
20221208: How Are Quasiparticles Different From Particles?
 06:01: In this case, the crystal lattice can vibrate at any frequency, but the amount of energy at each vibrational mode can only go up in discrete chunks.
 06:47: They have energy equal to the planck constant times their frequency.


20221109: What If Humanity Is Among The First Spacefaring Civilizations?
 18:50: ... field theory, with the timereversed signals corresponding to negative frequency ...


20220824: What Makes The Strong Force Strong?
 18:36: Those fields have positive and negative frequency modes that cancel each other out to leave a vacuum.


20220803: What Happens Inside a Proton?
 13:36: ... has accurately predicted many things, from masses and decay frequencies of hadrons to the exotic properties of quarkgluon ...


20220622: Is Interstellar Travel Impossible?
 19:30: Hawking’s original argument talked about perturbing the positive and negative frequency modes of the quantum vacuum.


20220323: Where Is The Center of The Universe?
 18:31: ... signals that were not clearly associated with stars and had radio frequency spacing similar to Earthly ...


20211229: How to Find ALIEN Dyson Spheres
 05:40: So yeah, we could go flicking through the frequency channels of gas clouds looking for alien TV shows.


20211220: What Happens If A Black Hole Hits Earth?
 00:29: ... to pass through our solar system  and even the planet  with startling frequency. In fact it may have already ...


20210915: Neutron Stars: The Most Extreme Objects in the Universe
 10:06: ... big splash and a crash, it’s a continuous hum at exactly one frequency twice the frequency of the neutron star’s rotation ...
 11:29: ... dissipation of these vortices is seen by us as glitches in the frequency in the flashes of pulsars. The rare cooperpair protons on ...


20210810: How to Communicate Across the Quantum Multiverse
 00:23: ... that move independently of each other, in exactly the combination of frequencies and amplitudes to encode me talking about ...


20210616: Can Space Be Infinitely Divided?
 01:16: ... the chunkiness of thermal radiation. Multiply the frequency of the light by this number and you get the energy of a single ...


20210519: Breaking The Heisenberg Uncertainty Principle
 09:43: But that noise is less of a problem than the phase uncertainty, at least for the higher frequency gravitational waves.


20210511: How To Know If It's Aliens
 10:35: ... of radio emission appeared at 982.002 MHz and then drifted upwards in frequency over a 3 hour observation. This weird signal was only spotted over a ...
 11:24: ... published its findings so we can’t say much  we know the increase in frequency is consistent with the Doppler shift of something accelerating towards ...


20210407: Why the Muon g2 Results Are So Exciting!
 09:57: We call this Larmor precession, and its frequency depends on the gfactor.
 10:02: The frequency of the precession also governs the energy of the particles that these muons decay into.


20210323: Zeno's Paradox & The Quantum Zeno Effect
 06:18: Next they flash the atoms with a laser whose frequency matches the energy difference between state 1 and a new state, state 3.
 15:16: But the important thing is that the amplitude of the wave is directly encoded in the frequency of the wave.
 15:21: ... black holes spiral towards each other, the frequency of the last phase of the inspiral is pretty uniquely determined by the ...
 15:38: So, measuring the inspiral frequency gets you the power  which you can think of the amplitude before it fades over distance.


20210309: How Does Gravity Affect Light?
 03:18: Wavelength increases, which means frequency and energy drop.
 04:10: These are the ticks of a clock, and the frequency dictates the frequency and the wavelength of the photon produced by that motion.
 04:18: But from a great distance away, those clocks run slow, and so the frequency of light emerging from within a gravitational field is lower.
 04:37: ... hole, gravitational time dilation is so strong that clocks stop and the frequency of photons trying to escape is brought to ...
 06:00: ... for the prediction  the difference in the flow of time changes the frequency of outgoing ...


20210217: Gravitational Wave Background Discovered?
 00:00: ... has a fundamental limit it can only see those gravitational waves with frequencies around 1 to ten thousand hertz corresponding to relatively compact waves ...


