Thread: Quantum Mechanics question: Is measurement really a continuum?

Hi!

So my degree is in computer science, I really don't have much physics beyond the high school level. But I recent watched this talk, from a computer scientist from Google:



He had big questions about Quantum mechanics, so he talked to some guys at Cal-Tech, and put together the above talk, with his own interpretation of QM which, as a CS guy myself, I really enjoyed.

But at 34:00 minutes in to that video, he makes a remarkable assertion: He says measurement is a continuum: The amount that a probability density function is collapsed happens along a continuum. This is counter intuitive from what I've previously read about QM, which is that for an individual particle, the probability function is collapsed or it isn't. So I'm thinking the math he points to says that probability really is a discrete rational number, not a real number, as he intreprets it to be.

Or maybe am I wrong. So my question is: it possible to partially observe a single particle in the two slit experiment, so its probability density function is somewhere in between the interference pattern and the normal distribution of a particle going through one slit???

I appreciate the patience and answers of any physicists here.

PEace!
Tridentblue.

For the prob density function. Toss a coin, toss again and again every time you dont get a tails the probability of getting a tails increases if you never get a tails the probability will increase continuously. Now you could collapse a function at a particular point and say I would never need a reading more accurate than that the point to make is that you could continuously make your reading more accurate to infinity or until your function replicates itself

Originally Posted by fiveworlds

For the prob density function. Toss a coin, toss again and again every time you dont get a tails the probability of getting a tails increases if you never get a tails the probability will increase continuously. Now you could collapse a function at a particular point and say I would never need a reading more accurate than that the point to make is that you could continuously make your reading more accurate to infinity or until your function replicates itself

Why is it not always a one in two chance of tails coming up? If the conditions are always the same then isn't the probability for the possible outcome always the same?

yeah ascended but its just an example to explain measurements towards infinity ones like distances, accurate measurement of pi etc. until we find an accurate means of solving for the distance etc we can try to make it as accurate as possible by taking hundreds of tangent points and finding the distances between them. by using means that we already know of to try and resolve the problem as best we can. Another example was the shot glass of whiskey how many times can you half a shot glass and still have whiskey in the glass (the number of molecules of whiskey/2)

Originally Posted by fiveworlds

For the prob density function. Toss a coin, toss again and again every time you dont get a tails the probability of getting a tails increases if you never get a tails the probability will increase continuously.

No it doesn't. The probability of the next coin being tails never changes.

Originally Posted by fiveworlds

Another example was the shot glass of whiskey how many times can you half a shot glass and still have whiskey in the glass (the number of molecules of whiskey/2)

Is "the number of molecules of whiskey/2" supposed to be your answer to that question? If so, it's wrong. It would be log₂(number of molecules of whiskey).

Originally Posted by fiveworlds

Toss a coin, toss again and again every time you dont get a tails the probability of getting a tails increases if you never get a tails the probability will increase continuously.

Please, go away and learn something.
The probability of tails never alters. Ever.

really so you say that you can never have a badly weighted or unfair dice a loaded pack of cards or factor which influence a coin toss? would you argue with fo=1/f too?

Originally Posted by fiveworlds

really so you say that you can never have a badly weighted or unfair dice a loaded pack of cards or factor which influence a coin toss?

That isn't what you said. (Let me give you a hand with those goalposts.) If the odds of tails is not exactly 50/50, it doesn't change the fact that the odds don't change as you toss the coin more often.

However often you toss the coin, the odds of the next one being tails is exactly the same as the first one.

would you argue with fo=1/f too?

What does that mean?

Originally Posted by fiveworlds

really so you say that you can never have a badly weighted or unfair dice a loaded pack of cards or factor which influence a coin toss?

Oh, moving the goal posts?
Your comment "Toss a coin, toss again and again every time you dont get a tails the probability of getting a tails increases if you never get a tails the probability will increase continuously" didn't specify a "loaded" coin, and therefore, by default, implies a "normal" one.
In which case you were, as stated by at least two people, incorrect.

And regardless, a "loaded" coin would still have exactly the same (skewed) odds of landing on tails. The fact that it landed on heads x number of times does not "increase the probability of tails with each and every toss".
If the initial odds are 70/30 then no matter how many times any given result comes up the odds remain at 70/30. Forever.

