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2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics?

  • 02:18: Opening the box causes the observed ball to have to choose a color state, which then forces the ball on the moon to choose the opposite.
  • 03:22: They only gain specific values when  observed and the wavefunction “collapses”.

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

  • 01:43: ... energies that we observe as spectral lines - sharp peaks in the light observed when we break it up into a spectrum of different ...

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

  • 00:19: ... and exoplanet atmospheres to the earliest, most distant galaxies ever observed. ...
  • 04:28: JWST is designed to catch that light and has already observed galaxies much closer to the Big Bang than ever before.

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

  • 01:41: As physicists tried to understand the aptly named particle zoo, certain peculiar relationships were observed.

2022-07-20: What If We Live in a Superdeterministic Universe?

  • 12:53: ... observed violations of Bell’s inequality with extremely high significance, which ...

2022-06-22: Is Interstellar Travel Impossible?

  • 18:50: ... the no-hair theorem, which tells us that the only things that can be observed about a black hole from its exterior are mass, spin, and ...

2022-06-01: What If Physics IS NOT Describing Reality?

  • 01:41: ... existence is between the relationship between the observer and the observed. ...

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

  • 00:59: ... As Niels Bohr put it “no phenomenon is a phenomenon, until it is an observed phenomenon”. Bohr led the charge with this observer-dependent view, ...
  • 05:56: ... the quantum world appears to live in a state of uncertainty until it’s observed? ...
  • 09:48: ... circuit.” The relationship between the observer (us) and the observed (the universe) brought *both* into existence. Take this yet further and ...
  • 12:27: ... these acknowledge the importance of the observer in defining the observed, while still allowing that there’s some kind of substrate to reality. ...
  • 17:08: ... then it formed by a different process than the black holes that we’ve observed in our universe. The gap between the masses is too enormous for it to ...

2022-03-16: What If Charge is NOT Fundamental?

  • 05:57: Charge alone couldn’t explain the patterns of interactions and particle types observed in the particle zoo.

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

  • 13:35: ... connected to the narrow sliver of that wavefunction that represents our observed ...

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

  • 15:30: ... made a point that I missed in that MOND episode. And that's that we’ve observed galaxies that seem to be >99% dark matter as well as a few that seem ...

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

  • 00:02: ... which would give us dark energy i don't know if it agrees with what is observed um paseo achilles asks is my beer painted uh yes this is actually ...

2021-11-10: What If Our Understanding of Gravity Is Wrong?

  • 01:22: The expected rotation rates of galaxies come  from applying our laws of gravity based on the observed mass.
  • 04:08: If you tune the modification right you recover  the observed rotation curves for spiral galaxies very nicely without the need for extra mass.

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

  • 18:13: ... the particular equation that describes the precise details of a given observed phenomenon - usually by trial and error - we come at in from the other ...

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

  • 05:59: ... that holds information about the probability of a given property being observed. For example, the wavefunction representing the position of a particle ...

2021-08-03: How An Extreme New Star Could Change All Cosmology

  • 00:00: ... but instead by murmurs of “huh, that’s weird”. Well, we’ve just observed a faint point of light on the sky whose weirdness could change the way ...
  • 09:51: ... turbulent motion to jump start a dynamo powerful enough to produce the observed magnetic ...

2021-07-21: How Magnetism Shapes The Universe

  • 11:54: ... - in the polarized light surrounding the M81 supermassive black hole observed by the event horizon ...

2021-07-13: Where Are The Worlds In Many Worlds?

  • 09:48: OK, so you’ve observed the result of the experiment.
  • 09:52: Different yous have observed all results.

2021-07-07: Electrons DO NOT Spin

  • 03:48: ... - but that has huge problems. For example, in order to produce the observed magnetic moment they’d need to be spinning  faster than the speed ...
  • 06:10: ... between due to all the random orientations. But that's not what’s  observed. Instead, the atoms hit the screen in only two spots corresponding  ...
  • 12:13: ... intrinsic angular momenta can only be observed as plus or minus a half times the reduced Planck constant,   ...

2021-06-23: How Quantum Entanglement Creates Entropy

  • 16:39: ... Planck length in   that direction, which is also wrong - the observed Planck length should be independent of velocity.   Michal asks ...

