Recent comments from SciRate

Connor Paddock Jan 27 2023 03:24 UTC

Check out our [video abstract][1]!

[1]: https://www.youtube.com/watch?v=Rli8yM_KkNM

Korbinian Kottmann Jan 16 2023 08:26 UTC

What is the number of qubits for the numerical simulations? Reads like it is one fixed number but certainly that cannot be the case?

Seok-Hyung Lee Jan 09 2023 11:08 UTC

Thank you for your kind and detailed reply!

Jahan Claes Jan 08 2023 17:12 UTC

I think this is a fair question! We were guided to our construction by considering the XZZX cluster state, but that doesn't mean this is the only way to understand our construction.

Certainly, in the case of the 4-star construction, there *are* no qubits that correspond to the RHG/XZZX cluster stat

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Seok-Hyung Lee Jan 08 2023 07:17 UTC

Very interesting work! May I ask you a small question? I think the idea to confine erasure errors caused by failed fusions on 2D planes also can be applied to the normal Raussendorf's lattice. In other words, we can freely choose the fusion basis (two distinguishable Bell states) for each fusion so

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Alexander Belov Jan 06 2023 16:02 UTC

Thanks for the reference! This seems to be exactly the same result, but obtained in a slightly different manner.

Minki Hhan Jan 06 2023 05:00 UTC

Very interesting result! A quick question on the unitary permutation inversion problem. I think this unitary permutation oracle was studied under the name of the in-place permutation, and a similar result was shown in https://arxiv.org/abs/1510.06750, Section 3.2. Is there any difference between the

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Mario Szegedy Jan 05 2023 14:05 UTC

I thank for the comments of Jan Eisert, whose survey on the area law btw. has been a very illuminating work for me. Let me address the points made:

1. Indeed, the two papers look at different NPO (NP-Optimization) problems. To understand the NPO landscape, here is somewhat of a background. The t

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Seok Hyung Lie Jan 05 2023 06:20 UTC

Nice work. I am not well versed with the literature in the field so I am a bit confused; Is the result that a unital qubit channel can be expressed as the average of 4 unitary channels (Theorem 3.1) new here? I think one can derive it from Corollary 1.3 of [arXiv:1802.01337][1] and that the set of

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Jens Eisert Jan 04 2023 14:18 UTC

We are excited to see that Mario Szegedy as a leading expert on the PCP theorem has looked at the problem that we lay out in our work arXiv:2212.08678 and has suggested an alternative proof of a similar statement as we present it in our work based on the PCP theorem. With this note, we would kindly

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Mankei Tsang Dec 30 2022 04:51 UTC

Apologies for a bit of shameless self-promotion, but I wrote a paper on the connection between the Loschmidt echo and quantum metrology back in 2013: https://doi.org/10.1103/PhysRevA.88.021801, which is a bit earlier than a lot of the papers cited here, e.g., Macri, Smerzi, Pezze, "Loschmidt echo fo

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Craig Gidney Dec 28 2022 15:33 UTC

Minor but annoying errata: the future work section has the placeholder text "[reference to jupyter]" instead of an actual reference to the notebook.

HIGS Dec 23 2022 05:23 UTC

The [web of science journal indexing][1] database indexes each article in journals. HIGS has a complete list of [Web of Science Journal list][2] . Get connected with our team now and download the list. Our team also provides so many free add-ons. [For More Information][3]

[1]: http://higssof

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Josu Etxezarreta Martinez Dec 13 2022 09:25 UTC

I leave some references on Time-varying quantum channels which I missed in the article (I know I am the author of those, but there is little literature on the topic):

https://www.nature.com/articles/s41534-021-00448-5

https://journals.aps.org/pra/abstract/10.1103/PhysRevA.105.012432

https:/

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Blake Stacey Dec 08 2022 18:54 UTC

You write "the linearity of $H_{i,j}$" (penultimate paragraph). I think that should read "the existence of $H_{i,j}$"; the thing that is linear is the map. But a map from density matrices to probabilities is linear if and only if it can be written as the trace of $H \rho$ for some $H$. If your main

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Thomas D. Galley Dec 08 2022 08:39 UTC

We have written a response which can be found here https://scirate.com/arxiv/2212.03629

Simon Apers Dec 08 2022 08:08 UTC

Yesterday's Quanta magazine article on this: [link][1].

[1]: http://www.quantamagazine.org/after-a-classical-clobbering-a-quantum-advantage-remains-20221207/

Evan Peters Dec 02 2022 19:38 UTC

Note that Problem 1 of Appendix C is equivalent to the construction of a perfect [Golomb ruler][1] of length $m$. This problem admits no solution for $m \geq 5$.