20210112: What Happens During a Quantum Jump?
 01:56: ... attempt at a quantum theory, and it very neatly explained the specific frequencies of light observed in emission spectra of hydrogen  although it failed ...
 06:28: ... atom  in this case mercury or barium  is bathed in a laser beam with a frequency exactly tuned to the energy difference between two of its electron ...
 07:37: Now flash a second laser with frequency tuned to take the electron from level 1 to level 3.


20201005: Venus May Have Life!
 12:15: The discovery of alien life in our nearest planetary neighbor would totally change our calculations about the frequency of life in the universe.


20200921: Could Life Evolve Inside Stars?
 14:01: ... periodic function can be represented as a sum of sine waves of different frequencies. ...


20200901: How Do We Know What Stars Are Made Of?
 03:06: ... colors  or in other words, from photons of different energies of frequencies. ...


20200708: Does Antimatter Explain Why There's Something Rather Than Nothing?
 09:19: ... properties in antimatter versus matter will cause a shift in the laser frequency necessary to stimulate a transition in the atoms. Scientists measure ...


20200622: Building Black Holes in a Lab
 06:33: ... in these analog black holes. Or at least, the perturbations in the frequencies of the surface ripples have properties that are closely analogous to ...


20200615: What Happens After the Universe Ends?
 14:49: ... patreon supporters will have their names encoded in the orbital frequencies of colliding suppermassive black holes at the end of time to be ...


20200608: Can Viruses Travel Between Planets?
 04:43: ... an alien world passes in front of its home star, we can see signatures frequencies plucked from the starlight due to it passing through that planet’s ...


20200224: How Decoherence Splits The Quantum Multiverse
 03:11: ... wave mechanics, we say that a set of waves are coherent if they match in frequency and if the shape of the waves are the same, and if there’s a constant ...


20200127: Hacking the Nature of Reality
 00:43: ... depend only on observable quantities  in this case, the mysterious frequencies of light produced as electrons jump between ...
 15:01: ... causes the black holes to merge faster, so that should increase the frequency of the those waves and to a lesser extend the actual shape of the ...


20191007: Black Hole Harmonics
 02:43: When struck, a bell vibrates with many different frequencies – many overlapping harmonics.
 02:56: A “struck” black hole also vibrates with many different harmonic frequencies.
 03:12: In the latter cases we can describe a vibrating string as a series of standing sine waves of different frequencies, all happening at the same time.
 03:22: ... lowest frequency the string can support is called the fundamental mode – it’s usually the ...
 03:34: Higher frequency modes are called overtones, and they provide richness and texture to the sound.
 03:40: The full set of possible frequencies a string can support are called its harmonics.
 04:05: ... a single, pure oscillation on that spherical surface with a set frequency. ...
 07:35: In astronomy, the analysis of the different frequencies of light is called spectroscopy.
 07:41: So this sort of frequency analysis of gravitational waves is being called gravitational wave spectroscopy.
 10:19: ... researchers test the nohair theorem by checking whether the frequency of oscillations and the time for the decay of those oscillations agrees ...


20190306: The Impossibility of Perpetual Motion Machines
 14:04: We know where the sources of this emission are from observations at other frequencies and can do pretty well modeling and subtracting them.


20190207: Sound Waves from the Beginning of Time
 05:26: ... free electrons were able to interact with any frequency of light, electrons bound into atoms are restricted to only those ...


20181220: Why String Theory is Wrong
 08:17: These strings are vibrating with standing waves like guitar strings, and their energy also depends on the frequency of that vibration.
 08:25: That frequency depends on the density of wave cycles on the string.
 08:30: ... have a large mode number with a small radius and that gives you a high frequency ...


20181206: Did Life on Earth Come from Space?
 00:37: ... may be able to hibernate that long but at this point the issue is just frequency of impacts is it at all likely that a microbe bearing rock from another ...