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

  • 04:26: ... with a very distant zero-gravity region where the Hawking radiation is observed. ...

2021-05-19: Breaking The Heisenberg Uncertainty Principle

  • 05:58: the recombined laser no longer perfectly cancels, and so flashes of light are observed.

2021-05-11: How To Know If It's Aliens

  • 00:52: ... samples were first heated to 160 Celsius, in which case no response was observed - as you might expect if the microbes had been fried It seemed like a ...
  • 01:55: ... Now when this is done with Earth samples, new bursts of gas are always observed as the microbes wake up and start feeding. But not so in the Martian ...

2021-03-16: The NEW Crisis in Cosmology

  • 06:22: ... our good-ole Cepheid variables   in galaxies where both are observed. But those distant Cepheids are in turn calibrated based ...

2021-01-19: Can We Break the Universe?

  • 15:40: This is the first time the flourescence has been directly observed, so it lends credence to the theory.

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

  • 01:56: ... theory, and it very neatly explained the specific frequencies of light observed in emission spectra of hydrogen - although it failed for more complex ...
  • 06:21: And in 1986, almost simultaneously, three different teams observed quantum jumps in such an atom.

2020-12-22: Navigating with Quantum Entanglement

  • 09:32: Although birds do have cryptochromes, the mechanism itself has not been directly observed in a bird, and it remains only the most likely explanation.
  • 13:37: ... are entirely based on the observational properties - what elements are observed as emission or absorption lines, the way the light decays over time, and ...

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

  • 02:53: ... states that, that chunk of the universe could be in, if it were to be observed. ...
  • 03:50: ... that a quantum system is literally in a state of undefined-ness until observed. ...

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

  • 12:07: ... of the world within that cone - exist in a state of indeterminacy until observed. ...

2020-10-05: Venus May Have Life!

  • 07:23: The abiotic production rate of phosphine is expected to be 10,000 to a million times too low to produce the amount of phosphine that was observed.

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

  • 08:36: Cecilia Payne set about analyzing the many spectra of stars that had been observed at Harvard Observatory.

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

  • 01:55: ... collision experiments, all sorts of never-before-seen particles were observed allowing physicists to begin to map out the subatomic ...

2020-08-17: How Stars Destroy Each Other

  • 07:38: He observed these objects using visible wavelength of light - and found one object was indeed pulsing.

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

  • 00:00: ... waves and black holes all these zany things that have been observed experimentally it takes general relativity and it says let's quantize ...

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

  • 03:34: ... that case it corresponded to an explosion observed across the electromagnetic spectrum - energy released as the neutron ...
  • 09:33: So far we’ve never observed a black hole with masses lower than around 5 times that of the Sun.

2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing?

  • 03:38: ... baryogenesis.” But, at least at the level of CP violation that we’ve observed, this isn’t enough to explain the level of baryon asymmetry that does ...

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

  • 06:33: ... in fact Hawking-like radiation has been observed in these analog black holes. Or at least, the perturbations in the ...

2020-05-04: How We Know The Universe is Ancient

  • 03:24: ... and Jesuit priest, Georges Lemaître, suggested that Vesto Slipher’s observed redshifts could be a sign of the universe’s expansion. Lemaitre put ...
  • 07:40: ... had observed a brighter variety of Cepheids in distant galaxies, but he then used a ...

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 09:17: ... these energy conditions are more guidelines than rules, and have been observed to be violated in some cases - for example in dark energy and in the ...
  • 14:59: ... Willenberg asks whether we've observed Fermi Bubbles in other galaxies. Actually yes. Google image search for ...

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

  • 02:48: Before I get to what the team observed, let me describe what they expected to see.

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

  • 10:51: ... rotational energy of the black hole. It’s hypothesized that some jets observed from accreting black holes may be powered by this ...

2020-03-03: Does Quantum Immortality Save Schrödinger's Cat?

  • 13:07: It ensures that sensible and consistent macroscopic realities are observed across each branch.

2020-02-24: How Decoherence Splits The Quantum Multiverse

  • 09:18: ... some magical effect whereby the wavefunction “knows” that it has been observed and so ...

2020-02-18: Does Consciousness Influence Quantum Mechanics?

