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  4. Do atoms exist in multiple places at once, 2 places or 1?
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Do atoms exist in multiple places at once, 2 places or 1?

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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #20 on: 10/07/2021 19:34:56 »
Quote from: Halc on 10/07/2021 00:48:18
Ouch. So ignore science then and hold whatever beliefs are required for you to keep your marbles together. That seems to be one of the primary benefits of being religious: to hold beliefs that one finds comforting rather than ones based on evidence.

I detest the idea of people adopting whatever belief they want, especially if they're only doing it because they find reality unmanageable. If someone I knew became a flat-earther and it brought them comfort, I would tear that away from them without a moment's hesitation. No belief should be acceptable if it's a lie, no matter how beneficial it is. It's why I don't like the DaVinci Code, Wicked or the musical The Book of Mormon.
« Last Edit: 10/07/2021 19:38:45 by Multifaceted »
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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #21 on: 10/07/2021 20:23:17 »
To clear things up,
I thought atoms might exist in infinite positions at once.

Then Eternal Student said some things that suggested they weren't.

I quoted him and asked some new questions expecting him/her to respond.

Halc responded instead.

Then I posted a list of examples Halc had asked for earlier. I specifically said they were just examples of how people I'd talked to were so absolute in their opinions and I diddn't want to discuss them here. But people did anyway.

Then Halc and alancalverd said some thing that supported one of the theories I had listed and since this one is such a huge concern for me I wanted them to tell me if they really thought it was true.

So I asked Eternal Student to answer if atoms are like compacted marbles and Halc and alancalverd to answer if matter is finitely arrangeable or not.

In the past I have found little compassion, been strung along and even called mentally ill by people on forums like this. And now I'm afraid that's the reputation I'll have here too.
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Offline Eternal Student

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #22 on: 10/07/2021 23:05:46 »
Hi again.

Quote from: Multifaceted on 09/07/2021 22:11:35
Also, I am still waiting for Eternal Student to reply to when I quoted him about atoms.
   Sorry.  I've been stuck on something else.   I'm rushing this reply out now.

Quote from: Multifaceted on 08/07/2021 03:40:20
Actually that was going to be my next question. If atoms aren't in many places at once, does that mean they're like the grains in a sand castle or uniform marbles?
   In some models but none of them are perfect representations of reality.  For example, when two atoms are in close proximity they feel electromagnetic forces from each other.  This deforms them (changes their shape).  If we use Quantum Mechanics as our model then we would say that the first atom experiences a different potential when it's close to the other atom and so it's electron orbitals will be slightly different.     In effect then if we pack a hundred atoms closely together like the steel marbles you showed in your diagram, then each marble could still be unique.  The ones near the surface become a different shape to the marbles right at the centre of the structure.
   So the atoms are more like the grains of sand in your castle rather than uniform marbles,  examine each one carefully and it is not the same as the grain of sand next to it.   This all depends on the model you're using and doesn't seem to be your main concern.

Quote from: Multifaceted on 08/07/2021 03:40:20
To me a wave is something that you find at the beach, it's not exactly a thing, its a disturbance that dissipates back into the water. I know about how light has a wave length but I don't understand how anything solid can be made out of it.
     Well, that's you and me both then.  As human beings we have a notion of what a solid thing is and waves don't seem to be solid things.  However, we have to examine carefully what a solid thing might really be instead of just what we think it is.  Let's take a simple idea and define a solid thing as something we can't push our finger into.  Now what is stopping us pushing our finger into the table?  If we look at a microscopic scale then particles in our finger never come into direct contact with particles in the table.  There are negatively charged electrons around the atoms in the table and around the atoms in your finger.  When you get them close to each other there is huge electrostatic force pushing them apart.  That force is what prevents you being able to push your finger into the table.   
   So our understanding of what is solid might include an electromagnetic wave that repels your finger....

Ok, that was rushed.   There is no way we can discuss atomic theory or quantum mechanics in 10 minutes.

- - - - - - -
   Your main concern seems to be about the true nature of things.
1.  Please remember that science doesn't offer absolute truth.  Only some models that are useful and often allow predictions to be made.

2.  Almost all experts in any area get depressed.    I'll find some famous Physicist's quotes if you like.    There are many theories that can be quite worrying.    However, the same is true in most fields of study.    Van Gogh was an artist who became quite troubled.      Philosophy forces people to ask questions like  "do you have free will".     History often forces people to ask if we repeat things.
     There are also many fantastic and cheerful ideas in science.   For example, it is amazing that human beings have evolved and we are here.

