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posted on Oct, 10 2017 @ 07:59 AM
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First - In reply to some of the critique of various religious and cultural peoples...

The Islamic world while socially can often be pointed at as being rather behind the times, it should be pointed out with a great deal of humility that, Islamic social laws regarding property, women's rights etc people might be surprised to learn where basically far more advanced than our 'western' laws right up until the early parts of the 1900s... All of the great literature of the times...most of it is about how women cant own property and how marriages are all arranged etc etc etc... oh wait! Yes hard to believe that under what is written in the Quran, Yes women do have inheritance, they can own property, they do have rights do devoice. You know... things that are basically not given in the Bible, and which it took to the early 1900s to change in most places in the west... but hey... we are in front now so its time to be critical isnt it? No... its not... not without humility. On Death sentences for certain groups, its abhorrent regardless of which system of law its under, I hope we can all agree on that.

Its mostly about differences in labelling that divides people these days... Example...
In the west, a jilted boyfriend/husband kills girlfriend/wife for leaving him "Crime of passion" or Domestic violence
In the eastern world, its called an Honour killing
We in the west seem to not mind the problem, we don't see it as a stain on our culture or society when men are violent against women... however, when looking at things to poke other cultures/countries/religions for, we jump on Honour Killing like the west never has such things.

Anyway, Islam is an interesting one since, it clearly states in the book that it is a sin not to do what you can with what you have been given, and this passage specifically is directed at intellectualism. IE, education is respected and is a path to lead in your life, and many Muslims, do so quite happily and are not in conflict with their faith at all.

All religions ultimately can be accused of suppressing science when it threatened the establishment, and pointing at one of them only is to be quite ignorant of the truth of what happens and has happened in the past. Id happily point out the kinds of Evil the Christian Religion has brought upon the world, I think the Aids epidemic in Africa can be placed firmly upon their shoulders... but hey... no one worries about that as a stain upon their name do they?


Second - this thread is about pure science, not socio-political science.

DanielKoenig, if you don't like the idea of quantum mechanics in terms of superposition of states, you might want to read into the K-long and K-short particles and the observations of meson oscillation. Something which, classical logic totally fails to explain

edit on 10-10-2017 by ErosA433 because: (no reason given)




posted on Oct, 12 2017 @ 04:24 PM
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originally posted by: ErosA433
if you don't like the idea of quantum mechanics


There are 'things', concepts, events, substance and physical laws, that are a priori eternally impossible in a real natural universe.

A reality can be real, or a reality can be fake (a video game is example of a fake reality, where 'fake physics' can be presented).

A real reality has limited physical possibilities (fake realities do too).

There are things, actions, between substances, that will never be possible in any possible real physical reality.



posted on Oct, 16 2017 @ 11:39 PM
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I watched today's presentation about LIGO/VIRGO and their associates with great enthusiasm, and I have a question. These observations seem to describe the end of light in the universe, is there a description/ongoing story of the emergence of light/light matter in the universe? Thanks again!



posted on Oct, 17 2017 @ 04:01 AM
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a reply to: smokybarnable

In what way do they describe the end of light in the universe? Not sure I understand what it is being asked/stated



posted on Oct, 17 2017 @ 11:58 AM
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originally posted by: ErosA433
Anyway, Islam is an interesting one since, it clearly states in the book that it is a sin not to do what you can with what you have been given, and this passage specifically is directed at intellectualism. IE, education is respected and is a path to lead in your life, and many Muslims, do so quite happily and are not in conflict with their faith at all.
I'm not sure how that's possible. The time travelers in the cave mentioned in the posted patent as stated by the Islamic holy book is not feasible by any known science, so the claim that science can show how this happened is false. So a scientist would have a few options, such as to believe that maybe it is just a story and never happened which is a conflict with Islam, or maybe that there is as yet some unknown science that could explain it which I tried to examine in my post and showed how extremely unlikely that scenario appears, or maybe it was some kind of magic or deity intervention which of course science can't rule out but this is not a scientific world view. This leads to the first option being the most scientific and the possible death penalty for Apostasy if that is followed to the ultimate conclusion. So sure following an intellectual path is great advice until it may lead to your death for doing so.


All religions ultimately can be accused of suppressing science when it threatened the establishment, and pointing at one of them only is to be quite ignorant of the truth of what happens and has happened in the past. Id happily point out the kinds of Evil the Christian Religion has brought upon the world, I think the Aids epidemic in Africa can be placed firmly upon their shoulders... but hey... no one worries about that as a stain upon their name do they?
In the context of the post in this thread regarding the time travelers in the Koran, well if some other religion had been cited I would have attacked that pseudoscience as well, however the Catholic church has made some progress in the last 300 years. They finally apologized to Galileo over 300 years after they threatened to turture him for promoting his heliocentric view, and they no longer threaten to torture or kill people who decide they don't want to follow their religion any more, which in my view may include scientists in particular who are most likely to see the disconnect between religion and science.