  • 11:24: You talk to each other and agree that you observed the same result - the wavefunction collapses in the same way for both of you.

2020-02-11: Are Axions Dark Matter?

  • 02:35: ... In fact they almost demand it - and yet no such violation has ever been observed. ...

2020-01-13: How To Capture Black Holes

  • 08:27: ... it may explain why so many surprisingly massive black hole mergers are observed. And if we spot more and more high-mass mergers that will be further ...

2019-12-09: The Doomsday Argument

  • 03:03: He got a value that was a factor of 10 higher than what would be observed 10 years later when dark energy was discovered.
  • 03:48: Weinberg calculated that the density of dark energy should most typically be observed to be around 5-10 times the density of matter.

2019-12-02: Is The Universe Finite?

  • 02:06: ... expansion rate for the universe that does not match the expansion rate observed today - particularly the modern expansion rate determined from supernova ...

2019-11-11: Does Life Need a Multiverse to Exist?

  • 09:49: If fact, that’s true if the strength of vacuum energy were only a little larger than is observed.

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

  • 00:57: ... strong anthropic principle tells us that an observed universe must be able to produce observers - and we’ll get to the ...
  • 13:48: And this was NOT observed in the light from a distant gamma ray burst, which presents a challenge for the theory.

2019-09-16: Could We Terraform Mars?

  • 04:06: The ablation of what is left of the Martian atmosphere has now been directly observed by NASA’s MAVEN spacecraft, as we’ve also discussed before.

2019-08-06: What Caused the Big Bang?

  • 03:04: Now, we know that something like this exists because we've observed it in the accelerating expansion produced by dark energy.

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

  • 02:51: ... points separated by an angle that is the same as the ratio between the observed wavelength and the separation of the telescopes – also called the ...
  • 03:19: ... for the resolution of any telescope – it’s the diffraction limit – the observed wavelength divided by the diameter of the ...

2019-04-24: No Dark Matter = Proof of Dark Matter?

  • 00:03: ... the effect of dark matter dark matter and baryons should never be observed separately the first piece of evidence that baryons and dark matter can ...

2019-03-28: Could the Universe End by Tearing Apart Every Atom?

  • 00:25: ... us from giving it a name we call this unknown influence dark energy. the observed acceleration is for the most part nicely described with a constant ...

2019-03-20: Is Dark Energy Getting Stronger?

  • 09:29: When compared to observed UV brightness that gives you distance.

2019-01-24: The Crisis in Cosmology

  • 03:39: ...whose observed brightness, therefore, tells us their distance.
  • 09:18: ...could give the power spectrum observed by Planck.

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

  • 00:37: ... come swooping in and shout aliens every time something inexplicable is observed and we have at least one counterpoint mark gibble says that no it's ...

2018-11-21: 'Oumuamua Is Not Aliens

  • 03:48: But no coma or tail was observed in Oumuamua.
  • 04:36: In fact, the observed acceleration seems to be following an inverse square law.
  • 05:09: ... thick and made of a highly reflective material would produce the observed brightness and ...
  • 06:59: Without reflective dust, outgassing would be invisible to our telescopes but could still cause the observed acceleration.

2018-11-14: Supersymmetric Particle Found?

  • 09:49: It may also be that there were some gigantic bursts of regular neutrinos at the time of the observed events.
  • 10:05: In fact, one of the two events may have been associated with a distant supernova that was observed around the same time and location.

2018-10-03: How to Detect Extra Dimensions

  • 00:59: The key to this breakthrough was the gravitational wave event observed in August of 2017, GW170817.
  • 01:29: The resulting kilonova is first observed in gravitational waves and then as a gamma ray burst.

2018-09-20: Quantum Gravity and the Hardest Problem in Physics

  • 00:47: Together, general relativity and quantum mechanics have allowed us to explain nearly every fundamental phenomenon observed.
  • 02:25: It describes particles as waves of infinite possibility whose observed properties are intrinsically uncertain.

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

  • 04:05: ... observed streaks on the surface of the planet that he named "canali." That's ...

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

  • 02:07: ... the Carrington Event, after British astronomer Richard Carrington who observed ...

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

  • 01:31: ... or microstates in physics-speak-- that could produce the same observed set of macroscopic observables, or the same ...

