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31.10.2020, 20:03
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| | | Quote: | |  | | | Summary- Lots of people have advanced every branch of physics over the past few decades
- Even more people, including quite a few on EF, make use of these new discoveries and developments
- Almost everybody is aware of the rapid growth of knowledge in physics and its application to solution of problems
- Some bloke on the internet called Flying Kite isn't.
Suggestion- Let's get on with our lives and let the non-believer(s) get on with his/hers.
| | | | | ...I am totally agree that we progressing at high speed...
...it is because of engineering that use theories that was elaborate in Einstein time or prior...
...tell me about any new mechanic laws?... | Quote: | |  | | | Since the practical utility of new physics seems to be a bee in your bonnet, here are some useful bits of physics discovered since Einstein:
- Semiconductor physics
- Theory of turbulence
- Theory of polymer physics (de Gennes Nobel prize)
- Theory of liquid crystals (ditto). Some idiot journalist said that he had invented LCD watches. All of de Gennes work was useful. See also his work on wetting of surfaces and drop formation.
- Theory of fractals and experiments too. Mandelbrot first worked on noise on telephone lines for IBM.
- Chaos theory and experiments.
There are plenty more. | | | | | ...all of those theories have been formulated in Einstein time...fractal geometry are problem of mathematics, solved by mathematicians...
Last edited by roegner; 31.10.2020 at 20:19.
Reason: Merging consecutive posts
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31.10.2020, 21:18
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| | Re: Ask a Scientist | Quote: | |  | | | ...I am totally agree that we progressing at high speed...
...it is because of engineering that use theories that was elaborate in Einstein time or prior...
...tell me about any new mechanic laws?...
...all of those theories have been formulated in Einstein time...fractal geometry are problem of mathematics, solved by mathematicians... | | | | | This getting silly.
Reminds me of when I studied Physics and we shared a building with a Chemistry faculty and an Engineering faculty.
We were a small group so we all knew each other, we could always identify which strangers in the mens toilet were chemists (versus engineers) because they washed their hands first.
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01.11.2020, 00:58
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| | Re: Ask a Scientist | Quote: | |  | | | ...you didn't get what I was meaning about transfer of information...when photon is shut in space is hitting in his way a mole of hydrogen, that mole have an electron floating around, when that photon hit the electron, electron emit an photon encrypted with info from precedent photon and that is repeated many times until reach the receptor...
...is no empty space in whole universe, all spaces exists are filled with something, in 80% of cases with hydrogen, light from the stars to reach us use hydrogen as transportation... | | | | |
I guess you're referring to quantum electrodynamics / QED as being a mode of transfer for information (electrons absorbing and emitting photons). But in quantum teleportation, information is not exchanged via the interaction of light/photons and matter/electrons in the sense that it is transferred via QED. Teleportation occurs via entanglement, which in turn is now thought to occur via wormholes (Einstein–Rosen bridge).
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The quantum vacuum state does exist, though it does contain fluctuations of energy in the form of 'virtual particles' popping in and out of existence / particle annihilation. But I'm pretty sure the quantum vacuum does not contain hydrogen. | 
01.11.2020, 00:58
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| | Re: Ask a Scientist
As the drugs are wearing off, just wondering if the genetic modification of species by man could still be considered as part of natural evolution (after all, man is a product of nature).
E.g. Is an Iceberg lettuce an example of "survival of the fittest" or simply 'survival of the crispiest'?
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01.11.2020, 08:12
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| | Re: Ask a Scientist | Quote: | |  | | | This getting silly.
Reminds me of when I studied Physics and we shared a building with a Chemistry faculty and an Engineering faculty.
We were a small group so we all knew each other, we could always identify which strangers in the mens toilet were chemists (versus engineers) because they washed their hands first. | | | | | I read yesterday, coincidentally, that people indeed should wash their hands before and after. They also said not to press the flush with your finger tip but with your knuckle - easier to clean. Not to use the dryer either, cracks the skin and opens the door to germs. | Quote: | |  | | | As the drugs are wearing off, just wondering if the genetic modification of species by man could still be considered as part of natural evolution (after all, man is a product of nature).
E.g. Is an Iceberg lettuce an example of "survival of the fittest" or simply 'survival of the crispiest'? | | | | | There is not much natural in man-designed GM food. Survival in nature is often manifested by chemicals/strategies that prevent something from being devoured? But I am looking forward to expert's opinions on this!
Btw - how are you doing?