Second - this thread is about pure science, not socio-political science.

Given your "All religions ultimately can be accused of suppressing science", I'm not sure if that's true of all religions (is Buddhism a religion and did it suppress science?) but it's certainly true of some and the most problematic in my view are the young earth creationists. They try to market their brand of pseudoscience as "creation science" when it's not science at all, it's a religious belief masqueraded as science and worst of all they've tried to introduce this into classrooms. This thread and other online resources may be as close to a classroom as some adults who have long left school are likely to get, so I don't think it's so easy to separate when our goal is to keep science in the classrooms and keep pseudoscience out.

edit on 20171017 by Arbitrageur because: clarification



posted on Oct, 17 2017 @ 12:01 PM
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originally posted by: smokybarnable
I watched today's presentation about LIGO/VIRGO and their associates with great enthusiasm, and I have a question. These observations seem to describe the end of light in the universe, is there a description/ongoing story of the emergence of light/light matter in the universe? Thanks again!
I didn't see that presentation, but here's my understanding of evolution of light in the universe.

The big bang resulted in mostly hydrogen, and some helium, and traces of other elements. Mostly hydrogen is key because when clouds of hydrogen gravitationally collapse into large enough objects, stars can form which give off visible light. Jupiter would need to have maybe 80 times more mass than it does for this process, so it gives off some thermal radiation as do all objects above absolute zero but no light from fusion like the sun.

Once the star has fused all the hydrogen it can, it may proceed to fuse heavier elements if it has enough mass, but eventually it fuses everything it can and runs out of fuel for fusion. Smaller stars leave a core behind and larger ones explode in novae.

More clouds of hydrogen can collapse into stars and they may include some remnants of the novae like our sun does.

This can go on for a number of cycles as long as there is hydrogen available to collapse and form stars, but there's only a finite amount of hydrogen (and other fuels that stars can fuse) in the observable universe, so, once all that fuel is consumed, there won't be as much light in the universe.

There was a brief transient light event associated with a LIGO/VIRGO event believed to be a kilonova which gives off enormous amounts of gamma rays (electromagnetic radiation beyond visible frequencies), followed by a short burst of EM radiation in other frequencies including visible light. So there can be short flashes of light as neutron stars merge, but it's transient. Eventually all that will be left might be black holes and neutron stars and the brief flashes that happen as they merge, though I can't say we're certain about that, it just seems most likely based on what is known at this point.

People have hypothesized that there could be mechanisms to generate more hydrogen that we don't currently understand, and if that's so it could fuel more stars. That idea is mentioned in this wiki article:

Heat death of the universe

If the cosmological constant is zero, the universe will approach absolute zero temperature over a very long timescale. However, if the cosmological constant is positive, as appears to be the case in recent observations, the temperature will asymptote to a non-zero, positive value and the universe will approach a state of maximum entropy.[8]

The "heat death" situation could be avoided if there is a method or mechanism to regenerate hydrogen atoms from radiation, dark energy or other sources in order to avoid a gradual running down of the universe due to the conversion of matter into energy and heavier elements in stellar processes.
That last sentence is the bottom line for me. The universe converts matter into energy and heavier and heavier elements which ultimately are too heavy to support stellar fusion, which leads to the idea that eventually there won't be much light. Whether some other process will create new sources of hydrogen or not I can't say. If someone knows of such processes I'd like to hear about them which I think is ultimately related to your question, because more hydrogen is basically what stars would need to keep making light after all the available hydrogen is used up (combined into heavier elements via fusion).


edit on 20171017 by Arbitrageur because: clarification



posted on Oct, 17 2017 @ 01:26 PM
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a reply to: Arbitrageur

Righto! OK following from this reply I kinda understand the question, and another great post by Arb.

It should be pointed out for completeness (though isn't to say Arbitrageur is incorrect in any way) for a more detailed picture, is the following.

The life cycle of stars does vary by mass, though when a star reaches the end of its life, it has only burnt the hydrogen available to the core of the star. You may think "Hot things rise and so, cool hydrogen should fall and hot helium should rise" but in most cases, the conditions required for convection are not met at the core of stars and such minimal mixing and refreshing occurs beyond diffusion.

