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Preview: How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy Variational calculus A2: Too much symmetry Group theory A3: Ensemble averaging Statistical mechanics Master equations A4: The system is too noisy Kraus operators (sometimes called measurement operators) Product-sum representations (both separated and linked) What these techniques have in common: They reduce the system complexity class from EXP to P Historically, they are all linked to beautiful physics and deep mathematics, They have great utility for quantum system engineering (the focus of this talk) the least-studied class of quantum analysis methods Quantum system engineering is stimulating new approaches in math and physics
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Page 1: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

Preview: How can we be sure a physical system is not running a (possibly occult) quantum computation?

Preview: How can we be sure a physical system is not running a (possibly occult) quantum computation?

• A1: Not enough energy– Variational calculus

• A2: Too much symmetry– Group theory

• A3: Ensemble averaging – Statistical mechanics– Master equations

• A4: The system is too noisy– Kraus operators (sometimes called measurement operators)– Product-sum representations (both separated and linked)

• What these techniques have in common:– They reduce the system complexity class from EXP to P– Historically, they are all linked to beautiful physics and deep mathematics,– They have great utility for quantum system engineering (the focus of this talk)

the least-studied class of quantum analysis methods

Quantum system engineering is stimulating new approaches

in math and physics

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October 11, 2005UW Condensed Matter Seminar

White paper available at

www.mrfm.org

Kick-off meeting: November 13, 2005

Emerging Techniques for Solving Emerging Techniques for Solving NP-Complete Problems in NP-Complete Problems in Mathematics, Biology, Mathematics, Biology, Engineering, … and PhysicsEngineering, … and Physics

Presented by:

The Quantum System Engineering GroupUniversity of WashingtonSeattle, Washington, USA

Personnel:Personnel:

Joseph L. GarbiniJohn JackyJohn SidlesDoug Mounce

Students:Students:Joe MalcombKristi GibbsChris KikuchiTony Norman

UWMICORNUWMICORN Collaboration: Collaboration:

Al Hero / MichiganJohn Marohn / CornellDoran Smith / ARODan Rugar / IBM

UWMICORNUWMICORN++++Chris Hammel / Ohio StateRaffi Budakian / IllinoisMike Roukes / CalTechKeith Schwab / Cornell

This talk is a blueprint for integrated technology

development

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1959: Richard FeynmanThere’s Plenty of Room at the Bottom

1946: John von Neumann to Norbert WeinerElectron microscopyCrystallography

1946: Linus PaulingSystem biology proposal to Rockefeller Foundation

I put this out as a challenge: Is there no way to make the electron microscope more powerful? … Make the microscope one hundred times more powerful, and many problems of biology would be made very much easier.

I put this out as a challenge: Is there no way to make the electron microscope more powerful? … Make the microscope one hundred times more powerful, and many problems of biology would be made very much easier.

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There is no telling what really advanced electron microscopic techniques will do. In fact, I suspect that the main possibilities lie in that direction.

There is no telling what really advanced electron microscopic techniques will do. In fact, I suspect that the main possibilities lie in that direction.

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It is appalling to consider how meager is our information about the composition and structure of proteins … Extremely important advances could be achieved if the effective resolving power of the electron microscope could be considerably improved.

It is appalling to consider how meager is our information about the composition and structure of proteins … Extremely important advances could be achieved if the effective resolving power of the electron microscope could be considerably improved.

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The Historic Challenge of Quantum MicroscopyThe Historic Challenge of Quantum MicroscopyThe Historic Challenge of Quantum MicroscopyThe Historic Challenge of Quantum Microscopy

Pauling, von Neumann, and Feynman shared a vision and issued a challenge;

now we’re going to fulfill it

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FAQ: Program for Single Nuclear Spin DetectionFAQ: Program for Single Nuclear Spin DetectionFAQ: Program for Single Nuclear Spin DetectionFAQ: Program for Single Nuclear Spin Detection

Q1: What is a reasonable technical path to single-nuclear-spin detection?

Q2: What are appropriate performance metrics and technical milestones?