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

  • 05:46: Every neutrino we've ever observed was spotted using the weak interaction.
  • 06:33: We've observed a neutrino's flavor can change.

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

  • 00:46: In its two and a half years of operation, LIGO has observed five certain black hole-black hole mergers.
  • 01:47: Perhaps we've observed the merging of primordial black holes formed in the instant after the Big Bang.

2018-04-04: The Unruh Effect

  • 09:46: ... to directly observe Unruh particles, although analogies have been observed even in classical systems, like this really cool study with water ...

2018-03-28: The Andromeda-Milky Way Collision

  • 02:36: He observed Cepheid variables, which have a pulsation rate that depends on their energy output.
  • 04:40: Then they averaged the observed motion of all of those stars and removed the effects due to the rotation of Andromeda and the motion of the sun.

2018-01-31: Kronos: Devourer Of Worlds

  • 05:01: So why are their chemical differences much higher than ever observed for a wide binary pair?
  • 06:06: Oh et al. calculated that 15 Earth masses of raw Earth material would produce the observed abundances very nicely.

2018-01-17: Horizon Radiation

  • 12:54: These are observed as X-ray flares.

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

  • 03:25: The observed faint flash of gamma rays from exploding stars can last anywhere from a couple of seconds to a few minutes.

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

  • 00:51: ... it became abundantly clear that we were looking at the first object ever observed that came from outside our solar ...
  • 03:00: ... previously observed asteroid-- indeed, every previously observed everything in our solar ...

2017-11-22: Suicide Space Robots

  • 03:37: But then inexplicably, sporadic recoveries in power were observed.
  • 12:20: ... has a lot of trouble explaining why it produces the tiny energy density observed as dark energy, as opposed to either 0 or very high energy ...

2017-10-19: The Nature of Nothing

  • 07:40: ... the same year that the Lamb shift was first observed, German physicist Hans Bethe successfully explained it in terms of a ...
  • 09:42: Now while there are potentially other explanations for the observed force, this has been taken as strong evidence that vacuum energy is real.
  • 10:22: ... so, then the amount of vacuum energy needed to produce the observed acceleration is tiny, around one one hundred millionth of an erg per ...

2017-10-04: When Quasars Collide STJC

  • 03:59: ... short the target is observed with radio telescopes on opposite sides of the planet, and phase ...
  • 06:47: The extreme energy densities observed are also what you'd expect from the bases of two distinct jets.

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

  • 07:09: The observed gamma ray burst, GRB, was of that type.

2017-08-24: First Detection of Life

  • 03:10: A set of non-equilibrium chemical abundances must be observed that can't possibly be explained without life.
  • 04:25: While there are non-biological ways of making nitrous oxide, like lightning, these aren't nearly enough to account for the amount observed.
  • 06:06: Galileo also observed the spectrum of Earth's surface and took color photographs.
  • 08:06: The parent star was observed using the Hubble and Spitzer Space Telescopes during a transit.

2017-08-02: Dark Flow

  • 02:28: ... there must be some reference frame, some velocity, in which there's no observed Doppler shift in any ...

2017-06-21: Anti-Matter and Quantum Relativity

  • 15:28: ... greatest talents was his uncanny ability to see the fundamentals beneath observed ...

2017-06-07: Supervoids vs Colliding Universes!

  • 06:21: ... of reduction in temperature in the CMB, which is a mere 1/5 of the observed 150 microkelvin ...
  • 06:38: McKenzie et al. also observed a control region, G23, in the direction of the star [INAUDIBLE]..
  • 07:01: And that's actually a good match to the observed deviation of 15 microkelvins.

2017-01-25: Why Quasars are so Awesome

  • 03:19: Its light must have been traveling from two billion light years away to acquire the observed redshift.

2017-01-19: The Phantom Singularity

  • 15:55: A vacuum test out of TU Dresden in Germany observed a thrust, but found the thrust was the same even if they stood the EM drive vertically.

