I Metrics and conformal transformations

FuzzySphere
Messages
13
Reaction score
2
Conformal field theory is way over my head at the moment, but I decided to "dip my toes into it," and I watched a little video talking about conformal transformations. Now, I know that in a conformal transformation, $$x^\mu \to x'^\mu ,$$ the metric must satisfy $$\Lambda (x) g_{\mu \nu} = g_{\rho \sigma} \frac {\partial x'^\rho}{\partial x^\mu} \frac {\partial x'^\sigma}{\partial x^\nu}.$$ From this I have been informed that we can derive the condition $$dx'^\mu dx'_\mu = \Lambda (x) dx^\mu dx_\mu .$$ I have tried using the condition on the metric to derive this, only to get to this condition: $$g_{\mu \nu} dx'^\mu dx'^\nu = \Lambda g_{\mu \nu} dx^\mu dx ^\nu ,$$ but I have one query: can we use the metric $$g_{\mu \nu}$$ in the $$x^\mu$$ coordinates to lower the indices of $$dx'^\mu ,$$ seeing as they are from a different coordinate system?
 
Physics news on Phys.org
FuzzySphere said:
the metric must satisfy Λ(x)gμν=gρσ∂x′ρ∂xμ∂x′σ∂xν.
I observe ' and without ' are upside down.
\Lambda g_{\mu\nu}=g'_{\mu\nu}=g_{\rho\sigma} \ (\partial x^{\rho}/\partial x'^{\mu}) \ ( \partial x^{\sigma}/ \partial x'^{\nu})
 
anuttarasammyak said:
I observe ' and without ' are upside down.
\Lambda g_{\mu\nu}=g'_{\mu\nu}=g_{\rho\sigma} \ (\partial x^{\rho}/\partial x'^{\mu}) \ ( \partial x^{\sigma}/ \partial x'^{\nu})
No, that is the transformation law for the metric, what I have is the coordinate representation of the pull back of the metric by the conformal transformation.
 
This is an alert about a claim regarding the standard model, that got a burst of attention in the past two weeks. The original paper came out last year: "The electroweak η_W meson" by Gia Dvali, Archil Kobakhidze, Otari Sakhelashvili (2024) The recent follow-up and other responses are "η_W-meson from topological properties of the electroweak vacuum" by Dvali et al "Hiding in Plain Sight, the electroweak η_W" by Giacomo Cacciapaglia, Francesco Sannino, Jessica Turner "Astrophysical...
In LQG and LQC there are solutions called "black to white transition". I'll add some references: (Rovelli)https://arxiv.org/abs/1905.07251 (Rovelli)https://arxiv.org/abs/2302.03872 (Rovelli)https://arxiv.org/abs/1803.06330 (Rovelli)https://arxiv.org/pdf/1802.04264 (Rovelli)https://arxiv.org/abs/2108.12823 https://arxiv.org/abs/2304.02691 https://arxiv.org/abs/2110.07589 https://arxiv.org/abs/2009.01788 https://arxiv.org/abs/1911.12646 https://arxiv.org/abs/1801.03027...
Hello everyone, I am seeking to better understand the conceptual foundations and potential consequences of "Two-Time Physics" (2T-physics), as developed by Itzhak Bars and others. My interest was sparked by a recent paper that attempts to explain anomalous results in particle physics (apparent superluminal propagation of virtual photons) within the framework of 2T-physics: Paper: https://arxiv.org/abs/2408.02696 Key quote from the abstract: *"...the problem... can be solved naturally...
Back
Top