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Optics is the study of light, and its interaction with matter. It includes topics such as imaging systems, fiber optics, lasers, quantum optics, and more.
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How does light bend around my finger tip?
When I close one eye and put the tip of my finger near my open eye, it seems as if the light from the background image bends around my finger slightly, warping the image near the edges of my blurry ...
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What is Chirped Pulse Amplification, and why is it important enough to warrant a Nobel Prize?
The 2018 Nobel Prize in Physics was awarded recently, with half going to Arthur Ashkin for his work on optical tweezers and half going to Gérard Mourou and Donna Strickland for developing a technique ...
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Why do we actually see the sun?
I haven't yet gotten a good answer to this: If you have two rays of light of the same wavelength and polarization (just to make it simple for now, but it easily generalizes to any range and all ...
user22862
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Could Legolas actually see that far?
The video “How Far Can Legolas See?” by MinutePhysics recently went viral. The video states that although Legolas would in principle be able to count $105$ horsemen $24\text{ km}$ away, he shouldn't ...
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What is an "attosecond pulse", and what can you use it for?
The 2023 Nobel Prize in Physics was announced today, and it was awarded to Pierre Agostini, Ferenc Krausz and Anne L’Huillier, for
“experimental methods that generate attosecond pulses of light for ...
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Why are the windows of bridges of ships always inclined?
What is the reason that the windows of ships' bridges are always inclined as shown in the above picture?
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Why do wet objects become darker?
When something gets wet, it usually appears darker. This can be observed with soil, sand, cloth, paper, concrete, bricks...
What is the reason for this? How does water soaking into the material ...
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Why are most metals gray/silver?
Why do most metals (iron, tin, aluminum, lead, zinc, tungsten, nickel, etc.) appear silver or gray?
What makes copper and gold have different colors?
What atomic characteristics determine the color?
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Why is glass transparent?
Once I asked this question from my teacher and he replied "Because it passes light.". "And why does it pass light?" I asked and he said, "Because it is transparent.".
The same question again, Why ...
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How can we see an atom now? What was the scale of this equipment?
I've just seen this on the news - Single Trapped Atom Captures Science Photography Competition's top prize.
Credit: David Nadlinger via EPSRC
I am not a Physics major but I believe I do know the ...
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Seeing something from only one angle means you have only seen (what?)% of its surface area at most?
Is there a logical/mathematical way to derive what the very maximum percentage of surface area you can see from one angle of any physical object?
For instance, if I look at the broad side of a piece ...
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Why do metals only glow red, yellow and white and not through the full range of the spectrum?
Why don't metals glow from red to yellow to green to blue etc.? Why only red, then yellow and then white? Shouldn't all wavelengths be emitted one by one as the temperature of the metal increases?
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What really causes light/photons to appear slower in media?
I know that if we solve the Maxwell equation, we will end up with the phase velocity of light being related to the permeability and the permittivity of the material. But this is not what I'm ...
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Can photons be detected without being absorbed?
I am thinking about a detector that would beep if light passes through it. Is it possible?
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Why does a rubber band become a lighter color when stretched?
I was stretching a pink colored rubber band, and I noticed that the longer I stretch it, the lighter the pink becomes.
Why does this happen?
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