... years time. And improved positioning and observing strategies will flow down the string of ...

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

  • 11:26: ... stream of amazing images and even more amazing science that’s sure to flow in from Earth’s Lagrange 2 point over the next years as the James Webb ...

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

  • 13:36: Imagine VPN as an encrypted tunnel for online traffic to flow.

2022-08-03: What Happens Inside a Proton?

  • 15:29: ... around a kilometer. But on larger   scales, it’s hot enough to flow like a liquid and move around entire tectonic plates.   ...

2022-07-27: How Many States Of Matter Are There?

  • 09:30: ... grain of sand is a solid, but when you make air flow through sand you can change how those grains of sand interact with each ...

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

  • 02:25: ... opposite signs to the charge.  He imagined an electric fluid that flowed  from one to the other, so that in one you   have an excess of ...
  • 10:41: ... That universe works just like our universe if you reversed the flow of ...
  • 11:52: ... that we need to figure out is how the aliens define   the flow of time. Do they define the future as an increasing progression of ...

2022-05-25: The Evolution of the Modern Milky Way Galaxy

  • 18:41: ... general relativity in which we can say that  space is flowing inwards in a gravitational   field. You may have heard me say ...

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

  • 03:40: ... and hotter and eventually ignited in nuclear  fusion. The outward flow of fusion-generated   energy supports the Sun against ...

2022-05-04: Space DOES NOT Expand Everywhere

  • 01:24: ... the further distant the faster the recession. We call this the Hubble flow, after Edwin Hubble, the guy who first measured the rate of ...
  • 01:59: ... Hubble flow could be interpreted as everything moving THROUGH space, but there’s a ...

2022-03-30: Could The Universe Be Inside A Black Hole?

  • 01:07: We can think of the event horizon as the surface where the flow of space itself is like a river moving at the speed of light.
  • 01:13: Nothing can swim against that flow.
  • 06:24: Space flows at the speed of light across the event horizon from within.

2022-03-23: Where Is The Center of The Universe?

  • 07:33: Draw a line in that direction and at the same time reverse the flow of time to see what it intersects.

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

  • 00:03: ... as as literally moving away from us um versus being trapped in the flow of space because the two are completely distinguishable on the ...

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

  • 04:24: ... gravity: instead of a stretching spacetime, we can think about space as flowing towards the massive ...
  • 04:46: A close analogy to this picture of gravity is a river flowing towards a waterfall.
  • 05:24: Gravity works like the rubber sheet or the flowing river.

2022-01-19: How To Build The Universe in a Computer

  • 07:46: But they also work for another really important  astrophysical situation - flowing gas.
  • 07:57: ... gas is still everywhere - it flows into galaxies from beyond, where it rides the disk, fragments and ...
  • 08:17: Now we call these hydrodynamic simulations - they simulate the flow of gas using the equations of fluid dynamics.
  • 08:45: ... astrophysics, SPH codes are used to simulate  the flows of gas in galaxies and around quasars, used to simulate star and planet ...
  • 09:05: ... often use an amalgam of these methods - for example SPH for large scale flows and particle-particle N-body for small-scale ...

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

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

2021-12-20: What Happens If A Black Hole Hits Earth?

  • 07:05: ... of a micro black hole is a very narrow choke-point for matter trying to flow in. Its Eddington limit is very low. For an asteroid-mass black hole at ...

2021-11-02: Is ACTION The Most Fundamental Property in Physics?

  • 14:15: ... PBS. Imagine VPN as a secure, encrypted tunnel for online traffic to flow. Nobody can see through the tunnel and get their hands on your internet ...

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

  • 02:00: ... field then becomes a particle accelerator, with electron currents flowing one way and   positron currents flowing the other way- ...

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

  • 04:51: Pockets of gas within this flow are somehow shielded and so that gas can cool down a bit.
  • 06:56: And two: it’s being blasted out, riding the flow of radiation from the inner accretion disk.
  • 10:12: ... also have winds of matter flowing at incredible speeds - but this close to the black hole only the ...