Please, go away and learn something.

what does what mean?

would you argue with fo=1/f too?

What does that mean?

i really havent the foggiest what are you talking about?

You made the comment "would you argue with fo=1/f too?"
What does it mean?

maybe you should go and learn nothing

Originally Posted by fiveworlds

maybe you should go and learn nothing

Maybe you should stop making meaningless posts.
If you can't explain what you mean why bother saying anything?

im listening go on whats wrong?

"fo=1/f"

What does that refer to?
How is it relevant ot the rest of the conversation?

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Originally Posted by fiveworlds

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What is wrong with you? What is that supposed to mean? Is it possible for you to try and communicate like a normal human being?

What does, "fo=1/f" mean?

And will you admit you were talking nonsense about tossing coins?

perhaps you arent quoting me correctly try again

Originally Posted by fiveworlds

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Is that better? It's still some kind of diagram that has no explanation. Instead of speaking in riddles, go for clarity and understanding.

Originally Posted by fiveworlds

perhaps you arent quoting me correctly try again

And perhaps you're being deliberately obtuse.
You have been quoted in full at least four times. Posts #8, 11, 13 and 19.
Once more "would you argue with fo=1/f too?" Post #7.
What does that refer to?
How is it relevant to the rest of the conversation?

nope just the diagram ever heard of a fractal???

How is it relevant to the rest of the conversation?

relative frequency(maths)=1/chance of occurances(frequency)
fundamental frequency(physics)=1/a period.
So define a period as the max number of points a wave travels through and hey presto its chance of occurances

Originally Posted by fiveworlds

relative frequency(maths)=1/chance of occurances(frequency)
fundamental frequency(physics)=1/a period.

Ah right.
In other words nothing whatsoever to do with the conversation. And nothing to do with your "diagram". Or fractals.
Got it.
All coupled with (at least) two fundamental misunderstandings on your part.

Wanna try for more nonsense?

you have no idea what you are talking about why dont you explain instead of complaining. is a fractal not a continuous equation or can you solve one id like to see you solve ONE accuately. as for nothing whatsoever to do with the conversation this is about collapsed functions and why some equations are continuous and collapsed at a certain point i am far from qualified to awnser the experimental double slit experiment question and i dont have the apparatus to test it. you could possibly solve a fractal curve to a cerain degree of accuracy but you know that there is a high probability for inaccuracy in your measurements.

Originally Posted by fiveworlds

you have no idea what you are talking about

That would be you.

is a fractal not a continuous equation

No.
A fractal is "a mathematical set".

as for nothing whatsoever to do with the conversation this is about collapsed functions and why some equations are continuous and collapsed at a certain point i am far from qualified to awnser the experimental double slit experiment question and i dont have the apparatus to test it

Ah right. You post about "collapsed functions" in reply to a comment on probabilities (which you misunderstand). How is it relevant?
To quote Strange: "And will you admit you were talking nonsense about tossing coins?"

what i never lose coin toss so whats 50/50?

Originally Posted by fiveworlds

what i never lose coin toss so whats 50/50?

What?
Could you please try to be coherent when posting?

i read benoit b mandelbrot

If you aren't going to make coherent replies I'm not going to respond in future.

Wow, hell of a thread. It sounds like people are talking about Gambler's Ruin. That may have been a hint as to the answer of my question, but I didn't totally understand it. My question is this:

If single photons are fired into two slits, with no observation as to which slit they go through, the probability density function for where each one lands is given by the interference pattern. But if we observe which slit the particle goes through, that goes away, and the probability density function is not defined by such a pattern. The talk I linked to seems to imply that the probability of the slit detector working can serve to partially get rid of the interference pattern for a single particle, so the interference pattern partially collapses, leaving something in between it and the more normal pattern. But that seems inconsistent with other things I've read.

