You’re cherry-picking individual sentences out of what I quoted and ignoring the context, despite that context being right there in my comment. Please don’t do that.
Hm. Not sure you want to pick this reporter as your example of philosophical sophistication. Next.
What does philosophical sophistication matter? Are the quoted facts false? Is “A blue-violet laser blasts the atom, which then absorbs and re-emits enough light particles to be photographed with conventional equipment” a lie?
… a long exposure (on the order of 10 seconds) was used to capture the atom, and then a flash was used to illuminate the surroundings. Without this technique, the atom would not be visible in an image that also included the surroundings. What it is not, however, is a pronouncement on the inherent invisibility of atoms.
Why does it need to be such a pronouncement? You linked the strontium atom photograph as evidence for your claim that I could look at an atom and see what color it is. But said photograph is not, in fact, evidence for that claim, as my links and quotes explain.
Your one piece of provided evidence being disqualified, do you have any other evidence for your claim? If not, then we’re back to my answer: no, I cannot look at an atom someone hands me and see what color it is. (And while we’re at it, how exactly do you propose that someone “hand me an atom”, anyhow? I let this part slide before, but since we’re nitpicking…)
Congrats, you found a reporter saying the thing. However, this random reporter’s opinion isn’t necessarily true.
What about the facts that reporter reports? Are they true? Or do you claim that reporter was lying about some or all of the following:
the purple speck at the center of this photo is not the true size of the strontium atom itself
When bathed in a specific wavelength of blue light, strontium creates a glow hundreds of times wider than the radius of the atom itself (which is about a quarter of a nanometer, or 2.5x10 to the −7 meters, Nadlinger said).
This glow would be barely perceptible with the naked eye but becomes apparent with a little camera manipulation.
“The apparent size you see in the picture is what we’d call optical aberration,” Nadlinger said.
Which of these are false?
To be honest, I’m not really sure if an atom really is visible to the naked eye … Let’s do some math. … [math snipped] … So if you were to put your eye 12 cm away from the atom, it would be as bright as the faintest stars humans can see in the sky. Farther than that and I’m happy to agree you couldn’t see it with your naked eye.
I am not a physicist and cannot evaluate your math or your claims. Do you have some citation, to some reliable source (or preferably multiple such, but one will do for now) confirming that atoms are visible with the unaided naked eye? And, do you have any examples you can cite of humans seeing individual atoms with their unaided vision?
(It would also help somewhat if other physics-knowledgeable Less-Wrongers would comment on whether this math makes sense—and why, if it does make sense, it seems to contradict the reporting of the facts surrounding the strontium atom demonstration.)
What does philosophical sophistication matter? Are the quoted facts false? Is “A blue-violet laser blasts the atom, which then absorbs and re-emits enough light particles to be photographed with conventional equipment” a lie?
The sentence you quote is true. And “The sun blasts the cover of the book, which then absorbs and re-emits photons to be photographed with conventional equipment” is an equally valid description of taking a picture of a book. I’m honestly confused as to what you’re expecting me to find inconsistent here. Are you implying that since you can describe scattering of light using scientific talk like “photons” and “re-emission,” you can’t describe it using unscientific talk like “the atom was purple?”
Ah, or maybe you’re expecting me to know that you mean something like “What if the atom is only purple because it’s being ‘blasted’ with purple photons, making this photo useless in terms of understanding its color?” That’s a reasonable thing to think if you’ve never had reason to study atomic spectra, but it turns out the direction of causation is just the opposite—scientists chose a purple laser because that’s one of the few colors the atom would absorb and re-emit.
I think what this shows is that my perception of what’s “everyday” has definitely been skewed by a physics degree, and things that just seem like the way everything works to me might seem like unusual and rare sciencey phenomena to everyone else.