We discuss some implications of this for the Fourier spectra of quantum models in ([2209:05523][2]).

[1]: https://en.wikipedia.

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James Wootton Nov 24 2022 08:46 UTC

In Fig. 4, it looks to me like the three logical qubits could be described by the following pairs of logical $Z$ and $X$:

* $Z_1 Z_2$ and $X_1 X_5 X_9$;
* $Z_3 Z_4$ and $X_1 X_3$;
* $Z_7 Z_8$ and $X_7 X_9$.

From these it seems that the code is in fact distance 2, rather than distance 3.

Am I miss

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Zhenghao Li Nov 18 2022 16:57 UTC

Ah I see. Thanks for your reply!

Lim Youngrong Nov 16 2022 20:32 UTC

Thank you for your question. Because the error of our scheme is larger than what we need in the hardness conjecture of that paper, our result does not contradict the conjecture.
Please refer to AA's original boson sampling paper, where a similar thing happened for the permanent and Gurvits's algorit

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Zhenghao Li Nov 15 2022 18:16 UTC

Hi, amazing work! I was wondering if your results would affect the structure of proof in [https://www.science.org/doi/epdf/10.1126/sciadv.abi7894][1], which is based on the conjecture that |Haf|^2 is #P-hard to approximate to within *additive* error (Conjecture 2 in the paper)? Thanks!

[1]: h

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Lorenzo Leone Nov 11 2022 06:13 UTC

Amazing work! Look forward to reading it in more detail!

Patryk Lipka-Bartosik Nov 03 2022 07:53 UTC

Thanks for the nice question. In this framework, in the simplest case, we have two systems (the main system and the heat bath) coupled by an energy-conserving interaction. Therefore, any change in the energy of the system
is equivalent to the same (with a minus sign) change on the bath (therefore

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MariusK Nov 02 2022 12:47 UTC

I really like your axiomatic formalization!

One suggestion, though:
I would rename "efficiency" to "faithfulness".

Seok Hyung Lie Nov 02 2022 05:45 UTC

Thanks for the reply. I have a small question content-wise. Is there no distinction between work and heat in this framework? It seems like all the energy influx into a system is counted as 'heat', but I think somehow work can be exchanged too between systems with different temperatures through a ene

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Patryk Lipka-Bartosik Nov 01 2022 19:39 UTC

Thanks for the comment. You are right. The second statement about heat flows should be just as you wrote, i.e: "heat will flow from the environment". The right statement is captured by Eq. (5).

Thanks for mentioning the typos. We plan to update the arXiv version soon; We'll get rid of them :)

Aram Harrow Nov 01 2022 18:06 UTC

Classic work establishing, among other things, equivalence between establishing high entanglement fidelity and low diamond-norm error. However, the arxiv version has an incorrect proof of this fact (Thm 1 in section V.A); see the IEEE IT version for the correct proof.

Seok Hyung Lie Nov 01 2022 07:21 UTC

Nice work. I am still reading the paper but I think "Heat will always flow towards the environment " and "the environment will always absorb
heat" on the first page mean the same thing. It seems like the second sentence should say that the heat will flow from the environment as it is hotter than $\r

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Elizabeth Crosson Oct 28 2022 14:28 UTC

The proof that the stoquastic local Hamiltonian problem is in AM also applies to stoquastic Hamiltonians that are sparse, but non-local. On [page 5][1]:

"Moreover, we will prove that evaluation of the largest eigenvalue of any n-qubit non-negative matrix whose matrix elements are efficiently co

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Chinmay Nirkhe Oct 28 2022 11:17 UTC

I see. We are no experts in the technicalities here so we will correct the section here accordingly. I believe MA is correct since the Hamiltonian corresponding to a graph is frustration-free. But we will need to clarify this.

All we were trying to say (and the gist this holds) that the algorithm

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Yupan Liu Oct 28 2022 04:19 UTC

Thanks for this interesting result, but I am confused about the discussion regarding stochastic Hamiltonians (on Page 7):
> The problem of calculating the ground energy of stoquastic local Hamiltonians was shown to be contained in MA by Bravyi, Divincenzo, Oliveira, and Terhal [BDOT08].

As far as

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Yoshifumi Nakata Oct 28 2022 00:08 UTC

We updated our paper. In the new version (ver. 2), we removed an unnecessary assumption, which rarely holds in general as pointed out, and further improved Theorem 1. We mentioned the comparison of the performance of our decoder with previous ones as an interesting future problem.