It is only the coolest M stars (if memory serves) which are believed to have a fully convective core, these are also some of the least interesting objects in terms of stellar evolution... since they just kinda... sit and burn away before fizzling out after 10 billion years. No bang, no excitement... just meh

What this appears to point at, is that we now have a new source of nuclear processes that can change the material composition of the general universe. It allows another check and balance. It also could be where some of the discrepancies are.



posted on Oct, 17 2017 @ 04:31 PM
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Thanks to Arbitrageur and ErosA433 for the great answers, plenty to think about!



posted on Oct, 17 2017 @ 04:35 PM
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Could quantum computers be used for instant communications via entanglement, and if so, could that be why we haven't intercepted otherworldly communications? I know little about physics so if this question is not appropriate for the thread, my apologies.



posted on Oct, 17 2017 @ 04:49 PM
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originally posted by: Autorico
Could quantum computers be used for instant communications via entanglement


no



posted on Oct, 17 2017 @ 09:29 PM
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a reply to: Arbitrageur

When I read the post by Smokeybarnable, I thought he/she was referring to light i.e. our visible light 400-600 nm. I'm probably wrong, but that's how I interpreted it.

Anyway, I was thinking about the photon which is what we call light. My question is about the photon's interaction with an electron. A photon can be absorbed by an electron which is then moved to a higher orbital. When the electron moves to a lower orbital, it emits a photon. So why do you need hydrogen? The photon-electron circuit almost sounds like a perpetual motion machine. Imagine that one electron and one photon could be isolated. If the electron absorbs the photon it gains the photon's energy. When the electron emits the photon it loses the energy which is gained by the photon. What would prevent that system from being infinite? This is probably 100% wrong, but just a thought.



posted on Oct, 18 2017 @ 08:50 AM
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a reply to: Phantom423

You wont get any orbitals with a lonely electron.



posted on Oct, 18 2017 @ 10:37 AM
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originally posted by: moebius
a reply to: Phantom423

You wont get any orbitals with a lonely electron.


How about this setup - add a couple of photons - see what happens when they're absorbed by the electron and emitted at a lower orbital - could it be done?



physics.aps.org...




Until recently, experimenters could directly probe isolated electrons in only their ground state and first excited state without destroying the system during the measurement. But in the 16 August PRL a pair of Harvard researchers shows how to trap a single electron in a magnetic field and coax it into four different excited energy levels. This “quantum cyclotron”–an example of an “artificial atom”–could lead to a closer investigation of basic quantum mechanics and to extremely precise measurements of some fundamental constants of nature.





They observed transitions between energy levels by measuring changes in the natural frequency of the axial motion, so they deduced the circular orbital motion without directly disturbing it. The team cleanly observed staircase-like changes in energy levels as each photon was absorbed or emitted, and they could even measure the electron’s temperature by counting the number of transitions into excited states.



posted on Oct, 18 2017 @ 12:19 PM
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a reply to: Phantom423
I think what is going on here is that the electron is trapped by a magnetic field, and it moves in a spiral like manner in a circle. This is essentially a potential well with an electron inside.

So the orbitals of an atom are formed because of an electrostatic well.

The system works because the electron can absorb the energy and it will then move to a higher energy in the well. For a electron in a cyclotron, this would basically mean the frequency and spacial dimension of its spiral path would change.

*I think*



posted on Oct, 18 2017 @ 12:45 PM
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a reply to: ErosA433




The system works because the electron can absorb the energy and it will then move to a higher energy in the well. For a electron in a cyclotron, this would basically mean the frequency and spacial dimension of its spiral path would change.


Would the electron interact with a photon in a magnetic field? The photon doesn't have a charge, but wouldn't a photon exert an electrical or magnetic force on a charged particle? If that's the case, then as a photon approaches and electron, even in a magnetic field, wouldn't the electron absorb and emit the photon? The electron acts as a wave and the photon as a particle - the wave/particle duality. Does that change in a magnetic field? Thanks for the reply.



posted on Oct, 18 2017 @ 09:15 PM
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Knowing nothing, have magnetic fields been shown to create photons from electrons, for instance? Do magnets produce fundamental particles?



posted on Oct, 19 2017 @ 04:01 AM
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a reply to: Phantom423

Not sure I can answer all those in a satisfactory manner but;
Would the electron interact with a photon in a magnetic field - Yes, the electron, by virtue of being electrostatically charged means that it has a coupling to the electro-magnetic field. It is already interacting with the magnetic field, since it is moving and has its motion changed in the cyclotron. A photon, being an electromagnetic particle inherently can interact with the electron. The wavelength of the photon here defines the energy it has by

E=hc/lambda

So if the electron absorbs the photon, it will basically obtain that photons energy. The form of this would be a change in momentum, which would cause the electron to change its 'orbital' configuration or Energy level in the cyclotron.


The Electron is free to re-emmit a photon, though the properties of which will depend upon the magnetic field. Thus once the electron is in this different state, the magnetic field could be altered (for example) which could change the amount of energy the electron could 'drop' or loose if it was to emit a photon.

