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Strange

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Everything posted by Strange

  1. But approximately 100% of the helium of the universe is primordial.
  2. And helium. And a little lithium.
  3. I would say that you can't say it has changed because you don't know what it was before you measured it (and it may not even have a value until you measure it).
  4. Explaining why there is no communication involved is tricky. But, basically, all we can say is that the measurements made by two people, A and B, are correlated in some way. So, if Alice measures spin up (for example) then Bob will measure spin down. And vice versa. So let's imagine that Alice and Bob each have one of a pair of entangled particles. If Alice looks at her particle she has a 50% chance of seeing spin up or spin down. And Bob has a 50% of seeing spin up or spin down. Imagine Bob looks at his particle. It could be spin up or spin down. Let's say he sees spin up. What does that tell him? Well, it tells him that if Alice has already looked at her particle, then she saw spin down. Or, if she hasn't yet, then it will be spin down when she does. Now imagine Alice looks at his particle. It could be spin up or spin down. Let's say she sees spin up. What does that tell her? Well, it tells her that if Bob has already looked at his particle, then he saw spin down. Or, if he hasn't yet, then it will be spin down when he does. So they both know what the other has seen / will see, but they can't use this to send any information. They can exchange information "classically" (at no more than the speed of light) and end out that their results were always opposite. But they can't transfer any information knowing that. Indeed. There is no such thing as absolute simultaneity. That means that one observer might see Alice look at her particle before Bob, while another observer might see Bob look at his first. (And another might seem them look at the same time.) But you can take that into account if you want to calculate how much time elapsed between the two events. So it isn't directly related to entanglement. (Note that Einstein never really accepted that part of quantum theory.)
  5. Theory says it happens at the same time (in other words, time does not appear in the description of what happens). People have attempted to do experiments that measure any delay (I don't know the details off the top of my head) and found that the "speed of communication" (note: there is no communication) is at least 10,000 times the speed of light (again, can't remember the exact number, will try and find it). So as close to "the same time" as we can measure. Edit. This is the paper: https://arxiv.org/abs/1303.0614
  6. Sounds interesting. Einstein had obviously realised what he needed to capture mathematically before he understood that tensors were the best tool for the job. I have probably mentioned this before, but John Baez has written a great introduction to the concepts behind the Einstein equations using relatively simple math: http://math.ucr.edu/home/baez/einstein/
  7. I bet Einstein started out thinking that. "How hard can it be, ja?" After a year or so of work, he realised it was getting pretty complicated. "Sheisse! Grossman was right! I need to learn about tensors."
  8. Does this help: https://en.wikipedia.org/wiki/Priority_encoder Actually, it might not because the first paragraph is incomprehensible. But the second paragraph is clearer. Basically, it has a number of input bits which are in priority order, and it tells you the highest priority bit that is set. I'm afraid I am not going to try and work out what it does in that system. Presumably it chooses the next person to be processed.
  9. ! Moderator Note You know those rules you agreed to when you signed up? How about sticking to them. If you have something to discuss, post it here on the forum
  10. ! Moderator Note No one is going to "take your theory". That is not how science works. If you are not interesting in discussing this on a discussion forum then this thread is closed. ! Moderator Note OK. I missed that. I will reopen the thread if you want to discuss this.
  11. ! Moderator Note One thread per topic. Thank you.
  12. ! Moderator Note If you don't have a mathematical model, you don't have a theory. Or even a hypothesis. The Speculations forum requires you to support your claims, for example with evidence. If you are not able to do that then this thread will be closed.
  13. I can imagine invisible pink flying unicorns. Can it be? ! Moderator Note Moved to a more appropriate location
  14. The original question was posted 21/2 years so they have probably given up on us by now.
  15. It hasn't been retracted. I'm not sure I would say it is definitely ruled out. They are probably mistaken, but it is an interesting result that might still tell us something new.
