Register to reply

Understanding spin and axis in quantum entanglement

by San K
Tags: axis, entanglement, quantum, spin
Share this thread:
San K
#1
Nov15-12, 10:59 AM
P: 915
I don't have a good grasp of "spin along axis" topic, so pardon my dumb questions:

1. Does a photon/electron have a different spin across each of the 3 axis?

i understand that the spin of an electron/photon is not the same as that of, say, a ball

2. Gravity can distort time-space (and hence the axis?).

Alice is in a gravity free part of space-time. Bob takes the other entangled photon and is in a space-time region that is distorted by gravity.

If Alice measures the spin of her entangled photon along say the "x-axis"

how does Bob figure out what his "x-axis" is? does Bob simply make adjustments for the new Cartesian system based on the formulas (for distortion of space time by gravity)?

3. If a photon is travelling along x-axis, does it have one spin each for each of the three axis? thus a total of 3 spins....if you are making calculations in the Cartesian system
Phys.Org News Partner Physics news on Phys.org
'Comb on a chip' powers new atomic clock design
Quantum leap in lasers brightens future for quantum computing
Enhanced NIST instrument enables high-speed chemical imaging of tissues
Bill_K
#2
Nov15-12, 11:27 AM
Sci Advisor
Thanks
Bill_K's Avatar
P: 4,160
If Alice measures the spin of her entangled photon along say the "x-axis", how does Bob figure out what his "x-axis" is?
Good question. Bob's particle must be noninteracting until it is measured. In a curved spacetime this means the particle follows a geodesic, and its spin axis is parallel transported. So although each of Bob's axes x, y, z may not be "the same" as Alice's, they correspond uniquely to those of Alice.
San K
#3
Nov15-12, 11:58 AM
P: 915
Quote Quote by Bill_K View Post
Good question. Bob's particle must be noninteracting until it is measured. In a curved spacetime this means the particle follows a geodesic, and its spin axis is parallel transported. So although each of Bob's axes x, y, z may not be "the same" as Alice's, they correspond uniquely to those of Alice.
well answered, thanks Bill


Register to reply

Related Discussions
Quantum entanglement of spin along multiple orthogonal axes Quantum Physics 4
Spin and entanglement Quantum Physics 7
Quantum Entanglement: Questions Quantum Physics 4
Some basic questions about Quantum Entanglement Quantum Physics 0
Earth's axis of spin w.r.t. galactic rotation axis Astronomy & Astrophysics 6