@Jipzorowns p=h/lambda only tells you the momentum of a photon based on wavelength and the planck constant, this equation has noting to do with it. The 'package' thing is a metaphor.
@RasmusLastname No. When we say "a quantum of energy," it's the same as when we say "a packet of light", see? It just means a little bundle of the stuff.
In fact, the greater the energy of the light, the greater the frequency of the light. Need proof? Handheld lasers. Red light has a greater wavelength (and so less energy) than green light, and same for green light and blue light; hence why red lasers aren't as dangerous as green lasers, and why green lasers cost more.
@wreynolds1995 "In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction" (Wikipedia) So, since they're all photons, shouldn't the quantum of light always be a specific energy level? I'm not saying you're wrong, I know you're right, I'm just trying to understand it better. It would be really helpful if you could answer ^^
@RasmusLastname Hmm. I think I know where this confusion is, and I'll admit I'm partly at fault.
Out of interest, where (or, if it's in the video, when) did you get this idea of a "quantum of energy"? Was it an exact quote or did you paraphrase someone?
BTW just so you know they are trolling Americans at the end calling them ignorant by saying that Americans call flashlights torches....the more you know.
Usually I have great admiration for the sixtysymbols videos. But the explanation of Rayleigh scattering at 5:30 makes no sense.
The wavelengths from red down to blue are all much larger than the size of a molecule. In all cases the molecules 'experiences' an effectively uniform electromagnetic field, oscillating very rapidly. It is easy to show that this gives rise to the famous 1/lambda^4 spectrum of Rayleigh scattering.
@materiasacra maybe she is just saying that the short wavelength of the blue light is more likely to hit a molecule and be scattered? i have no clue as i have little to no scientific experience
@wvb93 Thanks for your response. Yes, that is what she is saying, and it is wrong. It works as a mental image as long as you don't look at the actual scattering mechanism, and just look from a distance and see light bouncing in different directions. Molecules are 3 orders of magnitude smaller than the wavelength of the light. So the molecules 'feel' the light as an almost uniform field that oscillates rapidly. This shakes the outer electrons, which in turn emit so-called dipole radiation.
@wvb93 Yes. Because the field is (almost) uniform over the molecule, the dipole field is proportional to the volume of the molecule, i.e. to the third power of its linear size. The intensity of light is proportional to the square of the field strength, so to the sixth power of the molecular size. There are only two lengths relevant: molecular size and wavelength, so the scattering mechanism can only depend on their RATIO. (If molecule and wave would be magnified by a common factor, ...
@materiasacra ... nothing would change.) So the intensity of the scattered light, relative to the incoming light, is inversely proportional to the sixth power of the wavelength. Now we have to take into account that the scattered light spreads out in all directions (not equally in all directions!). Observing it at a distance r, it spreads over a sphere with area prop. to r^2. By the ratio-argument this gives us a factor of (lambda/r)^2 where lambda is the wavelength. Therefore ....
@materiasacra ... the observed intensity of the scattered light is propotional to lambda^-6 * lambda^2 = lambda^-4 i.e. de inverse fourth power of the wavelength. This explains the blue sky. The wavelength of blue light (say 400nm) is roughly twivce as short as that of (very deeply) red light (800nm). So the intensity of the scattered blue light is 2^4 = 16 times as much as that of red.
This reasoning applies only to particles much smaller than the wavelength (like molecules).
@OOmdebah "Can I get more information on that demonstration? What was the solution? Is it a colloid?"
I think I have seen it done across a glass of milk! - but I don't think it was milk here, although maybe diluted milk would work in a long tube like that one.
When I was 20 I knew intuitively that time is not part of space. It took me 32 years to understand rationally that according to mathematical formalism X4 = ict time is numerical order of photon motion in 4D space.
An interesting biological sidelight: our eyes see in three colors: magenta, green and green-yellow - that is all. The colors below yellow-green are determined by a calculation done by the brain based on the magnitude of the eye-yellow-green and the difference between that and the eye-green. Blue is eye-magenta without any eye-green, magenta is eye-magenta with some eye-green in it.. The brain is indeed, a weird and wonderful instrument.