20181114: Supersymmetric Particle Found?
 06:37: ... in the ice anywhere within 700 kilometers of ANITA, the resulting radio frequency Cherenkov can be seen by ANITA'S ...


20181025: Will We Ever Find Alien Life?
 07:23: ... of these stars that form habitable worlds, biological factors like the frequency of the appearance of simple life and the proportion of those that lead ...


20181018: What are the Strings in String Theory?
 06:12: All other frequencies tend to die out.
 06:14: The result is that for a given string, only certain frequencies corresponding to certain energies are possible.
 06:22: These resonant frequencies depend on the length of the string, also its tension, which defines wave velocity and so relates frequency to wavelength.
 06:31: For example, this leads to the specific frequencies of vibration on a guitar string.


20181003: How to Detect Extra Dimensions
 10:20: ... of the merger event namely, the masses of the merging objects and the frequency of the wave combined with our independent distance ...


20180920: Quantum Gravity and the Hardest Problem in Physics
 07:01: ... from a wide range of momentum wave functions that include extremely high frequencies or extremely high momenta, i.e., the more certain its position, the less ...


20180418: Using Stars to See Gravitational Waves
 03:28: But with its four kilometer arm length, it's only sensitive to a frequency range from around 1 hertz to 10 kilohertz.
 03:35: ... roughly corresponds to the frequency of the binary orbits just before merger, which for black holes and ...
 03:47: The more massive the binary, the lower the frequency.
 07:32: Stars oscillate at particular frequencies.
 07:38: If a gravitation wave frequency matches the natural resonant frequency of a star, oscillations can be set up inside the star.


20180404: The Unruh Effect
 06:00: And just as with Hawking radiation, that horizon cuts off your access to certain fundamental frequency modes of the quantum vacuum.
 06:20: ... here they also lead to a mixing of positive and negative frequency modes in the accelerating frame of reference, which leads to the ...


20180315: Hawking Radiation
 02:55: They can oscillate with different frequencies, much like the many possible vibrational modes on a guitar string.
 03:32: One way that quantum fields are very different to guitar strings is they can have both positive and negative frequencies.
 03:39: A negative frequency can be thought of as a mode that travels backwards in time and can be interpreted as corresponding to antimatter.
 03:51: ... is in a vacuum state, there's a balance between positive and negative frequency modes, which you can crudely think of as a balance between virtual ...
 06:30: They describe a sort of mixing of the positive and negative frequency vibrational modes that are caused by that curved space.
 07:39: Hawking calculated the frequency distribution of this radiation and found something incredible.
 08:13: So Hawking's math describes splitting or mixing of these pure positive and negative frequency modes.
 10:05: We can think about positive and negative frequency modes being mixed due to scattering, perhaps, by the as yet undiscovered graviton.


20180117: Horizon Radiation
 05:28: Sound waves can be described in terms of variation over time or variation over frequency.
 07:21: ... with an infinite drumstick, adding global vibrations with different frequencies that cancel out everywhere except that one ...
 13:32: The frequency spectra for resonant oscillations of several stars were shifted to a range audible to human hearing.


20180110: What Do Stars Sound Like?
 01:33: ... the stellar interior, setting up global oscillations, natural resonant frequencies that carry information about stars impenetrable ...
 04:08: The distribution of the pattern depends on the frequency or the mode, much like on the skin of a drum.


20171213: The Origin of 'Oumuamua, Our First Interstellar Visitor
 04:57: PZ 17 performed computer simulations to find the frequency of such kicks sending objects close to the earth at such high speeds.
 10:30: How can a photon's frequency be generalized as momentum?
 10:33: Does frequency then include information about direction of motion?
 10:36: Well we generalize frequency as momentum because the Heisenberg uncertainty principle applies to momentum in general.
 10:50: So that uncertainty is all in their frequency.
 10:53: And yes, also in their direction of motion, which is separate to frequency.


