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	2022-12-08: How Are Quasiparticles Different From Particles? 07:21: You can think of sound as a coherent beam of phonons, like a laser, while heat is a random buzz of phonons.
	2022-10-26: Why Did Quantum Entanglement Win the Nobel Prize in Physics? 09:11: Aspect’s setup was very similar to Clauser's, with a beam of calcium atoms excited by light - this time a laser rather than an arc lamp.
	2022-06-30: Could We Decode Alien Physics? 16:39: ... an example is something like a giant laser array pushing a light sail.   So this concern is very valid. ...
	2022-06-22: Is Interstellar Travel Impossible? 02:35: ... sails, which would be accelerated to 20% light speed by a giant array of lasers back on ... 05:35: ... of junk in the ecliptic plane - and maybe we blast a path ahead with lasers or something from ... 02:35: ... sails, which would be accelerated to 20% light speed by a giant array of lasers back on ... 05:35: ... of junk in the ecliptic plane - and maybe we blast a path ahead with lasers or something from ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 13:56: The plan is to use a giant laser array to accelerate a train of mylar light sails to 20% the speed of light in the direction of Proxima.
	2022-01-12: How To Simulate The Universe With DFT 19:27: ... real gas guzzler, so perhaps Dyson spheres are made to power light sail lasers that accelerate craft to 99.9999blahblah% the speed of light ...
	2021-10-13: New Results in Quantum Tunneling vs. The Speed of Light 11:02: In this experiment, they fired ultracold rubidium atoms at a laser field that was spread out over a small area. 11:20: ... those ones, their spins were altered by the magnetic field of the laser, and the longer they spent inside the barrier, the more their spins ... 11:02: In this experiment, they fired ultracold rubidium atoms at a laser field that was spread out over a small area.
	2021-09-21: How Electron Spin Makes Matter Possible 01:44: ... stack as many bosons on top of each other as you like. For example in a laser beam, there’s no limit to the number of photons you can add - all of ... 05:59: ... If you have two such wavefunctions overlapping - like two photons in a laser beam, a shift in one of them by half a wave cycle puts the two out of ... 01:44: ... stack as many bosons on top of each other as you like. For example in a laser beam, there’s no limit to the number of photons you can add - all of them in ... 05:59: ... If you have two such wavefunctions overlapping - like two photons in a laser beam, a shift in one of them by half a wave cycle puts the two out of phase ...
	2021-06-16: Can Space Be Infinitely Divided? 03:14: ... say you’re trying to measure the distance to an object. You shine a laser beam at   it, which reflects back to a detector that ... 03:47: ... object with a powerful short-wavelength X-ray   laser and you may get an amazing distance measure, but you’ll transfer a ... 03:14: ... say you’re trying to measure the distance to an object. You shine a laser beam at   it, which reflects back to a detector that ...
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 13:57: ... might know that regular laser light is produced when an incoming photon causes an electron in a ...
	2021-05-19: Breaking The Heisenberg Uncertainty Principle 05:01: ... Laser Interferometer Gravitational Wave Observatory measures ripples in the ... 05:36: ... Laser light is split and sent along those paths and then later recombined in ... 05:58: the recombined laser no longer perfectly cancels, and so flashes of light are observed. 06:44: ... quantum fluctuations in the phase of the laser beams are larger than the change in the arm lengths due to a ... 07:07: To improve our ability to detect faint gravitational waves we need to reduce the uncertainty in the phase of the laser beams. 07:25: ... light from a laser beam obeys the Heisenberg uncertainty principle in a very specific ... 08:35: The laser is sent through a special material called a non-linear crystal, which converts incoming photons into pairs of photons. 09:26: ... with more uncertainty in the number of photons traveling in your laser ... 07:25: ... light from a laser beam obeys the Heisenberg uncertainty principle in a very specific way—it has ... 09:26: ... with more uncertainty in the number of photons traveling in your laser beam. ... 07:25: ... light from a laser beam obeys the Heisenberg uncertainty principle in a very specific way—it has equal ... 05:36: ... later recombined in such a way that the electromagnetic waves of these laser beams destructively ... 06:44: ... quantum fluctuations in the phase of the laser beams are larger than the change in the arm lengths due to a gravitational ... 07:07: To improve our ability to detect faint gravitational waves we need to reduce the uncertainty in the phase of the laser beams. 05:36: ... later recombined in such a way that the electromagnetic waves of these laser beams destructively ... 05:01: ... Laser Interferometer Gravitational Wave Observatory measures ripples in the fabric of space ... 05:36: ... Laser light is split and sent along those paths and then later recombined in such a ...
