Strange

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Everything posted by Strange

  1. Another solar-powered, propellentless craft described here: https://www.universetoday.com/142894/lightsail-2-is-sending-home-new-pictures-of-earth/
  2. Why are you asking? Or, more specifically, why are you asking me?
  3. ! Moderator Note As the OP has been given a a few days holiday from the site, this thread is closed. (Also because it is nonsense.)
  4. The water would rush to fill the empty space. This would be an extreme form of cavitation: https://en.wikipedia.org/wiki/Cavitation There is no negative state, in terms of mass or energy (or the presence of matter). No. A (perfect) vacuum is zero mass (and energy). There is nothing less than that.
  5. There is no connection between them. The uncertainty principle is about a limit to which things can be measured, even without any effect from the observer.
  6. ! Moderator Note If you have a new idea, please feel free to start a new thread in Speculations. If you want to ask questions to clarify your understanding, please start anew thread for your questions. Thank you.
  7. ! Moderator Note OK. Thread closed I’m glad to see you agree that the science is correct
  8. ! Moderator Note Your incredulity is not a valid argument. Unless you can show an error in the mathematics this thread will be closed.
  9. You are misusing the word "science". It is like saying "science is pink, because it is a flower that grows on a plant with thorns (which, by any other name, would smell as sweet)". THAT IS NOT WHAT "SCIENCE" MEANS. If you are going to make up your own meanings for words, then this whole conversation is pointless. Science is a human activity, invented by humans. No. It is up to you to provide a proper reference, in other words, a written document. Can you read? I would start with a dictionary. And, quite obviously, you have not studied anything. That is the wrong definition of science. You invented that definition. It is wrong. It is like Alice in Wonderland:
  10. I don't have any feelings about it one way or another, whether it connects to the cloud or not !
  11. It isn't always. Many systems use multiple antennas so they can do beam-forming so that they can transmit and receive in specific directions. This make them much more efficient. For example, Wi-Fi uses this; I don't know if cell phones do yet, but there is no reason why they couldn't, in principle.
  12. Black hole. Event horizon Gneeral relativity The vacuum would create no gravitation (because it has no mass). The cubic foot of matter would create a gravitational field depending on its mass: 1 cubic foot of hydrogen has much less mass (2.5 grams) than 1 cubic foot of osmium (640 kg). If it is a gas at higher pressure than its surroundings, Male. But not in general. Massive objects attract one another. Although it is not quite that simple. A completely even distribution of mass will either expand or contract. It depends on how it is measured. It is only negative if you use a relative pressure gauge. When I did a little bit of vacuum physics, a perfect vacuum was a pressure of zero. The pressure we actuallyachieved would be positive.
  13. Definitely. Just leaving the lights on and blocking all the windows but one would generate more force.
  14. Jesus H Christ. Still? THE CRAFT IS NOT MOVED BY THE FORCE ON THE WIRES. How many times does this need to be explained?
  15. I assume you mean ST (string theory) rather than SR (special relativity) ? It is true that string theory does not make any currently testable predictions. In that sense it is not falsifiable. I would reserve unfalsifiable for the stronger sense of "not falsifiable in principle"; i.e. whatever technology or techniques are used. Examples are solipsism or last-Thursdayism or Creationism. I would define string theory as untestable rather than unfalsifiable. There have been examples of theories in the past that could not be tested at the time. But later advances in technology (or a better understanding of the theory) allowed tests to be developed (which either confirmed or falsified the theory).
  16. OK. But this is a science forum, so guesses and making stuff up don't really count for much.
  17. Please provide a reference for the. (I am genuinely curious what you are talking about)
  18. Is that supposed to be an answer to my request for evidence? The fact that humans can communicate across distances is not evidence that there are other intelligences in the universe, nor that they are communication with each other.
  19. Well, if there is no physical reality then there is nothing. But apart from that, mathematics does not necessarily have any connection to physical reality. I may have misunderstood what you meant here. What do you mean by "mathematical theory"? I assumed you meant a mathematical theorem; ie. a mathematical questions that can be proved (or disproved) using purely mathematics. But if you meant a theory about physics that uses mathematics (such as General Relativity or Newton's theory of gravity) then it is confirmed (not proved) by experimental observations. And, more than that, it is not enough to just predict that "light will curve round the Sun" (for example). You have to predict how much the light will curve; the reason that GR was confirmed is that it predicted a different amount of curvature than Newtonian gravity (not just "some" curvature)which was then measured and confirmed. In other words, you can't do physics without math.
  20. No you can't. Proofs are not usually accepted until they have been checked several times. And often recreated in different ways. Then either the proof is wrong (and rejected) or sometimes the errors are corrected and the proof still stands. Using mathematics. That is not mathematics.
  21. I would say that the opposite of a vacuum is a volume of space full of matter. A black hole is (or can be) surrounded by vacuum. Other way round really. GR explains gravity and also explains why empty space expands and why black holes exist.
  22. You said "in 50 years" so I imagine that battery technology will have advanced significantly by then. Also, mobile phones can already use mesh networks. They use a lot less power to communicate with another nearby device than a distant cell tower. Maybe. But as we don't know what new physics might be discovered in the next 50 years, the question is meaningless.
  23. Wrong. If you mean "common sense may be wrong" then, obviously, yes. That is why science doesn't use it. That is not what the word "science" means. Go check a dictionary. Science is a human invention.
  24. I think you should read back. The force on the craft is not the same as the force on the wires.