I'll write more later and I need to read over this whole thread again to see what's happened.  I have to go and be a taxi service for one of my children in a few minutes.
Bye for now and best wishes.

(Late editing to reduce the number of spelling mistakes).
« Last Edit: 11/07/2021 00:19:48 by Eternal Student »
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #23 on: 11/07/2021 00:52:35 »
Quote from:
this theory about matter and I find that upsetting.
A theory about the wave nature of matter has been upsetting physicists for a century.
- And the same discussion about the nature of light was upsetting physicists for centuries before that (back to Newton and beyond).
- But it has no impact on daily life - 99% of the world's population goes about their daily life without knowing that it is even a question. It just doesn't affect anyone's daily life in any way that you could detect
...unless you are a physics teacher without a $1 million budget, trying to dream up ways to demonstrate these subtle effects to physics students, .

You indicate that you are an artist (not a physics teacher), and yet this theory does appear to be affecting your daily life.
- So I would suggest talking to counselor, to get things in some perspective

Quote
I HATE the Hitchhikers Guide to the Galaxy
It is a parody - demolishing one house is equated to demolishing a whole planet...

It is important for us to be able to laugh at ourselves sometimes - it helps to put things in perspective...
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Offline Eternal Student

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #24 on: 11/07/2021 04:38:10 »
Hi again.

Quote from: Multifaceted on 10/07/2021 20:23:17
Then Eternal Student said some things that suggested they weren't.
I quoted him and asked some new questions expecting him/her to respond.
Halc responded instead.
  1.  I haven't seen much need to disagree with Halc or any of the others who have replied here.
  2.  You seem to be giving my opinion more importance than it deserves.  I know Halc has made comments about being just "some random guy on a forum" but that's just him being polite and very modest.  Most of the people who have replied here are "the moderators" - they run and manage this forum and they are the experts in one or more fields of science.  I am a better example of  "a random guy on a forum".

One of the problems of replying is that earlier replies get pushed further down and some important information in them can be missed because people often only read the newest replies.  Evan_au mentioned something that shouldn't be buried under my reply:
   
Quote from: evan_au on 11/07/2021 00:52:35
this theory does appear to be affecting your daily life.
- So I would suggest talking to counselor, to get things in some perspective
    That's good advice for everyone.  Your (everyone's) health is a high priority.
    You (Multifaceted) have already made comments stating that you didn't want to give too many details of past discussions.  This is perfectly sensible.  A public forum like this one is not a safe place to disclose personal information anyway.  We're going to discuss science here because that is all we can do.

Quote from: Multifaceted on 10/07/2021 19:34:56
No belief should be acceptable if it's a lie, no matter how beneficial it is.
   Then I will start with an apology.  There are things that I think are true but I may be wrong. 
Science teachers present simple scientific models and ideas to their students.  Sometimes the students think that these are all true but they aren't.  The models are useful and seem to work well in most situations.  It is the best we (human beings) can offer.

Quote from: Multifaceted on 08/07/2021 03:40:20
So are you saying no one knows what atoms are like?
   I'll support Halc's answer here:    I think that's a reasonable statement
However, there are about seven and half billion people in the world.  I haven't asked them all.
It's fair to say that Science has many different models of an atom.  There's one called the "plum pudding" model which is quite old and fails to explain most things so it's not popular anymore.  There's a model that is usually attributed to the scientists Rutherford and Bohr which is better in that it explains more things.  The Rutherford-Bohr model is the one most people will learn about in school.  There are more complicated models than this which are usually studied in University.  Many of the replies in this thread are trying to cover the gap between the school model and the University model (where Quantum Mechanics is used to build a model of an atom).  All of the models are still useful in some situations.  Quantum Mechanics may be more accurate but it's much more complicated and sometimes we just need a simple model and rough answer.
 - - - - - - -
Quote from: Multifaceted on 10/07/2021 20:23:17
To clear things up,
I thought atoms might exist in infinite positions at once.

 .....Then I had a load of responses about various related and partially related topics......
    Well, this is a good thing.  This is a forum, a place for discussion and some exposure to new ideas.  If you're really lucky you might identify some new questions that are worth asking.   It'll be a sad day when (or if) science has all the answers because there will be nothing left to discover.
    I know that sometimes it can get a bit confusing, especially if all you want is a straight answer but sometimes there isn't a straight answer that can be given.