... The traditional colors of red, green and blue aren't basic; they're derived by complex calculations the brain does over it's entire multi-megapixel "screen" at rates too high to detect, probably (I'd guess) by massive parallelization of the computations done in analog (of course).
Wow! photons can move a space ship with a giant sale? How can they do that if they don't any have any mass? Excellent video as usual! please keep posting them!
@cristianfcao: They have no rest mass (that is, mass of their own, that can be measured at rest). But when they are moving at the SoL (which they always are) they have energy, and according to E = mc^2, they also have a relativistic mass. With mass and velocity, they have momentum, and that momentum is to some extent transferred when the photon is reflected or absorbed.
So does that mean that there is less atmosphere in certain parts of the world wince the sky is different colours at the same time of day, for example the grey skies in England and the blue skies in Australia, or is that due to man-made output?
@VeryOxygen: Yes. The skies over Vail, Colorado are famous for their deep blue color caused by the elevation of the town at 11,500' (that's 3500 meters for those unaccustomed to the queen's system). Photographers flock there to take pictures of the Maroon Bells against that sky.
The gray skies anywhere are due to poor weather. Perhaps you noticed.
Taking pity, I direct those who cannot see the blue from their vantage point to here: shutterstockDOTcom/pic-8332879/stock-photo-the-maroon-bells-in-the-white-river-national-forest-of-colorado.html
Why is it that we still see blue or any other color on the earth that had been scattered by the atmosphere? Is it that only a portion of those photons with those wavelengths are scattered by hitting atoms and everything else is making it successfully without being disturbed?
@xeroaxlvx: Let's say that the shorter wavelength part of the visible spectrum is preferentially scattered. At noon, the sunlight is white (all colors); it still has a large proportion of the blue light that it started with, and yet, not all of it; looking at the sky off to the side, some blue light is careening off an oxygen molecule and smacking your eye. As the atmospheric path lengthens (as near sundown), more blue is scattered, leaving the redder components to blaze in the sunset.
@pauldve: No - the sun would be yellower; the sky would be paler blue, due to more of the green (and maybe even some red) being scattered by the thicker atmosphere. Eventually you would get a uniform gray, where all light is being reflected, likely many times.
I don't understand, Photons have no mass nor are they real particles.. how could we hypothetically make a solar sail or compare photons to a cricket ball without mass?
@Moviemann345 Photons ARE real particles, although there are such things as virtual photons. The reason we can compare the photon to the cricket ball is that it isn't the mass which move stuff in a collision, it's the transfer of energy.
@Juxtaroberto: Well, technically, transfer of momentum. Photons are created running at the SoL and have energy. According Einstein they therefore have a "relativistic" mass, and where there is velocity and mass there is momentum. With momentum they can push.
when u sit in an airplane, and it makes a turn, just look into the sky, looks a little bit creepy, like ur close to space, very dark...such impressive
what about dawn? the light has to go through a layer of atmosphere just as thick as during dusk... but it doesnt look redish; it looks rather light blue.
Why? does it have anything to do with doppler effect?
Sunrise and sunset look the same - red. The only thing I can think of is maybe the direction you see sunrise from has high objects in it, blocking the full view.
@donguateque: No; the sun looks reddish (if there is high humidity, dust or smoke) or yellow if there is clear air; it's the sky that is blue. There is essentially zero velocity difference between earth and the sun along their common axis, so no doppler (OK, there is a little from the Earth's spin, but it's minor; a mere 1300 km/hr or so, max).
So, blue gets scattered and all other colors go through and as a result we see blue skies. But during sunset only red and orange go through the rest get scattered and we see red and orange??
At sunset, light has to travel through a thicker atmosphere than at noon. So by the time the light hits our eyes, almost all of the blue light has been absorbed and scattered out.
@ttsodd: Look, pure sunlight before it enters the atmosphere is white (with a very slight emphasis on the yellow). Things in the atmosphere, gas molecules, dust, smoke and humidity) all preferentially scatter blue and let the red and yellow through. As the smoke, etc get thicker, the effect reaches from the blue into the green, maybe even into the yellow, scattering them all and leaving the orange and red to shine through. Look at the sun through a forest fire's smoke, and you'll get blood red.
... When you look directly into the sun (protection for your eyes, please) you get what passes through unscattered. When you look at the sky, you get the scattered colors.
