Dave Bacon
@dabacon.tachyon.institute
Theoretical ski bum. Former pseudo professor. Quantum bridge builder. Will math for food.
mastodon: @dabacon@tachyon.channel
https://dabacon.org
mastodon: @dabacon@tachyon.channel
https://dabacon.org
Pinned
Dave Bacon
@dabacon.tachyon.institute
· Apr 25
Much Madness is divinest Sense -
To a discerning Eye -
Much Sense - the starkest Madness -
’Tis the Majority
In this, as all, prevail -
Assent - and you are sane -
Demur - you’re straightway dangerous -
And handled with a Chain -
—Emily Dickinson
To a discerning Eye -
Much Sense - the starkest Madness -
’Tis the Majority
In this, as all, prevail -
Assent - and you are sane -
Demur - you’re straightway dangerous -
And handled with a Chain -
—Emily Dickinson
Reposted by Dave Bacon
The list of accepted papers for #QIP2026 is now online at qip2026.lu.lv/programme/ac...
Accepted papers
qip2026.lu.lv
November 11, 2025 at 1:28 PM
The list of accepted papers for #QIP2026 is now online at qip2026.lu.lv/programme/ac...
“but those pages cannot save me, perhaps because what is good belongs to no one, not even to him, but rather to the language and to tradition” - Borges
November 9, 2025 at 4:31 AM
“but those pages cannot save me, perhaps because what is good belongs to no one, not even to him, but rather to the language and to tradition” - Borges
Hopefullly they also include test of space awards.
Computational Complexity Conference launches its first test of time award. Nominations due by March 2.
computationalcomplex...
computationalcomplex...
November 9, 2025 at 4:28 AM
Hopefullly they also include test of space awards.
Down with the Pauli group stabilizer hegemony scirate.com/arxiv/2511.0...
Clifford Hierarchy Stabilizer Codes: Transversal Non-Clifford Gates and Magic
A fundamental problem in fault-tolerant quantum computation is the tradeoff between universality and dimensionality, exemplified by the the Bravyi-König bound for $n$-dimensional topological stabilize...
scirate.com
November 6, 2025 at 2:32 PM
Down with the Pauli group stabilizer hegemony scirate.com/arxiv/2511.0...
Reposted by Dave Bacon
Department of Physics at UIUC is looking for an Assistant Professor in Theoretical Quantum Information Science, including, but not limited to, quantum error correction, quantum optics, quantum algorithms, and AMO physics.
Application deadline: Dec 1
illinois.csod.com/ux/ats/caree...
Application deadline: Dec 1
illinois.csod.com/ux/ats/caree...
Grainger Engineering: Assistant Professor in Theoretical QIS - Department of Physics
Duties & Responsibilities
illinois.csod.com
November 5, 2025 at 1:14 PM
Department of Physics at UIUC is looking for an Assistant Professor in Theoretical Quantum Information Science, including, but not limited to, quantum error correction, quantum optics, quantum algorithms, and AMO physics.
Application deadline: Dec 1
illinois.csod.com/ux/ats/caree...
Application deadline: Dec 1
illinois.csod.com/ux/ats/caree...
Reposted by Dave Bacon
To celebrate 2025 John Bell Day, which marks the work of the great Northern Irish quantum physicist, do check out this legendary feature he wrote for Physics World just before he died in 1990. ⚛️🧪🔭
physicsworld.com/a/against-me...
physicsworld.com/a/against-me...
Against 'measurement': John Bell on our continuing struggles with quantum mechanics – Physics World
Uncertainty over terms such as ‘apparatus’ is still rife in serious discussions of quantum mechanics, over 60 years after its conception, says John Bell
physicsworld.com
November 4, 2025 at 12:34 PM
To celebrate 2025 John Bell Day, which marks the work of the great Northern Irish quantum physicist, do check out this legendary feature he wrote for Physics World just before he died in 1990. ⚛️🧪🔭
physicsworld.com/a/against-me...
physicsworld.com/a/against-me...