Bye for now and best wishes to you.
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Offline Colin2B

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #25 on: 11/07/2021 09:04:26 »
Quote from: Multifaceted on 10/07/2021 20:23:17
In the past I have found little compassion, been strung along and even called mentally ill by people on forums like this. And now I'm afraid that's the reputation I'll have here too.
The only way people on forums such as this can form opinions about you is through what you type on your keyboard. So those opinions are very much under your control. If you keep your comments here to science questions you should have no problems.

It is worth mentioning that we get a lot of people here who are frightened by many scientific theories and sometimes become very angry, trying to deny relativity, quantum mechanics, evolution etc. It is also worth understanding that in science we have a very different meaning to theory than that used by the general public. To us a theory is a way of describing the way the universe around, us and the objects it contains, behave and for which there is a great deal of solid experimental and observational evidence to confirm the theory. To me these theories are not frightening, they are an opportunity to understand why things are the way they are; it is a real journey of discovery.

Some of these theories can run counter to what our senses or ‘common sense’ tell us are true. It took a long time for people to realise that the earth goes around the sun despite what our common sense tells us, which only goes to show how common sense can be fooled. This is also a good example of how, as more information becomes available, scientific theories are refined and updated.

It has also been mentioned that the popular press often misrepresents scientific theories in order to make them more exciting, this is particularly true in the area of electrons, atoms and quantum mechanics.

You have had a lot of good answers to your questions and probably need time to absorb the new information, but do continue take the opportunity to ask questions and increase your understanding of the world around us. Enjoy.
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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #26 on: 13/07/2021 21:10:57 »
Quote from: Eternal Student on 10/07/2021 23:05:46
If we use Quantum Mechanics as our model then we would say that the first atom experiences a different potential when it's close to the other atom and so it's electron orbitals will be slightly different.     In effect then if we pack a hundred atoms closely together like the steel marbles you showed in your diagram, then each marble could still be unique.  The ones near the surface become a different shape to the marbles right at the centre of the structure.
   So the atoms are more like the grains of sand in your castle rather than uniform marbles,  examine each one carefully and it is not the same as the grain of sand next to it.   This all depends on the model you're using and doesn't seem to be your main concern.

But if atoms are like that then there must come a point when you pack them in close as the can and they can't get any closer. Resulting in finite possibilities.

Quote from: Eternal Student on 10/07/2021 23:05:46
1.  Please remember that science doesn't offer absolute truth.  Only some models that are useful and often allow predictions to be made.


Really? I thought science was exactly about absolute truths. At some point I assumed that out there there is some kind of international council of scientists who deem what goes into books about science. What is officially true or false.

So when people say atoms exist in multiple places at once what they really mean is we can't find an atom until we look for it?

I used to know someone who has a physicist for a friend, she asked him about this matter-finite-arrangement theory and he said.

"We now accept that we cannot measure or predict the position or arrangement of any quantity with regards to particles and how they arrange themselves in the universe.

There are lots of attempts to bring order to this but all involve the understanding that there are an infinite number of arrangements of any space and that these only arrange themselves when we look at them. Therefore, there can be no limit to creativity only to our imagination of what is possible."

But if superpositions are just not knowing where the atom is, doesn't that void this statement?

Also it seems that the people here do not fully appreciate how much this theory has hurt me or why. My first reaction was to elaborate further but then I remembered that this may not be the proper place for it.
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #27 on: 13/07/2021 23:53:22 »
Quote from: Multifaceted
But if atoms are like that then there must come a point when you pack them in close as the can and they can't get any closer. Resulting in finite possibilities.
At room temperature, gold atoms are packed about as close as you can get them.
- But it turns out that if you manufacture them as gold nanoparticles, they can produce a lot of different colours (quite different from the traditional jewelry colour)
- It turns out that some makers of stained glass windows used gold nanoparticles to produce various colours in their creations
- So the finite arrangements of gold atoms did not inhibit the creativity of these craftsmen at all
- As I heard this morning, gold nanoparticles are used in pregnancy tests and rapid COVID tests - so the finite arrangements of gold atoms did not inhibit the creativity of the scientists who developed these tests, either.
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Offline Eternal Student

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #28 on: 14/07/2021 00:47:46 »
Hi again.

