Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: thedoc on 10/10/2016 15:53:02
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Sarvotham Pai asked the Naked Scientists:
I was going through some videos on sonic boom and was intrigued.
When a fighter jet travelling faster than speed of light approaches us, we cannot hear it, the moment it's passing us we hear the sonic boom and once it's moved away we just hear the regular jet engine noise.
If we were to extrapolate this to light waves rather than sound waves how would a similar scenario play out.
Hypothetically, if an object is travelling at speed of light and approaching us, we should not be able to see it. The moment it passes us we should experience a "Visual boom" (I imagine this to be an intense flash of light) and once it's moving away from us we should be able to visually see that object.
Just penned down my thoughts and like to know your expert opinion. An animated video explaining this concept would be great if possible.
What do you think?
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it is possible for an electron to pass through a material faster than the phase speed of light through that material. You get a light cone similar to the sonic boom.
Look up cherenkov effect.
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The Cherenkov effect causes the classic blue glow you see around the core of a nuclear reactor. (And I'm sorry to disappoint Simpsons fans - but it's not green.)
See: https://en.wikipedia.org/wiki/Cherenkov_radiation
Some early searches for hypothetical Tachyon particles looked for Cherenkov radiation in a vacuum. They didn't find any. This is not so surprising, because by the time these imaginary particles reached Earth after traveling through the vacuum of space, they would have lost so much energy through Cherenkov radiation that they would have sped up and become undetectable.