Last edited by MusicChick; 01.11.2020 at 08:58.
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01.11.2020, 08:50
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| | Re: Ask a Scientist | Quote: | |  | | | E.g. Is an Iceberg lettuce an example of "survival of the fittest" or simply 'survival of the crispiest'? | | | | | Ignoring the fact that human intervention is kind of "unnatural" selection, it still follows a normal pattern. Most fruits evolved similarly - because they encourage animals to distribute the plant's seeds, helping with reproduction success.
If you haven't read Dawkins' "Selfish Gene" I'd recommend it, there's a lot on how clear yet subtle the definition of "survival" and "fittest" can be.
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01.11.2020, 09:05
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| | Re: Ask a Scientist | Quote: | |  | | | Ignoring the fact that human intervention is kind of "unnatural" selection, it still follows a normal pattern. Most fruits evolved similarly - because they encourage animals to distribute the plant's seeds, helping with reproduction success.
If you haven't read Dawkins' "Selfish Gene" I'd recommend it, there's a lot on how clear yet subtle the definition of "survival" and "fittest" can be. | | | | | If lettuce doesn't have the seeds and being crispy is a man added quality, though? Is it fittest because we were able to change the dna to our wishes and surviving successfully because we manage to persuade enough kids to eat that bland thing..while other lettuces don't make it.
Is there anything evolutionary in kids disliking certain foods?
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01.11.2020, 09:23
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| | Re: Ask a Scientist | Quote: | |  | | | If lettuce doesn't have the seeds and being crispy is a man added quality, though? Is it fittest because we were able to change the dna to our wishes and surviving successfully because we manage to persuade enough kids to eat that bland thing..while other lettuces don't make it.
Is there anything evolutionary in kids disliking certain foods? | | | | | But lettuce does have seeds, we just don't see them in the shops because by the time they've "gone to seed" it's too late to eat them.
Iceberg is bland, but it has the right crunch for things like sandwiches / burgers. Of the real lettuces that or romaine would be my choice, my other preferences for nussli or rocket aren't actually lettuce.
There probably is something evolutionary in kids preferences, we're evolved to seek calories and lettuce doesn't really work for that. Evolution is a very blunt tool and it will take a while before it catches up with modern food availability.
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01.11.2020, 09:49
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| | Re: Ask a Scientist | Quote: | |  | | | But lettuce does have seeds, we just don't see them in the shops because by the time they've "gone to seed" it's too late to eat them.
Iceberg is bland, but it has the right crunch for things like sandwiches / burgers. Of the real lettuces that or romaine would be my choice, my other preferences for nussli or rocket aren't actually lettuce.
There probably is something evolutionary in kids preferences, we're evolved to seek calories and lettuce doesn't really work for that. Evolution is a very blunt tool and it will take a while before it catches up with modern food availability. | | | | | That would mean adults focus on fiber/nutrients and kids on proteins, which really to my observation is the case. Except some veggies are ok for kids (broccoli, brussel sprouts...others are more gourmands and eat all). I was always intrigued by cravings that copy what we need.
I think Iceberg tastes ok to kids because it isn't bitter but sweet-ish. There is nothing too offensively intense about it.
I can hear my dentist reminding me to eat hard to chew food to stop the evolution of teeth cramming at front part of our mouth.
I am personally not a fan of Iceberg, I like kale, rukola, chard, côte-de-bette..but one doesn't find them so easily in our small community nor sells them easily to kids, either, at dinner times.
__________________ "L'homme ne peut pas remplacer son coeur avec sa tete, ni sa tete avec ses mains." J.H. Pestalozzi “The only difference between a rut and a grave is a matter of depth.” S.P. Cadman "Imagination is more important than knowledge." A. Einstein
Last edited by MusicChick; 01.11.2020 at 10:29.
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01.11.2020, 10:34
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| | Re: Ask a Scientist
I think that with kids, they're often not fond of a food if it doesn't trigger dopamine due to them not liking the taste. So essentially, the pleasure/reward areas of their brains aren't being activated when they eat something that they don't like the taste of.
On a similar note, here is a good article I once came across:
Serotonin & Dopamine: The Neurological Benefits of Chocolate http://web.colby.edu/st297-global18/...-of-chocolate/ | 
03.11.2020, 01:24
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| | Re: Ask a Scientist | Quote: | |  | | | I guess you're referring to quantum electrodynamics / QED as being a mode of transfer for information (electrons absorbing and emitting photons). But in quantum teleportation, information is not exchanged via the interaction of light/photons and matter/electrons in the sense that it is transferred via QED. Teleportation occurs via entanglement, which in turn is now thought to occur via wormholes (Einstein–Rosen bridge).