Maybe its not a meaningful question, because we are talking about probability spaces, and many trials. But I'm trying to get an intuitive picture of this science. Is the collapse of the probability space something which ( for an individual particle) absolutely happens (represented by a boolean true/false value) or not (represented by some number between 0 and 1)?

hmm im not really sure perhaps waveform polarisation?of course you still have the problem that in observation of a particle you have bounced light off a particle and therefore altered its position and velocity. also how thin can you make a slit it would not be a single particle wide also you have to take into account that your particle passes through the magnetic field of the atoms in the slit. if the slit is too small the particles will be reflected or diffracted. So what they really want is just small enough to allow one particle through so miniscule. Do they just want a particle? its easy to observe electons on a oscilloscope. You can also shoot them at a flourescent material to make it glow ie a monitor. The old ones are cathode ray tubes ie electron gun. One can assume that it takes a certain amount of energy to produce colour. What about saying something like white was produced so therefore it must have a specific wavelength and frequency? it was also prodced in an atom and it should be possible to know the kinetic energy of the electron or atom before it hit the screen. v=I/R sound familiar? In a cathode ray tube electrons are accelerated across a high potential difference through a magnetised circular slit. the path of these electrons is then controlled by a magnetic field which causes them to deflect towards their intended pixel this pixel is made of a material which when struck by the particle emits light. Now from bohr theory we can assume that the drop in energy level of the atom corresponds to the kinetic energy of the incident particle/s. Now if you concentrate this light on a glass prism it is separated accordong to its line spectrum and its wavelength is measureable in nm. you can also find the wavelength before the collision using an oscilloscope graph. Dywyddyr coherent hmm i wouldnt know what is incoherent?

Originally Posted by fiveworlds

of course you still have the problem that in observation of a particle you have bounced light off a particle and therefore altered its position and velocity.

Well, the thing is we're talking about photons to start out with. I read they are something called "Bosons", not "Fermions", so they can exist in the same place at the same time without effecting each other: Basically that means light "particles" don't collide: You point to laser pointers so that they intersect, and they don't scatter out from collisions, (like two streams of water would) they remain unchanged. So the ways they use to observe the slit is more subtle, and very passive.

That was my first thought when a hippy told me about quantum mechanics though, that measuring very small things must effect them, by like bumping in to them. The experiment that made me see that was wrong was called "Quantum erasure". It says that if you measure the particle, and erase the measurement instantly after the particle is as if you never measured it. But if the measuring particle was "bumping in" to things, that wouldn't be true, the damage would be done.

Its frustrating. It would take me years of study of things I'm not that interested in to really get to know QM, but it raises fundamental questions about the nature of ultimate tiniest nature of reality I would like answered. Somebody needs to put together a "do it yourself two slit experiement", with all the math included (as computer programs with code) so people can just look at it themselves.

what if the bosons in the light interacted as passing each but because of their speed it made no difference? and the two slit experiment program exsists unfortunately i dont remember the name

Originally Posted by fiveworlds

hmm i wouldnt know

That's increasingly evident.

what is incoherent?

Your posts.

does the speed of light in a medium change from one medium to another? does the speed of your photon change from one medium to another then you could determine wether it is completely unaffected. can you fire a photon through fifty inches of lead? if not it isnt completely unaffected.

Originally Posted by fiveworlds

does the speed of light in a medium change from one medium to another? does the speed of your photon change from one medium to another then you could determine wether it is completely unaffected. can you fire a photon through fifty inches of lead? if not it isnt completely unaffected.

No, it does not.

i would think it is more likely that photons induce a cherenkov like effect it obviously loses momentum over time otherwise when i turn off my light it would stay bright

Originally Posted by fiveworlds

i would think it is more likely that photons induce a cherenkov like effect it obviously loses momentum over time otherwise when i turn off my light it would stay bright

Originally Posted by fiveworlds

i would think it is more likely that photons induce a cherenkov like effect it obviously loses momentum over time otherwise when i turn off my light it would stay bright

That's a poor experiment for something that moves at about 300,000 km per second.
The photons are either absorbed or enter a lower energy state, being infrared or radio waves. At the speed photons move, they can reflect off objects many, many times before they are absorbed and it will still happen so fast that it appears instantaneous to us.

