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Let me up the ante, not only can we detect single photons. A pioneering study at the interface of biology and physics found, that isolated rod photoreceptors o

Let me up the ante, not only can we detect single photons. A pioneering study at the interface of biology and physics found, that isolated rod photoreceptors of frogs are sensitive to differences in the light sources statistical properties, e.g coherent (laser) vs thermal (sun, light-bulb) vs sub-poissonian (resonance fluorescence of quantum dots) light statistics: "Measurement of Photon Statistics with Live Photoreceptor Cells" (2012) [1] "The results indicate differences in average responses of rod cells to coherent and pseudothermal light of the same intensity and also differences in signal-to-noise ratios and second-order intensity correlation functions" It seems Lorentz hypothesis in 1911 was right, that the boundaries of our perception are set by basic laws of physics, and that we reach the limits of what is possible. === [1] [pdf] https://physics.aps.org/featured-article-pdf/10.1103/PhysRevLett.109.113601 https://physics.aps.org/featured-article-pdf/10.1103/PhysRev...

theoh 9y ago
I can't find what this Lorentz hypothesis of 1911 is, but surely you are claiming too much. Physical entities can detect X-rays, but humans haven't evolved that ability (except, recently, externally/collectively). The idea that our perceptual apparatus is optimal, rather than a contingent product of a particular evolutionary path, is easy to refute -- but maybe that isn't what you mean by "reach[ing] the limits of what is possible."
- mromanuk 9y ago
  We can reach maximum optimization of wathever physical property we use. For example our brain and it super efficiency vs a super computer.
  - bhaak 9y ago
    But humans had millions of years to evolve. The computer is only 70 years old. Give it 100 years and we will make it as efficient as a human brain, possibly even better. Evolution is a slow process. Non sentient trial and error. We beat that in time easily.
- splittingTimes 9y ago
  http://lmgtfy.com/?q=single-photon+sensitivity+in+human+vision+%22Lorentz%22+-quora http://lmgtfy.com/?q=single-photon+sensitivity+in+human+visi... "Hendrik Lorentz (of special relativity and Zeeman effect fame) is said to have calculated the number of photons in a flash of light that was considered at the time to be “just visible,” and found that the number was about 100 [2]. A significant fraction of photons was known to be lost in transmission through the eye, and the remaining photons would be spread over an area containing hundreds of rod cells, so it seemed likely that the individual rod cells were able to detect single photons. Perhaps the absorption of a single photon was even enough to cause the perception of light." [1] "Physiologists had already undertaken rough estimates of the faintest flash that could be reliably seen; Lorentz converted their units into energy per flash, then divided by Einstein’s result for the energy of one photon, and came up with the result that roughly 25-150 photons entering the human eye was enough to perceive a flash" [3] "[In a] landmark experiment by Hecht, Shlaer, and Pirenne (1942), which set out to determine the minimum number of photons (quanta) required for someone to perceive a flash of light. From their findings, Hecht et al. conclude that, under certain precise conditions, the average person only needs to detect around ten quanta for their visual system to detect the flash." [4] === [1] "TESTING THE LIMITS OF HUMAN VISION WITH QUANTUM STATES OF LIGHT" http://research.physics.illinois.edu/QI/Photonics/theses/holmes-thesis-e.pdf http://research.physics.illinois.edu/QI/Photonics/theses/hol... [2] M. A. Bouman, “History and Present Status of Quantum Theory in Vision,” in Sensory Communication, pp. 376–401, The MIT Press, sep 2012 [3] "Old and new results about single-photon sensitivity in human vision" http://repository.upenn.edu/cgi/viewcontent.cgi?article=1515&context=physics_papers http://repository.upenn.edu/cgi/viewcontent.cgi?article=1515... [4] "The Experiment Of Hecht Shlaer And Pirenne" https://www.ukessays.com/essays/psychology/the-experiment-of-hecht-shlaer-and-pirenne-psychology-essay.php https://www.ukessays.com/essays/psychology/the-experiment-of...
- theoh 9y ago
  OK, by way of acknowledgement of splittingTimes' downvoted clarification, it seems the phrase "the boundaries of our perception are set by basic laws of physics, and that we reach the limits of what is possible" comes verbatim from a text in which the context is clearly the detection of photons. So it wasn't intended to be a claim of optimality for the human perceptual apparatus in general.
Balgair 9y ago
The eyesight of mantis/pistol shrimp is similarly crazy in it's complexity and it's in an invertebrate. Evolution seems to pick out some crazy stuff when it comes to animals near the water-air interface. For instance, they are able to detect circularly-polarized light across multiple octaves of light with a single receptor, covering all the Stokes' vectors. I've done a fair bit of optics and I have NO idea how to begin constructing a quarter-wave plate that would cover multiple octaves. So crazy. https://en.wikipedia.org/wiki/Mantis_shrimp#Eyes https://en.wikipedia.org/wiki/Mantis_shrimp#Eyes
- djsumdog 9y ago
  I remember learning that from this video: https://www.youtube.com/watch?v=F5FEj9U-CJM https://www.youtube.com/watch?v=F5FEj9U-CJM