20171206: Understanding the Uncertainty Principle with Quantum Fourier Series
 02:55: The sound wave for a simple pure tone, like a middle C, is a sinusoidal wave, with the frequency determining the pitch of the tone.
 03:03: ... be broken down into a combination of many simple sine waves of different frequencies. ...
 03:23: ... sound wave can be decomposed into a number of sine waves of different frequencies, each with a different strength, stacked on top of each other or ...
 03:36: ... intensity changing with time, you can also represent it in terms of its frequency components, each with its own weighting or ...
 03:48: When you switch between a time and a frequency representation, you're doing a Fourier transform.
 03:55: In fact, digital audio equipment stores, manipulates, and transmits sound in its frequency representation.
 04:02: In the physics of sound, time and frequency have a special relationship because any sound wave can be represented in terms of one or the other.
 04:18: So we can make any shape sound wave with a series of sine waves of different frequencies.
 04:24: ... example, you can build a wave packet by adding frequency components with the right phases to destructively interfere everywhere ...
 04:35: The tighter you want to make that time window for the wave packet, the more frequency components you need to use.
 04:41: ... those steep edges of the wave packet, you need to add higher and higher frequencies, because the high frequency components are the ones that give you rapid ...
 05:12: ... a spike at one point in time, you need to use infinitely many different frequency sine waves, each of which exists at all points in ...
 05:22: So then if we make a sound that is perfectly located in time, it doesn't have a frequency, or it has all frequencies.
 05:30: ... the same time, a sound wave with a perfectly known frequency is a simple traveling sine wave that extends infinitely in time so the ...
 05:41: That sounds an awful lot like a frequencytime uncertainty principle for sound waves.
 05:47: ... uncertainty principle, it's more a statement about the sampling of frequencies needed to produce a given wave ...
 06:15: Like the sound wave, it oscillates through space at a particular frequency.
 06:39: The second of this pair is momentum, not frequency.
 06:43: See, momentum is sort of the generalization of frequency for what we call a matter wave.
 06:49: In the early days of quantum mechanics, it was realized that photons are electromagnetic wave packets whose momentum is given by their frequency.
 06:58: ... and his De Broglie relation generalizes the relationship between frequency and momentum of a matter ...
 07:08: ... just as a traveling sound wave can be expressed in terms of time or frequency. ...
 07:41: And of course, this means that position and momentum have the same kind of uncertainty relation that time and frequency had in the sound wave.


20171129: Citizen Science + ZeroPoint Challenge Answer
 06:57: ... from assuming that there are no virtual photons above a certain cut of frequency. ...
 07:06: ... you choose that to be the frequency corresponding to a photon with the Planck energy, you get a vacuum ...
 07:18: In this theoretical estimate, vacuum energy density is proportional to the fourth power of cutoff frequency.
 07:25: So my question was what cutoff frequency is needed for this theoretical estimate to give you the energy density implied by dark energy?
 07:49: The frequency of a photon with the Planck energy is the Planck energy divided by the Planck constant, or an insane 3 by 10 to the power of 42 hertz.
 07:59: And if vacuum energy is proportional to the fourth power of cutoff frequency, then this equation gives the relationship we need.
 08:07: There are a bunch of constants in the cutoff frequency vacuum energy relation, but they cancel out.
 08:17: So we get a cutoff frequency for dark energy of 3 by 10 to the power of 12 hertz.
 08:32: ... the simplistic approach of choosing the right maximum virtual photon frequency definitely can't give us the vacuum energy that we see as dark ...


20171108: ZeroPoint Energy Demystified
 04:31: By cutting off certain frequency modes between the plates, you lower the vacuum energy in that region.
 08:35: ... field is estimated by integrating the energy in all possible frequency modes up to some cutoff ...
 08:48: You get that the vacuum energy density is proportional to the fourth power of that cutoff frequency.
 09:00: What cutoff frequency is needed for this theoretical estimate to give the energy density implied by dark energy.
 09:09: And is this a possible maximum virtual photon frequency, given the results of Casimir experiments?