2021-07-21: How Magnetism Shapes The Universe

  • 03:53: Here the field is generated by electrical currents flowing in the searing plasma near the Sun’s surface.
  • 03:59: The Earth’s solid inner core and mantle regulate the flow in its liquid outer core, resulting in a clean dipole field.
  • 08:58: ... turbulent, they arrange themselves into a series of self-supporting flows. ...
  • 09:21: ... rotation in the disk which can lead to coriolis-induced helical flows, and those flows can also be produced by supernova ...
  • 10:27: But the galactic magnetic field constrains that flow, funneling some of it into vast galactic fountains erupting from the poles.
  • 12:09: Thick flows of gas can be catapulted through the surrounding galaxy in powerful jets.

2021-06-23: How Quantum Entanglement Creates Entropy

  • 02:48: ... - then it will tend to become mixed, and   we can harness that flow. Ludwig Boltzmann recast entropy in terms of the number of ...

2021-04-21: The NEW Warp Drive Possibilities

  • 03:01: For example inside black holes where we can think of space as flowing downwards faster than light.

2021-03-16: The NEW Crisis in Cosmology

  • 13:30: ... in which we explored the connection between gravity, light, and the flow of ...

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

  • 01:38: ... as the force of gravity is mostly due to the way mass warps the flow of ...
  • 01:47: But the photon doesn’t experience the flow of time - it doesn’t even have any mass.
  • 06:00: ... with a physical explanation for the prediction - the difference in the flow of time changes the frequency of outgoing ...
  • 12:32: Light is a wave and a particle; time slows or space flows in gravitational fields.

2021-02-24: Does Time Cause Gravity?

  • 01:17: But I never explained WHY or HOW gravity causes the flow of time to slow down.
  • 01:28: Gravity does NOT warp the flow of time.
  • 02:58: ... through time according to those velocities, we have this sense of time flowing in a gradient - faster streams distant from the Earth, slower streams ...
  • 03:08: Kind of like how water in the center of a stream flows more quickly than the edge, where the shallower stream drags on that flow.
  • 03:16: It’s almost like Earth’s mass creates a drag on the flow of time around it.
  • 04:56: And it’s always rotated in the direction of decreasing flow - which in a gravitational field is downwards.
  • 07:11: ... at multiple places at once, and so experiences the gradient of time flow. ...
  • 08:08: ... to shift our perspective in a couple of mind-bendy ways to see how the flow of time determines the path of even timeless ...

2021-02-10: How Does Gravity Warp the Flow of Time?

  • 00:11: But that tiny difference in flow of time may be what keeps you stuck to this planet at all.
  • 09:25: ... kind of blows me away that you can calculate the difference of the flow of time between an inertial and accelerating frame using pure special ...
  • 09:53: ... twin paradox, gravitational time dilation gives the right relative time flows if you consider the traveling twin to be in a gravitational well with a ...

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

  • 04:48: Once its nuclear fuel supply runs out, there would be no outward flow of energy to resist the gravitational crush.
  • 14:28: If correlations grew in the opposite direction - the wave flowed backwards, our definition of future and past would flip.
  • 14:43: ... quote: even if time did flow backwards, from future to past, in each time step we would not remember ...

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

  • 00:10: So why do we seem to be stuck in this inexorable flow towards the future? It's time to begin our journey towards really understanding time.
  • 00:24: ... laws don’t distinguish between the future and the past. Reverse the flow of time and their equations work exactly the same to describe a universe ...
  • 01:58: ... where we have 2-dimensions of space and one dimension of time, with time flowing ...
  • 02:31: ... change over time. But if we flip this diagram on its head - reverse the flow of time, it still looks like two electrons bouncing off each other. The ...
  • 02:53: ... by the laws of physics. And those laws don’t even require time to “flow” - it’s just another dimension like ...
  • 09:39: ... need to explain one thing. How is the thermodynamic arrow of time - the flow of time defined by increasing entropy -connected to our sense of the ...

2020-10-20: Is The Future Predetermined By Quantum Mechanics?

