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Evaporating black holes and the Vaidya metric
I've read that a distant observer watching matter fall into a black hole will see the matter get closer and closer to the horizon but never reach it. At the same time, the black hole is producing Hawking radiation and will vanish in a finite amount of time. Therefore, the observer should see the black hole vanish before they see the infalling matter cross the horizon. If the observer, the infalling matter, the velocity of the infalling matter, and the center of the black hole are collinear, then the final flash of radiation that the observer sees will pass right through the infalling matter. This implies that, before (from the perspective of the infalling matter) the infalling matter reaches the horizon, the mass will disappear, the horizon will disappear, and the infalling matter will end up in flat spacetime rather than cross any horizon.
The Wikipedia article https://en.wikipedia.org/wiki/Vaidya_metric gives an equation relating coordinates to distances (equation 6 on the current v
A question for the Physics communities
I think I need to rephrase this question. I'll post again in a few days.
... Hear me out, okay?
Back in 2000 I took my first solo, out of state trip, to meet an online friend. When I got off the bus, she greeted me, and let me know that we had to go stop by her friends house on the way back.
She was Wiccan and needed some Spiritual guidance because the night before she saw a black portal open up in the corner of her room that was giving her really bad vibes.
It wasn't my thing, but I never discounted it. Maybe it was real, and if nothing else it's just how her mind is rationalizing things.
But I guess my question is: Does the Scientific Method rule out the possibility that a "real" portal appeared in her room?
Taking wave function probability into account and the absense of data from the room, is it fair to say that the scientific method doesn't rule out the black portal being real?
Looking for black and white answers if possible, but I'd also love to hear your reasoning~
Are the theories of Relativity rational or just more pseudoscience?
For those that have taken the blue pill, here is an introduction to the thinking that comes from taking the red pill. Which version makes most sense is up to you to decide. But don't automatically jump to the conclusion that your Einstein version is all that solid as a reasonable way to understand reality. Its clearly not, well that's the only possible conclusion that Dave and the AI Chatbot came to. See if you can find any errors in their logic if you believe that the Physics of Einstein is rock solid or even rational. The series of 5 ebooks is available for 99 cents on Amazon, and free on other book distributors until September 2024. The subjects covered are SR, GR, Spacetime, Speed of Light e=mc2, and some of the most famous experiments, all of which are found to be nonsense. Google "Dave vs Hal 9001"
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Is it possible to determine the percentage of the gravitational force at a specified distance using only the geometry of the planet?
Example: The ISS at ~420km altitude "weighs" about 90% of what it would on the Earth's surface.
Is there an equation using only geometrical values that would give you this info?
Edit: Answered!
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High-quality video by an underrated channel.
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If you haven't played the games above I recommend you do, half are free.
What are some other cool physics games you guys know of, whether simple or in-depth, big or small, educational or not?
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Question about wave/particles interacting
Does it make sense to ask: How hard does a photon hit an object?
Does the waviness of photons make that a dumb question? If it does then what is a more correct way of conceptualizing the interaction of a photon with, for example, a light receptor? Or does the analogy in my head of a ball hitting a wall fairly represent the behavior of a photon at the moment of impact?