Like, you ask me to refute this fact or that fact, but I already quoted precisely the statements I thought deserved highlighting from the articles, and none of them were facts about how light or atoms work. That should tell you that I have zero intention of overthrowing our basic understanding of optics. But since we might have different understandings of the same sentences, I will go through the specific ones you highlight and try to read your mind.
the purple speck at the center of this photo is not the true size of the strontium atom itself
This is due to the limitations of the camera—even if the light came from a single point, the camera wouldn’t be able to focus it back down to a single pixel on the detector. This is due to a combination of imperfections in the lenses plus physics reasons that make all pictures a little blurry. The same thing happens in the human eye—even if we were looking at a point source of purple light, it would look to our eye like a little round dot of purple light.
Mind reading: Maybe you are implying that if the camera can’t resolve the true size of the atom, it’s not “really” a picture of the atom. This is sort of true—if the atom was blue on the left and red on the right (let’s ignore for a moment the physical impossibility), it would still look purple in this photo despite never emitting purple photons. Of course, we do know that it emits purple photons. But I think the thing that is actually mistaken about worrying about whether this is “really” the atom is that it’s forgetting the simplicity of just looking at things to tell what color they are.
Even when I argue that things invisible to the planet eye, like the planet Neptune, can have color, it’s not necessarily because of complicated sciencey reasoning, but more some heuristic arguments about process that preserve color. You can look at Neptune through a telescope and it has color then—so since telescopes preserve color, Neptune is blue. Or if I took a red teapot and shot it into space somewhere between the orbit of Mars and Jupiter and we never saw it again, it would still be red, because in color-logic, moving something somewhere else is a process that preserves color.
In short, I didn’t bother to actually do the math on whether you could see an atom with the naked eye until today because I think of time lapse photography or using lenses to look at something as process that preserve “intuitive color.”
When bathed in a specific wavelength of blue light, strontium creates a glow hundreds of times wider than the radius of the atom itself (which is about a quarter of a nanometer, or 2.5x10 to the −7 meters, Nadlinger said).
I’m not sure what the reporter is getting at here. I think they are comparing the wavelength of the light to the electron radius of the atom, and the wavelength of the light is what they mean by “creates a glow.” It’s definitely inaccurate. But I’m not sure I could do better to explain what’s going on to an audience that doesn’t know quantum mechanics. Maybe a water analogy? The atom emitting a photon is like a tiny stone tossed into a pond. The size of the ripples emitted by the tiny stone is a lot bigger than the size of the stone itself.
Mind reading: Maybe you read this as something like “We’re not actually seeing the atom, we’re just seeing ‘a glow created by the atom’ that’s a lot bigger than the atom, therefore this isn’t a picture of the atom.” That’s false. This goes back to why I was making fun of the reporter who said “We’re not seeing the atom, we’re just seeing the light emitted by the atom.” Seeing the light emitted by something is what seeing is. You could just as well say “I’m not actually seeing my hand, I’m just seeing the light emitted by my hand,” and you’d be just as wrong. Learning about photons should not destroy your ability to see things, and if it does you’re doing philosophy very wrong.
This glow would be barely perceptible with the naked eye but becomes apparent with a little camera manipulation.
Yup, this is that “long exposure to the atom + short flash of the surroundings” technique I talked about in the previous comment. Maybe you see the word “manipulation” and assume that everything is meaningless and this “doesn’t count”? I think this question stops being useful when you understand what was actually done to get the photo.
“The apparent size you see in the picture is what we’d call optical aberration,” Nadlinger said.
I am familiar with the physical facts you’ve described in this comment. But, what seems to be the case is that you are confused about what color is.
For example:
Of course, we do know that it emits purple photons.
There is no such thing as “purple photons”. (If you doubt this, consider whether there’s such a thing as “magenta photons”—and if not, why not, if there can be “purple photons”—and also whether, when you look at a picture of an orange on your computer, the computer’s screen is emitting “orange photons”.)
