geordief

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1. A different way of looking at the trampoline analogy

Because it is spacetime that is curved and not space?
2. A different way of looking at the trampoline analogy

Yes ,it is intended to be an analogy. But analogies can perhaps be useful as a way of getting a clearer understanding of the actual phenomena or just encouraging further inquiry. So, can some analogies be better than others? The trampoline analogy has the fault ,if taken literally**of mistaking an effect if gravity for gravity itself. If that is disregarded it is a lot "catchier" than mine -maybe too catchy for it's own good. **of course students should be repeatedly warned that it is just a flawed analogy (as all analogies intrinsically are)
3. A different way of looking at the trampoline analogy

One of the main arguments against the trampoline analogy for spacetime curvature is that the heavy object distorting the fabric of the trampoline/spacetime fabric itself relies on gravity to act ... Suppose we just have two bodies ,one of which is a source of mass/energy and they are connected by a geometric line that is marked off in equal lengths of spacetime distance. There is a tension between the two objects (and so along the geometric line?) for the "simple" reason * *that the two objects have in principle a common source at the beginning of the universe ,whatever that looked like. Going back to the two objects,as time progresses the massive/energetic object "pulls on " the geometric line representing spacetime and "reels it in" like a measuring tape that springs back into the body of the tool. But the line is held at the location of the second body and ,moreover is elastic . And so the spacetime intervals written on the geometric line are stretched on the side of the massive body and this stretching is continues all the way along the geometric line as far as the second body,with the distortion from the ideal even spacing greatest in the immediate vicinity of the massive body ,but still existing (propagating?) as far as the second body ,or indeed to infinity if that is where the second body is. This is different from the trampoline analogy in the it just deals with one spatial dimension (at a time). The idea occured to me as I have been forced to wear compression stockings for now and when you pull them up the leg it looks a bit like stretching a trampoline or spacetime fabric in action Also ,in the What is Gravity thread a few of you are talking about whether spacetime curvature can cause mass or vice versa. In "my" analogy the mass can "ingest" spacetime and so it "causes" it. And the stretchy geometric line (spacetime) cause the second object to move relative to the massive object. **well,I think both these objects have a prior relationship and so a "historic" connection in that sense
4. What is the nature of our existence?

Do I sound like an extreme monist? And you would be a mainstream monist ,perhaps? I am only slightly familiar with these concepts https://www3.nd.edu/~maritain/jmc/etext/psych023.htm#:~:text=Dualism teaches that Mind and,one and the same Reality. but ,from the link there seem to be quite a few variations... I think I would be attracted to what you say is not the case I think consciousnesss could be extensive in the same way as a particle extends into its field according to QFT. (of course I am waffling)
5. What is the nature of our existence?

I think more along the lines that your consciousness is those experiences. There is nothing "hands off" about what I think of as consciousness.It is entirely immersive , athough there is an illusion of an "internal observer". which is just a facet of our consciousness.
6. What is the nature of our existence?

You are thinking of a coma? So if you have an experience where "nothing could be better" (as in the oft quoted line"it was bliss that day to be alive" ) and this is followed by the depths of despair (perhaps as a result of a medical condition) your consciousness does not follow any direction? In the former experience all your days lie ahead of you in anticipation and in the later there is no tomorrow. Is your consciousness diminished or altered?
7. What is the nature of our existence?

So ,if we lose a hair off our head we loose (just change?) a bit of our consciousness(as well as when there is a change in the environment such as the sun going behind a cloud)? Can we increase or decrease our amount of consciousness or is it just redirected/reoriented? Do emotions affect our consciousness?
8. What is gravity?

Can we bottle (or just create) spacetime curvature and thereby create (or annihilate) mass? That might be a causal relationship.
9. Growing forests double quick

I assumed they would be thinned at an earlyish stage(no idea how they develop after that) Here is their website https://www.facebook.com/KBtreegang/ There is not much specificity regarding the aims of the project,but increasing local bio diversity seems to figure as one of the main aims and the fast rate of initial growth attracted the attention of the national broadcaster,I guess. Yes I have read that some plants are able to attack the roots of competitors chemically.I am forever weeding the scutch from my strawbs for that reason but without noticeable benefit.
10. Do you feel a lot better by using a bigger screen phone?