  • 15:15: Rather consciousness surely requires dynamical processes, a flow of information.

2020-10-13: Do the Past and Future Exist?

  • 03:17: Time is just a dimension like space, and we only observe a flow of time if we play the slices in sequence like a flip-book.

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

  • 07:18: ... Flowing plasma and magnetic fields may stretch and break necklaces, which could ...
  • 08:28: It’s possible to use energy as it flows between different states in this process, like putting a water wheel in a flowing river.
  • 08:35: For example, life uses the energy flowing from the high energy-density of the Sun to the lower energy density of the Earth.
  • 09:06: Energy flows from the fusion engine in the core to the surface.
  • 09:09: It’s conceivable that a lifeform could harness that flow.

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

  • 14:28: ... shouldn’t there be a thin sliver of space in between that is not flowing towards either ...
  • 14:44: The key point is that space doesn’t have to flow directly towards the singularity.
  • 14:59: In the case of the merging black holes, you can think of space as more flowing towards the center of mass - although it’s not quite that simple.
  • 15:28: ... flow of space anywhere on the event horizon has to be exactly perpendicular ...
  • 15:40: In principle there should be a point right at the center where there is no flow - if you were a point-like particle you could just hang there.
  • 15:47: But everywhere else - including above and below that point the space is still flowing inwards.

2020-08-17: How Stars Destroy Each Other

  • 04:31: If the white dwarf has a strong magnetic field, the flow of gas from its companion is channeled by that field.
  • 05:58: And like cataclysmic variables, the flow is uneven so the X-rays fluctuate.
  • 11:32: Well, below that event horizon, we can think of space flowing downwards faster than the speed of light.
  • 13:56: ... the event horizon - the surface below which there’s a faster-than-light flow of ...

2020-06-30: Dissolving an Event Horizon

  • 00:44: ... horizon: the surface around the central singularity where the inward flow of space reaches the speed of light, and time freezes from the ...
  • 02:45: With nothing to counter the inward flow of space, an event horizon is inevitable.
  • 03:18: The result is that we get this region around the singularity where the faster-than-light inward flow of space is halted.
  • 03:46: There’s no longer a region where the inward flow of space exceeds light speed.

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

  • 03:26: ... in a form that is a close analogy to the equations governing the flow of spacetime - the equations of general relativity. And a vortex ...
  • 04:45: ... setup uses a tank in which a current of water flows over a sloped obstacle. As the depth of water decreases, the current ...
  • 04:55: At some point the flow is faster than the waves - and that’s your analog event horizon.
  • 05:01: ... the flow is in the opposite direction to the waves this is actually an analog ...
  • 08:04: ... That’s the region around the event horizon where the circular flow of space becomes irresistible. It turns out that water vortices also ...
  • 09:19: ... gas in a BEC state. Using a laser, it’s possible to effectively create a flow within the ...

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

  • 03:33: And there’s the key point: light does not experience the flow of time.

2020-05-18: Mapping the Multiverse

  • 01:47: It describes the way spacetime warps and flows in the vicinity of a spinning mass.
  • 02:16: Well, in a Kerr black hole that rotation results in an outward pressure that partially counteracts the inward flow due to gravity.
  • 03:11: Time flows up - for the most part - and one dimension of space is left or right.
  • 04:06: But now as we fall the outward pressure due to the black hole’s rotation starts to win against that inward flow.
  • 04:16: In fact the flow eventually slows to less than the speed of light.
  • 05:00: It’s surrounded by a second ergosphere, where again the rotational flow of space exceeds light speed.
  • 06:02: ... balls from space they’ll trace the downward cascade of space - and that flow would be pretty spherically ...
  • 09:03: That outgoing flow continues above the inner horizon, and will eventually eject you past the outer horizon.
  • 11:38: ... but they’re causally disconnected, the difference being that time flows forward if you go in one direction and backwards if the ...
  • 11:50: So you have this messed up situation where the direction of the flow of time actually clashes at the inner horizon.
  • 12:06: ... there’s any stuff at all in the black hole then the forward flow of time carries a current of positive energy, while the backwards ...
  • 13:26: That resists the inward flow just like rotation does in a Kerr black hole.

