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About Halc

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  1. Thanks Markus! +1 You seem to be the only responder that at least understood the question. So I'm going to ramble a bit, part of which probably isn't worded as precisely as it should. 'Gravitation potential' is a local concept then, relative to say a system that is stationary like Earth, where one can speak meaningfully of the relative potential difference between sea level, geosync orbit, and the hole we've hollowed out in the center, but all potential is relative to some reference (sea level say) and involves whatever components (Earth, sun, galaxy) we decide to include in our ca
  2. You're not doing the mathematics at all. Sure, I illustrated infinite potential even with the linear and planar case (even Newton knew this), but the uniform distribution of mass in 3D is even worse. Your -GM/r is for a point mass (or spherical) from which you can distance yourself. Yes, there is finite potential for any one finite mass, but the mass of the universe is not finite and not at some fixed radius. OK, we can do it another way using Newton's shell theorem. At a large enough scale, matter is distributed uniformly in the universe so the shell theorem is valid. Imagine a th
  3. I've not seen this question posed before, and I've approached the question from different perspectives yielding different answers. What is the difference in gravitational potential from here on Earth to zero potential (the hypothetical potential of an empty universe)? From a mathematical standpoint, it seems to be infinitely negative. The escape velocity from a 1D infinite length rod drops off at 1/r, and so if gravity is X at the rod, it is 1/2x at twice the radius of the rod. The series ∑ 1/n does not converge. With a 2D infinite sheet, gravity does not fall off at all with dista
  4. The dandelion in my front yard is an atheist. It doesn't believe the Earth is flat either. It's not exactly a remarkable claim to say something lacks a given belief, or for that matter, the capability of any belief.
  5. Indeed. A pair of plumb bobs will not be parallel on Earth, but will be in an accelerating ship. In the inertial case, a plumb-bob in the no-gravity case will not point anywhere, but off-center in an orbiting space station, they will. So there are very much differences. The most basic test: Create a 3D arrangement with 4 balls (stationary relative to our small orbiting lab) arranged in a tetrahedron (in a vacuum so air currents don't move them around). The movement of the balls will show the direction of the source of gravity, or at least the axis of it.
  6. There are still tidal effects with acceleration. An accelerometer at the front of a rockets reads less than one at the rear. The difference is negligible for the tiny acceleration of our rockets, but if you really jacked the g forces and made the rocket long (and strong) enough, the figures would be very different. Yes, the air moves to the rear, just like helium balloons tend to move to the front of a car when it is accelerating. If the accleration acts on all particles of the ship (say due to a large mass passing in front of it), then the passengers will feel no acceleration at
  7. I was speaking of the first trial where the vote went straight down party lines.
  8. The question doesn't seem to be a scientific one on the surface, but rather a philosophical one. He's asking the wrong people. It is akin to asking if the combustion of a candle can continue after the candle goes out. Can a process continue after the cessation of the process? Bufofrog gave a great reply to that. If 'human consciousness' is defined/modeled in a way outside of methodological naturalism, then it outside of the methodology of modern science. Still, I am of the opinion that it can be treated as a black box and essentially reduced to the candle case.
  9. Like the last impeachment trial, there seemed to be a complete lack of correlation between the outcome and the evidence presented. The crime upon which the vote was based was the crime of belonging to the minority party, and Trump was rightfully acquitted of that. They've threatened, before the inauguration even, to impeach Biden as soon as they could, not for any crime other than again, being a member of the minority party. Those plans have been sidelined since Biden is no longer guilty of that crime, at least not for the next 2 years. I am crushed by the fact that such matters are no
  10. Even as a pre-teen I wondered these questions about the six million dollar man. Here he can lift a truck with this bionic arm, but no explanation as to how that force gets transferred through his torso to the bionic legs below. He'd need an I-beam from shoulder to hips to do that, and said beam would prevent any ability to move like a normal human. The arm wrestling thing (6 vs. 7 million dollar man) had similar issues. From where comes the reaction force to this theoretical insane pressure/torque between the two guys? I was a kid and couldn't handle the blatant disregard for physics su
  11. But the sister cells are just as old. Excepting cells that are manufactured (*), all bad (damaged, stressed) cells are replaced by mitosis of the remaining ones, all of which are essentially as old as you are. Maybe I'm wrong about that. Hardly an expert here. The DNA is also replicated this way, not manufactured from scratch, so all the DNA is effectively as old as you are,. Neurons can't just split since their connections cannot be reproduced, so they're intended to exist without replacement after their initial allotment is complete some months after birth. * Blood is a nice exampl
  12. It's not a waste of time for the reasons posted above. You must realize the reason for the stance, which might be (as mentioned above) to promote critical thinking as opposed to just assuming the answer you've been taught. It also might just be to push people's buttons, in which case engaging is considered 'feeding the troll'. The moon thing seem unnecessarily complicated and dependent on how one orients a camera. How about the fact that I can be talking to somebody and one of us in in daylight (or can see the moon at all) and the other not. If Earth were flat, it would be daylight every
  13. Entanglement conveys no information. The sources of this pop article seem not to know that. Saplakoglu writes: It just doesn't work like this. A pair of particles unmeasured are not meaningfully in any state at all. If measured, they're not entangled. Some logical fails follow: No, it is not at all like placing 100 coins with 50/50 mix. That implies a measurement already taken. It's more like having 100 unknown coins and measuring 99 of them gives zero clue as to what the last one will be. Entanglement is like slicing 100 coins in half and sending the 100 halves to
  14. Sounds like a stroboscopic effect. Have you tried it in natural or incandescent light? A spinning ring/disk will not reverse direction, but the spin goes anti-clockwise and the precession of the primary axis turns clockwise and the latter becomes more noticeable as the spin flattens.
  15. If the cube is floating (not resting on anything), then it must displace its mass in water (just like a floating boat displaces its mass in water). When it melts, it still displaces its mass in water so no change in water level. All floating ice has about 10% of its volume above the surface since that's the density difference. If it is resting on the bottom of the glass, some of the weight is supported by the glass and not water, so the water level would be low and would rise as the ice melts. This rise ends once the ice stops resting on anything. If the ice is held under the water
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