	2021-03-23: 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. 06:25: ... the electron is in state 1 when the laser pulse hits, it absorbs a laser photon and jumps to 3, and then ... 06:47: But what if the laser hits while the electron is in the middle of a transition - in a superposition of states 1 and 2? 07:02: ... to the researchers, the laser acts like a measurement - and remember, measurement should be able to ... 07:15: To test this, the researchers start the atoms all in state one, and then hit them with a series of very rapid laser pulses. 08:41: In this case, hitting the atoms with a laser pulse. 09:11: ... showed that each laser photon perturbed the system in such a way that the electron had an ... 07:02: ... to the researchers, the laser acts like a measurement - and remember, measurement should be able to freeze ... 06:47: But what if the laser hits while the electron is in the middle of a transition - in a superposition of states 1 and 2? 06:25: ... the electron is in state 1 when the laser pulse hits, it absorbs a laser photon and jumps to 3, and then immediately drop back down to 1, releasing the ... 09:11: ... showed that each laser photon perturbed the system in such a way that the electron had an increased ... 06:25: ... the electron is in state 1 when the laser pulse hits, it absorbs a laser photon and jumps to 3, and then immediately ... 08:41: In this case, hitting the atoms with a laser pulse. 06:25: ... the electron is in state 1 when the laser pulse hits, it absorbs a laser photon and jumps to 3, and then immediately drop back ... 07:15: To test this, the researchers start the atoms all in state one, and then hit them with a series of very rapid laser pulses. 05:55: To recap - we have a collection of laser-cooled atoms in an electromagnetic trap.
	2021-03-09: How Does Gravity Affect Light? 02:39: A spider breaks through the front hull and you fire your laser at it. 02:49: The spider still observes the laser traveling at the speed of light - because the speed of light is invariant to all observers. 03:04: ... the front peak of your laser pulse reaches the spider the ship continues to accelerate - which means ... 03:22: Your laser’s power rating goes from kill to tickle - good news for the giant alien spider, not so much for you. 05:19: This time you fire your laser across the deck perpendicular to the direction of acceleration. 03:04: ... the front peak of your laser pulse reaches the spider the ship continues to accelerate - which means the ... 02:49: The spider still observes the laser traveling at the speed of light - because the speed of light is invariant to all observers. 03:22: Your laser’s power rating goes from kill to tickle - good news for the giant alien spider, not so much for you.
	2021-02-17: Gravitational Wave Background Discovered? 00:00: ... element of space itself the gravitational wave background when the laser interferometer gravitational wave observatory ligo turned on in 2015 it ...
	2021-01-19: Can We Break the Universe? 00:02: Black holes, gravitational waves, he was even the first to realize that friggin lasers could be a thing.
	2021-01-12: What Happens During a Quantum Jump? 06:16: By the 80s we’d learned how to trap and cool a single atom with lasers. 06:28: ... single atom - in this case mercury or barium - is bathed in a laser beam with a frequency exactly tuned to the energy difference between two ... 06:41: If the electron is in level 1, it should jump to level 2 by absorbing a photon from the laser light. 07:33: So, we have our atom happily fluorescing in the original laser beam. 07:37: Now flash a second laser with frequency tuned to take the electron from level 1 to level 3. 09:09: They then placed these artificial atoms inside a microwave cavity - analogous to the laser, which could cause the “atom” to transition between states. 06:28: ... single 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 ... 07:33: So, we have our atom happily fluorescing in the original laser beam. 06:41: If the electron is in level 1, it should jump to level 2 by absorbing a photon from the laser light. 06:16: By the 80s we’d learned how to trap and cool a single atom with lasers.
	2020-07-20: The Boundary Between Black Holes & Neutron Stars 02:13: A laser beam is split, sent down these tubes, then recombined. 02:18: ... in these arm lengths, which in turn causes the peaks and valleys of the laser’s electromagnetic wave to line up differently, and so those changes can be ... 02:13: A laser beam is split, sent down these tubes, then recombined. 02:18: ... in these arm lengths, which in turn causes the peaks and valleys of the laser’s electromagnetic wave to line up differently, and so those changes can be ...
