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

  • 19:51: ... would also have a much harder spectrum - so a lot more nasty UV light, not to mention x-rays and gamma rays, ...

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

  • 01:43: ... lines - sharp peaks in the light observed when we break it up into a spectrum of different ...
  • 01:55: For example this is the spectrum of Hydrogen.

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

  • 05:16: ... instruments that allow it to take images as well as break light up into spectra, with sensitivities from visible red light through the slightly longer ...
  • 05:32: ... has various other tricks, like the ability to take spectra of many objects at once; or using a coronagraph to block the bright ...

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

  • 17:31: We don’t see these plasmas actually freeze - just that their spectrum is changed a bit from the typical thermal spectrum of hot matter.

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

  • 05:11: ... metallicity - by looking  for the dips and spikes in a star’s spectrum   that result from specific elements sucking up  or producing light ...
  • 05:58: ... Spectra on their own aren’t really enough to tell if   two stars came ...

2022-04-20: Does the Universe Create Itself?

  • 01:59: ... consistent reality? Solutions to this seeming paradox spanned the spectrum. For example, the Hungarian physicists John von Neumann and Eugene Wigner ...

2022-03-08: Is the Proxima System Our Best Hope For Another Earth?

  • 03:22: ... clue to its uniqueness was in its emission lines - sharp spikes in its spectrum resulting from electron transitions in the atoms and molecules of the ...
  • 04:58: But the more edge-on the orbits, the more motion there is in the radial direction, and so the more chance of spotting the wiggling spectrum.

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

  • 03:02: ... consciousness collapses the wave function. At the opposite end of the spectrum, many physicists believe that the collapse of the wave function is a ...

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

  • 03:05: ... the Sun produces a thermal spectrum - light generated by its 6000K surface is distributed at all ...
  • 03:24: ... the process they warm up, shedding all of that energy as a new thermal spectrum, now at 300 or so Kelvin, with its peak at infrared ...
  • 07:20: Each would produce its own thermal spectrum at different temperatures.
  • 07:31: Two pure thermal spectra would be stitched into one weird spectrum with too little light at visible wavelengths and too much at infrared wavelengths.
  • 07:41: If we carefully broke up the star’s light with spectrographs spanning a huge wavelength range, we might be able to see two distinct thermal spectra.
  • 08:17: For something with a pure thermal spectrum, we can exactly identify its temperature from, say, the ratio of red light to blue light.

2021-09-21: How Electron Spin Makes Matter Possible

  • 14:00: ... the energy level spectrum becomes unbounded from below, meaning you can continually remove energy ...
  • 16:27: ... ridiculously expensive digital detector and spectrograph could take a spectrum of a bright quasar and see the different components of that light vary ...

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

  • 02:36: We do this by watching how the spectrum of the quasar changes over time.
  • 02:41: A spectrum, by the way, is what you get when you split light into its component colors or wavelengths.
  • 05:15: In a normal spectrum we see the light from these electron transitions as sharp spikes at specific wavelengths - what we call emission lines.
  • 05:46: ... broad emission lines - perhaps the most striking feature of the quasar spectrum, and one that confused the hell out of the astronomers who first saw ...

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

  • 02:28: The distribution of particle energies should follow a blackbody spectrum, as though the black hole has a real temperature.
  • 05:49: You no longer have a smooth, statistical spectrum to your thermal radiation - the black hole will leak its remaining mass in sudden, discrete steps.
  • 09:14: ... also, but long story short: if black holes radiate a perfect thermal spectrum then, by definition, that radiation has maximum entropy and contains no ...

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

  • 02:53: ... we’re going to go through the mass spectrum of black holes, and close one window after another - we’ll see at the ...
  • 05:37: We’ll begin with the extreme ends of the mass spectrum - those are easy.
  • 06:00: At the opposite end of the mass spectrum we have the black holes under a billion tons or around the mass of a small mountain.
  • 07:36: Ok, let’s move up the black hole mass spectrum to masses around that of a planet.
  • 10:37: We have some evidence ruling out most of the black hole mass spectrum as the main source of dark matter.

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... ultimately the result will be a distribution of wave frequency a spectrum for the background and the shape or the slope of that spectrum will help ...

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

  • 01:12: ... when the great Danish physicist Niels Bohr set about to explain emission spectra - the sharp bands of color produced when a simple tube of gas is ...
  • 01:22: ... colors of light produced by a heated object - the so-called blackbody spectrum - by assuming that light is made up of irreducible packets of energy ...
  • 01:56: ... neatly explained the specific frequencies of light observed in emission spectra of hydrogen - although it failed for more complex elements Bohr’s work ...
  • 02:18: Ultimately, these successfully predicted the spectra of elements of any complexity - and much more besides.
  • 05:10: He argued that the same emission spectra could be got by thinking of these levels as fundamental vibrational modes, like on a drum or guitar string.