Quote from: Multifaceted on 13/07/2021 21:10:57
But if atoms are like that then there must come a point when you pack them in close as the can and they can't get any closer. Resulting in finite possibilities.
    Atoms resist being packed together too closely.  If we are going to force the atoms to pack together closely then we have to include that force as part of the overall thing we are considering.  You are an artist, so this is like saying we cannot consider a painting just as some different bits of paint in some order.  We have to include the canvass which holds all the paint in that place.  If you take the canvass away, the paint won't stay in the right places.
   The obvious example of a force that can pack atoms together as much as possible is gravity.   Neutron stars are thought to be the most dense matter in the universe.  In a Neutron star the atoms are packed together so closely that we imagine the nucleus of the atoms are in contact.  I should make it clear that this a very rough model of a Neutron star.  No one has been to a Neutron star and no one could survive there.   Certainly we haven't sampled and "looked" at the stuff a Neutron star is made of.
     Anyway, there are two points of interest about Neutron stars:

1.   If we could sample the material a Neutron star was made of and we took it away from it's original environment then it won't look or behave like Neutron star material anymore.  We believe the atoms would quickly re-capture electrons and move apart to return to something more like ordinary atoms in ordinary matter.    Similarly, even if two artists just happened to create the same painting, they won't look the same unless they are in exactly the same place and under the same lighting.  Due to tonal differences perceived by the observers, the two paintings will not elicit exactly the same emotional response in the observers.  Regarding the art as a dynamic exchange or phenomena between artist and audience, then the two pieces of art are different just as a result of being in different places.

2.  Sometimes gravitational forces can be so strong that even though we were reasonably certain the atoms should not and could not get any closer,  somehow and in some way.... something remarkable happens.  The Neutron star is changed into something completely different, something that isn't like matter anymore - It becomes a Black Hole.  This is a wonderfull thing for a Physicist and we would very much like to know what it is.   However, it is like a poem that has been sealed inside a clay model by an artist.  We can see the outer surface of the clay model and it's fascinating but we can't see the message that the artist had sealed away on the inside.  It could be a whole other universe in there.
- - - - - -
Quote from: Multifaceted on 13/07/2021 21:10:57
Really? I thought science was exactly about absolute truths. At some point I assumed that out there there is some kind of international council of scientists who deem what goes into books about science. What is officially true or false.
    There isn't an international council that I know of.  However, there are procedures through which science maintains some standards.  I'm mainly thinking about "peer review".  New theories and new discoveries will tend to published in some recognised journals.   The articles or "papers" submitted to those journals are reviewed by established, already recognised experts before publication.   
   Even after publication in some journal, the review process is effectively ongoing by the experts working in that field who will end up reading that article.  If a University lecturer doesn't find the article sensible they won't tend to use it in their lectures and so they won't pass on that information.  If other experts feel strongly that the article was wrong in some way, then someone will publish an article with a counter-argument or experimental proof against the original article.
    If someone had new ideas or new information about some piece of art history - how would they get this information published and recognised by the other experts in art history?  Scientific peer review is much the same as that, I would have thought  (but I haven't studied much Art history and I really wouldn't know).

Quote from: Multifaceted on 13/07/2021 21:10:57
So when people say atoms exist in multiple places at once what they really mean is we can't find an atom until we look for it?
     Maybe.   Your understanding of this principle in quantum mechanics links to another statement you made later:
 
Quote from: Multifaceted on 13/07/2021 21:10:57
But if superpositions are just not knowing where the atom is, doesn't that void this statement?
   We tend to say the particle was in a superposition of states until it is measured.  This is different from assuming the particle was always in the place where we found it but we just didn't know it was there.  Until the particle was observed it didn't HAVE to be anywhere,  a precise location wasn't a property that the particle had to have.   Let's try to re-phrase and re-explain this:
     In a simple quantum mechanical model of a particle that exists inside some environment (physicists will want to say "potential" instead of "environment")  then the particle does have a property associated with it.   That property is called it's wave function.   That's all there is for the particle, the wave function tells us everything about the particle.
     There isn't a separate property that is the location of the particle.  If that information (the location of the particle) exists then it is held or encoded within the wave function.  We can try to get that information out of the wave function.  If we are successful, then that information exists and the particle must have a definite position.   However, sometimes we can't get that information out of the wave function and then the particle doesn't have to have a definite location at all.  If we force an observation on the particle's location then we force the wave function to change.  The new wave function does encode the location of the particle and so it does have a definite location.     NOTE:  This is based on what is called the Copenhagen interpretation of Quantum Mechanics.   There are alternative interpretations.  This is another example where Physics isn't offering the truth just a model that is useful.
- - - - - - -
TIME is another wonderful thing in physics.  It seems to flow only one way and makes everything dynamic and performable only once.   Even if there was another artist like yourself somewhere else,  they cannot produce the same work of art here and today.  Only you were here today and there is no way that the other artists can wind the time clock backwards and repeat that.