	2020-07-08: Does Antimatter Explain Why There's Something Rather Than Nothing? 09:19: ... energies between the various positron orbitals in the anti-atoms using laser spectroscopy. The exact energy of one of these states is determined by ...
	2020-06-22: Building Black Holes in a Lab 09:19: ... done experiments with super-cold rubidium gas in a BEC state. Using a laser, it’s possible to effectively create a flow within the ... 09:59: When the laser pushes on the gas, the rubidium atoms want to move out of the way of the beam. 10:04: Here, the edge of the laser acts as the event horizon—the rubidium atoms don’t have enough energy to jump back up over the waterfall. 11:04: ... pointed to experimental observations of analog Hawking radiation—in laser pulses, fluids, and BECs—as proof-positive of Hawking radiation in black ... 10:04: Here, the edge of the laser acts as the event horizon—the rubidium atoms don’t have enough energy to jump back up over the waterfall. 11:04: ... pointed to experimental observations of analog Hawking radiation—in laser pulses, fluids, and BECs—as proof-positive of Hawking radiation in black ... 09:59: When the laser pushes on the gas, the rubidium atoms want to move out of the way of the beam.
	2020-05-18: Mapping the Multiverse 15:40: ... has been performed with much higher precision using other methods - lasers, vacuum chambers, strange quantum mechanical states of light - you name ...
	2020-02-24: How Decoherence Splits The Quantum Multiverse 03:29: Laser light is an example of a coherent wave.
	2020-01-13: How To Capture Black Holes 00:24: ... September 2015 the laser interferometer gravitational wave observatory - LIGO - detected its ...
	2019-12-02: Is The Universe Finite? 13:33: ... speculative, and philosophical stuff over a beer, and some who are laser focused on their own field and don't really think far beyond ...
	2019-07-15: The Quantum Internet 03:19: We can already send photons of light very long distances using lasers or fiber optics - and those photons are pretty quantum. 10:22: So the current state of the art is that entangled quantum states have been transmitted with photons using fibre optics and lasers. 03:19: We can already send photons of light very long distances using lasers or fiber optics - and those photons are pretty quantum. 10:22: So the current state of the art is that entangled quantum states have been transmitted with photons using fibre optics and lasers.
	2019-06-20: The Quasar from The Beginning of Time 04:20: ... in real time, Gemini creates its own artificial guide star by shooting lasers to twinkle off sodium atoms at 90km height, right off the edge of ...
	2018-08-30: Is There Life on Mars? 07:31: ... 1996 with the advent of high-resolution scanning electron microscopy and laser mass ...
	2018-04-18: Using Stars to See Gravitational Waves 00:31: We've already talked about the Laser Interferometer Gravitational-Wave Observatory, LIGO, and the first discovery of gravitational waves here. 04:08: That's LISA, the Laser Interferometer Space Antenna. 00:31: We've already talked about the Laser Interferometer Gravitational-Wave Observatory, LIGO, and the first discovery of gravitational waves here. 04:08: That's LISA, the Laser Interferometer Space Antenna. 00:31: We've already talked about the Laser Interferometer Gravitational-Wave Observatory, LIGO, and the first discovery of gravitational waves here. 04:08: That's LISA, the Laser Interferometer Space Antenna.
	2017-10-11: Absolute Cold 01:00: Using lasers and magnetic fields, we've now managed to cool certain substances to less than a billionth of a Kelvin.
	2017-09-20: The Future of Space Telescopes 08:58: A laser can find a glitter cloud, if you will. 09:01: ... would be fractions of a millimeter in size, small enough that commercial lasers could corral and shape the particles into an effective mirror or ...
	2017-09-13: Neutron Stars Collide in New LIGO Signal? 00:37: ... the Laser Interferometer Gravitational Wave Observatory, LIGO, detected ...