20171102: The Vacuum Catastrophe
 01:55: ... any fuel oscillation must be half of the tiny Planck constant times the frequency of that ...
 02:09: ... except to properly describe a perfect vacuum, every single possible frequency mode at every point in space must have that amount of ...
 02:23: To calculate the density of energy of the vacuum, we should add this tiny energy over an infinite range of frequency modes for all fields.
 02:55: What if there's a maximum possible frequency for virtual photons?
 02:59: Then our sum of frequency modes would be finite.
 03:07: And anyway, there's an almost sensible cutoff for photon frequency.


20171019: The Nature of Nothing
 08:51: ... string of a particular length only resonates with waves of certain frequencies, any nonresonant virtual photon would be excluded, reducing the vacuum ...
 09:05: However, on the outer surface of the plates, all frequencies of virtual photon are allowed.


20171004: When Quasars Collide STJC
 04:36: Here's the radio map at 15 gigahertz frequency.
 06:02: Well, the researchers tested this by looking at multiple frequencies to get a crude radio spectrum.
 06:14: Spiraling electrons produce radio waves a lots of frequencies all the way down to very low energies.
 09:01: And while those waves may be powerful, they have an incredibly low frequency something like 1 ten trillionth of a hertz.


20170928: Are the Fundamental Constants Changing?
 02:41: And the second is defined in terms of a particular frequency of light emitted by the cesium133 atom.


20170913: Neutron Stars Collide in New LIGO Signal?
 05:33: LIGO is sensitive to a specific frequency range.
 05:37: ... before merger, while neutron stars ring at audible gravitational wave frequencies for at least several ...


20170628: The First Quantum Field Theory
 02:03: Anyone who's ever strummed or shredded knows that a stretched string vibrates with a certain frequency when plucked.
 02:17: A larger amplitude and/or larger frequency means the vibration carries more energy.
 03:47: If this were a quantum mechanical guitar string, then there'd be a minimum amplitude for the vibration that depended on its frequency.


20170329: How Time Becomes Space Inside a Black Hole
 12:36: Firstly yeah, these time crystals oscillate at an integer multiple of the electromagnetic field frequency.
 13:38: That would be special and weird, even if the original period was defined by an external EM field frequency.


20170315: Time Crystals!
 04:36: A laser is just a very wellordered electromagnetic wave with a known period or frequency.
 05:09: ... means they should resist a change in the frequency of the input laser, or continue oscillating at least for a while if the ...


20170202: The Geometry of Causality
 13:30: ... energetic electron transition that produces Xrays at a very particular frequency, the ion Kalpha emission ...


20170111: The EM Drive: Fact or Fantasy?
 13:16: Since the 1960s, our own radio leakiness has diminished, with narrowing broadcast frequency bands, fiberoptics, etc.
 13:42: In that case, radio is still the way to go, and it's worthwhile for us to search at radio frequencies.


20161221: Have They Seen Us?
 02:44: ... peered into the socalled water hole, a narrow frequency range in the radio spectrum between a pair of H and OH emission spikes, ...
 03:23: These searches often focused on the water hole or the surrounding quiet frequency window.
 05:07: ... is that a distant civilization's radio bubble is likely to overlap in frequency with our own ...
 05:24: At around 1500 megahertz, it's in the ultrahigh frequency (UHF) band.
 05:30: Most TV broadcasts air at the tens to hundreds of megahertz of the merely veryhigh frequency (VHF) band.
 07:40: That emission, produced at 21 centimeters wavelength, or 1420 megahertz frequency, is, by definition, one of the boundaries of the waterhole.
 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.
 09:02: These emission spikes may also shift back and forth in frequency due to Doppler shift, as the distant technologically advanced planet orbits its star.
 10:31: ... out, that one month integration time requires a very consistent narrow frequency signal, which may not be consistent with typical ...
 11:56: It's pretty natural to want to scan the heavens at exactly the frequencies where we earthlings are the noisiest.