Will you be doing another gamma video on the Lorentz factor? I've been looking into special relativity quite a bit lately and it would be cool to see a video on all of the weird and wonderful things that happen to things that move quickly, like Lorentz contraction and time dilation, etc.
Good question. First I imagined that Photons had very little mass, but after a quick googling I found wikipedia's article on Invariant Mass. I'm not a physicist, so I would appreciate an explanation for the layman.
using einstein's famous energy equation and adding the relativistic momentum term (giving the general energy expression):
E^2 = (m^2) x (c^4) + (p^2) x (c^2)
E is energy, m is rest mass, p is momentum, c is speed of light. photons have zero mass so E = pc. the E of photons exist in distinct packets that only depend on the frequency, f (or wavelength) (the photoelectric effect)... E=hv, h is plancks constant.
@Kev888It's a rule in relativistic physics that any particle with no rest mass can only exist moving at the speed of light. Thus the photon, and (some physicists think) the neutrino. OTOH, any particle with rest mass can only approach the speed of light.
@puncheex Of course photons travel faster than the speed of light, from their point of view. As, at the speed of light, time doesn't pass for them, they move instantly, across the universe.
I have always wanted to know why the sky is blue. Before I saw this I thought it was because of the presence of minute traces of cobalt. Now I know...
Most of the photon-related stuff you guys talk about have good classical (wave-like) or semiclassical (sort of wave-like) explanations. For instance, why the sky is blue.
You should've talked to a quantum optician! For instance, observing double slit interference one photon at a time is a remarkable demonstration of truly quantum mechanical photonic behaviour!
No what we should do is make it black. Make the lights black, the buttons black, the walls black, the carpets black, even the padding under the carpet should be black :) And I'm sure somebody will read this and excitedly type away at what the reference is. And to those people I have this to say "You big nerds" :)
Very fitting reference. A great mind from England, on a video from a university from the UK, and it's a bit more fitting as I just watched the movie last night after reading the book two semesters ago. I pride myself on being a "big nerd". I hope I actually got the reference...
@harryh111111: You seek a General Products #4 hull. Completely indestructible, transparent to all energy below UV, one single piece sphere 1000' in diameter. See wordiqDOTcom/definition/General_Products_%28Larry_Niven%29
Which equation tells you that a photon comes in 'packages'? p = h / lambda ?
Jipzorowns 1 week ago
@Jipzorowns p=h/lambda only tells you the momentum of a photon based on wavelength and the planck constant, this equation has noting to do with it. The 'package' thing is a metaphor.
ThePurpleIsland 1 week ago
Ok, that's what I thought though, thnx! :)
Jipzorowns 1 week ago
that lady at the end has no idea what shes talking about
the sky is blue really??? its obviosly green
(and thts when i realized i was colored blind
elflordbob1 2 weeks ago
lol "for all us english speakers" good one sixty symbols!
wabs05 1 month ago
If a photon is a quantum of energy how can they have different energy values? Isn't quantum sort of a minimum value?
RasmusLastname 1 month ago
@RasmusLastname No. When we say "a quantum of energy," it's the same as when we say "a packet of light", see? It just means a little bundle of the stuff.
In fact, the greater the energy of the light, the greater the frequency of the light. Need proof? Handheld lasers. Red light has a greater wavelength (and so less energy) than green light, and same for green light and blue light; hence why red lasers aren't as dangerous as green lasers, and why green lasers cost more.
wreynolds1995 1 month ago
@wreynolds1995 "In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction" (Wikipedia) So, since they're all photons, shouldn't the quantum of light always be a specific energy level? I'm not saying you're wrong, I know you're right, I'm just trying to understand it better. It would be really helpful if you could answer ^^
RasmusLastname 1 month ago
@RasmusLastname Hmm. I think I know where this confusion is, and I'll admit I'm partly at fault.
Out of interest, where (or, if it's in the video, when) did you get this idea of a "quantum of energy"? Was it an exact quote or did you paraphrase someone?
wreynolds1995 1 month ago
this one was really boring for me until learning about the why the sky is blue
Tatlreach 2 months ago
Wait... if photons are particles, why don't you get a recoil force from, say, switching on a flashlight?