	2017-07-19: The Real Star Wars 04:28: It included much-expanded surface launch anti-ballistic missile ABM networks, but also, get this, an atomic bomb-powered x-ray laser satellite. 04:50: A quick review on lasers. 05:22: X-ray lasers were seen as extremely promising in missile defense because they can completely vaporize metal. 05:31: But in the vacuum of space, these lasers can have ranges of many hundreds, even thousands of kilometers. 05:37: Now, normal lasers bounce the beam back and forth through a gain median to build up power. 05:45: So a powerful x-ray laser needs to start with a powerful x-ray source. 05:50: For Excalibur, that source was a nuclear bomb set off behind an array of laser tubes. 06:00: One blast is enough to pass several dozen x-ray lasers, and each of those can take out an ICBM. 06:32: One, it was never clear whether any of the 10 underground test detonations produced anything near the promised laser amplification. 07:41: So non-nuke powered lasers, and also the potentially very deadly kinetic impact weapons. 10:08: ... super-villains, the USSR also played around with powerful ground based lasers, which supposedly blinded some US spy satellites, and particle beams, ... 10:24: ... full-fledged orbiting the battle station that would have had a megawatt laser designed to take out the as-yet unlaunched US anti-missile ... 06:32: One, it was never clear whether any of the 10 underground test detonations produced anything near the promised laser amplification. 10:24: ... full-fledged orbiting the battle station that would have had a megawatt laser designed to take out the as-yet unlaunched US anti-missile ... 04:28: It included much-expanded surface launch anti-ballistic missile ABM networks, but also, get this, an atomic bomb-powered x-ray laser satellite. 05:50: For Excalibur, that source was a nuclear bomb set off behind an array of laser tubes. 04:50: A quick review on lasers. 05:22: X-ray lasers were seen as extremely promising in missile defense because they can completely vaporize metal. 05:31: But in the vacuum of space, these lasers can have ranges of many hundreds, even thousands of kilometers. 05:37: Now, normal lasers bounce the beam back and forth through a gain median to build up power. 06:00: One blast is enough to pass several dozen x-ray lasers, and each of those can take out an ICBM. 07:41: So non-nuke powered lasers, and also the potentially very deadly kinetic impact weapons. 10:08: ... super-villains, the USSR also played around with powerful ground based lasers, which supposedly blinded some US spy satellites, and particle beams, ... 05:37: Now, normal lasers bounce the beam back and forth through a gain median to build up power.
	2017-03-15: Time Crystals! 04:32: Now cause those spins to flip back and forth using a laser. 04:36: A laser is just a very well-ordered electromagnetic wave with a known period or frequency. 04:43: The spin-flip oscillation will be determined by the period of the laser. 04:48: That laser is what takes the system out of equilibrium, because you are basically pumping in energy. 04:54: Causing spins to flip in a laser isn't particularly exciting. 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 input EM field is ... 05:19: ... theorized that spins should not oscillate at the same period as the laser, but at an integer multiple of the driving ... 05:29: So two, three, four, et cetera spin oscillations for every EM field oscillation in the laser. 06:54: ... up a chain of ions, linking 10 ytterbium ions and driving them with a laser. ... 07:23: The ytterbium ions oscillations were twice the laser period. 04:54: Causing spins to flip in a laser isn't particularly exciting. 07:23: The ytterbium ions oscillations were twice the laser period.
	2017-02-15: Telescopes of Tomorrow 06:53: ... track this turbulence in real time, GMT will shine six powerful sodium lasers 90 kilometers into the upper atmosphere, where their light will produce ...
	2017-01-11: The EM Drive: Fact or Fantasy? 12:36: Mr. Rich suggests that lasers and even grasers, gamma ray lasers, are much more efficient for targeted long-distance communication. 12:46: There are even plans to use lasers to communicate between the hopefully upcoming Starshot Shot light sail mission to Alpha Centauri. 12:54: But as Gareth Dean points out, lasers suck for broadcast, so sending a signal broadly. 12:36: Mr. Rich suggests that lasers and even grasers, gamma ray lasers, are much more efficient for targeted long-distance communication. 12:46: There are even plans to use lasers to communicate between the hopefully upcoming Starshot Shot light sail mission to Alpha Centauri. 12:54: But as Gareth Dean points out, lasers suck for broadcast, so sending a signal broadly.
	2016-08-24: Should We Build a Dyson Sphere? 04:13: It would reflect light into a small solar power plant that would then beam energy somewhere useful, perhaps with a laser or a maser.
	2016-07-27: The Quantum Experiment that Broke Reality 06:24: ... starts its journey wherever we put the laser or electron gun or buckyball trebuchet and it releases its energy at a ...
	2016-07-20: The Future of Gravitational Waves 00:14: ... September 14, 2015, the Laser Interferometer Gravitational Wave Observatory, LIGO, detected the ...