Seok Hyung Lie Oct 25 2022 17:58 UTC

Nice work on superchannels. However, I have a simple question about the motivation of studying QSCs. Superchannels are naturally characterized by the requirement that they should map bipartite quantum channels to bipartite quantum channels even if they act on one party of the channel. On the other

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MariusK Oct 25 2022 16:11 UTC

It might be worth saying more about the implementability of your encoding $R_f$.
Your Figure 1 (b) seems to suggest that one needs over 50 orders of magnitude of precision.
You mention that this leads to numerical instabilities.
However, I am more worried about experimental implementations in act

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Wojciech Kryszak Oct 21 2022 20:37 UTC

It seems to be a nice clash between you and Nicolas - a lot to think about, thank you (both)!

> Wouldn’t we be more free if we can determine our next decisions
> based on how we are now, rather than letting them at the mercy of
> randomness?

My nearest next decision is just almost now so I

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MJKastoryano Oct 19 2022 10:28 UTC

Thanks for the clarifications, and for the nice paper!

Chris (Jielun) Chen Oct 18 2022 15:02 UTC

Hi, thanks a lot for the reply! Our paper’s results mainly differ from them as follows:

- In the two papers you mentioned, the authors consider the *exact* tensor contraction of the *approximate* QFT (AQFT) on product inputs and outputs. Specifically, they are simulating $\langle x| C |y\rangle$,

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MJKastoryano Oct 18 2022 10:34 UTC

How do your results relate to, [arXiv:quant-ph/0611156] and [Phys. Rev. A 76,
042321 (2007)]? On the surface, the conclusions look quite similar.

Johannes Bausch Oct 18 2022 09:13 UTC

Interesting paper! One point: I wouldn't say that current quantum NNs don't have inductive biases; my paper on QRNNs (https://arxiv.org/abs/2006.14619) has a circuit designed to mimick latent state read and write operations; as well as many circuits used in the context of many-body Hamiltonians feat

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Yoshifumi Nakata Oct 15 2022 09:45 UTC

Thanks for letting us know a relevant paper. We have not compared our bound with yours. We will have a closer look and write you back.

Jon Tyson Oct 15 2022 09:01 UTC

Have you compared your new bound to those of equation (153) of https://arxiv.org/abs/0907.3386? Note that this is NOT the Petz map, and furthermore the gamma quantities do not involve anything at all similar to a petz map.

Yoshifumi Nakata Oct 15 2022 08:39 UTC

Thank you for pointing it out. You are right, the basis $F_{\diamond}$ satisfying our condition rarely exists unless $E$ and $F$ are already MUBs.

We will update the paper soon, but we would like to mention here that our main message is still valid: $\Delta_q$ is bounded by $\Delta_{cl, E}$, $\De

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Jon Tyson Oct 15 2022 07:43 UTC

To put this another way, choosing the computational basis to be the $F$-basis , equation 12 and the one directly above it say that the vectors in $F_\Diamond$ are formed by rescaling each coordinate of each $E$ -vector (by a positive real number multiple) to have magnitude $d^{1/2}$.

However the

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Jon Tyson Oct 14 2022 15:11 UTC

Unfortunately, there a bug in equation (12), which overdetermines the phases of the coordinates of the mutually unbiased basis F_diamond in the F-basis.

Since generally there is no MUB satisfying all these phase conditions, the decoder of Theorem 1 does not exist for most bases E and F in dimension

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Pasi Lähteenmäki Oct 14 2022 10:05 UTC

Contrary to the author, I certainly don't know that I or anyone else has free will. I just know that I exist as I keep experiencing things. I can't even imagine how free will would work. One would first have to define free will in a coherent manner to have a meaningful discussion about it. What exac

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Blake Stacey Oct 13 2022 13:24 UTC

The basic suggestion of "maybe we can combine economics with gauge theory" is at least as old as a 1994 essay by Lane Hughston, better known to physicists for his work on [density-matrix decompositions](https://en.wikipedia.org/wiki/Schr%C3%B6dinger%E2%80%93HJW_theorem):

L. P. Hughston (1994), "S

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Hakop Pashayan Oct 12 2022 12:28 UTC

Hi Robert

I fully agree :). Indeed high weigh Paulis are an "expensive" observable for classical shadows in general as they have exponential sample complexity in all three depth regimes. Nevertheless, the sample complexity can be orders of magnitude different depending on the choice of depth used

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Jalan Ziyad Oct 11 2022 22:10 UTC

Hi there is an error on Figure 1. Your logical Z doesn't commute with one of the stabilizers.

Hsin-Yuan Huang Oct 11 2022 14:58 UTC

Hi Hakop,

Thank you for the prompt reply! That makes the advancement much clearer!

To summarize, for the computational task (1), the efficiency in your work refers to the fact that one can compute the estimated value of any linear combination of $\mathrm{poly}(n)$ general Paulis from classical sha

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