2020-05-11: How Luminiferous Aether Led to Relativity

  • 02:33: ... to the space between the celestial bodies. He imagined the aether as flowing - moving in vortices. These flows carried the celestial bodies, for ...
  • 03:25: ... down only, tugging on neighboring segments so that a sinusoidal pattern flows forwards, while the segments themselves just oscillate in place. In ...
  • 12:25: ... Descartes seems prescient: empty space is not really empty. Its flowing fabric is the source of the gravitational field, and its full of quantum ...

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

  • 00:00: ... dry and Einstein actually says that he's not going to add unnecessary flower flourish or poetry to it because he wants it to be principally ...

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

  • 03:43: ... some numbers, based on pure speculation - to quote: “There has mayhap flown past a series of millions of years and centuries, etc. etc. ... Creation ...

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

  • 07:57: ... towards the central singularity - it’s the old radial direction, but now flows only in one direction - to your crushing demise. These lines are the old ...

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

  • 00:21: ... fabric of space cascades downwards at the speed of light, and where the flow of time halts from the perspective of the outside universe. It predicts ...
  • 05:14: ... flow of space around a rotating black hole is known as frame-dragging. We see ...
  • 07:50: ... moves downwards faster than light. In the math, that faster-than-light flow of space is represented in a particularly weird way - space and time ...
  • 10:51: ... process. In this case you have a magnetic field produced by the flow of material around the black hole in an accretion disk. The flow of ...

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

  • 00:04: ... episode of space time is brought to you from the information flowing through an impossibly complex network of quantum entanglement, that just ...

2020-02-11: Are Axions Dark Matter?

  • 11:56: ... PBS. Imagine VPN as a secure, encrypted tunnel for online traffic to flow. Nobody can see through the tunnel and get their hands on your internet ...

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

  • 15:08: ... photon to deflect the electron - in other words, the direction of the flow of time is irrelevant from the perspective of the virtual photon - what ...

2019-11-04: Why We Might Be Alone in the Universe

  • 06:11: Above Earth’s core is a solid mantle which still flows due to its heat.

2019-10-21: Is Time Travel Impossible?

  • 04:14: ... speed of light or drop it into a deep gravity well – its rate of time flow will slow relative to the other end of the ...

2019-09-03: Is Earth's Magnetic Field Reversing?

  • 02:02: We can track the direction of Earth’s magnetic field in sedimentary layers and in old volcanic flows.
  • 03:15: Alternatively, flows of many charged particles like electrons – so electrical currents - can produce magnetic fields.
  • 04:55: As the inner core grows it releases non-iron impurities that flow upwards, joining convection streams.
  • 05:03: These flows are then twisted into helixes by the coriolis force – the same effect that produces hurricanes on Earth’s surface.
  • 06:40: Those flows grab hold of our toroidal magnetic field and twist it up further - into many little loops.
  • 07:27: ... can produce such a field – the Earth, but also the Sun with its flowing hydrogen plasma, or the liquid metallic hydrogen in Jupiter and Saturn’s ...
  • 08:18: The strength of the field across the surface also changes, and all of these shifts are due to changing flows within the outer core.
  • 08:37: ... direction of small magnetic loops generated by these helical convection flows. ...
  • 09:36: It may be that some event triggers a disruption in the flows within the outer core.

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

  • 07:32: ... mapping of the universe – galaxies assembled into many vast filaments, flowing together on rivers of dark matter to form the cosmic web, of which ...

2019-07-15: The Quantum Internet

  • 13:16: It's cool because it's passively cooled by gas flow - for example, helium.

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

  • 02:49: ... The moderator is a lattice of graphite channels through which the fluid flows Graphite is particularly great because it slows neutrons without ...

2019-06-17: How Black Holes Kill Galaxies

  • 05:24: ... giant galaxies should've kept forming stars Giant reservoirs of gas flowed into those clusters from the outside Universe In our simulations of the ...