The electron and photon act as both depending upon what component of the experiment you look at. Pure interaction level, it is acting as particles, the wave nature is an expression of the energy pretty much. If geometrically, then the photon is an excitation of the EM field, its wave-nature is its energy as i said above and the particle-nature is its confinement to a point in space. The electron's wave nature is its orbital configuration as it makes a spiral around the cyclotron

Not sure if that is any good but its my thoughts on it.



posted on Oct, 19 2017 @ 12:01 PM
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originally posted by: Phantom423
a reply to: Arbitrageur

When I read the post by Smokeybarnable, I thought he/she was referring to light i.e. our visible light 400-600 nm. I'm probably wrong, but that's how I interpreted it.
That was my interpretation too. I only mentioned EM radiation in other frequencies like the thermal IR emissions from Jupiter to contrast that with visible light from the sun resulting from fusion.


Anyway, I was thinking about the photon which is what we call light. My question is about the photon's interaction with an electron. A photon can be absorbed by an electron which is then moved to a higher orbital. When the electron moves to a lower orbital, it emits a photon. So why do you need hydrogen? The photon-electron circuit almost sounds like a perpetual motion machine. Imagine that one electron and one photon could be isolated. If the electron absorbs the photon it gains the photon's energy. When the electron emits the photon it loses the energy which is gained by the photon. What would prevent that system from being infinite? This is probably 100% wrong, but just a thought.
What you describe does happen except for the infinite part, it's more or less how energy works its way from the core of a star like our sun where fusion takes place, to the outer surface where the photons are finally emitted at the speed of light. If a photon could travel from the center of our sun to the outside "edge" at the speed of light, it would only take 2.3 seconds to get there, but similar to your suggestion it can't do that but only travels a short distance before it's absorbed by another atom, them re-emitted, and so on, so because of that "pinball-machine" like action of excitation moving from atom to atom, some estimates say it takes many thousands of years for the energy in the sun's core to work its way to the surface that way.

But once the photons leave the sun at the speed of light, let's look at those which hit the earth. You probably know our climate models are extremely complex and even so probably still inadequate for an accurate description but some of the radiation the earth receives from the sun as visible light is re-emitted as thermal radiation, not as visible light, so hopefully this makes it obvious why the process is not infinite for visible light. See the red arrows representing thermal radiation leaving the Earth on the right in this schematic:

What Is the Greenhouse Effect?



originally posted by: Phantom423
How about this setup - add a couple of photons - see what happens when they're absorbed by the electron and emitted at a lower orbital - could it be done?
physics.aps.org...
It's kind of hard to follow your train of thought (if there is one) here, but if this is some kind of follow-up to your previous question, I presumed you were talking about naturally occurring processes, which was the inferred context of smokybarnable's question you referred to, but the follow-up question about an electron being excited in a magnetic field is a laboratory experiment. While we can often make inferences about naturally occurring processes as a result of lab experiments, they don't always precisely duplicate what happens in nature outside the lab.



posted on Oct, 19 2017 @ 03:03 PM
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@ErosA433 @Arbitrageur

Thank you both for your detailed replies. I didn't communicate my thought experiment very well. Here's what I meant:

Smokybarnable asked if there could be an end to light in the universe. Arbitrageur replied that if there was enough fuel, the process of producing light would continue.

My question was just a thought experiment: Forget the universe for a minute. If you isolate an electron and a photon, is it possible for that adiabatic system to produce light infinitely? (The cyclotron post I made was in response to Moebius' comment that isolating a single electron probably wasn't possible. Apparently, there are several ways to isolate electrons now.)

Moving along to my question:

Below are two Feynman diagrams - one for absorption and one for emission. Imagine a single layer of electrons in a closed system. I understand that it would produce a magnetic field, have angular momentum and carry a charge. The system has no photons and the electrons are in their ground state. Nothing enters and nothing leaves. Now introduce photons into the system. As the electrons absorb the photons the electrons move to a higher orbital. When the electrons move back to their ground state, they emit a photon - which is light. Any electron would behave this way - wouldn't have to be from hydrogen.

The root of the question: Is it hypothetically possible for the system as described to be an infinite perpetual motion machine. It's simply photon in/photon out - electron in ground state/electron in higher orbital. Would the system continually produce light?




edit on 19-10-2017 by Phantom423 because: (no reason given)

edit on 19-10-2017 by Phantom423 because: (no reason given)



posted on Oct, 19 2017 @ 05:15 PM
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originally posted by: Phantom423


The root of the question: Is it hypothetically possible for the system as described to be an infinite perpetual motion machine. It's simply photon in/photon out - electron in ground state/electron in higher orbital. Would the system continually produce light?






No. First why wouldn't the photon just add momentum to the electron?
But second, an isolated electron can't emit a photon.

For proof You're going to have to use E2 = p2 c2 + m2 c4

Initial electron = mc2. Final state of electron after photon absorption will have momentum p. So if you also have a photon emitted in order for energy to be conserved the photon could only have had negative energy.




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