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10 days agoYour first sentence is a rule 1 violation (“be respectful and inclusive”), could you amend or remove it? Criticize the ideas (preferably with sources) but not the person. Thanks!
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Cake day: June 19th, 2023
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Per rule 9, could you provide a source for your interpretation of the double slit experiment, specifically that “there is no sort of wave collapse” and “the photons absorbed by film or eyes were just not impacting the surface because they were absorbed elsewhere, causing less friction between the photons and changing the patterns on the surface.”?
This appears contradictory to the standard quantum mechanical explanation for the interference pattern, which is that the wavefunction of the photons passes through both slits, interfering with itself and changing the probability of detection or interaction at specific points along the film/sensor.
The effect isn’t unique to photons and has been observed with electrons, atoms, and even large molecules. As long as the slit size and spacing are comparable to the wavelength of the particle wavefunction it’ll work.
The photon wavefunction being a superposition of position states that self-interact, and then collapse into a single state/location when interacting with a non-quantum object are fundamental to quantum mechanics, and are part of the reason this experiment is such a great introduction to QM. The many worlds interpretation of wavefunction collapse is not fundamental- it’s one of many interpretations for what the math of QM means and not even the most popular amongst theorists (that’d be the Copenhagen Interpretation).
I’m deleting this post because the proposed experiment appears to be endorsing suicide. I’d encourage you to please resubmit a version of your question that doesn’t involve self harm.
The x-axis range spans the same region of “photon energy” space in both plots. The data starts at about 280 nm in the first plot, which is 1000 THz (the maximum value in the second plot).
The stretching effect caused by working in different x-axis units is because the units don’t map linearly, but are inversely proportional. A 1 nm wide histogram bin at 1000 nm will contain the histogram counts corresponding to a 0.3 THz wide region at 300 THz in the frequency plot. Another 1 nm wide bin at 200 nm will correspond to a 7.5 THz wide region located at 1500 THz in the frequency plot.
You can get a sense of how this works just by looking at how much space the colorful visible light portion of the spectrum takes up on each plot. In the wavelength plot, by eye I’d say visible light corresponds to about 1/6 the horizontal axis scale. In the frequency plot, it’s more like 1/4.
That normalization is necessary because otherwise exactly how you bin the data would change the vertical scale, even if you used the same units. For example, consider the first plot. Let’s assume the histogram bins are uniformly 1 nm wide. Now imaging rebinning the data into 2 nm wide bins. You would effectively take the contents of 2 bins and combine them into one, so the vertical scale would roughly double. 2 plots would contain the same data but look vastly different in magnitude. But if in both cases you divide by bin width (1 nm or 2 nm, depending) the histogram magnitudes would be equal again. So that’s why the units have to be given in “per nm” or “per THz).
I believe the idea is that a single bright star in the frame (the guide star) is used for selecting the frames. The point spread function (PSF) is just going to be some function that describes the blurred shape you would observe with the detector for an input point source. You then select frames in which the guide star is well centered, compared to its overall distribution.
I think your guess on “sync-resampled” is correct. They increased the “resolution” by a factor of 4, so that when they realign the chosen frames to center the guide star, they can do so at a sub-pixel precision.
You may want to check out chapter 3 in the thesis, particularly section 3.5.3. The give a lot more detail on the process than you’ll be able to find in the paper. A well-written PhD thesis can be 1000x more valuable than the journal article it ultimately produces, because it contains all the specific details that can be glossed over in the final paper.
This isn’t exactly my area of expertise, but I have some information that might be helpful. Here’s the description of the frame selection from a paper on a lucky imaging system:
The frame selection algorithm, implemented (currently) as a post-processing step, is summarised below:
- A Point Spread Function (PSF) guide star is selected as a reference to the turbulence induced blurring of each frame.
- The guide star image in each frame is sinc-resampled by a factor of 4 to give a sub-pixel estimate of the position of the brightest speckle.
- A quality factor (currently the fraction of light concentrated in the brightest pixel of the PSF) is calculated for each frame.
- A fraction of the frames are then selected according to their quality factors. The fraction is chosen to optimise the trade- off between the resolution and the target signal-to-noise ra- tio required.
- The selected frames are shifted-and-added to align their brightest speckle positions.
If you want all the gory details, the best place to look is probably the thesis the same author wrote on this work. That’s available here PDF warning.
Yeah, that’s fair. I don’t think any lines have been crossed (yet) but the tone in the thread is certainly veering close to it. It’s also possible I missed a comment. Please don’t hesitate to report any uncivil or otherwise rule breaking comments.
Hi there. In the future please report any answers that don’t provide credible sources, as they’re in violation of rule 9.
Per rule 9, can you provide a credible source for your answer?
Any data is sent at or below the speed of light. Solar storms are charged particles (mostly protons) being ejected from the sun and eventually hitting the earth’s magnetic field, causing disruptions in the field (and potentially cool auroras).
Since these storms are just particles traveling from the sun to the earth, they travel slower than light speed, so our distant sensors can warn us in advance at/near the speed of light. This won’t work if the sun were to instantly disappear or change color though, that information would travel at light speed and the probe signals would arrive at the same time.
You are not being singled out. I’ve given the author of the other comment a warning with the opportunity to fix the rule violation with an edit, same as you. In both cases, the comments will be removed if they aren’t addressed in a reasonable timeframe.