Reposted by Dave Bacon
Congratulations to Venkat Guruswami, new director of the Simons Institute for the Theory of Computing (@simonsinstitute.bsky.social)! And congrats to us, the Theoretical CS community, for having someone as good, dedicated, and wonderful as him at the helm of a place so important to us! #TCSSky
October 30, 2025 at 8:18 PM
Congratulations to Venkat Guruswami, new director of the Simons Institute for the Theory of Computing (@simonsinstitute.bsky.social)! And congrats to us, the Theoretical CS community, for having someone as good, dedicated, and wonderful as him at the helm of a place so important to us! #TCSSky
Reposted by Dave Bacon
The Frontiers of Programmable Quantum Dynamics: Advances and Applications
conference has concluded today, and recorded talks are now available to watch at
buff.ly/2lD7WTC and buff.ly/AXJjS4e
Watch more talks from the associated program online at buff.ly/QHE8YtH
🧪
conference has concluded today, and recorded talks are now available to watch at
buff.ly/2lD7WTC and buff.ly/AXJjS4e
Watch more talks from the associated program online at buff.ly/QHE8YtH
🧪
KITP Conference: Frontiers of Programmable Quantum Dynamics: Advances and Applications
buff.ly
October 31, 2025 at 1:16 AM
The Frontiers of Programmable Quantum Dynamics: Advances and Applications
conference has concluded today, and recorded talks are now available to watch at
buff.ly/2lD7WTC and buff.ly/AXJjS4e
Watch more talks from the associated program online at buff.ly/QHE8YtH
🧪
conference has concluded today, and recorded talks are now available to watch at
buff.ly/2lD7WTC and buff.ly/AXJjS4e
Watch more talks from the associated program online at buff.ly/QHE8YtH
🧪
Reposted by Dave Bacon
It’s really too bad that my sub-field of quantum foundations research doesn’t have any Halloween-related or spooky aspects, no way that anyone could ever use the season to drum up any... any fake-quoted, overdramatic…
Oh.
Oh dear.
molotovsunsets.substack.com/p/the-univer...
Oh.
Oh dear.
molotovsunsets.substack.com/p/the-univer...
The Universe Knows How You Die
Retrocausality and the Backward Reach of Time
molotovsunsets.substack.com
October 30, 2025 at 4:10 PM
It’s really too bad that my sub-field of quantum foundations research doesn’t have any Halloween-related or spooky aspects, no way that anyone could ever use the season to drum up any... any fake-quoted, overdramatic…
Oh.
Oh dear.
molotovsunsets.substack.com/p/the-univer...
Oh.
Oh dear.
molotovsunsets.substack.com/p/the-univer...
Reposted by Dave Bacon
Another day, another arxiv paper claiming that classical gravity can produce entanglement. Last week's Nature paper continues to cause confusion. But classical fields can't create entanglement *even if* they directly couple two masses. Comment added at superposer.substack.com/p/no-classic...
October 28, 2025 at 3:24 PM
Another day, another arxiv paper claiming that classical gravity can produce entanglement. Last week's Nature paper continues to cause confusion. But classical fields can't create entanglement *even if* they directly couple two masses. Comment added at superposer.substack.com/p/no-classic...
Academia giving up self governance makes me so sad. I remember when Caltech used to have faculty actually interview undergrad applicants, which I think led to more outliers and quirkiness. Efficiency breeds homogeneity.
The University of Chicago "does not list a single faculty member on its board... composed predominantly of CEOs and CFOs from private-equity or venture-capital firms, lawyers, and a founder of a women’s professional-football group." www.chronicle.com/article/rese...
Research Is the U. of Chicago’s Lifeblood. Its Board Is Killing It.
A great university could be reduced to a shell of its former self.
www.chronicle.com
October 28, 2025 at 5:17 PM
Academia giving up self governance makes me so sad. I remember when Caltech used to have faculty actually interview undergrad applicants, which I think led to more outliers and quirkiness. Efficiency breeds homogeneity.
Reposted by Dave Bacon
43 years ago today, readers the world over opened their newspapers and gazed upon cow tools for the first time. happy birthday cow tools. you look great.
October 28, 2025 at 12:23 PM
43 years ago today, readers the world over opened their newspapers and gazed upon cow tools for the first time. happy birthday cow tools. you look great.
Reposted by Dave Bacon
yeah, i read theory
July 26, 2025 at 1:11 PM
yeah, i read theory
This story reminded me of the magazine Quantum, a godsend for me, rural high school hick who loved math and physics. It turns out the issues are all online www.nsta.org/quantum-maga...
October 28, 2025 at 3:44 AM
This story reminded me of the magazine Quantum, a godsend for me, rural high school hick who loved math and physics. It turns out the issues are all online www.nsta.org/quantum-maga...
