Measurement Problem in Quantum Mechanics #physics

What is the measurement problem in Quantum mechanics? In this video I discuss the various interpretations related to it - Hidden Variables, Copenhagen Interpretation, Many Worlds Interpretation. What is the wave function collapse? In this video I discuss this Measurement Problem of Quantum Mechanics, and it's philosophical implications.

[fluo]

As my quantum mechanics teacher said "nature doesn't care about what we think"

[nihilisticboi]

The hidden variable theory, although seems extremely obvious and intuitive, has been disproved experimentally by violating bell's inequalities. This means that, before measurement, we cannot assign any definite values to observables. This, which is crazy, means that if we consider position, then before measurement, the particle never had a definite position. Truly absurd.

[deadpoolgaming]

*I don't know why but my heart & mind can not accept the idea of many world interpretation, or parallel universe*, ,,, yes, there are experiments that explain something about it, but i am suspicious person when it comes to parallel universe, , , ,

[LesCish]

"Quantum" by Manjit Kumar covers a lot of the history of quantum mechanics and the disagreement of Bohr and Einstein over the Copenhagen interpretation. Fascinating book, highly recommended. I am NOT expert but felt neither quite got it right. As noted here there are alternatives to Copenhagen.

[gudgodgal]

Bhaiya you are a great physicist .I saw your lectures .Those are great.Thanks.

[lastchance]

The problem is that "particles" are not particles until observed. It's all just waves and vibrations until superpositions settle into a peak or trough which we define as the "particle". This is why crazy things like tunneling are observed.

[advaitrahasya]

When "interpretations" of a Mathematical Model (even one called a "theory") produces woo, one most likely has a wrong paradigm.

Why are physicsts not taught the history of Geocentric Epicycles?

Understanding the "quantum" phenomena is as easy as understanding planets going retrograde … if one escapes the wrong/inverted paradigm of Time-centeredness (persistence of matter) and Atomism (empty-space-ism).

[quantumentanglementsolved]

Bell’s mathematical theory didn’t take into consideration the wave function collapse, thus it didn’t disprove any written claim that one can quote. As long as the state remains the same, I don’t think Albert Einstein will disagree that the angle or spin orientation can slightly change due to the orientation of the measuring device.

[jonbold]

None of the particles you would like to study could exist without the medium of the galaxy supplying it with energy, constantly. When measurement interferes with the particle it is because measurement interferes with the medium. See Double Slit for a good example. You cannot have waves without a medium.

[ernestoduenas]

I woul say there's a especial perspective you need and this perspective is get by changing our position.

[SuicideRedemption]

Something that everyone seems to disregard, is the fact that measurement is not an absolute problem in quantum mechanics, rather we accept that the act of measurement seems to be equivalent to applying an operator to a system, that reduces its state to one of the eigenstates of that particular operator, but there is no direct connection between the act measurement and the process of applying the operator, it's a representation, and a pretty good one at that.I think that figuring out the effect of the phase factors that pop out when changing basis contributes to solving the measurement problem

[MrAzizisse]

Nice explanation. But the problem is what particle are we talking about ? How smal is it ? How did these formula come to existance ? By meaurements and observations ? How do u verify their accuracy ? How to measure these things, and using which equipment ?

[gosborg]

Or perhaps mankind doesn’t (yet) have the intellectual capacity to fully comprehend the true nature of reality at the quantum scale.

[subhajitpodder]

Local hidden variable theories are incompatible with Quantum Mechanics. Well, here is an outstanding paper by David Mermin which everyone without physics background can understand - " Is the moon there when nobody looks ?! "

[garrett]

QM is at the Newtonian level. A good formula that makes predictions and explains observations. But Newton knew it was incomplete and it was Einstein who discovered General Relativity which explains how gravity actually works. We need to figure out how QM actually works.

[baronvonbeandip]

Please turn the music down or at least gainstage it to a point where it's not louder than your voice.

[surprisemokwena]

Why would you want to know both the momentum and position at the same time. Who cares where a random particles is and it's momentum I'm real time. If you can predict the overall evolution of the quantum system in question

[David-xvye]

Wasn't it recently proven that matters not locally real? I believe they got a Nobel Prize.

[JoshVandever]

In the many worlds interpretation, the other universes are part of our universe.

[Krisoler]

According to the Pilot Wave interpretation in the double slit experiment, a photon passes through one slit, but the wave travels to the other slit, passes through it, and then returns to the path of the photon to interfere with the wave that passed through with the photon in the first slit, for which it must have traveled faster or slower than light! Or is it the wall of the slits that vibrates naturally and generates the waves that interfere and guide the path of the photon? Are they gravitational waves that deform space-time, and the photon follows a geodesic of its minimum proper time?

In the Copenhagen interpretation, the wave front arrives first in the central area of the screen, and then arrives delayed at the edges of the screen, so one might wonder how the wave decides at what moment to collapse? Because it is not only at what point it decides to collapse, but also at what moment. In wave collapse, all the energy of the wave is transported instantly at infinite speed to a single point on the screen, but according to the uncertainty principle, the shorter the time, the greater the energy, therefore an instantaneous time implies infinite energy!

In the many worlds interpretation every time there is a "measurement", does the universe double in energy, mass, space and time? How many "measurements" have occurred in the history of the Universe? How many universes exist? How does our body, which has grown for decades, instantly duplicate all its cells and molecules?