UmlautBanana 2 months ago
@UmlautBanana actually you do i think. it's just infintesimally small you don't really feel anything.
RustlessPotato 2 months ago
@UmlautBanana you do,you can easily calculate that
Matzes 1 day ago
The woman's voice hurts my ears.
QQonmyPP 3 months ago
BTW just so you know they are trolling Americans at the end calling them ignorant by saying that Americans call flashlights torches....the more you know.
QQonmyPP 3 months ago
Comment removed
stagedive516 3 months ago
@QQonmyPP
No, she's from the US so she accidentally called it a flashlight, and he corrected her for the UK viewers who call it a torch.
stagedive516 3 months ago
@kristijan0kroflin
Not sure if trolling, or just stupid. =.=
TheThirdZander 4 months ago
Usually I have great admiration for the sixtysymbols videos. But the explanation of Rayleigh scattering at 5:30 makes no sense.
The wavelengths from red down to blue are all much larger than the size of a molecule. In all cases the molecules 'experiences' an effectively uniform electromagnetic field, oscillating very rapidly. It is easy to show that this gives rise to the famous 1/lambda^4 spectrum of Rayleigh scattering.
materiasacra 8 months ago
@materiasacra maybe she is just saying that the short wavelength of the blue light is more likely to hit a molecule and be scattered? i have no clue as i have little to no scientific experience
wvb93 1 month ago
@wvb93 Thanks for your response. Yes, that is what she is saying, and it is wrong. It works as a mental image as long as you don't look at the actual scattering mechanism, and just look from a distance and see light bouncing in different directions. Molecules are 3 orders of magnitude smaller than the wavelength of the light. So the molecules 'feel' the light as an almost uniform field that oscillates rapidly. This shakes the outer electrons, which in turn emit so-called dipole radiation.
materiasacra 1 month ago
@materiasacra so then is that dipole radiation responsible for the making the sky look blue?
wvb93 1 month ago
@wvb93 Yes. Because the field is (almost) uniform over the molecule, the dipole field is proportional to the volume of the molecule, i.e. to the third power of its linear size. The intensity of light is proportional to the square of the field strength, so to the sixth power of the molecular size. There are only two lengths relevant: molecular size and wavelength, so the scattering mechanism can only depend on their RATIO. (If molecule and wave would be magnified by a common factor, ...
materiasacra 1 month ago
@materiasacra ... nothing would change.) So the intensity of the scattered light, relative to the incoming light, is inversely proportional to the sixth power of the wavelength. Now we have to take into account that the scattered light spreads out in all directions (not equally in all directions!). Observing it at a distance r, it spreads over a sphere with area prop. to r^2. By the ratio-argument this gives us a factor of (lambda/r)^2 where lambda is the wavelength. Therefore ....
materiasacra 1 month ago
@materiasacra ... the observed intensity of the scattered light is propotional to lambda^-6 * lambda^2 = lambda^-4 i.e. de inverse fourth power of the wavelength. This explains the blue sky. The wavelength of blue light (say 400nm) is roughly twivce as short as that of (very deeply) red light (800nm). So the intensity of the scattered blue light is 2^4 = 16 times as much as that of red.
This reasoning applies only to particles much smaller than the wavelength (like molecules).
materiasacra 1 month ago
@materiasacra thanks for that!
wvb93 1 month ago
@dinmorerengeit
No to emit light you need photons
josyula547 9 months ago
Does every lightsource emit photons?
for example a light bulb.. or do you need fusion to emit photons?
dinmorerengeit 9 months ago
Reflection underlies scattering
mrrn100 10 months ago
This has been flagged as spam show
Wow. I like Photons now. I think Turtles are neat too.
silentonall 10 months ago
Can I get more information on that demonstration? What was the solution? Is it a colloid?
OOmdebah 11 months ago
This has been flagged as spam show
@OOmdebah "Can I get more information on that demonstration? What was the solution? Is it a colloid?"
I think I have seen it done across a glass of milk! - but I don't think it was milk here, although maybe diluted milk would work in a long tube like that one.
chrisofnottingham 9 months ago
7.31 =O I have never seen Brady before... just love these videos!
wacko031290 1 year ago
When I was 20 I knew intuitively that time is not part of space. It took me 32 years to understand rationally that according to mathematical formalism X4 = ict time is numerical order of photon motion in 4D space.