  16. I don't think you understand how science works. Some people made some measurements. They suggested one reason for the data could be that the universe was not expanding at the same rate in all directions. If you read the paper again, they also pointed out that there are several other possible explanations. Ethan's article is pointing out that these other existing explanations are more likely to be the case. In particular, he casts doubt on their assumption of a tight relationship between temperature and luminosity (as I pointed out when I posted that link before). Note that science is all about possibilities and what seems to be most consistent with the evidence. It is not about truth. And not all scientists agree about what the best explanations are. From the article linked from your second link: This finding could be a sign that the universe is actually “anisotropic” ... This possible evidence for anisotropy ... Doing so allowed the researchers to estimate the cluster’s x-ray luminosity—and therefore its distance allowed Migkas and his colleagues to probe potential deviations in the universe’s rate of expansion thus potentially closer or farther away than expected "We managed to pinpoint a region that seems to expand slower than the rest of the universe and one that seems to expand faster,” Migkas says Therefore, the situation is still vague. Perhaps, somewhere in the intervening eons Alternatively, the universe might not be lopsided at all The most obvious explanation, of course, would be that the apparent asymmetries in cluster spacing are because of flaws in the data or their analysis Such inconsistencies suggest correlations between a galaxy cluster’s x-ray temperature and its luminosity are not as clear-cut as researchers would prefer there are other potential problems to deal with Riess adds. “That seems suspicious!” David Spergel ... also suspects faults in the cluster-based measurements “This is a paper that is very important if [it is] true but very unlikely to be true,” he says. They are now looking for further hints of galaxy-cluster anisotropy It would be great if we knew https://www.scientificamerican.com/article/do-we-live-in-a-lopsided-universe1/ Do you get the idea? Nothing is certain, everything is conditional, it all needs further research,
  17. No, it is purely due to the invariant speed of light.
  18. ! Moderator Note Please keep all your questions about computer architecture in this thread. No, registers are not part of memory. They are storage inside the CPU. They are typically 1 word wide and used for arithmetic and logic operations on data. Instructions are not usually stored in registers. They are read from memory and executed. Instructions do things like: read data from memory into registers, write data from registers to memory, move data between registers, perform operations on data in registers or jump to another instruction.
  19. Note that it is a large amount of energy released over a very short time. It is a bit like comparing a lightning flash, which releases a large amount of energy (about a billion joules) in a very short time (around 1 millisecond). This is equivalent to 1 trillion 1W LED bulbs shining for the same amount of time. Or one of those bulbs shining for 32 years. His estimate is, I think, based on about 10% of the mass of the black hole being converted to gravitational waves (which is roughly what we have seen so far); say 50 million solar masses. So that is massive amount of energy being released over a very short time (a few hours). But stars burn very slowly, and only convert a tiny fraction of their mass to energy. So it takes billions and billions of starts to release the same amount of energy. The difference is that the stars can keep releasing that tiny trickle of energy for billions of years.
  20. Who says it would be more powerful than all those stars together?
  21. Gold, silver, helium and a few other elements occur in their elemental form and don't need water to be present. They don't. Both of those statements are false. If there were no oxygen, then there would be no water. But note that both water and elemental oxygen were quite late arrivals on Earth. You are going to end up with a very boring periodic (and wrong) table.
  22. As I say, it would be much more productive to ask questions instead of making stuff up. You will a more positive reaction and helpful replies. The equation for length contraction is: [math]L =L_{0}\sqrt{1-v^{2}/c^{2}}[/math] where L0 is the original length, v is the relative velocity and c is the speed of light. Note that you will see the passing object get shorter. But a passenger on that moving object will see you get shorter.
  23. ! Moderator Note If you are hijacking your own thread with irrelevant nonsense, I think we are done here. Do not bring this subject up again.
  24. So explain how your naive restatement of the blindingly obvious solves the mathematical conflict between GR and quantum theory; presumably you are an expert in both?
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