Bye for now and best wishes to you.
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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #29 on: 14/07/2021 18:39:43 »
Quote from: Eternal Student on 14/07/2021 00:47:46
You are an artist, so this is like saying we cannot consider a painting just as some different bits of paint in some order.  We have to include the canvass which holds all the paint in that place.  If you take the canvass away, the paint won't stay in the right places.

Quote from: Eternal Student on 14/07/2021 00:47:46
Similarly, even if two artists just happened to create the same painting, they won't look the same unless they are in exactly the same place and under the same lighting.  Due to tonal differences perceived by the observers, the two paintings will not elicit exactly the same emotional response in the observers.  Regarding the art as a dynamic exchange or phenomena between artist and audience, then the two pieces of art are different just as a result of being in different places

Quote from: Eternal Student on 14/07/2021 00:47:46
TIME is another wonderful thing in physics.  It seems to flow only one way and makes everything dynamic and performable only once.   Even if there was another artist like yourself somewhere else,  they cannot produce the same work of art here and today.  Only you were here today and there is no way that the other artists can wind the time clock backwards and repeat that.

I've heard similar augments before and they diddn't convince me that the theory wasn't true. If anything, statements like this only make it seem more true. But thank you for the rest of it.

Quote from: Eternal Student on 14/07/2021 00:47:46
We tend to say the particle was in a superposition of states until it is measured.  This is different from assuming the particle was always in the place where we found it but we just didn't know it was there.  Until the particle was observed it didn't HAVE to be anywhere,  a precise location wasn't a property that the particle had to have.

Are you saying the act of measuring it is what places it there? That it's no place until we do that?
But like the old saying goes, everything's got to be somewhere.
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Offline Eternal Student

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #30 on: 15/07/2021 00:26:09 »
Hi again.

   Well it looks like you've done well getting over the usual crisis and concern that is intrinsic to art.  Art still worries me a lot.

   I went to the Tate Modern as a student and we (a few friends who dragged me along) saw a pile of stones arranged on the floor in one of the art installations.  I was actually quite impressed with the pile of stones but something about it troubled me greatly.   :-\
   My concern was that there might be a work of art in the garden of my flat and I might accidentally destroy it by moving some of the stones around.  I did this often when I needed something heavy to keep the lid on my dustbin.  As an artist you might be able to grasp the catastrophic loss if, by chance, there was the greatest work of art in my garden and the whole world lost it just because I was worried about my dustbin lid coming off in high winds.
    Anyway, I now have dustbin lids that you can push down and twist to lock them in place but that's not the main point.  The main thing is that my artist friends said the following:
    Even if, by chance, there was a pile of stones in your garden that was exactly the same as the arrangement we saw in the Tate Modern,  it still wouldn't be art.  To be art there has to be an idea involved and expressed.  Since no artist put the stones in that place, there was no such idea and it wasn't art.

    Art has got nothing to do with a particular arrangement of things (like atoms) that fall into a particular arrangement by random chance.  It's about ideas and a dynamic exchange between artist and audience.   Stop worrying too much about one theory in science, keep everything in sensible proportion and this concern might just give your art a bit more of an edge or uniqueness about it.
   
Quote from: Multifaceted on 14/07/2021 18:39:43
Are you saying the act of measuring it is what places it there? That it's no place until we do that?
    Something like this is one reasonable interpretation of Quantum Mechanics.  Measurement can be the cause of change in the wave function.   There are other interpretations.
Quote from: Multifaceted on 14/07/2021 18:39:43
But like the old saying goes, everything's got to be somewhere.
   Old sayings and common sense are often quite good for human beings.  They allow us to find food and shelter and react to events in a way that will tend to keep us alive.  They are useful models but not necessarily the most accurate models.  When we're considering very small particles, smaller than you can see with the naked eye, these simple models and old sayings don't seem to hold very well anymore.