Reposted by Dave Bacon
📣 𝗨𝗽𝗰𝗼𝗺𝗶𝗻𝗴 𝗧𝗮𝗹𝗸
On 𝗧𝘂𝗲𝘀𝗱𝗮𝘆, 𝗢𝗰𝘁𝗼𝗯𝗲𝗿 𝟮𝟴, 𝟮𝟬𝟮𝟱 (𝟭𝟲:𝟬𝟬 𝗔𝗺𝘀𝘁𝗲𝗿𝗱𝗮𝗺 𝘁𝗶𝗺𝗲), 𝗔𝗹𝗲𝘅 𝗠𝗲𝗶𝗯𝘂𝗿𝗴 will give a talk on his paper “𝗔 𝗙𝗼𝗿𝗺𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻 𝗼𝗳 𝘁𝗵𝗲 𝗚𝗲𝗻𝗲𝗿𝗮𝗹𝗶𝘇𝗲𝗱 𝗤𝘂𝗮𝗻𝘁𝘂𝗺 𝗦𝘁𝗲𝗶𝗻’𝘀 𝗟𝗲𝗺𝗺𝗮 𝗶𝗻 𝗟𝗲𝗮𝗻” (buff.ly/TnHFhZE) at the Lean Seminar in Amsterdam.
🔗 Zoom link: buff.ly/w7DqsRC
🆔 Meeting ID: 610 4772 0375
On 𝗧𝘂𝗲𝘀𝗱𝗮𝘆, 𝗢𝗰𝘁𝗼𝗯𝗲𝗿 𝟮𝟴, 𝟮𝟬𝟮𝟱 (𝟭𝟲:𝟬𝟬 𝗔𝗺𝘀𝘁𝗲𝗿𝗱𝗮𝗺 𝘁𝗶𝗺𝗲), 𝗔𝗹𝗲𝘅 𝗠𝗲𝗶𝗯𝘂𝗿𝗴 will give a talk on his paper “𝗔 𝗙𝗼𝗿𝗺𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻 𝗼𝗳 𝘁𝗵𝗲 𝗚𝗲𝗻𝗲𝗿𝗮𝗹𝗶𝘇𝗲𝗱 𝗤𝘂𝗮𝗻𝘁𝘂𝗺 𝗦𝘁𝗲𝗶𝗻’𝘀 𝗟𝗲𝗺𝗺𝗮 𝗶𝗻 𝗟𝗲𝗮𝗻” (buff.ly/TnHFhZE) at the Lean Seminar in Amsterdam.
🔗 Zoom link: buff.ly/w7DqsRC
🆔 Meeting ID: 610 4772 0375
October 24, 2025 at 6:09 PM
📣 𝗨𝗽𝗰𝗼𝗺𝗶𝗻𝗴 𝗧𝗮𝗹𝗸
On 𝗧𝘂𝗲𝘀𝗱𝗮𝘆, 𝗢𝗰𝘁𝗼𝗯𝗲𝗿 𝟮𝟴, 𝟮𝟬𝟮𝟱 (𝟭𝟲:𝟬𝟬 𝗔𝗺𝘀𝘁𝗲𝗿𝗱𝗮𝗺 𝘁𝗶𝗺𝗲), 𝗔𝗹𝗲𝘅 𝗠𝗲𝗶𝗯𝘂𝗿𝗴 will give a talk on his paper “𝗔 𝗙𝗼𝗿𝗺𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻 𝗼𝗳 𝘁𝗵𝗲 𝗚𝗲𝗻𝗲𝗿𝗮𝗹𝗶𝘇𝗲𝗱 𝗤𝘂𝗮𝗻𝘁𝘂𝗺 𝗦𝘁𝗲𝗶𝗻’𝘀 𝗟𝗲𝗺𝗺𝗮 𝗶𝗻 𝗟𝗲𝗮𝗻” (buff.ly/TnHFhZE) at the Lean Seminar in Amsterdam.
