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bio website lightandmatter.com
location Fullerton, California
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visits member for 3 years, 9 months
seen May 1 at 2:14

I teach physics at Fullerton College, a community college in Southern California. I have an undergrad degree in math and physics from Berkeley and a PhD in physics from Yale. Back when I was doing research, my field was experimental low-energy nuclear physics.


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comment How come some people are claiming that the Big Bang never happened?
This doesn't address the question.
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comment Energy Required to Rip Spacetime
It sounds like you're referring to topology change. The classic paper on this topic is by Geroch, adsabs.harvard.edu/abs/1967JMP.....8..782G . Here is a more recent discussion: arxiv.org/abs/gr-qc/9406053 . Geroch showed that there must be either CTCs or a violation of the weak energy condition.
Dec
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comment Why are electromagnetic waves not able to pass through a hole with a diameter smaller than the wavelength?
But if they are close together...closer than the wavelength of the radiation...then they represent two coherent sources whose amplitudes add. So you get FOUR times the power. Diameter-to-the-fourth. (Because it doesn't matter if the two holes are merged into one.) Two mistakes here. (1) Two holes side by side do not constitute a hole with twice the diameter. (2) If power goes like the fourth power of the diameter, and you double the diameter, then you get 16 times the power, not four times. For a correct explanation of the exponent, see the questions that this question duplicates.
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revised Why are electromagnetic waves not able to pass through a hole with a diameter smaller than the wavelength?
remove quantum-mechanics tag; add diffraction
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comment Why are electromagnetic waves not able to pass through a hole with a diameter smaller than the wavelength?
duplicate of physics.stackexchange.com/q/141556 and physics.stackexchange.com/q/141562
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