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

  • 08:55: ... simulation that weaves in all of the physics of fluid flow and magnetic fields, in this case with the addition of the warped ...

2019-04-03: The Edge of an Infinite Universe

  • 15:45: ... than light at the event horizon, that should counter the light-speed flow of space into the event horizon, causing the event horizon to shrink and ...

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

  • 01:27: Bhāskara's wheel, named after the Indian mathematician, was embedded with tubes of mercury that would flow from back and forth as the wheel turned.
  • 03:20: All machines work by riding this flow of energy as it redistributes itself.
  • 05:01: ... a piston chamber that will provide the maximum possible energy as heat flows between reservoirs of different ...

2019-02-20: Secrets of the Cosmic Microwave Background

  • 01:47: ... a simplistic picture A quick review In the very beginning Dark matter flowed towards tiny regions of increased ...
  • 02:05: ... places the over-densities were smaller The density wave had time to flow in reverberate out and then get captured by the gravitational field once ...

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

  • 04:19: In particular, the dark matter flowed inwards towards this density peak.
  • 06:46: ... the expanding wave froze, both dark matter and baryons flowed together and consolidated the new structure. Once more in the ...

2018-12-12: Quantum Physics in a Mirror Universe

  • 00:02: ... to negative and vice-versa and a reversal in the direction of the flow of time will also restore a system to its original state this is CPT ...

2018-11-14: Supersymmetric Particle Found?

  • 05:32: Lower energy neutrinos can flow right through the Earth as though it isn't there.

2018-08-30: Is There Life on Mars?

  • 04:05: ... That's Italian for "channels," presumably implying naturally formed flows of ...
  • 05:55: This evidence for ancient flowing water wasn't definitive at the time.

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

  • 03:31: ... of the Parker Solar Probe-- as stated by NASA-- is to trace the flow of energy and understand the heating of the solar ...
  • 04:00: It will also measure the outward flow of the magnetic field through the pointing flux, as well as the plasma density and electron temperature.
  • 04:38: It will follow the flow of energy from the solar corona into the accelerating solar wind and connect the solar wind to its source.

2018-07-25: Reversing Entropy with Maxwell's Demon

  • 03:20: The particles would quickly flow to fill the available space, and you could extract energy from that flow.

2018-07-18: The Misunderstood Nature of Entropy

  • 01:54: Heat engines, which in Carnot's day, were the new-fangled steam engines, worked by turning the flow of heat energy into mechanical energy.
  • 02:02: For heat to flow, you need two reservoirs of different temperature.
  • 02:20: However, an inefficient engine will slowly deplete the difference in temperature, reducing the heat flow, and the engine winds down.
  • 03:35: ... understanding of entropy is in terms of flowing heat, and it came from the days when many, including Carnot himself, ...
  • 09:34: Heat must flow between your system and the outside universe in a way that increases the entropy of the universe as a whole.

2018-07-04: Will A New Neutrino Change The Standard Model?

  • 06:41: ... order to evolve that way, neutrinos must experience the flow of time, which means they can't be moving at the speed of light, which ...

2018-06-20: The Black Hole Information Paradox

  • 03:02: That distortion looks like particles flowing away from the black hole.

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

  • 09:19: ... star or a whirlpool of gas, it will either add or subtract from this flow of space above the event ...

2018-05-09: How Gaia Changed Astronomy Forever

  • 07:11: These dynamically connected flows of stars, once bound together as a globular clusters or dwarf galaxies.
  • 07:17: It's been hypothesized that disruptions in these flows are due to clumps of dark matter, so-called sub halos.

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

  • 01:15: For life to stave off rising entropy and decay, energy must flow.
  • 03:20: Energy is transported in giant convection flows rising to the surface and sinking again.
  • 03:40: Rivers of plasma flow from the core to the surface, carrying both energy and the helium produced in the fusion reactions.

