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Author Topic: Does reality not exist until we observe it?  (Read 1714 times)

Offline Nilak

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Re: Does reality not exist until we observe it?
« Reply #25 on: 03/10/2016 09:12:29 »
In the delayed choice quantum eraser the photon is basically detected without any interaction or any energy lossless. The which way path is determined observing its twin. The problem is that since the twin pair is entangled when you do a measurement on one photon it affects the other. Now here comes another trick. They let the first twin hit the screen, and let the other free to fly further without any measurement. After a while ( some ten ns) they decide to make a measurement. Guess what? The photon goes back im time and takes a the route they actually detected.
My opinion is that for some reason photons that interfere cannot be detected and when they reach the screen they are filtered as background radiation.
The fact that the observer disturbs the measurement is acceptable. The measurement on the twin particle disturbing the interference is very weird, plus  entanglement we know  is about the spin not the wavefunction. But then photons going back im time or predicting the future! ? That is almost absurd. But if it is actually what happens then the implications get very exciting.
 

Offline alancalverd

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Re: Does reality not exist until we observe it?
« Reply #26 on: 03/10/2016 10:21:12 »
Quote
the photon is basically detected without any interaction
Amazing. Please describe a detector that does not require any interaction or energy exchange with the object detected. (Remember to patent your device before publication).

Here's a simple event. Hydrogen fuses to produce helium and releases several gamma rays at once from the sun. An observer on earth detects some gamma radiation 8 minutes later. An observer on Mars sees some 15 minutes later. An observer orbiting Betelgeuse sees one 650 years later. How did the hydrogen atoms know when to fuse?
« Last Edit: 03/10/2016 10:29:02 by alancalverd »
 

Offline Nilak

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Re: Does reality not exist until we observe it?
« Reply #27 on: 03/10/2016 14:33:50 »
Quote
the photon is basically detected without any interaction
Amazing. Please describe a detector that does not require any interaction or energy exchange with the object detected. (Remember to patent your device before publication).
the photon is split in two after passing the slits by a barium borate crystal. Then chosing to detect or not one twin changes the wavefunction of the other. Simultaneity is not required.


Quote
Here's a simple event. Hydrogen fuses to produce helium and releases several gamma rays at once from the sun. An observer on earth detects some gamma radiation 8 minutes later. An observer on Mars sees some 15 minutes later. An observer orbiting Betelgeuse sees one 650 years later. How did the hydrogen atoms know when to fuse?
Sorry, I can't see the analogy of your example with the DCQE experiment.
 

Offline alancalverd

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Re: Does reality not exist until we observe it?
« Reply #28 on: 03/10/2016 15:28:15 »
One photon in, two photons out, means that energy has been exchanged. But suppose that we have in fact generated two photons each with half the initial energy. Detect one, and you have absorbed half the energy.

MY example demonstrates that simultaneity of event and observation is not requied.
 

Offline Nilak

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Re: Does reality not exist until we observe it?
« Reply #29 on: 03/10/2016 19:03:44 »
... Another is the introduction of "consciousness" into discussions of science, particularly if it is used without definition...

We don't quite need a good definition. It is simply a human watching a result on a display of a detector versus s  not watching the display but detector and display still plugged working.

Ps.
The fist simplistic definition useful im QM context was stated by Neumann. It basically says, that a device can make a measurement and then display the result. To read the result, you can use another device but it will still display its own measurement and so on. Human are capable of doing the measurement, but also to be selfaware of their own measurements. However, there are more recent experiments which demontrate that the wavefunction collapses when the "which way" is determinable regardless of a human mind being aware of the measurement.
« Last Edit: 04/10/2016 18:42:56 by Nilak »
 

Offline Nilak

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Re: Does reality not exist until we observe it?
« Reply #30 on: 03/10/2016 20:05:43 »
One photon in, two photons out, means that energy has been exchanged. But suppose that we have in fact generated two photons each with half the initial energy. Detect one, and you have absorbed half the energy.

MY example demonstrates that simultaneity of event and observation is not requied.
I understand something elese from this experiment.
Imagine you let a snowball roll down a hill. There are two initial ditches (A and B) that lead to two gates. Each gate is fitted with a blade that cuts the ball into two equal parts. Then they roll down through one of  another 4 short ditches (d1 and d2 for Gate A and also e1 and e2 for B) then the ditches become flat. Down lower at 100m there are two gates (GAand GB) that catch the ball if the ball went  through d1 or e1. The other half goes through d2 or e2 and after 200m reaches a man, at a position m2 for path A or another man n2 if it came through path B. The man that is at m2 or n2 is not allowed to whatch the ball until it reaches him. If the man at m2 or n2 decides to watch the ball then the other ball always gets caught into GA or GB.Otherwise they spread out all over the place.
For path A the ball will always get to man m2 and for path B always to man at n2.
For me the fact that the ball is split into two makes no difference anymore because it doesn't influence  the which path at all.
 

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Re: Does reality not exist until we observe it?
« Reply #30 on: 03/10/2016 20:05:43 »

 

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