	2016-06-01: Is Quantum Tunneling Faster than Light? 05:42: Laser beams are sent down paths at right angles and then brought back together. 06:00: We want to send individual photons instead of lasers. 05:42: Laser beams are sent down paths at right angles and then brought back together. 06:00: We want to send individual photons instead of lasers.
	2016-05-18: Anti-gravity and the True Nature of Dark Energy 12:09: Well, the idea is to beam the data back with low-power lasers, or perhaps alternatively to use the sail itself as an antenna for radio transmission. 12:27: If the signal sent by laser, then the same phased array that projects the launched laser will also be able to spot the returning later signal. 12:48: The impulse generated by the laser is many orders of magnitude greater than that of the star at the other end. 13:34: The analogies to Moore's Law for laser power, material science, battery tech, et cetera, are also alive and well. 12:09: Well, the idea is to beam the data back with low-power lasers, or perhaps alternatively to use the sail itself as an antenna for radio transmission.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 01:31: A spacecraft is propelled as the light from the sun-- or from a giant laser-- accelerates a sail of reflective material. 01:57: Light sails need no onboard propellant and the power generation stays back at home, whether it's the sun or an Earth-based laser. 02:51: The solution is lasers. 02:54: The solution is so often lasers. 03:06: ... be a kilometers-wide carbon fiber mesh sail propelled by a microwave laser-- a maser, which would be focused by a 1,000 kilometer diameter microwave ... 03:33: The basic concept is the same-- an extremely low mass laser powered light sail. 04:09: ... and would include multiple detectors, including a camera, small lasers that work both as thrusters and as communication devices, and perhaps ... 04:24: Another big difference compared to Starwisp is that Starshot will be powered by a visible light laser, not a maser. 04:31: This is important because visible light lasers can maintain a much tighter beam than a maser can. 04:41: The ultra low mass means that the nanocraft can be accelerated to a decent clip with a giant laser that we could plausibly build in a generation. 04:51: So less vast alien mega structure slash planet destroyer and more Bond super-villain laser. 04:58: It would be a ground-based phased array of mini lasers called a light beamer that will produce a combined 100 gigawatt beam. 05:23: Build a laser that big and you want to use it, right? 06:32: The laser propulsion array needs to combine and direct its beams with incredible precision through a turbulent atmosphere. 07:00: It's assumed that processor size, camera pixel density, laser power to mass ratio, et cetera will continue their exponential improvement. 01:31: A spacecraft is propelled as the light from the sun-- or from a giant laser-- accelerates a sail of reflective material. 07:00: It's assumed that processor size, camera pixel density, laser power to mass ratio, et cetera will continue their exponential improvement. 03:33: The basic concept is the same-- an extremely low mass laser powered light sail. 06:32: The laser propulsion array needs to combine and direct its beams with incredible precision through a turbulent atmosphere. 02:51: The solution is lasers. 02:54: The solution is so often lasers. 04:09: ... and would include multiple detectors, including a camera, small lasers that work both as thrusters and as communication devices, and perhaps ... 04:31: This is important because visible light lasers can maintain a much tighter beam than a maser can. 04:58: It would be a ground-based phased array of mini lasers called a light beamer that will produce a combined 100 gigawatt beam.
	2016-02-11: LIGO's First Detection of Gravitational Waves! 00:37: On September 18, the Laser Interferometer Gravitational-Wave Observatory switched back on after three years of upgrades. 06:35: ... upcoming Evolved Laser Interferometer Space Antenna-- eLISA-- will see an entirely different ... 00:37: On September 18, the Laser Interferometer Gravitational-Wave Observatory switched back on after three years of upgrades. 06:35: ... upcoming Evolved Laser Interferometer Space Antenna-- eLISA-- will see an entirely different part of this ... 00:37: On September 18, the Laser Interferometer Gravitational-Wave Observatory switched back on after three years of upgrades. 06:35: ... upcoming Evolved Laser Interferometer Space Antenna-- eLISA-- will see an entirely different part of this spectrum, ...
	2015-10-28: Is The Alcubierre Warp Drive Possible? 07:25: LISA is amazing, although now it's ELISA, the Evolved Laser Interferometer Space Antenna.
	2015-10-22: Have Gravitational Waves Been Discovered?!? 05:01: With lasers, of course-- in fact, with a giant Michelson interferometer. 05:07: This is the LIGO experiment, and it goes something like this-- shoot a laser beam. 05:01: With lasers, of course-- in fact, with a giant Michelson interferometer.
