I What does the product part of Laughlin wave function mean?

George Keeling
Gold Member
Messages
181
Reaction score
41
TL;DR Summary
confused by product symbol with two subscripts
I am looking at the Laughlin wave function and it contains the term
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q$$
In Wikipedia the lower index on ##\Pi## is ##1\le i<j\le N## and there is no upper index. I'm not sure what either mean. For example would
$$\prod_{j<k}^{N}\left(z_j-z_k\right)^q=\prod_{k=2}^{N}\left[\prod_{j=1}^{k-1}\left(z_j-z_k\right)^q\right]?$$
(It seems that ##k## cannot be 1 because there would be nothing to multiply in the second product). I'm not sure what else the expression could mean.

For ##N=3## that would give ##\ \left(z_1-z_2\right)^q\left(z_1-z_3\right)^q\left(z_2-z_3\right)^q## I think.
 
Physics news on Phys.org
Yes, this is the meaning of that product symbol with two subscripts.
 
  • Like
Likes George Keeling, Demystifier and pines-demon
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
I am reading WHAT IS A QUANTUM FIELD THEORY?" A First Introduction for Mathematicians. The author states (2.4 Finite versus Continuous Models) that the use of continuity causes the infinities in QFT: 'Mathematicians are trained to think of physical space as R3. But our continuous model of physical space as R3 is of course an idealization, both at the scale of the very large and at the scale of the very small. This idealization has proved to be very powerful, but in the case of Quantum...
Thread 'Lesser Green's function'
The lesser Green's function is defined as: $$G^{<}(t,t')=i\langle C_{\nu}^{\dagger}(t')C_{\nu}(t)\rangle=i\bra{n}C_{\nu}^{\dagger}(t')C_{\nu}(t)\ket{n}$$ where ##\ket{n}## is the many particle ground state. $$G^{<}(t,t')=i\bra{n}e^{iHt'}C_{\nu}^{\dagger}(0)e^{-iHt'}e^{iHt}C_{\nu}(0)e^{-iHt}\ket{n}$$ First consider the case t <t' Define, $$\ket{\alpha}=e^{-iH(t'-t)}C_{\nu}(0)e^{-iHt}\ket{n}$$ $$\ket{\beta}=C_{\nu}(0)e^{-iHt'}\ket{n}$$ $$G^{<}(t,t')=i\bra{\beta}\ket{\alpha}$$ ##\ket{\alpha}##...
Back
Top