Ah, or maybe you’re expecting me to know that you mean something like “What if the atom is only purple because it’s being ‘blasted’ with purple photons, making this photo useless in terms of understanding its color?” That’s a reasonable thing to think if you’ve never had reason to study atomic spectra, but it turns out the direction of causation is just the opposite—scientists chose a purple laser because that’s one of the few colors the atom would absorb and re-emit.
What would the atom look like in ordinary illumination (say, sunlight at noon, or a flourescent light, or any other common lighting conditions)? Would it also look purple?
Even when I argue that things invisible to the planet eye, like the planet Neptune, can have color, it’s not necessarily because of complicated sciencey reasoning, but more some heuristic arguments about process that preserve color. You can look at Neptune through a telescope and it has color then—so since telescopes preserve color, Neptune is blue. Or if I took a red teapot and shot it into space somewhere between the orbit of Mars and Jupiter and we never saw it again, it would still be red, because in color-logic, moving something somewhere else is a process that preserves color.
In short, I didn’t bother to actually do the math on whether you could see an atom with the naked eye until today because I think of time lapse photography or using lenses to look at something as process that preserve “intuitive color.”
There is no fact of the matter about whether Neptune “is blue”. The physical facts which sentences like “a tomato is red” or “a banana is yellow” cash out into, are inapplicable to Neptune. We could say that Neptune “looks blue when viewed with the naked eye from Earth”—which would be false, because Neptune cannot be seen with the naked eye from Earth. We could also say that Neptune “looks blue when viewed through a telescope from Earth”—which would be true.
So, is a strontium atom purple? Well, let’s table that. Does a strontium atom look purple when viewed with the unaided naked eye in ordinary terrestrial lighting conditons? No; it cannot be seen with the unaided naked eye. (Right? Or do you say that it can?) Does a strontium atom look purple when subjected to laser light of a certain frequency, etc.? No; it still cannot be seen with the unaided naked eye, even then. Does a picture of a strontium atom which has been subjected to certain light etc., taken with a certain sort of long-exposure camera, etc., look purple? Clearly, yes.
Maybe you read this as something like “We’re not actually seeing the atom, we’re just seeing ‘a glow created by the atom’ that’s a lot bigger than the atom, therefore this isn’t a picture of the atom.” That’s false. This goes back to why I was making fun of the reporter who said “We’re not seeing the atom, we’re just seeing the light emitted by the atom.” Seeing the light emitted by something is what seeing is.
(This part is also confused, but I defer commenting on it, as I would like you to address the other things I’ve said in this comment and prefer to avoid distractions; I merely note it for the record.)
(I’m coming to this rather late, and will entirely understand if Said doesn’t want to resurrect an old discussion; if not, I hope no reader will take the lack of response to indicate that my points were just so compelling that Said had no answer to them.)
There is no such thing as “purple photons” [...]
I am unconvinced by your argument here (which may just indicate that I haven’t grasped what it is). The following position seems pretty reasonable to me: There are violet photons but not magenta photons. There are orange photons, but because of metamerism you can see something orange without any orange photons being involved. Violet photons are not violet in the same way as a piece of paper covered in violet dye is violet, but it’s reasonable to use the same word for both.
Would you care to make more explicit your reasons for saying that there is no such thing as a violet photon? (You actually said purple, as Charlie had done in the comment you were replying to, but I’m fairly sure your position is not “there are photons of some colours but not of others”. My apologies if I’ve misunderstood.)
What would the atom look like in ordinary illumination [...]
Like many things, it would look different in different conditions of illumination. Unlike most things we look at, its spectrum is composed of a few sharp peaks, so the relationship between its illumination and the colour we see (given sufficient “amplification” since of course a single atom can neither emit nor scatter very much light) is a bit unusual. (One can make macroscopic materials with similar properties and I don’t see any particular reason to deny that they have colour.)
There is no fact of the matter as to whether Neptune “is blue”. [...]