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

  • 03:41: The main criticism of all non-vacuum tests is that thermal convection in the surrounding air may have produced the observed force.
  • 04:36: The thrusts were reported to be the same as those observed in a non-vacuum.
  • 04:42: The average thrust to input power observed was around 1.2 millinewton per kilowatt.
  • 04:50: That's vastly smaller than the thrust observed by Shawyer's experiments, but still much, much larger than for a photon thruster.
  • 08:42: All of that said, if the observed effect really is a thrust, then something is causing it.

2016-11-16: Strange Stars

  • 08:00: ... all, the pulsar in the Crab Nebula was also observed as a supernova by Chinese astronomers in 1054, except something was ...

2016-11-09: Did Dark Energy Just Disappear?

  • 02:52: However, in the 18 years since the first studies, we've observed a lot more of these exploding white dwarfs.

2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers

  • 02:11: ... in topology were the culprit behind a strange quantized magnetic field observed in the mysterious "quantum hole effect." These findings will lead to ...

2016-10-26: The Many Worlds of the Quantum Multiverse

  • 02:55: And so until it's observed, it exists in a superposition of states.
  • 03:29: And what about the entire rest of the universe that's not currently being observed by physicists or cats?

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

  • 05:31: We always find that the observed quantum spin aligns itself with our chosen measurement axis.
  • 08:36: The instantaneous influence has been observed over many kilometers at this point.

2016-09-07: Is There a Fifth Fundamental Force? + Quantum Eraser Answer

  • 01:59: Well, in short, it's because the anomaly was observed for a very particular transition between the beryllium nuclear states.

2016-08-24: Should We Build a Dyson Sphere?

  • 09:43: Admittedly, the fading that the Kepler Space Telescope observed in Tabby's star is sort of consistent with a partial swarm.

2016-07-27: The Quantum Experiment that Broke Reality

  • 00:06: One of the strangest experimental results ever observed has got to be that of the single particle double-slit experiment.
  • 01:43: This double-slit interference of light was first observed by Thomas Young back in 1801.
  • 04:56: This crazy effect has even been observed with whole atoms, even whole molecules.
  • 05:02: ... are gigantic spherical molecules of 60 carbon atoms and have been observed to produce double-slit interference under special ...

2016-07-20: The Future of Gravitational Waves

  • 01:09: On December 26, LIGO again observed the merger of two different black holes.
  • 03:59: It's kind of amazing that the signals observed look exactly like what we expect them to from the predictions of general relativity.

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

  • 11:00: But this observed whiteness is a result of the fact that our color sensitivity is limited.

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

  • 08:59: ... to do this just by varying the constant until the Planck law matched the observed ...

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

  • 08:58: This ultimate gravitational lensing has not yet been observed.
  • 11:28: The idea is that a physical system doesn't have the familiar classical properties like position, momentum, spin, et cetera, until it is observed.

2016-06-01: Is Quantum Tunneling Faster than Light?

  • 00:35: Each specific state has a certain probability of being true when the object is observed.

2016-02-17: Planet X Discovered?? + Challenge Winners!

  • 04:06: To determine the observed tick rate, you also have to factor in the travel time of light.
  • 04:57: Where those paths intersect the vertical world line tells you the observed time interval between the ticks.
  • 06:20: The length of the observed second decreases by this factor for an approaching clock and increases for a receding clock.

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

  • 01:03: However, there's one last, incredible prediction that has never been directly observed-- gravitational waves.

2015-10-15: 5 REAL Possibilities for Interstellar Travel

  • 12:26: Ed Stephan asks why we're even talking about gravitational waves when none have ever been observed.

2015-09-23: Does Dark Matter BREAK Physics?

  • 01:16: From this, we can figure out exactly how much mass is needed to cause the observed lensing.
  • 04:35: But they ultimately have a hard time getting all of the observed effects.

2015-08-27: Watch THIS! (New Host + Challenge Winners)

  • 03:34: Which quasar is the most distant object ever observed?

2015-03-25: Cosmic Microwave Background Explained

  • 00:50: Problem is, we don't know of any source anywhere that would emit this observed pattern of microwave emission, so where's it coming from?
  • 02:32: The CNB is one of the closest things to a mathematically perfect thermal spectrum that has ever been observed.

2015-03-04: Should We Colonize Venus Instead of Mars?

  • 07:11: What the Hubble Bubble offers is a potential alternative to the currently observed, accelerated expansion of space.
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