Well, I found a cool computer program that simulates it:
Quantum Wave Interference - Quantum Mechanics, Photons, Electrons - PhET
Its a java program you can run: It lets you see the wave interference pattern from a laser, and adjust it. You can also add a detector to one of the slits (bottom right in the interface) which lets you see it collapse. You can also fire single particles at it, and watch the same behavior hold.
Unfortuantely, it doesn't answer my question. The math the Google guy talked about the idea that measurement could be a continuum, so you could just partially measure, and get a partial loss of the interference pattern. Is that true for just one particle? Can you just partially measure one particle? Or is it actually talking about many particles? (Some will be measured, some will not, so you get a mix of both output patterns)

Problem is, I'm not sure these two results would look any different, now that I think about it.

Anyway, thanks for all replies.

Originally Posted by TridentBlue

Or maybe am I wrong. So my question is: it possible to partially observe a single particle in the two slit experiment, so its probability density function is somewhere in between the interference pattern and the normal distribution of a particle going through one slit???

In short no. First of, to make such an experiment would be a weird experiment. It would require you to manipulate your experiment is such a way that the values would come out. Which basically means changing the location of the detectors. This is weird, as there is a finite but non-zero probability that a wave interaction would make a particle observation hit. It is after all a statistical experiment. We only see it after a long time of many detections. The experimental realisation of this question is the "Quantum Eraser" experiment. There is no 'partially' anything. Observations dominates one of the two. Or both. No exceptions.

Let me look at the video.

To start of, the presenter isn't a nut-case at all. He is probably very capable. However his explanation of the implementation of the quantum eraser experiment is not complete. It is one of the ways of doing it, but it has been discussed to be far from pure and not accurate enough. The quantum dot variant actually erases the (quantum) information.
*Blatant typo at 0:20:30 :P

He makes a small mistake in his reasoning which is on the other hand rather crucial. He assumes that his detectors belong to the same Hilbert space. Since both detectors observe a different (but the same) particle set-up, yet are not both part of the same quantum system. That cannot be done. This means that the the two state (upper and lower) detector might be pure in their own hilbert space. We'd first need to prove that the detectors do not have an overlap of their congruent Hilbert spaces.
And of course they do not, as we know they are both coupled to the same observationa particle. Hence their overlap is finite. However the overlap should be invariant of choice and hence disappear. I don't see any wrong in his arguments. Albeit they are simplified.

It is a very nice video though. Though I don't see why he would state the Copenhagen interpretation to be untenable. I have not really encountered that problem.
The reason why the polarizes experiment was ditched, was indeed for his argument. But the new set-up is invariant of this.

Originally Posted by Ascended

Why is it not always a one in two chance of tails coming up? If the conditions are always the same then isn't the probability for the possible outcome always the same?

Here is the analogy I tell my students:

I have three cups. Beneath one of the cups (you don't know which one) is a ball. You win a prize if you guess it right. I ask you to point out a cup. After pointing out a cup. I point out another cup, and tell you. 'The ball isn't underneath this cup'. Question is, do you change?

Think about it.

Spoiler Alert, click show to read: 

The answer is of course YES! you switch for the other cup has a larger probability of being the right cup. Here is how it works:
At the beginning You have no information about the set-up of the cups. (Just like in an experiment) So your odds are a statistical 1 in 3.

However

After I point out one of the cups, I introduce additional knowledge to the system. There is two possibilities:
1. you are already pointing out the ball. In that case my choice of pointing out which cup is of not additional relevance.
2. You are in fact not pointing at the ball. Then for me, there is only 1 cup I can choose that isn't the cup with the ball beneath it. I have quite literally collapsed the system because by doing so, I have reduced the problem to two cups.

In doing so I have changed the odds as follows:

To change makes your odds:
1/3 chance of scenario one -> you are right, and I know => Switching: you lose. Not switching: you win
2/3 chance of scenario two -> you are wrong, and I know => Switching: you win, Not switching: you lose

In other words, switching gives you a 2/3 chance of winning. So you should always switch!

And 4/9 > 1/3. Using the information given is increasing out possibility to win. Even without us chosing. So, why switch?