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

  • 09:18: Energy could be spread more evenly across the electromagnetic spectrum, which would look like cooling - the star might appear cooler than it should.

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

  • 03:06: ... is a modern spectrum of the Sun - it’s the amount of light we receive at different colors - ...
  • 03:35: But on its own, that thermal light is a very smooth curve across the spectrum.
  • 05:32: ... the spectrum of the Sun was first studied, it was noticed that the most prominent ...
  • 06:25: One of the reasons for the complexity of stellar spectra is that you don’t just get one pattern of absorption lines per element.
  • 08:36: Cecilia Payne set about analyzing the many spectra of stars that had been observed at Harvard Observatory.

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

  • 00:00: ... other both through the semiconductors and through electromagnetic spectrum all of the wonders of theoretical physics more or less powered the ...

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

  • 00:00: ... i i should clarify what i subscribe to also because um there's a broad spectrum of views as to what to make of this apparent usefulness of math and ...

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

  • 03:34: ... case it corresponded to an explosion observed across the electromagnetic spectrum - energy released as the neutron stars tore themselves apart in their ...

2020-04-14: Was the Milky Way a Quasar?

  • 05:05: The difference in energy distributions - or in their gamma ray spectra, means that the diffuse gamma ray background can be cleanly subtracted.
  • 05:25: Now that’s pretty clear from the shape of the spectrum alone.

2019-12-02: Is The Universe Finite?

  • 05:23: More accurately, they analyzed what we call the power spectrum.
  • 05:47: We talked about the power spectrum in enormous detail in that earlier episode.
  • 05:52: One thing that we didn’t talk about is how gravitational lensing influences the overall shape of the power spectrum.
  • 06:22: ... CMB, this results in a sort of smoothing or blurring out of the power spectrum- the peaks are less sharp than they would be ...
  • 07:25: They found the range of models that fit the shape of the power spectrum, and for the most part those pointed to positive curvature.

2019-10-07: Black Hole Harmonics

  • 11:09: The last was the incredible binary neutron star merger that was also detected across the electromagnetic spectrum as a giant explosion.

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

  • 00:33: ... of carbon dioxide released into the atmosphere At the other end of the spectrum is the energy released when particles of matter and antimatter are ...

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

  • 03:27: For example, visible light – the wavelength range that our eyes are sensitive to – spans only a tiny fraction of the spectrum.
  • 04:53: ... records how much energy is received at each wavelength. We called that a spectrum. ...
  • 05:35: There's a broad blank patch in the quasar's spectrum – it's a stretch of nothing that tells us a ton.
  • 07:27: ... are other ways humanity can see the universe beyond the electromagnetic spectrum that we observe with traditional ...

2019-06-17: How Black Holes Kill Galaxies

  • 14:00: But you might see the result of it's decay a particular spectrum of radiation and cosmic rays.

2019-05-16: The Cosmic Dark Ages

  • 05:45: ... This produced a slight dip in the the cosmic microwave background spectrum. The absorbed wavelength has now been stretched – redshifted – by the ...
  • 10:10: ... is the spectrum of a quasar from the epoch of reionization. All of this light comes from ...
  • 10:47: ... clouds of neutral gas, each of which cut a narrow slice out of the spectrum. ...

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

  • 02:05: ... what we see The best way to show this is with what we call a power spectrum It's really just like a histogram that plots the number of spots of ...
  • 11:14: ... once during this brief time should be enhanced Their peaks on the power spectrum should be raised compared to the larger fluctuations So by looking at ...
  • 14:23: ... of the baryon-acoustic oscillation the actual source or our CMB power spectrum Let's see what you guys had to say flux_capacitor and Marcus Kunrath ...

2019-01-24: The Crisis in Cosmology

  • 08:47: ...with what we call a power spectrum,...
  • 09:18: ...could give the power spectrum observed by Planck.
  • 09:35: ...but the Planck power spectrum is so rich with information, that the Planck team...

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

  • 00:58: For example, Max Planck used a quantization trick to figure out the spectrum of light emitted by hot objects.

2018-10-03: How to Detect Extra Dimensions

  • 01:42: ... was followed by a glow across the electromagnetic spectrum and, ultimately, with the discovery of the distant galaxy in which the ...

2018-06-20: The Black Hole Information Paradox

  • 03:13: According to Hawking's calculation, those particles should come out with energies that follow the black-body spectrum.

2018-05-09: How Gaia Changed Astronomy Forever

  • 02:28: It measures brightness in both the red and blue parts of the electromagnetic spectrum.