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

  • 04:58: When two systems with very different energy densities come into contact, energy must flow.
  • 05:03: Life feeds on that flow.
  • 06:29: ... energy flows from hot to cold, seeking a uniform temperature, but energy is also ...
  • 07:11: But when our energy source is flowing into a much larger reservoir, why, the ocean, for example, then equilibrium is never reached.
  • 09:07: Consider a perfectly streamlined or laminar flow of some fluid.
  • 09:11: This organized flow is disrupted by introducing turbulence.
  • 09:15: ... laminar flow has a lower entropy than the turbulent flow because there are fewer ways ...
  • 09:32: Waves and vortices have their own complex and regular structures, but they ultimately serve to dissipate the flow.
  • 09:39: ... but the source of that local incidence of low entropy is the streamline flow that it formed ...
  • 09:49: And those turbulent eddies ultimately serve to increase the entropy of the greater flow.

2018-04-04: The Unruh Effect

  • 05:20: The Rindler horizon flows at a fixed distance behind a constantly accelerating observer.

2018-03-07: Should Space be Privatized?

  • 11:12: That means new hydrogen flows down to the core, while the helium produced in core fusion is mixed through the star.

2018-02-21: The Death of the Sun

  • 01:31: ... life, I mean the period of core hydrogen fusion, when the steady flow of energy from the core provides consistent support against the ...
  • 02:22: ... core's last gasp, it'll be less than 20 million K. So with no outward flow of energy to fight against gravity, that core begins to collapse, ...
  • 03:09: That incredible outward flow energy does counteract gravity for the outer layers of the sun, and those layers expand.

2018-02-14: What is Energy?

  • 07:42: ... example, Bernoulli's equation predicts the flow of fluids by demanding the conservation of the kinetic and potential ...

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

  • 01:09: ... giant ball of fiery hydrogen due to a delicate balance between the outer flow of energy produced by fusion in the core and the gravitational crush of ...

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

  • 00:38: ... described the balance between the gravitational crush and the outward flow of energy from the fusion reactions in the ...
  • 00:49: ... things like the density and temperature of the core, the way energy flows to the surface, and even the life span of ...
  • 13:05: ... them to higher energies, and preferentially in the direction of the flow. ...

2017-11-02: The Vacuum Catastrophe

  • 10:36: That energy comes from shocks that develop as the material flows in the gravitational field of surrounding clusters.

2017-10-25: The Missing Mass Mystery

  • 05:30: Rivers and sheets of dark matter flow into giant dark matter halos, dragging baryonic matter with them.
  • 08:20: We talked about the kinetic SZ effect in our episode on dark flow.
  • 10:22: ... our universe is spread out in the vastness of intergalactic space, still flowing with rivers of dark matter into the galaxy ...

2017-10-11: Absolute Cold

  • 03:13: This means that they flow with no resistance whatsoever.
  • 03:25: They flow unrestricted through the material making it a superconductor.

2017-09-20: The Future of Space Telescopes

  • 03:16: ... you'll have a flower-like shape, whose cleverly calculated petal geometry is designed to diffract ...
  • 03:33: ... fold into a very compact bud for launch, and then open up like an actual flower once in space, a bit like the James Webb Space ...

2017-08-30: White Holes

  • 01:31: ... black hole is defined as a region of inward flowing space time with a one way boundary called the event horizon, from inside ...
  • 01:41: That makes a white hole a region of outward flowing space time.
  • 05:54: The once vertical contours of space are now time-like and flow inexorably towards the future singularity.
  • 06:32: ... within is time-like, but instead of flowing towards the singularity, it flows away, and the event horizon is now a ...
  • 09:29: This law defines the direction of the flow of time.
  • 09:58: However, it would immediately explode in a burst of energy as soon as entropy and time resumed their normal flow upwards and forwards.

2017-08-16: Extraterrestrial Superstorms

  • 09:49: This represents a shift from streamline to turbulent flow.
  • 09:54: Turbulent flow acts like friction, sapping energy away from the bulk rotation.
  • 13:35: YouTube Account points out that the perfect name for dark flow isn't WTF flow, but rather what the flow.

