Felix Leditzky 🏳️‍🌈🏳️‍⚧️

Today my group put out 5 new papers in time for the QIP deadline next week! With 221 (!) other papers posted to arXiv.org/quant-ph today, it might be a good idea to try to increase their visibility. I'll mention them sorted alphabetically by title (and might add little blurbs about each later) 🧵

We acknowledge that no one has the bandwidth for this, but if it helps: -It’s ‘sleight of hand’ -It’s ‘bated breath’ -It’s ‘lo and behold’ -It's 'buck naked' -It’s ‘brass tacks’ -It’s ‘free rein’ -It’s ‘toe the line'

TIL that anyon is literally to mean "any-on", as in anything goes.

"If an expert prompts a result, they take up the mantle of responsibility I describe above [of explaining what you did, what is new vs. well-known, and nurturing the literature]. OpenAI not only refuses to take their responsibility, but they prevent their own customers from doing so." 🎯💯👏

You may finally rest easy at night since SICs exist in all dimensions! github.com/marozols/SIC... SICs are d² unit vectors in d complex dimensions with pairwise equal inner products. Their existences in all dimensions d was conjectured by Zauner in 1999. en.wikipedia.org/wiki/SIC-POVM

Where is the understanding in any of this?

Congratulations to this year's winner of the Physics Nobel Prize!

What is the IceCube neutrino observatory? Neutrinos are elusive particles that rarely interact, but can create flashes of light when they do. Most neutrino detectors are giant water tanks surrounded by light detectors. IceCube is kilometer-long strings of detectors embedded in the Antarctic ice.

arXiv has updated our policy on rate limiting for all submitters. This update was made to fairly distribute moderator time & support the arXiv community of staff, volunteers, readers & authors. Please read our announcement to learn more: https://blog.arxiv.org/2026/10/01/updated-rate-limit-policy/

We analyze optimal data hiding schemes based on multipartite Werner states under PPT measurements, using the representation-theoretic framework of mixed Schur-Weyl duality. scirate.com/arxiv/2609.4...

We investigate constructions of exact unitary designs under symmetry constraints that reflect physical limitations in quantum devices. scirate.com/arxiv/2609.4...

We study the compatibility of measurements, quantum channels and quantum instruments using techniques from operator space theory. scirate.com/arxiv/2609.4...

We recast the sample complexity of k-copy quantum state discrimination as a quantum mixing time problem that becomes fully classical under suitable (and natural) symmetries, with applications to e.g. learning phase states and hypergraph states. scirate.com/arxiv/2609.4...

We use representation theory to understand IID depolarizing channels as Gaussian channels in a suitable limit, which yields a substantial improvement on the best lower bound on the quantum capacity threshold of the depolarizing channel. scirate.com/arxiv/2609.3...

🐻↘️🦅

Shame on @qipconference.bsky.social for using X/twitter. You give our community a bad name.

A new risk for mathematicians: a colleague reports that immediately after they posted an abstract of their upcoming talk online, a student elsewhere used AI to derive proofs of the stated results and then posted it on the arxiv. My colleague hadn't posted to arxiv yet. Scummy. Watch out.

Good morning from @perimeterinstitute.bsky.social ! ☀️

New work "High quantum local differential privacy breaks entanglement" led by my student Sujeet Bhalerao and postdoc Theshani Nuradha! We study the interplay of local differential privacy and entanglement, and implications for learning theory in the private setting. scirate.com/arxiv/2609.1...

One could try to explain Navier-Stokes drama via hypothesis that Levent or Tristan did not properly turn off data-sharing in ChatGPT. It is not enough to turn off "Improve the model for everyone" in Data controls settings, you need to submit it via "Privacy center". 1/3

Caution should be applied when using LLMs in your research. This story is wild.

arXiv submission statistics for the quant-ph channel for the last 5 years, 2 years, 6 months.

Great way to honor Dolly Parton: donate.imaginationlibrary.com

Awful news

AI sloppers, they ain't scholars, just faking it Forcing youth away from the truth, they ain't making it The kids of today should defend themselves against GPT Emptying minds with empty lies gotta make you laugh Tech-bro vendors buying true defenders of the math

Is anyone else bothered by the fact that \overset{x}{y} puts x over y and not the other way round? I always think this out loud as "overset x with y", only to find my latex garbled.