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

  • 05:23: The black-body spectrum of a hot object emits relatively more photons at short energetic wavelengths than a cooler object.
  • 05:31: For most of its life, the spectrum of a red dwarf peaks at infrared wavelengths.
  • 05:42: But as these stars heat up, their spectrum shifts.
  • 05:46: First, they shine white as their black-body spectrum spans the visible range, just like our Sun.

2018-04-25: Black Hole Swarms

  • 06:50: But these polars produce a very different spectrum to X-ray binaries.
  • 07:03: That allow the researchers to weed out the X-ray sources that had the wrong spectra.

2018-04-18: Using Stars to See Gravitational Waves

  • 02:51: But then also across the electromagnetic spectrum.
  • 11:14: Without life, Earth would reflect a higher intensity spectrum closer to the 6,000 Kelvin thermal spectrum it receives from the sun.
  • 11:23: ... lot of that light and radiates something closer to a 300 Kelvin thermal spectrum. ...

2018-04-04: The Unruh Effect

  • 06:31: Those particles should have the same type of spectrum as Hawking radiation, a thermal spectrum.

2018-03-21: Scientists Have Detected the First Stars

  • 03:00: That should look like a dip in the CMB spectrum.
  • 03:43: So the research team added together the CMB light from the entire visible sky and recorded this spectrum.

2018-03-15: Hawking Radiation

  • 10:17: ... example, in 2001, Parikh and Wilczek got the same thermal spectrum for Hawking radiation by thinking about particles escaping from beneath ...

2018-01-31: Kronos: Devourer Of Worlds

  • 03:43: Well, the researchers checked their spectra, and this is where things got weird.
  • 03:49: Stellar spectra are thick, with sharp emission and absorption features that result from electron transitions in atoms in the star's atmosphere.

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

  • 11:45: Those photons would have a perfect black body spectrum.

2018-01-17: Horizon Radiation

  • 13:32: The frequency spectra for resonant oscillations of several stars were shifted to a range audible to human hearing.

2017-12-22: Space Time VR

  • 00:16: ... ideas in astrophysics in which we explore the electromagnetic spectrum, the speed of light, and time ...

2017-11-29: Citizen Science + Zero-Point Challenge Answer

  • 08:22: That corresponds to a photon wavelength of a tenth of a millimeter, which is in the far infrared part of the spectrum.

2017-10-25: The Missing Mass Mystery

  • 02:43: Baryonic matter interacts with light, so we can search for it by scanning the electromagnetic spectrum.
  • 04:51: ... the distribution and speckle sizes in what we call the CMB power spectrum, we can find the relative amount of baryonic versus dark ...

2017-10-11: Absolute Cold

  • 02:15: This quantum nature is revealed when we look at the spectrum of light produced as those particles hop between energy levels.
  • 02:34: The influence of the quantum world becomes far more apparent in the strange states of matter that exist at the cold end of the heat spectrum.

2017-10-04: When Quasars Collide STJC

  • 06:02: Well, the researchers tested this by looking at multiple frequencies to get a crude radio spectrum.

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

  • 04:48: We see this effect in the sharp spikes or dips in light at specific wavelengths when we observe the spectrum of a gas.

2017-09-13: Neutron Stars Collide in New LIGO Signal?

  • 10:06: But colliding neutron stars are bright across the electromagnetic spectrum.

2017-08-24: First Detection of Life

  • 00:47: ... a plan devised by, among others, Carl Sagan, Galileo would measure the spectrum of Earth's atmosphere, take pictures, and look for radio emission during ...
  • 01:47: ... at the spectrum taken with its near-infrared spectrometer you can see these deep dips ...
  • 06:06: Galileo also observed the spectrum of Earth's surface and took color photographs.
  • 07:12: While we need to travel far to get high res pics of an exoplanet, we finally succeeded in taking spectra of their atmospheres without leaving home.
  • 08:12: The spectra revealed the presence of water, methane, and carbon dioxide.

2017-06-07: Supervoids vs Colliding Universes!

  • 05:46: ... wavelengths and determined the shift in the wavelengths of those spectra due to the expansion of the universe, i.e., they measured ...
  • 12:48: ... of a star or a galaxy, you need to be able to split the light into a spectrum and look for emission lines, light at the signature wavelengths of ...

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

  • 00:54: When the sun's light is broken into a spectrum, it reveals traces of many of the heavier elements of the periodic table.

2017-04-05: Telescopes on the Moon

  • 01:25: Two, Earth's atmosphere blocks all but a few narrow windows of the electromagnetic spectrum.
  • 01:31: From the moon, the entire spectrum is accessible.