2017-08-10: The One-Electron Universe

  • 03:18: You can only see the straight parts of the flow.
  • 11:09: We call it dark flow.
  • 11:13: OKFFF1 comments that data flow must have a constant velocity and not be accelerating.
  • 11:23: ... dark flow is real and assuming it's caused by a gravitational influence beyond the ...
  • 11:50: ... Grass asks about how we can measure the direction of dark flow, given that we can only really measure the velocity components that are ...
  • 12:24: M. Paulson poked fun at astronomers for using "dark" to describe anything they don't understand-- dark matter, dark energy, dark flow.
  • 12:35: To be fair, we did workshop lots of other words, but huh matter, discombobulating energy, and WTF flow just didn't do as well in the focus group.

2017-08-02: Dark Flow

  • 00:03: There's controversial evidence that, on the largest scales, the universe is flowing.
  • 00:44: Motion due to the expansion of the universe-- what we call the Hubble flow-- is equal in all directions.
  • 01:17: We call this dark flow.
  • 04:24: ... cluster has some extra peculiar velocity in addition to the Hubble flow, then the SZ effect adds an extra Doppler shift to the CMB photons that ...
  • 05:32: Once you factor out the Hubble flow, on average, those clusters seem to be drifting in the same direction.
  • 05:38: It's like a lot of the matter in the universe is flowing toward some point beyond the edge of our universe.
  • 06:22: So the idea of a universe-wide dark flow surprised a lot of people, and made others very skeptical.
  • 06:44: Analyzing around 1,000 clusters using the new data, the Planck satellite team say that no dark flow is apparent.
  • 06:52: ... also redid their work with the Planck data and claim the dark flow is still very ...
  • 07:06: The direction of the claimed flow is towards the constellations Centaurus and Hydra.
  • 07:50: ... the Great Attractor is not causing the dark flow, because that flow seems to affect galaxies across the observable ...
  • 08:05: So what causes dark flow?
  • 09:22: Whether or not dark flow is real is still unresolved.
  • 09:40: ... if dark flow does turn out to be real, we may have detected for the first time the ...

2017-04-26: Are You a Boltzmann Brain?

  • 01:49: Any part of the universe, left to its own devices, always tends to flow back to equilibrium.
  • 02:00: And it's that flow back to equilibrium, that increase in entropy, that can be harnessed to do work.

2017-04-05: Telescopes on the Moon

  • 07:41: They'll coat it with 50 to 100 nanometers of silver, which will solidify on the slowly flowing surface.
  • 10:41: Feinstein 100 asks whether energy could be extracted from the flowing space time inside a black hole.
  • 10:48: Well, not really from the flow of space time actually inside the black hole.
  • 11:03: Hydroelectric power plants on earth do it with the flow of space time that we experience as Earth's gravitational field.

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

  • 00:49: First we'll think about what the flow of time looks like without black holes or even spacetime curvature.
  • 00:55: ... saw that this quantity that we call the spacetime interval governs the flow of cause and effect, the only reliable ordering of events in a relative ...
  • 04:36: In the mathematics the coordinate r, which once represented distance, now grants the negative sign needed to maintain your causal flow.
  • 08:05: As we fall with the faster than light flow of space time, we overtake light that is outward pointing.
  • 12:02: The systems that were tested use electron spins, which pull on each other to cause a cascading flow of flipping spins the cycles back and forth.

2017-03-22: Superluminal Time Travel + Time Warp Challenge Answer

  • 01:32: We've spent some time talking about how these contours define the flow of causality.
  • 10:23: Reverse the flow of time, and you reverse the flow of you.

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

  • 01:35: ... the spacetime diagram into a 3D graph, in which causality must always flow ...

2017-02-15: Telescopes of Tomorrow

  • 11:17: The resulting shape illustrates the direction of the flow of causality.

2017-02-02: The Geometry of Causality

  • 00:43: ... that bizarre statement, we need to think a little bit more about how the flow of time is described in ...
  • 02:35: But we want that intuition because, more than proper time, the spacetime interval defines the flow of causality.
  • 04:29: ... kind of the contours defining the gradient of causality down which time flows, and etched into spacetime by the equations of special ...