🔗 Zoom link: buff.ly/w7DqsRC
🆔 Meeting ID: 610 4772 0375
On 𝗧𝘂𝗲𝘀𝗱𝗮𝘆, 𝗢𝗰𝘁𝗼𝗯𝗲𝗿 𝟮𝟴, 𝟮𝟬𝟮𝟱 (𝟭𝟲:𝟬𝟬 𝗔𝗺𝘀𝘁𝗲𝗿𝗱𝗮𝗺 𝘁𝗶𝗺𝗲), 𝗔𝗹𝗲𝘅 𝗠𝗲𝗶𝗯𝘂𝗿𝗴 will give a talk on his paper “𝗔 𝗙𝗼𝗿𝗺𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻 𝗼𝗳 𝘁𝗵𝗲 𝗚𝗲𝗻𝗲𝗿𝗮𝗹𝗶𝘇𝗲𝗱 𝗤𝘂𝗮𝗻𝘁𝘂𝗺 𝗦𝘁𝗲𝗶𝗻’𝘀 𝗟𝗲𝗺𝗺𝗮 𝗶𝗻 𝗟𝗲𝗮𝗻” (buff.ly/TnHFhZE) at the Lean Seminar in Amsterdam.
🔗 Zoom link: buff.ly/w7DqsRC
🆔 Meeting ID: 610 4772 0375
Reposted by Dave Bacon
Perona and Belongie wondered if they could replace search words with images, but they knew that it would not be easy to convince people to tediously and appropriately tag every object and its parts in millions of pictures.
www.caltech.edu/about/news/p...
www.caltech.edu/about/news/p...
Pietro Perona's Vision: Visipedia and Its Lasting Impact on Computer Vision
The machine learning-driven system for identifying visual information has grown the citizen-science apps Merlin and iNaturalist, led to the development of key datasets, and jump-started the field of i...
www.caltech.edu
October 24, 2025 at 6:14 PM
Perona and Belongie wondered if they could replace search words with images, but they knew that it would not be easy to convince people to tediously and appropriately tag every object and its parts in millions of pictures.
www.caltech.edu/about/news/p...
www.caltech.edu/about/news/p...
Reposted by Dave Bacon
No they do not. I'll try to write something up in the next few days....
October 23, 2025 at 4:36 PM
No they do not. I'll try to write something up in the next few days....
Reposted by Dave Bacon
Are you a computer scientist and don't know what an OTOC is, but want to understand the problem solved in the recent Nature paper by Google Quantum AI? We wrote a 2-page note that explains the motivation and presents a simplified version of the problem for any input size.
scirate.com/arxiv/2510.1...
scirate.com/arxiv/2510.1...
October 23, 2025 at 2:58 AM
Are you a computer scientist and don't know what an OTOC is, but want to understand the problem solved in the recent Nature paper by Google Quantum AI? We wrote a 2-page note that explains the motivation and presents a simplified version of the problem for any input size.
scirate.com/arxiv/2510.1...
scirate.com/arxiv/2510.1...
Reposted by Dave Bacon
In this SFI Seminar, biographer Alec Nevala-Lee explores the life of physicist and Nobel laureate Luis W. Alvarez, whose work spanned the Manhattan Project, investigating the JFK assassination, and developing the asteroid theory of dinosaur extinction.
youtu.be/F4KGgtxNF58
youtu.be/F4KGgtxNF58
October 17, 2025 at 10:18 PM
In this SFI Seminar, biographer Alec Nevala-Lee explores the life of physicist and Nobel laureate Luis W. Alvarez, whose work spanned the Manhattan Project, investigating the JFK assassination, and developing the asteroid theory of dinosaur extinction.
youtu.be/F4KGgtxNF58
youtu.be/F4KGgtxNF58
Reposted by Dave Bacon
Fault-tolerant logical measurement just got a lot faster!
In new work, we show that code surgeries based on hypergraphs, rather than graphs, allow fast and parallel fault-tolerant logical measurements with low qubit overhead (without requiring the code to be single-shot).
arxiv.org/abs/2510.14895
In new work, we show that code surgeries based on hypergraphs, rather than graphs, allow fast and parallel fault-tolerant logical measurements with low qubit overhead (without requiring the code to be single-shot).
arxiv.org/abs/2510.14895
October 17, 2025 at 5:36 AM
Fault-tolerant logical measurement just got a lot faster!
In new work, we show that code surgeries based on hypergraphs, rather than graphs, allow fast and parallel fault-tolerant logical measurements with low qubit overhead (without requiring the code to be single-shot).
arxiv.org/abs/2510.14895
In new work, we show that code surgeries based on hypergraphs, rather than graphs, allow fast and parallel fault-tolerant logical measurements with low qubit overhead (without requiring the code to be single-shot).
arxiv.org/abs/2510.14895
I’ll take “What is the fixed point of LLMs” for $200 Alex.