Q3: When might this technology reasonably be ready?

Q4: What tasks could this technology accomplish?

Q5: Are we confident that quantum microscopy will work?

Q6: How can this technology help winthe Global War on Terror (GWOT)?

Q7: What is the logical next step?

A1: The path is smaller, colder, quieter device development

A2: The metric is bits-per-second received from each target spin

A3: By 2010, if historic rates of progress are sustained

A4: Comprehensive access to resources of “chemical space”

A5:A5: We’ll know soon. E2e analysis We’ll know soon. E2e analysis and emulation now feasibleand emulation now feasible

A6: New resources are a strategic requirement for GWOT victory

A7: a satellite-scale integrated launch program: MOQSI

This talk’s key question:will quantum microscopy work?

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Moore’s Law Progress in MRFMMoore’s Law Progress in MRFM

• smaller• colder • quieter

• smaller• colder • quieter

Moore’sLaw

designrules

Moore’sLaw

designrules

• MRFM sensitivity has improved by 140 dB in twelve years

• Equivalent to doubling sensitivity every 3.1 months for 46 doublings

• MRFM has Moore’s Scaling: smaller, colder, quieter devices work better

The Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQ

Q1: What is a reasonable technical path to single-nuclear-spin detection?

A1: The path is smaller, colder, quieter device development

We’re well underway,with a clear path forward

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The Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQ

Q2: What are appropriate performance metrics and technical milestones?

A2: The metric is bits-per-second received from each target spin

• Jiro Horikoshi and John Boyd

• Channel capacity is a good choice for an MRFM design metric because it:

— Directly reflects the mission,(gain information from spins)

— Provides strategic guidance for device design

— Establishes fundamental physical bounds on performance

Good design metrics reflect the overall mission

Horikoshi: Eagles of Mitsubishi

Boyd: Boyd: US Flight Test Manual (FTM108)US Flight Test Manual (FTM108)

UWMICORN:UWMICORN: Program for Achieving Program for Achieving Single Nuclear Spin Detection Single Nuclear Spin Detection

Informatic capacityis our primary metric

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1992 20102004

Quantum biomicroscopy has plenty of SNR headroom

Page 8: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

The Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQ

Q3: When might this technology reasonably be ready?

A3: By 2010, if historic rates of progress are sustained

• Sustaining MRFM progress requiresthree coordinated efforts:

– Synthesizing engineering principlesfrom the emerging nanoscale physics.

– Fabricating the next generation of devices: smaller, colder, and quieter,

– Testing these devices in real-world imaging environments

• Shigeo Shingo and Taichii Ohno

1982

1998after 17 years’pursuit of

engineeringperfection,

Caves’ quantumlimits wereachieved

Lesson: quantum system engineering (QSE) is “The unrelenting pursuit of engineering perfection”

Approaching the quantum limits will require a sustained

technological effort

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The Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQ

Q4: What tasks could this technology accomplish?

A4: Comprehensive access to resources of “chemical space”

A project far larger than the Genome Project (from the on-line White Paper):

NatureNature 432, p. 823 (2004) 432, p. 823 (2004)

• Every cell contains as 100X as many atoms as there are stars in the galaxy.

• Surveying this nearly-infinite domain will be the largest scientific project that humanity has ever undertaken.

• The knowledge gained will be the 21st Century’s greatest resource

This technology helps provide Dirac’s foundation for a Golden Age:

“Ordinary people can make   extraordinary contributions”

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Q5: Are we confident that quantum microscopy will work?

A5: We’ll know soon. E2e analysis and emulation now feasible

NP-hard

EXP

NP

P

engineeringcomplexityclasses

• P: derive and check using polynomialmemory and time resources

– E.g., compute a transfer function

• NP: via a decision “certificate”, verify with polynomial resources

– E.g, does a stable controller exist?

• NP-hard: typically, the optimization or interval version of an NP problem

– E.g., does a stable controller exist over an interval of model parameters?