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The quantum vacuum state does exist, though it does contain fluctuations of energy in the form of 'virtual particles' popping in and out of existence / particle annihilation. But I'm pretty sure the quantum vacuum does not contain hydrogen.  | | | | | ...I wish to see that quantum vacuum...but vacuum as a state doesn't exist...only theoretical in calculations...empty spaces doesn't exist...to believe in teleportation without physical transportation is like to believe in supranatural forces...
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03.11.2020, 10:29
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| | Re: Ask a Scientist | Quote: | |  | | | vacuum as a state doesn't exist...only theoretical in calculations... | | | | | True. The properties a vacuum under field theory are considered to be equivalent to the ground state of the measured problem. So all fields have a basal state (actually the the Higgs field has a non-zero value, at 246 GeV !), including string theory vacuum, featuring non-scalar condensates. | Quote: | |  | | | to believe in teleportation without physical transportation is like to believe in supranatural forces | | | | | You still did not understand my last explanation. Matter is not teleported. It's "information", in the shape of a particle's quantum state. When 2 entangled particles are far appart, information created at one's location is instantly teleported to the entangled particle's location, far appart. That's the only "teleportation" that occurs. It's Einstein's "spooky action at a distance".
And I did understand your previous explanation of particle collision in space. It's just not necessarily correct. Light doesn't propagate through space only by bouncing off hydrogen atoms (it doesn't need to bounce on anything at all, for that matter, it can and does travel through "empty" space just fine). That may very likely be the case in hydrogen rich environments such as interstellar clouds, but unlikely in the geospace. On the geocorona on Earth’s dayside, at 60'000km altitude, there's a hydrogen density of 70 atoms per cm3 (it's denser than on the nightside, as they're compressed by sunlight on the dayside). At the moon's distance there's about 0.2 atoms per cm3. The chances of the photons bouncing off hydrogen atoms are quite low.
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HEAVEN IS A BATHTUB WITH BOOKS THAT DON'T GET WET
Last edited by Caleb; 03.11.2020 at 12:57.
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03.11.2020, 11:27
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| | Re: Ask a Scientist
Could we just agree to ignore Flying Kite's random nonsense?
This used to be an interesting thread | 
03.11.2020, 23:34
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| | Re: Ask a Scientist | Quote: | |  | | | Ignoring the fact that human intervention is kind of "unnatural" selection, it still follows a normal pattern. Most fruits evolved similarly - because they encourage animals to distribute the plant's seeds, helping with reproduction success. | | | | | For me this is the heart of the question (or indeed the lettuce): how is 'unnatural' defined?
In addition to environmental factors, evolution frequently stems from the influence of one species on another (my hummingbird's beak is longer than yours, so there). Taking this view, a successful rose, wheat type, milk cow, dog breed or lettuce is natural evolution.
OR is it only considered "unnatural" if the species propagating the successful genetic change is doing this in 'planned', 'mindful' way? Or maybe it's only unnatural if you mess about with the gene directly in the lab rather than by encouraging a couple of different flowers to smooch? Given that we tend to think humans are the only species special enough to be this consciously manipulative, then pretty much everything we've touched since the first domestication of animals is just a freak show.
Maybe lettuce move to another question...
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03.11.2020, 23:48
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| | Re: Ask a Scientist
Okay, here's a new question.
I had to wait (for a very long time) in the foyer of a building with a glass lift. I had time to notice that, no matter where it went, whether transporting people up or down, once done it always returned to wait on the ground floor.
Perhaps this is usual behaviour for lifts, but I couldn't have know this before, firstly because other lifts I may have (but did not) observe have been closed, and secondly as I've never otherwise (and may I never again!) had such a long time to kill in the presence of a transparent lift. But through the glass I could see that a completely empty lift travelled several floors down, although nobody had summonsed it, to wait at the bottom. Always.
I had previously thought that, in general, lifts waited where someone had last left them, until summonsed by the next hopeful passenger. Was I wrong? Do lifts, even when empty, always settle at ground level? If so, why?
Are they not using electricity unnecessarily, to travel all the way down, for nothing, and then have to travel all the way up again, when someone on a higher storey calls them?