theoh 9y ago

I can't find what this Lorentz hypothesis of 1911 is, but surely you are claiming too much. Physical entities can detect X-rays, but humans haven't evolved that ability (except, recently, externally/collectively). The idea that our perceptual apparatus is optimal, rather than a contingent product of a particular evolutionary path, is easy to refute -- but maybe that isn't what you mean by "reach[ing] the limits of what is possible."

mromanuk 9y ago
We can reach maximum optimization of wathever physical property we use. For example our brain and it super efficiency vs a super computer.
- bhaak 9y ago
  But humans had millions of years to evolve. The computer is only 70 years old. Give it 100 years and we will make it as efficient as a human brain, possibly even better. Evolution is a slow process. Non sentient trial and error. We beat that in time easily.
splittingTimes 9y ago
http://lmgtfy.com/?q=single-photon+sensitivity+in+human+vision+%22Lorentz%22+-quora http://lmgtfy.com/?q=single-photon+sensitivity+in+human+visi... "Hendrik Lorentz (of special relativity and Zeeman effect fame) is said to have calculated the number of photons in a flash of light that was considered at the time to be “just visible,” and found that the number was about 100 [2]. A significant fraction of photons was known to be lost in transmission through the eye, and the remaining photons would be spread over an area containing hundreds of rod cells, so it seemed likely that the individual rod cells were able to detect single photons. Perhaps the absorption of a single photon was even enough to cause the perception of light." [1] "Physiologists had already undertaken rough estimates of the faintest flash that could be reliably seen; Lorentz converted their units into energy per flash, then divided by Einstein’s result for the energy of one photon, and came up with the result that roughly 25-150 photons entering the human eye was enough to perceive a flash" [3] "[In a] landmark experiment by Hecht, Shlaer, and Pirenne (1942), which set out to determine the minimum number of photons (quanta) required for someone to perceive a flash of light. From their findings, Hecht et al. conclude that, under certain precise conditions, the average person only needs to detect around ten quanta for their visual system to detect the flash." [4] === [1] "TESTING THE LIMITS OF HUMAN VISION WITH QUANTUM STATES OF LIGHT" http://research.physics.illinois.edu/QI/Photonics/theses/holmes-thesis-e.pdf http://research.physics.illinois.edu/QI/Photonics/theses/hol... [2] M. A. Bouman, “History and Present Status of Quantum Theory in Vision,” in Sensory Communication, pp. 376–401, The MIT Press, sep 2012 [3] "Old and new results about single-photon sensitivity in human vision" http://repository.upenn.edu/cgi/viewcontent.cgi?article=1515&context=physics_papers http://repository.upenn.edu/cgi/viewcontent.cgi?article=1515... [4] "The Experiment Of Hecht Shlaer And Pirenne" https://www.ukessays.com/essays/psychology/the-experiment-of-hecht-shlaer-and-pirenne-psychology-essay.php https://www.ukessays.com/essays/psychology/the-experiment-of...
theoh 9y ago
OK, by way of acknowledgement of splittingTimes' downvoted clarification, it seems the phrase "the boundaries of our perception are set by basic laws of physics, and that we reach the limits of what is possible" comes verbatim from a text in which the context is clearly the detection of photons. So it wasn't intended to be a claim of optimality for the human perceptual apparatus in general.

Balgair 9y ago

The eyesight of mantis/pistol shrimp is similarly crazy in it's complexity and it's in an invertebrate. Evolution seems to pick out some crazy stuff when it comes to animals near the water-air interface. For instance, they are able to detect circularly-polarized light across multiple octaves of light with a single receptor, covering all the Stokes' vectors. I've done a fair bit of optics and I have NO idea how to begin constructing a quarter-wave plate that would cover multiple octaves. So crazy. https://en.wikipedia.org/wiki/Mantis_shrimp#Eyes https://en.wikipedia.org/wiki/Mantis_shrimp#Eyes

djsumdog 9y ago
I remember learning that from this video: https://www.youtube.com/watch?v=F5FEj9U-CJM https://www.youtube.com/watch?v=F5FEj9U-CJM