2017-01-19: The Phantom Singularity

  • 08:18: But remember, for sub-light speed world lines, the space time interval tells us the rate of flow of proper time.

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

  • 07:25: ... than its own Swarzschild radius, an event horizon forms as spacetime flows faster than the speed of light towards that superdense region of ...

2016-12-21: Have They Seen Us?

  • 15:44: So you could resist the faster-than-light flow of space within the black hole.
  • 16:59: The correct way to get this number is by using general relativity to find the point where the flow of spacetime reaches the speed of light.

2016-12-14: Escape The Kugelblitz Challenge

  • 02:30: Space and time switch places, and the singularity soon forms, with all space within the black hole flowing towards it faster than the speed of light.

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

  • 06:21: Space flows at greater than the speed of light inwards, towards the central singularity.
  • 06:28: It becomes uni-directional, flowing inexorably downwards, just as time flowed inexorably forward in the outside universe.
  • 10:00: All space-time within the black hole is flowing toward the singularity faster than the speed of light.

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

  • 09:50: Relativity requires that causality is preserved, so no faster than light information flow.

2016-08-17: Quantum Eraser Lottery Challenge

  • 00:00: [MUSIC PLAYING] The quantum eraser experiment tantalizes us with the apparent instantaneous flow of information between entangled photon pairs.

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

  • 08:00: The lightspeed flow of spacetime at the event horizon results in old light paths pointing inwards.

2016-03-23: How Cosmic Inflation Flattened the Universe

  • 10:39: So even though the gas originally had motion in many directions, over time, it sweeps into a single bog flow.

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.
  • 09:05: And all of the gas gets swept into the same swirling flow.

2016-02-03: Will Mars or Venus Kill You First?

  • 03:21: ... leached of oxygen, starving your brain, and at some point blocking blood flow all ...

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

  • 03:46: Now we'll get back to why this is a good measure of the flow of time in a minute.
  • 05:57: This means that the flow of time is not a universal thing.
  • 06:06: But there's no global rate of time flow that everyone can agree on.
  • 06:10: What defines that local time flow?
  • 08:09: Now here's something that seems to be a more concrete reality than the flow of time.
  • 09:01: But what defines the direction of the flow of time?

2016-01-13: When Time Breaks Down

  • 00:41: While our memories layer over the course of our lives, and in their ordering, we see the flow of years.
  • 01:28: But do the individual components of the clock feel the same flow of time?
  • 01:56: See, the flow of time depends fundamentally on motion.
  • 02:22: The familiar smooth flow of time only emerges as these particles are bundled into what we think of as matter.
  • 03:26: The rate of ticks is consistent, time flows smoothly, until the clock starts moving relative to me.

2016-01-06: The True Nature of Matter and Mass

  • 00:02: NARRATOR: Einstein showed us that matter, mass, and the flow of time are intrinsically connected, but opened the question, are they even real?
  • 07:23: The presence in the flow of energy and momentum as well as pressure all have their quite different effects on the curvature of space-time.

2015-12-16: The Higgs Mechanism Explained

  • 05:34: ... poor electron is bombarded by a flow of particles into and out of the Higgs field from all directions, giving ...

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

  • 00:36: ... statements about reality and yet the mathematical description that flowers from those statements describes our universe with stunning ...

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

  • 01:31: Move the ball around, and I create a series of ripples that flow outwards on the sheet, similar to the ripples on a pond.

2015-07-29: General Relativity & Curved Spacetime Explained!

  • 07:25: But here's the flow chart level answer.

2015-07-02: Can a Circle Be a Straight Line?

  • 00:36: ... next few episodes I'm going to try to give you a sense of the answer, a flow chart level view of the relevant concepts and how they add up to the ...

2015-04-15: Could NASA Start the Zombie Apocalypse?

  • 01:35: More infectious bacteria flown on subsequent shuttle missions showed similar changes.
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