– In practice, “solved” by robust design heuristics, backed by Monte-Carloemulation and instance certificates

• EXP: emulation requires exponential resources, and no certificates known

– problems in EXP are inaccessible – Quantum system engineering

must move from EXP to P

Quantum analysis techniquesthat reside in NP, not EXP,

are a mission-critical requirement

Page 11: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

The orthodoxy of “Mike and Ike”:

All quantum simulations are equivalent to …The orthodoxy of “Mike and Ike”:

All quantum simulations are equivalent to …

• Objective: compute the wave function in P-time and store it in P-space

• Strategic insight: tune the noise to “compress” the Hilbert space trajectory

• First requirement: the compressed trajectory must fit in P-space

• Second requirement: the compression algorithm must run in P-time

Chapters1,2,8,9

The analysis tools we needare already in the literature

details: quant-ph/0401165

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The order and connection of ideas is the same The order and connection of ideas is the same as the order and connection of things … as the order and connection of things … SpinozaSpinoza

• Construct A and B operators from optical transfer matrices

• Recognize that A and B are Kraus operators (which generate POVMs)

• Recognize that interferometer “tuning invariance” is just Choi’s Theorem

Kraus operators map one-to-one onto standard engineering hardware;

this motivates novel applications

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“jump”reservoir

“noise”reservoir

“measurement”reservoir

measured data

spin dynamics

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“jump”reservoir

“noise”reservoir

“measurement”reservoir

measured data

spin dynamics

Q5: Are we confident that quantum microscopy will work?

A5.1: Quantum emulation of the IBM single-spin experiment

IBM’s 13-hour single-spin experiment can be

efficiently simulated

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Q5: Are we confident that quantum microscopy will work?

A5.2: Generalize to higher-dimensional spin systems

• Exact 18-spin quantum trajectories yield QDE CDFs that are restricted to an exponentially small fraction of Hilbert space

• This is good news, because such low entropy values assure us that a compression algorithm must exist (but do not provide an explicit example)

• Now we are motivated to search for an explicit algorithm that consumes only P-space and P-time resources (see next three slides)

Numerical simulations ofhigh-temperature spin dust

– a deliberately tough challenge –

•no spatial symmetry•no spatial ordering• random dipole coupling•noisy environment

tough to simulate

QDE of spin dustwith synopticnoise tuning

QDE of spin dustwith ergodicnoise tuning

QDE of randomproduct states(analytic result)

quantum dispersion entropy (QDE)

cu

mu

lati

ve

dis

trib

uti

on

fu

nc

tio

n (

CD

F)

18-spin quantum dispersion entropy values

QDE of randomHilbert states

(analytic result)

Replacing quantum noise with covert quantum measurement yields

compressed Hilbert space trajectories

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Q5: Are we confident that quantum microscopy will work?

A5.3: Beylkin & Mohlenkamp’s algo-rithms provide a vital tool

• Separated representations provide a “JPEG format” for compressing quantum state trajectories

• They efficiently compress all Hilbert states except the high-rank states employed in quantum computation

• They are well-suited to quantum system engineering

Compressed Hilbert trajectoriescan be stored in P-space and

computed in P-time

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Q5: Are we confident that quantum microscopy will work?

A5.4: Separated reps perform well even in “tough” spin systems

synopticnoise tuning

ergodicnoise tuning

rank = 1 rank = 2

rank = 5 rank = 10

rank = 20 rank = 30

number of spins

fid

eli

tyfi

de

lity

fid

eli

ty

number of spins

fidelity of separated representationsNumerical simulations ofhigh-temperature spin dust

– a deliberately tough challenge –

•no spatial symmetry•no spatial ordering• random dipole coupling•noisy environment

tough to simulate

These techniques are robust: they work even at high temperatureand in the absence of symmetries

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Q5: Are we confident that quantum microscopy will work?

A5.5: Now, large-scale quantum spin systems can be analyzed in P-time

Q: How can we emulate thousands of quantum spins with polynomial space and time resources?