This seems like a matter of definitions, and I don’t like your definitions. Whatever difficulties there are about assigning a colour to Neptune are simple a consequence of the fact that it’s a long way away from us. (I think it’s clear that there’s a fact of the matter as to whether Mars is red: it is. If Neptune’s orbit were where Mars’s is, there’d be no difficulty saying that Neptune is blue.) Are you sure you want to say that whether a thing has a definite colour can change merely on account of the distance between it and us? If we sent astronauts to Neptune instead of just probes, would there then be a fact of the matter as to whether Neptune has a colour? If there were an accident and the astronauts died, would Neptune’s colour-having-ness change? If I take an orange, lock it in a vault (illuminated, let’s say, by an incandescent bulb in the vault), and throw away the key, does there stop being a fact of the matter as to whether the orange is orange?
Incidentally: yes, the reporter is wrong about something. A quarter of a nanometre is not 2.5 x 10^-7 metres.
Well, you are free to use the word “color” in such a way that there is no fact of the matter about whether Neptune has a color if you wish. But I think that this directs us into a definitional argument that I don’t feel like having—in fact, almost a perfect analogy to “If a tree falls in a forest and there’s no one to hear it, does it make a sound?”
No, this isn’t a definitional argument. Insofar as your view leads you to misunderstand very real facts about human color perception, it is mistaken. Again, consider the questions I asked about “photon color” at the start of the grandparent comment.
This sort of misconception is quite common, especially among mathematically or physically inclined folks who have not studied color theory and the psychophysics of color. It leads, unfortunately, to mistakes in the design and implementation of various systems that have to use or manipulate color in one way or another.
It’s certainly your right to tap out of the conversation. But I hope that you’ll consider what I’ve said (and the same goes for anyone else reading this exchange who feels that Charlie Steiner’s perspective makes sense).
You’re cherry-picking individual sentences out of what I quoted and ignoring the context, despite that context being right there in my comment. Please don’t do that.
What does philosophical sophistication matter? Are the quoted facts false? Is “A blue-violet laser blasts the atom, which then absorbs and re-emits enough light particles to be photographed with conventional equipment” a lie?
Why does it need to be such a pronouncement? You linked the strontium atom photograph as evidence for your claim that I could look at an atom and see what color it is. But said photograph is not, in fact, evidence for that claim, as my links and quotes explain.
Your one piece of provided evidence being disqualified, do you have any other evidence for your claim? If not, then we’re back to my answer: no, I cannot look at an atom someone hands me and see what color it is. (And while we’re at it, how exactly do you propose that someone “hand me an atom”, anyhow? I let this part slide before, but since we’re nitpicking…)
What about the facts that reporter reports? Are they true? Or do you claim that reporter was lying about some or all of the following:
Which of these are false?
I am not a physicist and cannot evaluate your math or your claims. Do you have some citation, to some reliable source (or preferably multiple such, but one will do for now) confirming that atoms are visible with the unaided naked eye? And, do you have any examples you can cite of humans seeing individual atoms with their unaided vision?
(It would also help somewhat if other physics-knowledgeable Less-Wrongers would comment on whether this math makes sense—and why, if it does make sense, it seems to contradict the reporting of the facts surrounding the strontium atom demonstration.)
The sentence you quote is true. And “The sun blasts the cover of the book, which then absorbs and re-emits photons to be photographed with conventional equipment” is an equally valid description of taking a picture of a book. I’m honestly confused as to what you’re expecting me to find inconsistent here. Are you implying that since you can describe scattering of light using scientific talk like “photons” and “re-emission,” you can’t describe it using unscientific talk like “the atom was purple?”
Ah, or maybe you’re expecting me to know that you mean something like “What if the atom is only purple because it’s being ‘blasted’ with purple photons, making this photo useless in terms of understanding its color?” That’s a reasonable thing to think if you’ve never had reason to study atomic spectra, but it turns out the direction of causation is just the opposite—scientists chose a purple laser because that’s one of the few colors the atom would absorb and re-emit.