Or does travelling down and waiting on ground level at rest perhaps cost less, in terms of electricity, or perhaps wear-and-tear, as they then don't have to work against gravity, from several storeys up?
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03.11.2020, 23:58
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| | Re: Ask a Scientist | Quote: | |  | | | Okay, here's a new question.
I had to wait (for a very long time) in the foyer of a building with a glass lift. I had time to notice that, no matter where it went, whether transporting people up or down, once done it always returned to wait on the ground floor.
Perhaps this is usual behaviour for lifts, but I couldn't have know this before, firstly because other lifts I may have (but did not) observe have been closed, and secondly as I've never otherwise (and may I never again!) had such a long time to kill in the presence of a transparent lift. But through the glass I could see that a completely empty lift travelled several floors down, although nobody had summonsed it, to wait at the bottom. Always.
I had previously thought that, in general, lifts waited where someone had last left them, until summonsed by the next hopeful passenger. Was I wrong? Do lifts, even when empty, always settle at ground level? If so, why?
Are they not using electricity unnecessarily, to travel all the way down, for nothing, and then have to travel all the way up again, when someone on a higher storey calls them?
Or does travelling down and waiting on ground level at rest perhaps cost less, in terms of electricity, or perhaps wear-and-tear, as they then don't have to work against gravity, from several storeys up? | | | | | Maybe the lift was thinking "I keep coming back down but she still doesn't get in! Why the hell is she still hanging around the damn foyer?"
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03.11.2020, 23:58
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| | Re: Ask a Scientist
Lifts wait at the main entrance floor because that is the most likely floor for them to be needed; far more people go from the entrance to their "home" floor than between floors.
Generally they are balanced with the lift slightly heavier than the counterweight, so going down uses very little energy, but I've only heard of energy capture being used in some show buildings where energy efficiency is the main feature.
Of course if they have to go back up empty, that will waste energy.
If there are multiple lifts, not all will park at the entrance.
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03.11.2020, 23:59
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| | Re: Ask a Scientist | Quote: | |  | | | Maybe the lift was thinking "I keep coming back down but she still doesn't get in! Why the hell is she still hanging around the damn foyer?" | | | | | Thank you, that most unscientific explanation made me chuckle!
The foyer was huge, though, so I was far away from any sensor there might have been, near the lift door.
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04.11.2020, 00:21
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| | Re: Ask a Scientist | Quote: | |  | | | Thank you, that most unscientific explanation made me chuckle!
The foyer was huge, though, so I was far away from any sensor there might have been, near the lift door. | | | | | Glad it made you smile!
On a related note, I've been greatly moved by Schindler's Lifts.....
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04.11.2020, 15:56
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| | Re: Ask a Scientist | Quote: | |  | | | Okay, here's a new question.
I had to wait (for a very long time) in the foyer of a building with a glass lift. I had time to notice that, no matter where it went, whether transporting people up or down, once done it always returned to wait on the ground floor.
Perhaps this is usual behaviour for lifts, but I couldn't have know this before, firstly because other lifts I may have (but did not) observe have been closed, and secondly as I've never otherwise (and may I never again!) had such a long time to kill in the presence of a transparent lift. But through the glass I could see that a completely empty lift travelled several floors down, although nobody had summonsed it, to wait at the bottom. Always.
I had previously thought that, in general, lifts waited where someone had last left them, until summonsed by the next hopeful passenger. Was I wrong? Do lifts, even when empty, always settle at ground level? If so, why?
Are they not using electricity unnecessarily, to travel all the way down, for nothing, and then have to travel all the way up again, when someone on a higher storey calls them?
Or does travelling down and waiting on ground level at rest perhaps cost less, in terms of electricity, or perhaps wear-and-tear, as they then don't have to work against gravity, from several storeys up? | | | | |
I have a friend who is a lift engineer...
It's a programming thing for User Experience. In a tall building almost 100% of people take the lift up, but not 100% ride it down. (Some % walk down the stairs). If the entrance and exit of the building are all on one floor (ground floor), 100% of traffic starts and ends at that level, so statistically if programming to return the lift to its "most likley" next use position, the ground floor makes sense. It also provides incoming visitors with a quicker access to the lift experience for their first impression.
If the lift is fitted with machine learning, it could also work out over time that in the later part of the day the pattern changes, and therefore adapt its parking place accordingly to return to the laziest/busiest floor... (He's not sure anyone has done that bit of programming yet, or even if the logic works).
Kind regards
Ian
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