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July 7, 2014 | Hans Ströher (Forschungszentrum Jülich)

10 Years of Georgian-German Science Bridge

Examples from the“Precision Frontier”

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New

ResearchNew

Research

Science – The Endless Frontier

OURKNOWLEDGE

PrecisionPrecision

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An „Experiment“

Characterization of the different outcomes

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Measurements – General

Characterization of the results of measurements

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Measurements – General

Accuracy and Precision

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Measurements – General

Physical Quantity = Numerical Value x Unit

Degree of uncertainty: measurement errors

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Measurements – General

Physical Quantity = Numerical Value x Unit

International System of Units (SI): „metric system“

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Measurements – Length

Physical Quantity = Numerical Value x Unit

Unit of Length: „Meter“ (m)

urmeter

Unit of Length: „Meter“ (m); Tools: scales

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Measurements – Time

Physical Quantity = Numerical Value x Unit

Unit of Time: „Second“ (s); Tools: clocks

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Measurements – Time

Physical Quantity = Numerical Value x Unit

Unit of Time: „Second“ (s); Tools: clocks

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Measurements – Speed

Measurements of speed; control of speed limits

Speed (m/s) = Distance (m) / Time (s)

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1

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Measurements – Speed-of-light (c)

c is a constant of Nature: only fixed expt´ly !

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Measurements – Speed-of-light (c)

(1) Galileo Galilei (1638): c > 10 vsound

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Measurements – Speed-of-light (c)

(2) Ole Rømer (1677): c ~ 213 000 km/s

Moon Io (1,769 days)

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Measurements – Speed-of-light (c)

(3) Middle 19th century: c = (298 000 +- 500) km/s

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Measurements – Speed-of-light (c)

(4) Modern (1970´s): c = (299 792 457.4 +- 1.0) m/s

year of measurement

c (k

m/s

)

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Measurements – Speed-of-light (c)

year of measurement

c (k

m/s

)

1983: fix c =: 299 792 458 m/s defines length unit

!

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2

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Measurements – Neutron Lifetime

Free neutron is an „unstable“ particle

e

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Measurements – Neutron Lifetime

n: very important for light element (H, He) production

How many of the neutrons decay per time intervall? „lifetime“

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Measurements – Neutron Lifetime

Reference value has changed over the years!

~ 2 min

PDG entry

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3

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Increased precison led to a new theory: QED

Measurements – H-Atom „Lamb-Shift“

En

erg

y

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Measurements – µ Magnetic Moment

Discrepancy (~3) between experiment and theory!?

Theoreticalpredictions(„StandardModel of

EPP“)

Most preciseexpt´l data

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4

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Measurements – EDM

Particle „Electric Dipole Moments“ (EDM)

+-

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Measurements – EDM

EDM´s must exist – but they are very small!

Size of the nucleon:

D =10-15 mEDM: 10-15 e m

Nature violates symmetries: expectation:

EDM < 10-25 e m

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< 10-3 m

Measurements – EDM

Measurements up to now: „upper limits“ (zero)

1

Nucleon

1022

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Measurements – EDM

EDMs & matter-antimatter asymmetry of our Universe

Physics: the puzzle of our existence!

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Measurements – EDM

EDMs & matter-antimatter asymmetry of our Universe

JEDIJülich Electric Dipole Moment Investigations

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Accuracy, Precision, Error and Uncertainty

Measurements – Summary

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