And this is how it works with quantum mechanics too. Quantum mechanics isn't that science of what is known, but what is unknown and making predicitions of what can be known. Adding and recording usefull information changes the outcomes of experiments. However not using such records do not change the outcome. This is because observations (previous) that I can know and recal, change my probabilities. And so it is with a (non-markovian) coin. If I know I just had 300 heads, I know that the chances of a tails are a bit larger (not by much though). It is a strange way. But fact of the matter is, that it works.

Originally Posted by Kerling

Originally Posted by TridentBlue

Or maybe am I wrong. So my question is: it possible to partially observe a single particle in the two slit experiment, so its probability density function is somewhere in between the interference pattern and the normal distribution of a particle going through one slit???

In short no. First of, to make such an experiment would be a weird experiment.
(snip)

However his explanation of the implementation of the quantum eraser experiment is not complete. The quantum dot variant actually erases the (quantum) information.

(snip)
Though I don't see why he would state the Copenhagen interpretation to be untenable. I have not really encountered that problem.
The reason why the polarizes experiment was ditched, was indeed for his argument. But the new set-up is invariant of this.

Wow, thank you so much for such a lucid and well informed reply, I deeply appreciate it.

That the experiment might be too weird crossed my mind. The math is basically probabilistic, and talking about the probabilities for a large number of events.

I take from your words that different versions of the quantum eraser experiment have been done. Do you happen to have a link for the "quantum dot variant" you refer to? To me the quantum eraser experiments, even more than Young's double slit experiment underscore the weirdness of the quantum world, so I'm very curious about them.

I DO understand why he proclaims the Copenhagen interpretation to be untenable, but I think its based on a misunderstanding, that "measurement is a continuum", as in the "interference pattern probability distribution can be partially collapsed for a single particle". The math he presents is ambiguous in this regard, as to whether its refering to a collection of events, or a single one. If its refering to a collection of events where the interference pattern is either collapsed or not based on some other probability, (as you say it is) the Copenhagen interpretation is fine. But otherwise, its very muddy:

"A system is completely described by a wave function , representing the state of the system, which evolves smoothly in time, except when a measurement is made, at which point it instantaneously collapses to an eigenstate of the observable measured."

(from Copenhagen interpretation - Wikipedia, the free encyclopedia)

Anyway, thanks again for your lucid reply. Any wisdom, links, or anything else you can contribute to my attempts to gain a better intuitive understanding of QM are greatly appreciated.

PEace!

Originally Posted by TridentBlue

I take from your words that different versions of the quantum eraser experiment have been done. Do you happen to have a link for the "quantum dot variant" you refer to? To me the quantum eraser experiments, even more than Young's double slit experiment underscore the weirdness of the quantum world, so I'm very curious about them.

I personally studied several. I believe path interference experiments were done buj Vincent Jacques PRL 100, 220402 (2008) and Vincent Jacques SCIENCE Vol 315 p966 (2007)
I believe the article of Yoon-Ho Kim PRL Vol 84 Number 1, is a dot-eraser. Which is most easily explained by Ingraham in PR A, volume 50 no. 6 (1994).
It basically boils down to choosing to see which of the two dots the photon came from or not.

I DO understand why he proclaims the Copenhagen interpretation to be untenable, but I think its based on a misunderstanding, that "measurement is a continuum", as in the "interference pattern probability distribution can be partially collapsed for a single particle". The math he presents is ambiguous in this regard, as to whether its refering to a collection of events, or a single one. If its refering to a collection of events where the interference pattern is either collapsed or not based on some other probability, (as you say it is) the Copenhagen interpretation is fine. But otherwise, its very muddy:
"A system is completely described by a wave function , representing the state of the system, which evolves smoothly in time, except when a measurement is made, at which point it instantaneously collapses to an eigenstate of the observable measured."

I yes, I see the problem now (I think) the predicitions are indeed a continuum. But they are still a probability continuem. What happens at a single measurement is still a decay, making a probability reality. But that is really what probability is about.

If you like a good piece to read, read:
Three measurement problems - Springer
Tim Maudlin makes a very simple and consice clarification of the measurement problem.

Originally Posted by Kerling

I personally studied several. I believe path interference experiments were done buj Vincent Jacques PRL 100, 220402 (2008) and Vincent Jacques SCIENCE Vol 315 p966 (2007)
I believe the article of Yoon-Ho Kim PRL Vol 84 Number 1, is a dot-eraser. Which is most easily explained by Ingraham in PR A, volume 50 no. 6 (1994).
It basically boils down to choosing to see which of the two dots the photon came from or not.