That's true ,it was a female saleswoman. The logic breaks down there.
11. Do you feel a lot better by using a bigger screen phone?

It was strange when I went to the Vodafone shop this week with the intention of buying a new phone and ,except for really expensive models there was nothing they could offer me under 6 inches. Looking online ,I had no more luck I am pretty surprised that these large sizes are what people seem to want .. Yes I think IPhones seem to be available in smaller sizes than eg Samsung.
12. Growing forests double quick

https://www.rte.ie/news/2024/0308/1436684-trees-climate/ "The Tiny Forest concept was pioneered by a Japanese botanist, Akira Miyawaki. He pioneered a special method of planting and ground preparation that can be used to grow forests ten times faster than a typical forest (which usually takes 200 to 300 years" "Usually up to five saplings are planted for every square metre and as a result, the trees are forced to grow upwards for sunlight instead of spreading outwards"
13. Do you feel a lot better by using a bigger screen phone?

It is difficult to get a small one.I got this by going to a reconditioned phone website. It is 2017 and a 4 inch screen. There was an awful problem getting a battery for it ,though (the battery it came with was on its last legs) as they don't ship them in aircraft any more and I had to visit phone stores around town to look for old batteries from broken phones. I prefer these smaller screens for convenience even though they are no doubt harder to read.
14. Alabama court - "Embryos are people"

The universe?
15. Alabama court - "Embryos are people"

Not when I search. They don't batter embryos in Alabama?(a bit deadpan)
16. Alabama court - "Embryos are people"

Woody Allen might need some kind of a disclaimer before screenings of his "All you Wanted to Know about Sex but were Afraid to Ask." "No human beings were massacred or demeaned in the making of this movie"
17. How do scientists explain RF waves traveling, without a medium?

@Genady Don't worry.I generally /often just quote content rather than the particular poster. Feel free to jump in .
18. How do scientists explain RF waves traveling, without a medium?

If the vacuum is filled with quantum foam (a big "if" ,as I don't understand what that means) could an object's speed/velocity be referred to different locations in that quantum foam? Does the term "location" not apply ,perhaps wrt quantum foam? Said in another way ,could the quantum foam be considered to be a medium?
19. TFG or That Florida Guy? Either way, can the GOP win in 2024?

Seems a lot but the prosecution's case was that it was representative of the profit he made on his misrepresentations. I think he should be fined extra just for being who he is. We should give him the witch hunt he claims he is getting. (Has he claimed Brit Ekland was begging for it yet?)
20. Understanding ancient scrolls from Herculaneum

https://www.bbc.com/news/science-environment-68221243 "Three students have won a \$700,000 prize after using AI to read a 2,000-year-old scroll burnt during the Mount Vesuvius eruption in 79AD." This is a great story .A few years back there was talk as to whether these (or similar scrolls) would be legible and now there seems a lot of optimism because of new technology available .
21. Today I Learned

I normally go around wearing wellies and a Barbour Jacket (but only drive a small Toyota Yaris ) The man at the shop checkout did point out that it was a cool outfit.
22. Today I Learned

https://www.bbc.com/news/world-europe-68196828 The price went up a bit. Parking in Paris for so called non resident ambulato-mechanical onanists has now tripled.
23. Inquiry : Spacetime Ruptures and Bidirectional Time

Do you think Susskind was giving a pop-sci explanation? Would that not be frowned upon in the formal setting of what I assumed was a lecture (at Stanford ,I think)? I think in this case he did preface his remarks by saying most would disagree.
24. Inquiry : Spacetime Ruptures and Bidirectional Time

I looked at the Susskind video.He seems to be saying that adjacent regions of space contain particles (virtual particles,was it?) that are entangled. So the property of space being entangled (if I understood the lecture) was its property of containing entangled particles close to either side of a line dividing it.(not just at the event horizon of a BH but generally) And I think Susskind did refer to this as "space being entangled" I found that extraordinary and I think perhaps most physicists may disagree with that (Susskind's caveat) but ,if that is accepted then he goes on to say that that might violate " entanglement monogamy"
25. Could we observe the present ?

You have to be specific. Until you do I say that this is incorrect.
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