Measurement problem Definition and 80 Threads

[b]1. The problem statement: all variables and given/known Describe a Non-Local Expirement that will lead to the conclusion that a body is in fact in a revolving system and not a system of constant acceleration. Non-Local meaning that the expirement uses 2 measurement instruments at 2...

In the measurement ansatz below, must the state |O,ready> be orthogonal to |O,reads up> and |O,reads down>]? |+x> |O,ready> =1/(sqrt2)[|+z> + |-z>] |O,ready> (1) ---------→ 1/(sqrt2)[|+z> + |-z>] |O,ready> (2) --------→ 1/(sqrt2)[|+z>|O,reads up> + |-z>|O,reads...

A rectangular park has an area of five hectares (1 hectare = 10,000 meter square) The dimensions of the park on a map are 5 cm * 4 cm What is the scale of the map?

Not sure if anyone will be able to answer these questions but it would be good if someone would give it a shot. A friend recently explained the measurement problem to me and i thought of a few questions which he was not able to answer. A) Do animals count as observers, and can they cause...

Does anybody else besides Fra believe that quantum mechanics' Measurement Problem, Quantum Gravity, and Unification Program of all Forces are somehow related? Why and why not (pls. state or elaborate why you think or don't think so)?

In Quantum Mechanics, there are measurement problems and you have many interpretations like Copenhagen, Many Worlds, de Broglie/Bohm mechanics, etc. Are there also measurement problems in Einstein Special Relativity for instance? Can't we consider the following: Spacetime in Relativity is...

Question Suppose molecules are placed next to the slits that fluoresce when electron passes, emitting a photon that can be imaged. Explain why this is no better than direct illumination, and explain how the two-slit interference pattern is destroyed. My Answer In direct illumination, a...

Here is a relatively simple problem. I'm wondering if someone can give me their opinion on it or actually know experimentally if it is true. Here is the diagram: A flow of liquid (say water) is pumped through a pipe that has a reduction in diameter. You place a pressure gauge before...

I did some device that should be capacitor. when i try to measure capacitance I got some capacitance that varies like that:(1.5-2.5nF), but.. then i wanted to check resistance just for curiosity.. I got some result..it shows me 1.34MOhm. How it could be? As I understand it should be or...

In the two slit experiment there is an interference pattern generated whenever there are no detectors at the slits. This must mean that the wavefunction associated with the particles have not decohered. But the wavefunction must have interacted in some way with the barrier in order to produce...

Is it correct to say that a measurement occurs whenever a wavefunction interacts with a macroscopic object? If this is the case why does the wavefunction make a distinction between a photon detector and say a half silvered mirror used in quantum experiments. Both are macroscopic objects but in...

is this a correct way to describe the MP? It means that everything is everywhere doing everything in every possible state at all times, until something conscious looks at it, then, as a result of the observer, it takes a state, which is only subject to how the observer perceives it. We only...

The problem involves measurement in a quantum system with angular momentum. There are two parts I am struggling with. Apologies for the images, I tried to put it all in latex but failed! Part 1: http://i2.sqi.sh/s_1/1xo/part1.jpg I have found a long derivation in a book involving a...

In double slit experiment of electron, we see an interference pattern when we don’t know through which slit electron has passed and we don’t see an interference pattern when we know through which slit electron has passed. Now, to identify the slit through which electron has passed, we use...

Why does decoherence not fully solve the measurement problem? I know that must have been discussed here before a lot, maybe someone can me direct to a earlier thread or post that explains it well? I read some QM texts, but they mostly do not discuss decoherence. I know something with...

In order to stop hijacking https://www.physicsforums.com/showthread.php?t=361216", I'll restart a discussion here about the role of background assumptions and the conceptual aspects of scientific theories, in particular how the "measurement problem" fits in with quantum mechanics and its...

There has at times been expressions of hope that a theory of quantum gravity may help resolve issues such as the 'measurement problem' in quantum mechanics (Penrose, and Smolin I think, and probably others). Have any of the recent 'advances'/'new lines of study' towards a quantum theory of...

i tried to explain for some one how we can solve the measurement problem and i went like this imagine your self in a room and in this room you don't have any sense so you can't see hear touch smell or even taste but you have a prob attached to your brain but if you don't do the measure you...

Hi guys, I am currently undergoing some measurement with TCS230 light to frequency converter, its actually a cmos color sensor, so the measurement result was made in period measurement. For white the output was not almost the same, but actually according to bitmap resolution, the R,G,B value...

if there are two identical systems,in quantum mechanics(or any other theorem),according to schrodinger equation, they will evolve congruously.but from the instant of measuring,the evolution seems disobey its original principle----i mean the evolutions are not congruously any more. is that mean...

Hi, does anyone know whether any of the current approaches to Quantum Gravity shed any light on the measurement problem in quantum mechanics? Moreover have there been any attempts to consider the implications of the measurement problem from within either the string theory approach or the quantum...

Consciousness and "the measurement problem" Hello All, Just a reminder that I am not a physicist...but for those who closed my thread on power of the mind :-(((( , pleae share your views on this- http://en.wikipedia.org/wiki/Consciousness_causes_collapse and this-...

Hi All, I was thinking if we can use the concepts of Von Neumann;s games specially the zero-sum two person games and pay of matrix with related dominant strategies and Nash equilirbria as a mathematical and a conceptual tool to understand Measurement Problem as a "game" between...

This new paper on the arxiv, http://uk.arxiv.org/abs/quant-ph/0506228, proposes a solution of the measurement problem based on Smolin's idea of relational quantum mechanics. Suppose an electron is "observed" by some lab system. But the electron also "observes" the lab! Conservation of...

http://arxiv.org/PS_cache/quant-ph/pdf/0506/0506100.pdf Title: A New Ontological View of the Quantum Measurement Problem Authors: Xiaolei Zhang Comments: 37 pages. US Naval Research Lab memorandum report NRL/MR/7218--05-8883, paper to be presented at the Albert Einstein Century conference...

I would like to draw your attention to a thread, running on s.p.r., which is closely related to what has been discussed in the (now defunt) thread on the Measurement Problem: https://www.physicsforums.com/showthread.php?t=75679&page=1&pp=15 cheers, Patrick.

Blaise Pascal duplicated Torricelli's barometer using a red Bordeaux win, of density 984 kg/m^3, as the working liquid. What was the height of the wine column for normal atmospheric pressure? Would you expect the vacuum above the column to be as good as for mercury?

I've got a few questions here, is the non-local "communication" between 2 entangled particles instantaneous, or is it just simply faster than the speed of light? Is this communication simply part of their common wavefunction or is it somehow a physical signal which somehow travels faster than...

Hi, I am reading Brian Greene's new book "The Fabric of the Cosmos". In the book, Brian Greene talks about the Quantum Measurement Problem, different interpretations of QM, decoherence, etc... Rather than attributing the collapse of the probability wave to things like conscious or human...

Regarding the measurement problem in QM - clearly a charged and divisive subject - what is your take on this problem? [I hope this is appropriate for this forum.] I would like your vote on the solution to this problem. Decoherence, non-linear collapse due to gravity, multiple universes...