I think what this shows is that my perception of what’s “everyday” has definitely been skewed by a physics degree, and things that just seem like the way everything works to me might seem like unusual and rare sciencey phenomena to everyone else.
Like, you ask me to refute this fact or that fact, but I already quoted precisely the statements I thought deserved highlighting from the articles, and none of them were facts about how light or atoms work. That should tell you that I have zero intention of overthrowing our basic understanding of optics. But since we might have different understandings of the same sentences, I will go through the specific ones you highlight and try to read your mind.
This is due to the limitations of the camera—even if the light came from a single point, the camera wouldn’t be able to focus it back down to a single pixel on the detector. This is due to a combination of imperfections in the lenses plus physics reasons that make all pictures a little blurry. The same thing happens in the human eye—even if we were looking at a point source of purple light, it would look to our eye like a little round dot of purple light.
Mind reading: Maybe you are implying that if the camera can’t resolve the true size of the atom, it’s not “really” a picture of the atom. This is sort of true—if the atom was blue on the left and red on the right (let’s ignore for a moment the physical impossibility), it would still look purple in this photo despite never emitting purple photons. Of course, we do know that it emits purple photons. But I think the thing that is actually mistaken about worrying about whether this is “really” the atom is that it’s forgetting the simplicity of just looking at things to tell what color they are.
Even when I argue that things invisible to the planet eye, like the planet Neptune, can have color, it’s not necessarily because of complicated sciencey reasoning, but more some heuristic arguments about process that preserve color. You can look at Neptune through a telescope and it has color then—so since telescopes preserve color, Neptune is blue. Or if I took a red teapot and shot it into space somewhere between the orbit of Mars and Jupiter and we never saw it again, it would still be red, because in color-logic, moving something somewhere else is a process that preserves color.
In short, I didn’t bother to actually do the math on whether you could see an atom with the naked eye until today because I think of time lapse photography or using lenses to look at something as process that preserve “intuitive color.”
I’m not sure what the reporter is getting at here. I think they are comparing the wavelength of the light to the electron radius of the atom, and the wavelength of the light is what they mean by “creates a glow.” It’s definitely inaccurate. But I’m not sure I could do better to explain what’s going on to an audience that doesn’t know quantum mechanics. Maybe a water analogy? The atom emitting a photon is like a tiny stone tossed into a pond. The size of the ripples emitted by the tiny stone is a lot bigger than the size of the stone itself.
Mind reading: Maybe you read this as something like “We’re not actually seeing the atom, we’re just seeing ‘a glow created by the atom’ that’s a lot bigger than the atom, therefore this isn’t a picture of the atom.” That’s false. This goes back to why I was making fun of the reporter who said “We’re not seeing the atom, we’re just seeing the light emitted by the atom.” Seeing the light emitted by something is what seeing is. You could just as well say “I’m not actually seeing my hand, I’m just seeing the light emitted by my hand,” and you’d be just as wrong. Learning about photons should not destroy your ability to see things, and if it does you’re doing philosophy very wrong.
Yup, this is that “long exposure to the atom + short flash of the surroundings” technique I talked about in the previous comment. Maybe you see the word “manipulation” and assume that everything is meaningless and this “doesn’t count”? I think this question stops being useful when you understand what was actually done to get the photo.
See above about the limitations of cameras.
I am familiar with the physical facts you’ve described in this comment. But, what seems to be the case is that you are confused about what color is.
For example:
There is no such thing as “purple photons”. (If you doubt this, consider whether there’s such a thing as “magenta photons”—and if not, why not, if there can be “purple photons”—and also whether, when you look at a picture of an orange on your computer, the computer’s screen is emitting “orange photons”.)
What would the atom look like in ordinary illumination (say, sunlight at noon, or a flourescent light, or any other common lighting conditions)? Would it also look purple?