2017-02-15: Telescopes of Tomorrow

  • 00:22: ... is the most important observatory ever built. Its stunning images and spectra have opened up incredible windows on our ...
  • 07:23: ... photographs of planets in other solar systems and even to observe the spectra of the atmospheres of some ...

2017-01-25: Why Quasars are so Awesome

  • 02:46: Astronomers turned their optical telescopes on this strange star, and split the light into a spectrum.
  • 02:53: It looked nothing like the spectrum of any star ever seen.
  • 03:05: For one thing, its spectrum was redshifted, the wavelength of its light stretched out as those photons traveled through the expanding universe.

2016-12-21: Have They Seen Us?

  • 02:44: ... into the so-called water hole, a narrow frequency range in the radio spectrum between a pair of H and OH emission spikes, which itself is within the ...
  • 07:58: That redshifted early hydrogen emission is now found slap in the middle of the noisy lower frequency part of our own TV broadcast spectrum.

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

  • 10:28: We recently talked about the origin of quantum theory with Max Planck's derivation of an equation to describe the black body spectrum.
  • 11:05: The sun does emit a bit more light in the yellowy green part of the electromagnetic spectrum compared to the blue and the red parts on either side.
  • 11:14: This is due to its black body spectrum peaking in that yellowy green region.
  • 11:25: Our eyes can't register the difference in brightness across the visible part of the spectrum, so we register the color as white.

2016-06-22: Planck's Constant and The Origin of Quantum Mechanics

  • 03:42: The sun is yellow because its 6000 Kelvin surface produces more photons in the green yellow part of the electromagnetic spectrum than anywhere else.
  • 04:43: The resulting blackbody spectrum looks like a lopsided bell curve.
  • 04:54: The key to unlocking the mystery lay in finding a mathematical description for the blackbody spectrum.
  • 05:36: The resulting Rayleigh-Jeans law described the blackbody spectrum perfectly.
  • 07:09: ... searching for a new mathematical approach to deriving the blackbody spectrum, he needed some sort of math trick to count the supposedly infinite ...
  • 08:11: Planck's new equation described the shape of the blackbody spectrum exactly, across all frequencies of light.
  • 08:59: ... given a mathematical form for the blackbody spectrum, it was possible to do this just by varying the constant until the Planck ...
  • 10:38: ... defining the shape of the blackbody spectrum, the Planck constant can be read in the color of the sun and the stars, ...
  • 14:21: This can change the power spectrum, so the distribution of the sizes of its blobs, which is really important for measuring cosmological parameters.

2016-06-08: New Fundamental Particle Discovered?? + Challenge Winners!

  • 02:00: ... gamma ray flashes at 125 gigaelectron volts above the otherwise smooth spectrum of gamma ray ...

2016-02-11: LIGO's First Detection of Gravitational Waves!

  • 05:55: ... simultaneously using multiple telescopes that span the electromagnetic spectrum from radio to visible to ...
  • 06:28: However, now that we know that these things are detectable, it opens up an entirely new spectrum for observing the universe.
  • 06:35: ... Space Antenna-- eLISA-- will see an entirely different part of this spectrum, much lower frequencies, opening the possibility to observe completely ...

2015-05-27: Habitable Exoplanets Debunked!

  • 04:01: That graph of brightness versus wavelength is called an object's spectrum.
  • 04:05: Since different atoms and molecules emit or absorb particular wavelengths of light only, the spectrum tells you a lot about atmospheric composition.
  • 04:47: You take a spectrum of the star when the planet is in front of it.
  • 04:50: This will be the combined spectrum of the planet and star.
  • 04:53: And then you take another spectrum when the plan is behind the star.
  • 04:55: That gives you the spectrum of the star alone.
  • 04:57: Subtract the two, and you get the spectrum of just the planet.

2015-03-25: Cosmic Microwave Background Explained

  • 01:56: ... pattern represented by the graph is called the toaster's thermal spectrum or really an idealization of a thermal spectrum called a black body ...
  • 02:04: Now, everything has a temperature, so everything has a thermal spectrum, and it emits all electromagnetic wavelengths.
  • 02:12: In fact, it's called a thermal spectrum because the light is generated by the random motions of particles in the material.
  • 02:32: The CNB is one of the closest things to a mathematically perfect thermal spectrum that has ever been observed.
  • 02:47: So why does the CNB look like a thermal spectrum at all?
  • 04:37: ... over the course of a few million years, that orangey thermal spectrum of light was redshifted to longer and longer wavelengths, becoming ...
  • 05:10: ... the CNB, or more specifically, the shape of its thermal spectrum, is pretty compelling evidence that when it comes to the color of space, ...

2015-02-25: How Do You Measure the Size of the Universe?

  • 03:22: In more extreme cases, the wavelength can be stretched out of the visible spectrum altogether, into microwaves or radio waves.
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