TimeEinstein 1 year ago
An interesting biological sidelight: our eyes see in three colors: magenta, green and green-yellow - that is all. The colors below yellow-green are determined by a calculation done by the brain based on the magnitude of the eye-yellow-green and the difference between that and the eye-green. Blue is eye-magenta without any eye-green, magenta is eye-magenta with some eye-green in it.. The brain is indeed, a weird and wonderful instrument.
puncheex 1 year ago
... The traditional colors of red, green and blue aren't basic; they're derived by complex calculations the brain does over it's entire multi-megapixel "screen" at rates too high to detect, probably (I'd guess) by massive parallelization of the computations done in analog (of course).
puncheex 1 year ago
so THATS what Brady looks like @7:32
me835 1 year ago
Wow! photons can move a space ship with a giant sale? How can they do that if they don't any have any mass? Excellent video as usual! please keep posting them!
cristianfcao 1 year ago
@cristianfcao: They have no rest mass (that is, mass of their own, that can be measured at rest). But when they are moving at the SoL (which they always are) they have energy, and according to E = mc^2, they also have a relativistic mass. With mass and velocity, they have momentum, and that momentum is to some extent transferred when the photon is reflected or absorbed.
puncheex 1 year ago
@puncheex Nice! I didn't know about that! Thanks a lot for your answer!
cristianfcao 1 year ago
Dearly To those idiots who dare to dislike this video,
"AVADA KEDAVRA!"
Sinceirly, SixtySymbols.
aashish7kumar5 1 year ago
So does that mean that there is less atmosphere in certain parts of the world wince the sky is different colours at the same time of day, for example the grey skies in England and the blue skies in Australia, or is that due to man-made output?
VeryOxygen 1 year ago
@VeryOxygen: Yes. The skies over Vail, Colorado are famous for their deep blue color caused by the elevation of the town at 11,500' (that's 3500 meters for those unaccustomed to the queen's system). Photographers flock there to take pictures of the Maroon Bells against that sky.
The gray skies anywhere are due to poor weather. Perhaps you noticed.
puncheex 1 year ago
@puncheex ahh I see. Thanks man!
VeryOxygen 1 year ago
Taking pity, I direct those who cannot see the blue from their vantage point to here: shutterstockDOTcom/pic-8332879/stock-photo-the-maroon-bells-in-the-white-river-national-forest-of-colorado.html
puncheex 1 year ago
Why is it that we still see blue or any other color on the earth that had been scattered by the atmosphere? Is it that only a portion of those photons with those wavelengths are scattered by hitting atoms and everything else is making it successfully without being disturbed?
xeroaxlvx 1 year ago
@xeroaxlvx: Let's say that the shorter wavelength part of the visible spectrum is preferentially scattered. At noon, the sunlight is white (all colors); it still has a large proportion of the blue light that it started with, and yet, not all of it; looking at the sky off to the side, some blue light is careening off an oxygen molecule and smacking your eye. As the atmospheric path lengthens (as near sundown), more blue is scattered, leaving the redder components to blaze in the sunset.
puncheex 1 year ago
Did anyone else get sucked into the cricket and stop listening to the commentary?
cuntylishus 1 year ago
Enlightening =]
orgminyak 1 year ago
So if the atmosphere was thicker at noon the sky would be yellow? and if it was even thicker at noon the sky would be red?
pauldve 1 year ago
@pauldve Yes.
Juxtaroberto 1 year ago
@pauldve: No - the sun would be yellower; the sky would be paler blue, due to more of the green (and maybe even some red) being scattered by the thicker atmosphere. Eventually you would get a uniform gray, where all light is being reflected, likely many times.
puncheex 1 year ago
I didn't know that crickets had balls.
BuickDoc 1 year ago
What is cricket?
BuickDoc 1 year ago
I didn't realize that chick wasn't british until that dude told her about torches.
Kowzorz 1 year ago
NOOO! This was the last video in my list. *Disappointed*
Zeldakitteh 1 year ago
I don't understand, Photons have no mass nor are they real particles.. how could we hypothetically make a solar sail or compare photons to a cricket ball without mass?