I yes, I see the problem now (I think) the predicitions are indeed a continuum. But they are still a probability continuem. What happens at a single measurement is still a decay, making a probability reality. But that is really what probability is about.

If you like a good piece to read, read:
Three measurement problems - Springer
Tim Maudlin makes a very simple and consice clarification of the measurement problem.

Thanks for those resources, I look forward to reading them. And yes, a lot of my difficulty understanding comes from the way probability is. Its defined at the most basic level as successes/trials, but can there be such a thing as probability at an instant? For instance, is the expected value of two fair dice (7) meaningful if you only role them once, or does it only gain meaning over many trials, through the Law of Large Numbers?

This is really a philosophical question to me about what probability really means, the math is pretty clear. It just seems that quantum mechanics is so hard for me to really get my head around because at a deep level, the concept of probability - as something fundamentally real - is hard to really my head around.

But anyway, thanks again for your responses.

Originally Posted by TridentBlue

Thanks for those resources, I look forward to reading them. And yes, a lot of my difficulty understanding comes from the way probability is. Its defined at the most basic level as successes/trials, but can there be such a thing as probability at an instant? For instance, is the expected value of two fair dice (7) meaningful if you only role them once, or does it only gain meaning over many trials, through the Law of Large Numbers?

This is really a philosophical question to me about what probability really means, the math is pretty clear. It just seems that quantum mechanics is so hard for me to really get my head around because at a deep level, the concept of probability - as something fundamentally real - is hard to really my head around.

For your probabilities check out post 45.
About this I had a discussion a few weeks ago with my colleague. Using probability to understand quantum mechanics is of course required. But most people have the wrong approach. They take it as a requirement to figure out what it is that we know. But that isn't what quantum physics is about. Quantum physics is more the science of what we do not, and can not know. Also for nature, probability is, what actually is (in the absence of knowledge). The particles don't only just have a probability for each path. They actually move over these paths with the same weight as their probabilities. But trying to see the world in probabilities is actually quite fun. Nothing is permanent nothing is perfect. And all of the sudden the world starts to make more sense. As I progressed in my quantum career, so did the quantum progress in my life. And my life got further and further away from yes and no, to some grey-scale continuum between yes and no. It really helped me solve my social problems, because there is little more quantum then the human mind.

Think about it

Originally Posted by Kerling

For your probabilities check out post 45.
About this I had a discussion a few weeks ago with my colleague. Using probability to understand quantum mechanics is of course required. But most people have the wrong approach. They take it as a requirement to figure out what it is that we know. But that isn't what quantum physics is about. Quantum physics is more the science of what we do not, and can not know. Also for nature, probability is, what actually is (in the absence of knowledge). The particles don't only just have a probability for each path. They actually move over these paths with the same weight as their probabilities. But trying to see the world in probabilities is actually quite fun. Nothing is permanent nothing is perfect. And all of the sudden the world starts to make more sense. As I progressed in my quantum career, so did the quantum progress in my life. And my life got further and further away from yes and no, to some grey-scale continuum between yes and no. It really helped me solve my social problems, because there is little more quantum then the human mind.

Think about it

Checked out post #45. WOW! What the hell. I had to write up a script to test that, but sure enough it pans out. 66% for switch, 33% for non switch. And suppose you pick a cup, and the cup you are told doesn't have the ball can include the cup you picked... Well then, you only have a 50% chance of winning with that info. So you have more information by having information about the cup you chose excluded! What - the - hell. Very counter intuitive.