Best wishes to you.
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #31 on: 15/07/2021 00:48:36 »
Quote from:
Are you saying the act of measuring it is what places it there? That it's no place until we do that?
Another interpretation of quantum theory says that until we measure it, it is everywhere.
- A weaker form is "it could be anywhere"

But in all interpretations of quantum theory, it is more likely to be in some places than in other places (that is defined by the amplitude of the wave function).
- And if you are talking about a gold atom in a solid block of gold, it is most likely to remain fairly close to its original position
- Unless you, as the artist, are working the gold into a piece of jewelry
- Gold is quite malleable, so the layers of atoms slide over each other fairly easily; in such a dynamic environment, the "original position" is not so easy to define!

The various interpretations of quantum theory have no day-to-day impact on Physicists, let alone on non-physicists like yourself.

Don't let it bother you!
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Offline Zer0

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #32 on: 16/07/2021 23:27:48 »
I wonder how do they even get to a Total Vacuum state in the Double Slit Experiment...

What bout Virtual Particles?

Why does an Interference Pattern Always have to be a " At 2 places at 1 time " conclusion?

P.S. - Can the Phenomenon of being at 2 Different Places at the Same Time also be seen as being at 2 Different Times at the Same Place???
🤔
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #33 on: 17/07/2021 01:44:12 »
Quote from: Zer0
Double Slit Experiment...Can the Phenomenon ... also be seen as being at 2 Different Times at the Same Place???
Absolutely! That is the classical "wave" interpretation of the double slit experiment.
- A wave has a certain velocity and a certain wavelength.
- The wave front takes two paths through the two slits to reach the screen at behind the slits (the "detector")
- At most locations (ie not exactly in the middle), it will take a different amount of time for the wave to propagate from each slit to a single point on the screen. This time delay produces a phase difference between the two paths.
- At some points, one wavefront will be delayed by an integer number of wavelengths, resulting in reinforcement (including the exact middle, where the delays are equal), 
- At some other points, one wavefront will be delayed by (an odd number of) half wavelengths compared to the other, resulting in cancellation
- Other places will be intermediate between these two extremes

So this is a case where a single point in space receives inputs at different times, reproducing the classical double-slit diffraction pattern.

It is easily demonstrated for photons, and macroscopic waves (>1026 atoms).
- It also has been demonstrated for individual atoms, but it requires much more careful experimental techniques!.
« Last Edit: 17/07/2021 08:20:45 by evan_au »
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Offline Halc

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #34 on: 17/07/2021 05:47:35 »
Quote from: Zer0 on 16/07/2021 23:27:48
I wonder how do they even get to a Total Vacuum state in the Double Slit Experiment
Most of the time they don't. Light for instance simply needs a transparent medium. Air works fine.
A vacuum is needed for massive particles like say neutrons.

Quote
Why does an Interference Pattern Always have to be a " At 2 places at 1 time " conclusion?
It doesn't. I don't conclude that. Light is not a classic wave, even though a wave model nicely predicts the interference pattern, at least until you start emitting single photons at a time.

Quote
Can the Phenomenon of being at 2 Different Places at the Same Time also be seen as being at 2 Different Times at the Same Place???
Seems totally different. I was at Aldi Monday, and I was there again today. That's being at the same place at 2 different times, which doesn't seem to have anything to do with a double-slit experiment.
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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #35 on: 17/07/2021 18:13:12 »
Quote from: Halc on 09/07/2021 01:37:57
Sounds like you're in agreement with this other guy then. Science has no proof of anything. Proof is for the mathematicians. Science makes predictions based on evidence. It does not assert truth or demonstrate proofs.

I was never in agreement with him, I thought my words were clear.
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #36 on: 18/07/2021 00:30:25 »
Quote from: Halc
I was at Aldi Monday, and I was there again today. That's being at the same place at 2 different times, which doesn't seem to have anything to do with a double-slit experiment.
The interference pattern in the Double-slit experiment is related to:
- the wavelength of the light you are measuring (or the de Broglie wavelength of the matter you are measuring)
- The separation of the slits
- The distance to the detection screen
- The divergence of the beam and angle of incidence on the slits (bored chemist has been doing experiments with this with his laser beam): this affects the phase of the light entering both slits

I've never previously had reason to calculate the effective wavelength of a human (let alone The Halc)...
- So here goes...
- Assuming a mass of 70kg
- Approaching the Aldi turnstiles at 0.5m/s
- The de Broglie wavelength is given by λ = h/mv
- Which works out around 10-35 meters
- See: https://en.wikipedia.org/wiki/Matter_wave