Moviemann345 1 year ago
@Moviemann345 its a pretty bad analogy..
jaggedrocksk8 1 year ago
@Moviemann345 That's got me stumped as well.
I thought photons did have mass.
Vennificus 1 year ago
@Moviemann345 From what i can conclude, they can capture the momentum, i.e the energy of the photon.
92blink182 1 year ago
@Moviemann345 Photons ARE real particles, although there are such things as virtual photons. The reason we can compare the photon to the cricket ball is that it isn't the mass which move stuff in a collision, it's the transfer of energy.
Juxtaroberto 1 year ago
@Juxtaroberto: Well, technically, transfer of momentum. Photons are created running at the SoL and have energy. According Einstein they therefore have a "relativistic" mass, and where there is velocity and mass there is momentum. With momentum they can push.
puncheex 1 year ago
when u sit in an airplane, and it makes a turn, just look into the sky, looks a little bit creepy, like ur close to space, very dark...such impressive
Serpico261 2 years ago
what about dawn? the light has to go through a layer of atmosphere just as thick as during dusk... but it doesnt look redish; it looks rather light blue.
Why? does it have anything to do with doppler effect?
donguateque 2 years ago
Sunrise and sunset look the same - red. The only thing I can think of is maybe the direction you see sunrise from has high objects in it, blocking the full view.
chrisofnottingham 2 years ago
@donguateque: No; the sun looks reddish (if there is high humidity, dust or smoke) or yellow if there is clear air; it's the sky that is blue. There is essentially zero velocity difference between earth and the sun along their common axis, so no doppler (OK, there is a little from the Earth's spin, but it's minor; a mere 1300 km/hr or so, max).
puncheex 1 year ago
thanks, its great to see educational videos on youtube :)
james0music 2 years ago
I think it would be very nice to see a video on wave particle duality.
Its an interesting concept and has been mentioned in this video, and is linked to other videos like wave function.
mrrig91 2 years ago
So, blue gets scattered and all other colors go through and as a result we see blue skies. But during sunset only red and orange go through the rest get scattered and we see red and orange??
sounds like contradiction to me!!
ttsodd 2 years ago
At sunset, light has to travel through a thicker atmosphere than at noon. So by the time the light hits our eyes, almost all of the blue light has been absorbed and scattered out.
CathySander 2 years ago
@ttsodd: Look, pure sunlight before it enters the atmosphere is white (with a very slight emphasis on the yellow). Things in the atmosphere, gas molecules, dust, smoke and humidity) all preferentially scatter blue and let the red and yellow through. As the smoke, etc get thicker, the effect reaches from the blue into the green, maybe even into the yellow, scattering them all and leaving the orange and red to shine through. Look at the sun through a forest fire's smoke, and you'll get blood red.
puncheex 1 year ago
... When you look directly into the sun (protection for your eyes, please) you get what passes through unscattered. When you look at the sky, you get the scattered colors.
puncheex 1 year ago
Very cool
Grey80002 2 years ago
the chik is hawd ! :D
Pakuna 2 years ago
@Pakuna: She has a great smile and a delightful personality.
puncheex 1 year ago
3 50 MUSE BUTTERFLIES AND HURRINCANEs piano solo. yessss
ciucinciu 2 years ago
Comment removed
nige503 2 years ago
wow that incredible, i never knew a torch and water would do that
simba00784 2 years ago 2
Will you be doing another gamma video on the Lorentz factor? I've been looking into special relativity quite a bit lately and it would be cool to see a video on all of the weird and wonderful things that happen to things that move quickly, like Lorentz contraction and time dilation, etc.
DancingRoboClown 2 years ago
Isn't momentum calculated by mass x velocity? Photons don't have mass, so shouldn't 0 x V = 0?
How can photons have momentum?
