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| bio | website | jfitzsimons.org |
|---|---|---|
| location | Singapore, Singapore | |
| age | 31 | |
| visits | member for | 2 years, 7 months |
| seen | 2 days ago | |
| stats | profile views | 470 |
I have just moved to the Center for Quantum Technologies in Singapore, after spending the last 3 years as a Merton College JRF in Theoretical Physics and a Senior Research Fellow in Oxford University Department of Materials. My research focuses largely on theoretical aspects of quantum information processing. In particular I am interested in spin networks, measurement based computation, cryptography and computational complexity.
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Oct 1 |
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Which symmetric pure qudit states can be reached within local operations? @NieldeBeaudrap: Yes. In fact the basis of product states is exactly the reason why there cannot be some observable which has a different expectation for some entangled state on this space if it's expectation value is constant across all product states. |
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Oct 1 |
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An entropy of the Wigner function Welcome to TP.SE, Earl. Good to see you here. |
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Oct 1 |
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Which symmetric pure qudit states can be reached within local operations? Welcome to TP.SE! I wasn't aware of that paper, but it seems an interesting observation, and looks like it might generalize beyond qubits. |
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Sep 30 |
answered | Which symmetric pure qudit states can be reached within local operations? |
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Sep 29 |
awarded | Nice Answer |
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Sep 29 |
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What is the use of a Universal-NOT gate? The first answer you give is exactly the justification they give in the paper, but it's not a reason why you would actually want to be able to do it. As regards the second, you don't actually need a universal NOT for that, you simply need an operator that anti-commutes with the Hamiltonian, and there are potentially far better time reversal techniques (i.e. WaHuHa etc.). The partial transpose test does seem to be one reason to want it though. |
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Sep 29 |
asked | What is the use of a Universal-NOT gate? |
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Sep 26 |
answered | Information Retrieval |
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Sep 25 |
answered | The Role of Rigor |
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Sep 25 |
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The Role of Rigor @UGPhysics: I really don't see how it would get meaningful answers there. He is asking questions that are probably best answerable by either physicists or historians of science. |
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Sep 24 |
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The Role of Rigor From my perspective, at least, this seems to be an interesting question phrased in a way that can have reasonably objective answers, so I don't see why it should be closed. |
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Sep 24 |
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Post-doc advice for a low publication grad student @RobertFilter: It was 5 years ago for me, so not that recent, but the memories are still fresh. |
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Sep 24 |
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Post-doc advice for a low publication grad student @Robert: There are people on here with more experience than me, so there are probably more authoritative answers out there. |
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Sep 24 |
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Models of neutrinos consistent with OPERA's results @LubošMotl: I'm afraid I haven't had a chance to really dig into the two papers yet. It seemed like it might be ok by a rough back of the envelope calculation, given how big the error bars on previous results are, but I certainly wouldn't swear by it. |
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Sep 24 |
accepted | Models of neutrinos consistent with OPERA's results |
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Sep 24 |
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Models of neutrinos consistent with OPERA's results Yes, sorry, I should have been clearer on that. I just thought it was interesting in the context of the energy dependence loophole. |
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Sep 23 |
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Models of neutrinos consistent with OPERA's results Thanks Lubos for the detailed answer. For what it's worth, I've also just come across arXiv:0805.0253 by John Ellis and others which examines energy dependent velocities, and doesn't seem to be entirely incompatible with the current results. Thanks for a great answer, and welcome to the site. |
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Sep 23 |
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Models of neutrinos consistent with OPERA's results @Michael: What in particular? The superluminal bit? Yep, it's crazy, and everyone seems to be rightly skeptical, but who knows? It's unlikely we will know for sure until other experiments either replicate or fail to replicate the results. Even the OPERA team seems skeptical of their own results. |
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Sep 23 |
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Models of neutrinos consistent with OPERA's results @Slaviks: No. I mean that the bounds are further away from $c$ for increasing energy, and this could be explained by a monotonic function, which seems more natural than a non-monotonic one. I guess you are refering to the 3GeV data point, but here the error bars are loose, so it could easily be below the 17GeV velocity while still being within the error bars. But, frankly I'd be interested in any models which fit all 4 points relatively well. |
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Sep 23 |
asked | Models of neutrinos consistent with OPERA's results |