20160727: The Quantum Experiment that Broke Reality
 12:32: Bike Jake would like me to talk more about resonant frequencies.
 12:35: My pleasure a resonant frequency is when two orbiting bodies have orbital periods that form a neat ratio of small integers.
 13:03: ... each other and that pull stops them from straying out of that resonant frequency. ...


20160720: The Future of Gravitational Waves
 01:30: ... in the interferometer arm lengths that increased in both amplitude and frequency as the black holes approached before dying away again after the ...


20160622: Planck's Constant and The Origin of Quantum Mechanics
 02:12: ... orbits, and importantly, the relationship between the energy and frequency of a ...
 03:30: And so the average frequency of the resulting particles of light, of photons, increases with temperature.
 03:37: This average frequency defines the color that we see.
 03:53: The blue super giant star Rigel is 12,000 Kelvin, and so it pumps out lots of high frequency blue light and even more ultraviolets.
 04:04: Your temperature is around 310 Kelvin, so your heat glow is mostly in low frequency infrared photons.
 04:30: ... the late 1800s, the distribution of brightnesses with frequency produced by hot objects had been mapped in careful experiments the ...
 05:28: This simple idea allowed our good Englishmen to figure out the frequencies of the photons produced by all of this thermal motion.
 05:41: For low frequency, infrared light.
 05:43: But for higher frequencies, like visible and ultraviolet, it predicted brightnesses that were way too high.
 05:51: Worse, it predicted that the intensity should eventually approach infinity as frequency increased.
 06:37: ... energy got packed into the countless very tiny energy states at high frequencies. ...
 07:38: He set this minimum energy to be the frequency of a particle's vibration times a very, very small number, a number that had yet to be measured.
 08:05: Because it limited how much energy those high frequency vibrations could hold.
 08:11: Planck's new equation described the shape of the blackbody spectrum exactly, across all frequencies of light.
 09:52: ... part particle, carrying a quantum of energy equal to the now familiar frequency of the wave times the Planck ...


20160330: Pulsar Starquakes Make Fast Radio Bursts? + Challenge Winners!
 00:30: So an FRB is seen as a very quick flash of broad frequency radio emission from some spot on the sky.


20160224: Why the Big Bang Definitely Happened
 10:09: That's actually the frequency of detectable mergers predicted by some astrophysical models.


20160211: LIGO's First Detection of Gravitational Waves!
 02:57: ... are still distant from each other are far too weak, and have too low of frequency for LIGO to directly detect ...
 04:31: ... oscillations have a frequency, number of stretches and squeezes per second, that matches the rate at ...
 06:13: ... LIGO is sensitive to gravitational waves at frequencies produced by merging black holes and neutron stars, as well as the ...
 06:35: ... eLISA will see an entirely different part of this spectrum, much lower frequencies, opening the possibility to observe completely new ...


20151028: Is The Alcubierre Warp Drive Possible?
 07:31: It'll be an orbiting gravitational wave observatory designed to detect much higher frequency gravitational waves than advanced LIGO.


20150819: Do Events Inside Black Holes Happen?
 08:02: Because of time dilation, we would detect any laser pulse that the monkey sends with a lower frequency, i.e.
 08:10: ... is so severe that any light he emits gets redshifted to undetectably low frequencies. ...


20150708: The Leap Second Explained
 01:58: ... the current frequency right now of leap seconds, that arises because of a preexisting ...


20150617: How to Signal Aliens
 01:27: ... radio telescopes sending narrow pulses of highpowered microwaves at frequencies of 10 gigahertz or higher, sweeping the whole sky about once a year or ...


20150513: 9 NASA Technologies Shaping YOUR Future
 04:16: ... funded some university researchers to experiment with targeted high frequency vibrations that trick bones into thinking they're carrying weight so ...