There is no fact of the matter about whether Neptune “is blue”. The physical facts which sentences like “a tomato is red” or “a banana is yellow” cash out into, are inapplicable to Neptune. We could say that Neptune “looks blue when viewed with the naked eye from Earth”—which would be false, because Neptune cannot be seen with the naked eye from Earth. We could also say that Neptune “looks blue when viewed through a telescope from Earth”—which would be true.
So, is a strontium atom purple? Well, let’s table that. Does a strontium atom look purple when viewed with the unaided naked eye in ordinary terrestrial lighting conditons? No; it cannot be seen with the unaided naked eye. (Right? Or do you say that it can?) Does a strontium atom look purple when subjected to laser light of a certain frequency, etc.? No; it still cannot be seen with the unaided naked eye, even then. Does a picture of a strontium atom which has been subjected to certain light etc., taken with a certain sort of long-exposure camera, etc., look purple? Clearly, yes.
(This part is also confused, but I defer commenting on it, as I would like you to address the other things I’ve said in this comment and prefer to avoid distractions; I merely note it for the record.)
(I’m coming to this rather late, and will entirely understand if Said doesn’t want to resurrect an old discussion; if not, I hope no reader will take the lack of response to indicate that my points were just so compelling that Said had no answer to them.)
I am unconvinced by your argument here (which may just indicate that I haven’t grasped what it is). The following position seems pretty reasonable to me: There are violet photons but not magenta photons. There are orange photons, but because of metamerism you can see something orange without any orange photons being involved. Violet photons are not violet in the same way as a piece of paper covered in violet dye is violet, but it’s reasonable to use the same word for both.
Would you care to make more explicit your reasons for saying that there is no such thing as a violet photon? (You actually said purple, as Charlie had done in the comment you were replying to, but I’m fairly sure your position is not “there are photons of some colours but not of others”. My apologies if I’ve misunderstood.)
Like many things, it would look different in different conditions of illumination. Unlike most things we look at, its spectrum is composed of a few sharp peaks, so the relationship between its illumination and the colour we see (given sufficient “amplification” since of course a single atom can neither emit nor scatter very much light) is a bit unusual. (One can make macroscopic materials with similar properties and I don’t see any particular reason to deny that they have colour.)
This seems like a matter of definitions, and I don’t like your definitions. Whatever difficulties there are about assigning a colour to Neptune are simple a consequence of the fact that it’s a long way away from us. (I think it’s clear that there’s a fact of the matter as to whether Mars is red: it is. If Neptune’s orbit were where Mars’s is, there’d be no difficulty saying that Neptune is blue.) Are you sure you want to say that whether a thing has a definite colour can change merely on account of the distance between it and us? If we sent astronauts to Neptune instead of just probes, would there then be a fact of the matter as to whether Neptune has a colour? If there were an accident and the astronauts died, would Neptune’s colour-having-ness change? If I take an orange, lock it in a vault (illuminated, let’s say, by an incandescent bulb in the vault), and throw away the key, does there stop being a fact of the matter as to whether the orange is orange?
Incidentally: yes, the reporter is wrong about something. A quarter of a nanometre is not 2.5 x 10^-7 metres.
Well, you are free to use the word “color” in such a way that there is no fact of the matter about whether Neptune has a color if you wish. But I think that this directs us into a definitional argument that I don’t feel like having—in fact, almost a perfect analogy to “If a tree falls in a forest and there’s no one to hear it, does it make a sound?”
So yeah, it’s been fun :)
No, this isn’t a definitional argument. Insofar as your view leads you to misunderstand very real facts about human color perception, it is mistaken. Again, consider the questions I asked about “photon color” at the start of the grandparent comment.
This sort of misconception is quite common, especially among mathematically or physically inclined folks who have not studied color theory and the psychophysics of color. It leads, unfortunately, to mistakes in the design and implementation of various systems that have to use or manipulate color in one way or another.
It’s certainly your right to tap out of the conversation. But I hope that you’ll consider what I’ve said (and the same goes for anyone else reading this exchange who feels that Charlie Steiner’s perspective makes sense).