Section 8

Question 1

Is the wave-function real, or just a mathematical artifact

Answer 1

The Aharonov-Bohm effect confirms that it is real

Question 2

quantum Measurement problem

Answer 2

measurement gets to be a sharp, non-unitary process

does consciousness have to be involved? How would we justify that

Question 3

P(i) =

Answer 3

|c(i)|^2 = 100%

Question 4

if we make continnual measurements

Answer 4

the system is continually reset into state |i>, and cannot time-evolve

Question 5

Quantum interrogation

Answer 5

has been shown to be real via Raman spectroscopy, stimulated 2-state atomic systems

Question 6

Schrodinger’s Cat

Answer 6

cat in a box with a quantum-triggered poison

fate of the cat depends on a quantum phenomenon

Question 7

the density operator

Answer 7

p(hat)ij = |φ(i)><φ(j)|

Question 8

<p(ij)>(many) ∝

Answer 8

(|a|^2 0)
( 0 |b|^2)

where the off-diagonals have disappeared

Question 9

EPR paradox

Answer 9

if one part is measured, the other also collapses… faster than light? is physics non-local

Question 10

Entangled

Answer 10

an m(j) = 0 state decaying to two fermions is said to have entangled their spin state

Question 11

Hidden variables

Answer 11

QM is truly deterministic, we just can’t see the ‘controlling’ variables, so it’s probabilistic according to the visible information

Question 12

experimental tests confirm

Answer 12

the Copenhagen Interpretation over local HIB

But non-local HV QM remains possible: Bohmian Mechanics

Question 13

Measurement is largely understood via

Answer 13

the Copenhagen Interpretation as decoherence from coupling/entanglement of the micro and macro systems

Question 14

the density matrix is a key object for

Answer 14

understanding entanglement and decoherence. Statistical averaging washes out interference terms, preserves diagonal ‘classical’ states.

Question 15

Hidden variables theories constrained by

Answer 15

Bell’s Theorem

but non-locality still viable