I'm glad to hear you talk about about how you've applied the philosophy of probability to your life. I'm drawn to it because the philosophical ramifications, the same with quantum mechanics: The physics of the foundations of the universe seem meaningful in terms of the general question about the nature of the universe we live in, with broad applications beyond the explicit physics. I see that most strongly in the quantum mechanics ideas - you said it well:

Quantum physics is more the science of what we do not, and can not know. Also for nature, probability is, what actually is (in the absence of knowledge)

What actually is, in the absence of knowledge. What a profound statement. I am struck by the idea that we have these brains, the information gathering systems - but at a certain level of inquiry, the awareness becomes about these systems themselves. It becomes impossible to see the universe without acknowledging the unique corner of it which we occupy, and the status of our own knowledge and the extent to which it correlates, or does not, with what's actually out there. Its very difficult to look at these truths, to look at this world which exists as a collection of observers, without remembering so more ancient ideas, like the Buddhist concept of Indra's net:

Far away in the heavenly abode of the great god Indra, there is a wonderful net which has been hung by some cunning artificer in such a manner that it stretches out infinitely in all directions. In accordance with the extravagant tastes of deities, the artificer has hung a single glittering jewel in each "eye" of the net, and since the net itself is infinite in dimension, the jewels are infinite in number. There hang the jewels, glittering "like" stars in the first magnitude, a wonderful sight to behold. If we now arbitrarily select one of these jewels for inspection and look closely at it, we will discover that in its polished surface there are reflected all the other jewels in the net, infinite in number. Not only that, but each of the jewels reflected in this one jewel is also reflecting all the other jewels, so that there is an infinite reflecting process occurring.

what is probability ? In real term no probability exit in Universe neither at macro level nor at quantum level . Everything in space
including mass and energy what ever exits has properties and entire space works as a system. So no chance , what happen in past should must be happen in past.

Probability is a psychological phenomena as practically it is not possible to have complete knowledge of all aspects of events. We make guess based on knowledge/experiences we have. In tossing a coin, we have not complete knowledge what side will come, but with our best knowledge we guess both have chances as physically one of both can come. But actually only one will come based on different forces put on coin.

I say you have to tell from which country I belong ? I give hint- I live in Europe. Possibly there are many
countries in Europe. What probability do you give Germany ? Suppose 5% If I increase your knowledge &
give another hint- Where I live is in Western Europe. You will increase probability of Germany suppose 10%. I give another hint- Its border touche with Belgium. (France , Germany and Netherlands 's borders touch with Belgium) Now possibly you will increase Probability of Germany upto high level like 30% or 40%. But actually My locality is independent of your knowledge , it increases or decreases I would live in same country and no probability exist in real term.

In do not think if One side of coin comes , then next time probability of other side increases.

Originally Posted by RAJ_K

what is probability ? In real term no probability exit in Universe neither at macro level nor at quantum level .

At the quantum level, things can only be described in terms of probability.

Probability is a psychological phenomena as practically it is not possible to have complete knowledge of all aspects of events.

That is true at the macroscopic level. It is not true of quantum physics. There are no "hidden variables" which would give us more knowledge and make things deterministic.

Originally Posted by RAJ_K

In do not think if One side of coin comes , then next time probability of other side increases.

Not quite sure what you're saying here.
The probability always remains the same, regardless of what came last or how many times it came up the same.

My means to say if tail came two time , it will not make effect on next time and previous toss will not increase probability of other side.

Originally Posted by RAJ_K

My means to say if tail came two time , it will not make effect on next time and previous toss will not increase probability of other side.

Ah, okay.
I misunderstood, sorry.

@Stranger, How probabilities can exit at quantum world in real term? Is events occur here without
laws of nature? Probabilities can never exit at quantum level. It is impossible to believe it.

Yes , we have not complete knowledge and measurement system is too weak to measure a proper picture.
Probabilities Distribution is best way to measure things at quantum level and practically it is also not possible give
outcome of quantum actions wothout the help of Probability Distributions.

But this does not mean quantum world is free from laws of nature and things happen here without any reason.

Originally Posted by RAJ_K

@Stranger, How probabilities can exit at quantum world in real term? Is events occur here without
laws of nature? Probabilities can never exit at quantum level. It is impossible to believe it.

Like it or not, the "laws of nature" at the quantum level are purely probabilistic.

If it would be true , Then I will leave the science.
But it is not possible for me to believe.

If it would be true , Then I will leave the science.
But I am sure Its not possible.

I read a good article recently called something like, "Why quantum mechanics must be probabilistic." I'll see if I can find it.

But any good text on quantum physics should confirm it.