“Well-meaning” people are using machine translation to write Wikipedia articles in languages that they don’t speak themselves, accelerating the degeneration in quality of the web corpus for several languages with relatively few native speakers.
www.technologyreview.com/2025/09/25/1...
www.technologyreview.com/2025/09/25/1...
How AI and Wikipedia have sent vulnerable languages into a doom spiral
Machine translators have made it easier than ever to create error-plagued Wikipedia articles in obscure languages. What happens when AI models get trained on junk pages?
www.technologyreview.com
October 16, 2025 at 3:36 AM
I’ll take “What is the fixed point of LLMs” for $200 Alex.
Reposted by Dave Bacon
Coming out of social media hibernation to ask:
Are you interested in hosting a future QEC conf?
We are looking for detailed bids for QEC27 over the next month (provisional deadline 21st November). For more info: DM or email me.
QEC26 will be in Santa Barbara
Are you interested in hosting a future QEC conf?
We are looking for detailed bids for QEC27 over the next month (provisional deadline 21st November). For more info: DM or email me.
QEC26 will be in Santa Barbara
October 15, 2025 at 7:44 AM
Coming out of social media hibernation to ask:
Are you interested in hosting a future QEC conf?
We are looking for detailed bids for QEC27 over the next month (provisional deadline 21st November). For more info: DM or email me.
QEC26 will be in Santa Barbara
Are you interested in hosting a future QEC conf?
We are looking for detailed bids for QEC27 over the next month (provisional deadline 21st November). For more info: DM or email me.
QEC26 will be in Santa Barbara
Reposted by Dave Bacon
Dear funding agencies,
I know we all want to discover the wonder drug that will cure the horrible diseases, but to do that, we need to invest in basic, unsexy, foundational research on how the systems work. Funding can’t all be drug development.
Sincerely,
Looking for basic research grants.
I know we all want to discover the wonder drug that will cure the horrible diseases, but to do that, we need to invest in basic, unsexy, foundational research on how the systems work. Funding can’t all be drug development.
Sincerely,
Looking for basic research grants.
October 14, 2025 at 7:24 PM
Dear funding agencies,
I know we all want to discover the wonder drug that will cure the horrible diseases, but to do that, we need to invest in basic, unsexy, foundational research on how the systems work. Funding can’t all be drug development.
Sincerely,
Looking for basic research grants.
I know we all want to discover the wonder drug that will cure the horrible diseases, but to do that, we need to invest in basic, unsexy, foundational research on how the systems work. Funding can’t all be drug development.
Sincerely,
Looking for basic research grants.
Destroying a national treasure.
NASA's Jet Propulsion Laboratory to lay off about 550 workers reut.rs/4302N2L
NASA's Jet Propulsion Laboratory to lay off about 550 workers
NASA's Jet Propulsion Laboratory said on Monday it will cut nearly 550 jobs as part of a restructuring, not related to the current U.S. government shutdown.
reut.rs
October 14, 2025 at 4:13 AM
Destroying a national treasure.
Reposted by Dave Bacon
What if the measurement problem isn't about explaining how the classical world emerges from the quantum world...
...but about what happens when quantum systems interact with something that's already classical?
Turns out, the collapse postulate + Born rule emerge!
scirate.com/arxiv/2510.0...
🧪⚛️🧵1/5
...but about what happens when quantum systems interact with something that's already classical?
Turns out, the collapse postulate + Born rule emerge!
scirate.com/arxiv/2510.0...
🧪⚛️🧵1/5
A one-world interpretation of quantum mechanics
The measurement problem is the issue of explaining how the objective classical world emerges from a quantum one. Here we take a different approach. We assume that there is an objective classical syste...
scirate.com
October 13, 2025 at 7:49 AM
What if the measurement problem isn't about explaining how the classical world emerges from the quantum world...
...but about what happens when quantum systems interact with something that's already classical?
Turns out, the collapse postulate + Born rule emerge!
scirate.com/arxiv/2510.0...
🧪⚛️🧵1/5
...but about what happens when quantum systems interact with something that's already classical?
Turns out, the collapse postulate + Born rule emerge!
scirate.com/arxiv/2510.0...
🧪⚛️🧵1/5