- #1
taitae25
- 10
- 0
Hi there,
This is my first post and I am guessing I should post my question here at the astrophysics section so I'm doing so (admin, if you think the topic should belong somewhere else, please move it).
My question is with regards to the continued research conducted by Tajmar et al [1,4-7]. To answer the apparent, what seems to be an amplified effect of classical frame dragging seen near the vicinity of a rotating superconductor...
In their initial publication [1], they attempted to use the apparent increase in the charge to mass ratio of electrons within a superconductor measured by tate et al. [2] to answer the non-classical frame dragging phenomenon (which is if I remember, >18 orders of magnitude stronger than classically predicted by GR). I coudn't understand where and how they derived many of the equations so I simply ignored their initial paper for the theoretical aspects on [1].
The canterbury group at New Zealand is still the only group in the world to attempt replicating the effect and they concluded that the effect does not exist [3]. But they still measured an anomalous torque within the vicinity of the cryogenically cooled rotating superconductor. Tajmar et al. [4-7] continued to refine their experiment by using a similar measurement technique as Graham with a higher sensitivity setup to detect the effect and similarly measured an induced rotation and anomalous torque. They've taken into account of many environmental factors and concluded even after Graham's results that the effect is real (specifically see [7])...
Superconductors surely have some interesting features to themselves (those obvious phenomenons, I won't explain...) such as the Tao Ball phenomenon where superconducting particles form a millimeter scale sphere under strong electric field [8].
So the discussion that I would like to bring up is, does anybody have a thought for these phenomenon ? Does everybody think that it's simply measurement error ? I understand that condensed matter physics and theoretical understanding of high temperature superconductors are still undergoing enormous research. But I wanted to discuss the implication and significance of this effect to the understanding of the universe (if the effect is indeed real and can be verified by more than just two groups). Hmm... I hope I am asking the question I hoped to ask...
The reference links are provided below (mostly from the arXiv site), some I couldn't find electronic reprints, just hard copy from journals.
[1]http://arxiv.org/abs/gr-qc/0603033
[2]Tate, J., Cabrera, B., Felch, S.B., Anderson, J.T., "Determination of the Cooper-
Pair Mass in Niobium" Phys. Rev. B 42(13), 7885-7893 (1990).
[3]http://www2.phys.canterbury.ac.nz/~physrin/papers/SuperFrameDragging2007.pdf
[4]http://arxiv.org/abs/gr-qc/0610015
[5]http://arxiv.org/abs/gr-qc/0610015
[6]http://arxiv.org/abs/0806.2271
[7]http://arxiv.org/abs/0707.3806
[8][8] R. Tao, X. Xu, and E. Amr, “MgB2 superconducting particles in a strong electric field”, Physica C, V398, N3-4, 78—84, 2003.
Note: [3] was published and can be found on the Elseveir website but you must pay. So I'm just providing you the link to their group website.
This is my first post and I am guessing I should post my question here at the astrophysics section so I'm doing so (admin, if you think the topic should belong somewhere else, please move it).
My question is with regards to the continued research conducted by Tajmar et al [1,4-7]. To answer the apparent, what seems to be an amplified effect of classical frame dragging seen near the vicinity of a rotating superconductor...
In their initial publication [1], they attempted to use the apparent increase in the charge to mass ratio of electrons within a superconductor measured by tate et al. [2] to answer the non-classical frame dragging phenomenon (which is if I remember, >18 orders of magnitude stronger than classically predicted by GR). I coudn't understand where and how they derived many of the equations so I simply ignored their initial paper for the theoretical aspects on [1].
The canterbury group at New Zealand is still the only group in the world to attempt replicating the effect and they concluded that the effect does not exist [3]. But they still measured an anomalous torque within the vicinity of the cryogenically cooled rotating superconductor. Tajmar et al. [4-7] continued to refine their experiment by using a similar measurement technique as Graham with a higher sensitivity setup to detect the effect and similarly measured an induced rotation and anomalous torque. They've taken into account of many environmental factors and concluded even after Graham's results that the effect is real (specifically see [7])...
Superconductors surely have some interesting features to themselves (those obvious phenomenons, I won't explain...) such as the Tao Ball phenomenon where superconducting particles form a millimeter scale sphere under strong electric field [8].
So the discussion that I would like to bring up is, does anybody have a thought for these phenomenon ? Does everybody think that it's simply measurement error ? I understand that condensed matter physics and theoretical understanding of high temperature superconductors are still undergoing enormous research. But I wanted to discuss the implication and significance of this effect to the understanding of the universe (if the effect is indeed real and can be verified by more than just two groups). Hmm... I hope I am asking the question I hoped to ask...
The reference links are provided below (mostly from the arXiv site), some I couldn't find electronic reprints, just hard copy from journals.
[1]http://arxiv.org/abs/gr-qc/0603033
[2]Tate, J., Cabrera, B., Felch, S.B., Anderson, J.T., "Determination of the Cooper-
Pair Mass in Niobium" Phys. Rev. B 42(13), 7885-7893 (1990).
[3]http://www2.phys.canterbury.ac.nz/~physrin/papers/SuperFrameDragging2007.pdf
[4]http://arxiv.org/abs/gr-qc/0610015
[5]http://arxiv.org/abs/gr-qc/0610015
[6]http://arxiv.org/abs/0806.2271
[7]http://arxiv.org/abs/0707.3806
[8][8] R. Tao, X. Xu, and E. Amr, “MgB2 superconducting particles in a strong electric field”, Physica C, V398, N3-4, 78—84, 2003.
Note: [3] was published and can be found on the Elseveir website but you must pay. So I'm just providing you the link to their group website.