	2015-10-15: 5 REAL Possibilities for Interstellar Travel 06:13: ... kilometer wide sapphire coated sail, riding the beam of a gigantic space laser blasting the power equivalent of 100 nuclear ... 06:44: ... we're going to need to a bigger boat, which means a proper visible light laser and a larger sail, coated with advanced, reflective and heat resistant ... 06:55: ... laser is going to have to be ridiculously large, possibly built on the moon ... 07:07: Because we aren't carrying any fuel, maximum speed is only limited by the power and collamation of our laser and the size of our sail. 07:56: ... sufficient energy density of laser light focused in a small enough region would bend the fabric of space ... 09:04: The only drawback is that the lasers creating the black hole would need to be vastly more powerful than even the black hole they created. 06:13: ... kilometer wide sapphire coated sail, riding the beam of a gigantic space laser blasting the power equivalent of 100 nuclear ... 07:56: ... sufficient energy density of laser light focused in a small enough region would bend the fabric of space time ... 09:04: The only drawback is that the lasers creating the black hole would need to be vastly more powerful than even the black hole they created.
	2015-08-19: Do Events Inside Black Holes Happen? 07:57: A laser pointer carried by the monkey never enters the black hole, as far as we're concerned. 08:02: Because of time dilation, we would detect any laser pulse that the monkey sends with a lower frequency, i.e. 07:57: A laser pointer carried by the monkey never enters the black hole, as far as we're concerned. 08:02: Because of time dilation, we would detect any laser pulse that the monkey sends with a lower frequency, i.e.
	2015-07-29: General Relativity & Curved Spacetime Explained! 05:37: Fire a laser pulse from the ground floor of a building up to a photon detector on the roof.
	2015-07-15: Can You Trust Your Eyes in Spacetime? 02:51: And at that same moment, I shoot a photon from a laser pointer to the right.
	2015-06-24: The Calendar, Australia & White Christmas 06:32: However, they might be using optical laser pulses if they have limited resources or the kind of alien billboards that we discussed in the episode.
	2015-06-17: How to Signal Aliens 02:14: So let's move on to method two, lasers. 02:17: Nowadays, lasers can produce high-power ultra-short pulses that can outshine the sun for less than a nanosecond. 02:23: Nothing natural pulses with stellar brightness for a nanosecond at a time, so laser pulses would look distinctly artificial to our Vulcan friends. 02:40: Attenuation from interstellar dust makes the range for optical lasers less than that for microwave beacons. 02:48: But at those distances, a laser's spot size would only grow to around the size of Jupiter's orbit. 02:58: With a lot of lasers, you could even flash several star systems per second, re-aim, and repeat over and over. 04:59: ... like the lasers, billboard transits could only be seen within a few light years of earth ... 05:55: ... besides looking for radio signals and laser pulses, which SETI does now, should SETI also be looking for geometric ... 02:23: Nothing natural pulses with stellar brightness for a nanosecond at a time, so laser pulses would look distinctly artificial to our Vulcan friends. 05:55: ... besides looking for radio signals and laser pulses, which SETI does now, should SETI also be looking for geometric alien ... 02:14: So let's move on to method two, lasers. 02:17: Nowadays, lasers can produce high-power ultra-short pulses that can outshine the sun for less than a nanosecond. 02:40: Attenuation from interstellar dust makes the range for optical lasers less than that for microwave beacons. 02:48: But at those distances, a laser's spot size would only grow to around the size of Jupiter's orbit. 02:58: With a lot of lasers, you could even flash several star systems per second, re-aim, and repeat over and over. 04:59: ... like the lasers, billboard transits could only be seen within a few light years of earth ... 02:48: But at those distances, a laser's spot size would only grow to around the size of Jupiter's orbit.
	2015-05-13: 9 NASA Technologies Shaping YOUR Future 05:18: Answer, infrared laser strobe lights connected to a video camera. 05:27: ... timing the return time of the laser pulse echos and using image rendering software, NASA funded researchers ... 05:18: Answer, infrared laser strobe lights connected to a video camera.
	2015-03-18: Can A Starfox Barrel Roll Work In Space? 00:19: Ships that bob and weave, laser cannons galore, and giant explosions all make for good drama but bad physics.

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