Now the separation of the turnstiles at Aldi is about 1 meter, which is greater than the wavelength
- We can approximate the angular separation of the fringes as θ/d = 10-35 radians
- If the Aldi store is 50m long, the fringe separation on the back wall will be about 10-37 meters
- ie smaller than the Plank length, where (it is thought) some assumptions in quantum theory may no longer apply
- See: https://en.wikipedia.org/wiki/Double-slit_experiment#Classical_wave-optics_formulation

To get good diffraction fringes, it is best if the slit separation is within a half-dozen orders of magnitude of the wavelength you are using. This would imply that the turnstiles at Aldi would need to be positioned less than 10-29 meters apart.

To get good diffraction fringes, it is best if the wave enters the slits not too far out of phase, ie Halc would need to enter the store within about 10-37 seconds of his previous visit.

Also, to get diffraction patterns, the waves entering the slits must be coherent (effectively the same wave/particle), or at least entangled (the states of the two particles are linked, at a quantum level).
- Unfortunately, when Halc visited Aldi the next day, he had interacted with people, eaten a few meals, breathed in a bit of oxygen, breathed out a bit of carbon dioxide, etc, so it is no longer the same Halc who entered the store the day before.
- Any entanglement he may have had with the previous Halc has been lost through interactions with the environment
- He has "de-cohered"
- So you don't expect that Halc would form interference fringes with himself with a phase difference of 1 day

Finally, the turnstiles at Aldi have a counter, so they are a "measurement device", in quantum theory
- Placing a measurement device at one (or both) slits decoheres the wave, and banishes the diffraction pattern.

So I'm afraid that the Aldi turnstiles don't serve as a counterexample to the hypothesis
Quote from: Zer0
2 Different Times at the Same Place
I think this hypothesis is valid, since a phase difference is equivalent to a time difference
- And a phase difference produces the diffraction pattern

Quote from: multifaceted
I've heard similar augments before and they didn't convince me that the theory wasn't true.
The arguments above don't prove that Halc can't be in two places at once.
- It just shows that any such quantum effect is so stupendously small and unlikely that in practice it makes no possible difference to our everyday lives.

Don't let quantum theory decohere your reality... because in practice, reality decoheres quantum theory
« Last Edit: 18/07/2021 00:33:36 by evan_au »
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Offline Multifaceted (OP)

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #37 on: 18/07/2021 18:48:24 »
Quote from: Halc on 09/07/2021 01:37:57
Quote
I googled if there was a limit to how many memories a person's brain could store and I found an answer written by a neurologist that the answer was absolutely yes.
Interesting to try to demonstrate that. It seems actually a pretty outlandish claim to suggest otherwise, so I'd actually be more interested in hearing the counter-argument to it. Maybe we ditch the assumption that a given brain is confined to a reasonable volume in a human head.

Are you saying you think there's a limit to how many memories were can store in our brain or not?
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Offline Eternal Student

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #38 on: 18/07/2021 19:25:17 »
Hi multifaceted,

   I'm not Halc but just putting in my opinion anyway.

   Where are my memories stored?   Not all of them are in my head that's for sure.   I have pieces of paper stuffed into a few of my textbooks.   I don't bother to remember those things, I just know that if I'm looking for something about "the geodesic equation" then the text book will automatically put my previous work and memories in front of me when I need them.  I'm confident that I would automatically go to that text book, use the index and hence open up to the right page and have my bits of paper fall out when I need information about whatever it is... ("the geodesic equation" in my example).
    The volume of my head doesn't limit my memories, if anything does then it's the volume of the universe and the amount of materials within it that I can order in a way to retain a record of my memories.
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Offline evan_au

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Re: Do atoms exist in multiple places at once, 2 places or 1?
« Reply #39 on: 18/07/2021 23:25:50 »
Quote from: evan_au
the fringe separation on the back wall will be about 10-37 meters
PS: To detect the fringes, you need to measure the position of a typical 70kg/1.8m customer on the back wall to an accuracy of better than 10-38 meters.

If we assume that there are something like 10+37 fringes over a meter of rear wall, you really need to get at least 10 (and preferably 100) impacts in every fringe to detect that it is there. That means you need to run the experiment at least 10+38 times to get a statistically significant result.

I fear that firing 10+38 70kg humans into your typical Aldi* store would turn it into a black hole, and you will never get a result out.
*Other supermarket chains are available!
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