Kev888 2 years ago 2
Good question. First I imagined that Photons had very little mass, but after a quick googling I found wikipedia's article on Invariant Mass. I'm not a physicist, so I would appreciate an explanation for the layman.
edcrypt 2 years ago
photons have relativistic momentum.
using einstein's famous energy equation and adding the relativistic momentum term (giving the general energy expression):
E^2 = (m^2) x (c^4) + (p^2) x (c^2)
E is energy, m is rest mass, p is momentum, c is speed of light. photons have zero mass so E = pc. the E of photons exist in distinct packets that only depend on the frequency, f (or wavelength) (the photoelectric effect)... E=hv, h is plancks constant.
so E = pc = hf and finally, p = hf / c
astropixie101 2 years ago 15
@astropixie101 as I have absolutely no idea what you are talking about, I will take your word for it that you know your stuff
MasterOfSuprise 10 months ago
This has been flagged as spam show
oops... i said E=hv and meant E=hf
astropixie101 2 years ago 2
@Kev888It's a rule in relativistic physics that any particle with no rest mass can only exist moving at the speed of light. Thus the photon, and (some physicists think) the neutrino. OTOH, any particle with rest mass can only approach the speed of light.
puncheex 1 year ago
@puncheex Of course photons travel faster than the speed of light, from their point of view. As, at the speed of light, time doesn't pass for them, they move instantly, across the universe.
gamesbok 1 year ago
@gamesbok: What do you care what a photon thinks? :)
puncheex 1 year ago
@puncheex One of those little bastards stole my Rolex.
gamesbok 1 year ago
@gamesbok: Well I hope he uses it to good effect. We could use some good pix of the other side of the universe. Assuming you ever get it back.
puncheex 1 year ago
this English speaker calls it a flashlight!
Xraller 2 years ago 3
wouldn't a Torch imply Fire?? It should be a Flashlight... there i settled it . LOL :o
archaedemos 2 years ago 3
great
windowlicker1 2 years ago
great channel on YouTube, very informative. Cant stop digging through the symbols.
menges70 2 years ago 22
Noooo! Science has destroyed the romance of sunsets!
Just kidding.
leporidus 2 years ago 2
I have always wanted to know why the sky is blue. Before I saw this I thought it was because of the presence of minute traces of cobalt. Now I know...
Hewpie 2 years ago 3
Why are the ads for this channel always "Christian Rock Music" or "Jesus loves you"?
Jiraya12345 2 years ago
I usually get "Play crappy RPGs with scantily-clad women!"
Envergure 2 years ago 2
it depends on your country.. i never get any of the ones you said
ricardjorg 2 years ago
Most of the photon-related stuff you guys talk about have good classical (wave-like) or semiclassical (sort of wave-like) explanations. For instance, why the sky is blue.
You should've talked to a quantum optician! For instance, observing double slit interference one photon at a time is a remarkable demonstration of truly quantum mechanical photonic behaviour!
starkshift 2 years ago 11
stay tuned.... we've filmed some of that and it is coming soon!
sixtysymbols 2 years ago 8
Can't wait!
HLSDK 2 years ago
Awesome, can't wait! :)
starkshift 2 years ago
totally agree : although this was as good vid:: Check my photon splitting Vid out: (:
Anyone can reproduce it!!!
archaedemos 2 years ago
Yeah! PHOTONS! WOO!
You guy's should have gone a bit deeper on this one :/
NAMLegolas 2 years ago
How about a totally transparent space ship. Lets not get too bogged down on how we make a space ship transparent alright?
Then, using... Buttons, we make certain parts opaque.
If we wanna travel forward, make the back opaque.
Etc etc.
harryh111111 2 years ago
No what we should do is make it black. Make the lights black, the buttons black, the walls black, the carpets black, even the padding under the carpet should be black :) And I'm sure somebody will read this and excitedly type away at what the reference is. And to those people I have this to say "You big nerds" :)
Woad25 2 years ago 2
Restaurant at the End of the Universe??
qqwwwwwwww 2 years ago
Oh, you joker you.
harryh111111 2 years ago
Very fitting reference. A great mind from England, on a video from a university from the UK, and it's a bit more fitting as I just watched the movie last night after reading the book two semesters ago. I pride myself on being a "big nerd". I hope I actually got the reference...
Cyrathil 2 years ago
@harryh111111: You seek a General Products #4 hull. Completely indestructible, transparent to all energy below UV, one single piece sphere 1000' in diameter. See wordiqDOTcom/definition/General_Products_%28Larry_Niven%29
puncheex 1 year ago
PHOTONS ARE FUN!
harryh111111 2 years ago
Now thats a British analogy
drumbum99 2 years ago
hahahaha "flashlight's a torch"
yared94 2 years ago