• The mission-critical MURI/MOQSI objectives:– Reliably predict strong-gradient quantum spin physics– Maximize system performance metrics– Build confidence that MURI/MOQSI will go all the way

A: Apply linked quantum representation theory(as summarized in five paragraphs … )

P-time quantum system simulation is a mission-critical capability

that is now coming on-line

By definition, a linked representation is a separated representation subjected to linear constraints (the “wire-ties”)

Page 19: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

• High-level system simulation is central to modern strategic capability

Q5: Are we confident that quantum microscopy will work?

A5.6: Large-scale quantum system simulations will tell us

• Open high-level simulations build open strategic advantage (OSA)– Builds technical confidence: “If we build it, it will work”

– Creates trans-national business alliances: “We want to be part of your strategy”

– Establishes open strategic advantage: “Deceive the sky to cross the ocean”

Open strategic advantage (OSA) strategies are easy to understand,

impossible to stop, and yield global strategic advantages

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• Strategically, MURI/MOQSI is a 21st Century “Corps of Discovery”

• Deploy our new quantum system engineering simulation tools– Build technical confidence and catalyze alliances: “If we build it, we it will work”

• Embrace and extend the open strategic advantage of biospace

• Maximize job creation and entrepreneurial opportunity – For strong impact: deploy 5K imaging devices at $1M each– For maximal impact: deploy 1M devices at $5K each;– The informatic harvest is ~3 petacoordinates per year– This yields the “Chris Kikuchi Open Strategic Advantage”

• Achieve all that our forebears challenged us to accomplish

Q5: Are we confident that quantum microscopy will work?

A5.7: As confident as Thomas Jefferson in the Army’s “Corps of Discovery”

19th Century  21st Century

Louisiana Territory biospace frontier

Missouri River quantum microscopy

Corps of Discovery MURI and MOQSI

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MURI/MOQSI is a 21st Century “Corps of Discovery” – opening

a new & unbounded frontier

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The Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQThe Path to Single Nuclear Spin Detection: FAQ

Q6: How can this technology help win the Global War on Terrorism (GWOT)?

A6: New resources are a strategic requirement for GWOT victory

Q5Q5**:: How can we eliminate terrorism’s primary resources: How can we eliminate terrorism’s primary resources: hunger, poverty, desperation, and chaos?hunger, poverty, desperation, and chaos?

A5A5**:: New resources, new projects, and new kinds of work New resources, new projects, and new kinds of work all support a pivotal strategic objective: creating all support a pivotal strategic objective: creating one billion jobs in the next twenty yearsone billion jobs in the next twenty years

We must win the GWOT; failure is not an option.

New resources are a vital need.

Page 22: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

• Year 1: Demonstrate technology and build community– Milestone I: Close-approach electric noise in wet, salty samples

– Milestone II: 3D bioimages with viral-scale resolution

– Milestone III: E2e quantum system design via P-time algorithms

– Primary objective I: technical and strategic consensus

– Primary objective II: a team to take it all the way.

• Year 2: Launch MOQSI (draft white paper: Nov. 2005)– Mechatronic and Optical Quantum Sensing Initiative

– Five-year at $10M/year in support of five MOQSI Groups

• Year 3: Commercial development platforms– JEOL, Oxford, Digital Instruments

• Year 4: Pursuit of “smaller, sharper, colder, cleaner”– With confidence that “If we build it, it will work”.

• Year 5: Single-proton resolution in a bioimaging context

Q7: What is the logical next step? A7: A satellite-scale integrated launch program: MOQSI

If we build it, it will work.

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We must win the GWOT; failure is not an option.

New resources are a vital need.

“Power, before it comes from arms or wealth, emanates from ideas”

The Power of Mathematics The Power of Knowledge

The Power of DiscoveryThe Power of Resources

“Ordinary people can make   extraordinary contributions”

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K. N. Cukier

Caroline Herschel

Baruch Spinoza

Anton van Leeuwenhoek

RobertHooke

Linus Pauling

Richard Feynman

John vonNeumann

BarbaraMcClintock

Lynn Margulis

Jane Goodall

Walter Reed

Page 24: Preview:How can we be sure a physical system is not running a (possibly occult) quantum computation? A1: Not enough energy – –Variational calculus A2:

Thank you


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