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ROLE OF FUNDAMENTAL PHYSICAL CONSTANTS IN THE NEW SYSTEM OF UNITS – THE QUANTUM SI

ROLE OF FUNDAMENTAL PHYSICAL CONSTANTS IN THE NEW SYSTEM OF UNITS – THE QUANTUM SI. Waldemar Nawrocki 1 and Yury Shukrinov 2 1 - Poznan University of Technology, Poznan , Poland 2 - Joint Institute for Nuclear Research , Dubna, Russia

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ROLE OF FUNDAMENTAL PHYSICAL CONSTANTS IN THE NEW SYSTEM OF UNITS – THE QUANTUM SI

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  1. ROLE OF FUNDAMENTAL PHYSICAL CONSTANTS IN THE NEW SYSTEM OF UNITS – THE QUANTUM SI Waldemar Nawrocki1andYury Shukrinov2 1 - PoznanUniversity of Technology, Poznan, Poland 2 - Joint Institute for NuclearResearch, Dubna, Russia Workshop onPrecision Physics and Fundamental Physical Constants Dubna, December 2011

  2. Role of fundamental physical constants in the new system of units – the quantum SIOutline • History of measures • System International of Units (SI) • Classical standard and qunatum standard • Standards depend on fundamentalphysicalconstants • Resolution of the 23th CGPM of 2007 • Resolution of the 24th CGPM of 2011 • Proposal: the joule to repalce the kelvin as a base unit • Quantum metrological triangle and pyramid

  3. The International System of Units • 1799 – The Standard of the 1 metre and of the 1 kg (Pt+Ir) in Paris. 1 m = 1/10 000 000 fraction of the meridianbetween the pole and the equator. 1 kg = mass of 1/1000 m3fraction of purewater. • 1832r. – Proposal by Carl Gauss1: a system of units with 1 milimeter, 1 gram, 1 second. The base for the CGS system of units. • 1860-1870 – Proposal by Maxwell and Thomson: a coherent system of units with baseunits and derivedunits • 1875 – The MetreConvention, accepted by 17 countries(France, England, Russia, Germany, …). Independent Poland acceptedit in 1925. Standards of 1 metre i 1 kg. • 1954 – MKSA system (metre, kilogram, second, amper). • 1960 – SI (metre, kilogram, second, ampere, kelvin and candela); 1971 - the mole as the 7thbase unit • 1 – C. Gauss Die erdmagnetische Kraft auf ein absolutes Maßzurűckgefűhrt,1832.

  4. System International • System create: • 1. The baseunits: metre, kilogram, second, ampere, • kelvin, candel and mole • 2. The auxiliaryunits: the radian and the steradian • 3. The 22 deriveduntis for electrical, mechanical, magnetic, thermal, light and acousticquantities. Dr Terry Quinn, Director of BIPM (1988-2003), Sevres

  5. The kilogram is the unit of mass; itisequal to the mass of the international prototype of the kilogram. The firstcandidate to be replace by a newdefinition 2. The ampereisthatconstantcurrentwhich, ifmaintained in twostraightparallelconductors of infinitelength, of negligiblecircularcross-section, and placed 1 m apart in vacuum, wouldproducebetweentheseconductors a forceequal to 2 × 10–7 newton per metre of length. 3. The kelvin, unit of thermodynamictemperature, is the fraction 1/273.16 of the thermodynamictemperature of the triple point of water, 4. The mole istheamount of substance of a system whichcointains as many elementaryentities as threareatomsin 0.012 kg of carbon 12. Whenthe mole isused, elementaryentitiesmust be specufied and may be atom, moleculs, ions, electrons, otherparticles, orspecifiedgroups of suchpatrticles. System Internationaldefinitions of the kilogram, ampere, kelvin and mole

  6. 5. The metreis the length of the pathtravelled by light in vacuumduring a time interval of 1/299 792 458 of a second. 6. The secondis the duration of 9 192 631 770 periods of the radiationcorresponding to the transitionbetween the twohyperfinelevels of the ground state of the Cs 133. 7. The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 1012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian. In the above 3 definitionsphysicalconstantsareknownexactly (assumption): c = 299 792 458 m/s  = 9 192 631 770 Hz P = 683 W/steradian System Internationaldefinitions of the metre, second and candela

  7. The 1 kg mass standard, in Central Office of Measures in Warsaw NPL 1 kg standard Pt 90% + Ir 10% D = h = 39 mm

  8. Voltage standards with Josephson junctions Sochocka, Nawrocki, Elektronika, vol. 42 (2001), nr 11.

  9. Quantum Hall Effect Standard at Central Office of Measures in Warsaw (the sample from NPL)

  10. 12th Resolution of the 23th General Conference on Weights and Measures - 2007 23th General Conference considered : “that, of the seven base units of the SI, only the kilogram is still defined in terms of a material artifact – the international prototype of the kilogram (2nd CGPM, 1889) and that the definitions of the ampere, mole and candela depend on the kilogram, …, that many advances, made in recent years, in experiments which relate the mass of the international prototype to the Planck constant h or the Avogadro constant NA,, initiatives to determine the value of a number of relevant fundamental constants, including work to redetermine the Boltzmann constant kB, that as a result of recent advances, there are significant implications for, and potential benefits from, redefinitions of the kilogram, the ampere, the kelvin and the mole …”.

  11. Resolution of the 23th General Conference on Weights and Measures - 2007 Following the above arguments, the 23th General Conference (CGPM) recommended in the 12th resolution: “pursue the relevant experiments so that the International Committee can come to a view on whether it may be possible to redefine the kilogram, the ampere, the kelvin, and the mole using fixed values of the fundamental constants at the time of the 24th General Conference (2011), should, together with the International Committeeand appropriate working groups, work on practical ways of realizing any new definition based on fixed values of the fundamental constants, prepare a mise en pratique for each of them, and consider the most appropriate way of explaining the new definitions to users ...”. www.bipm.org/en/convention/cgpm

  12. Units and Fundamental Physical Constants

  13. Different New Definitions of the 1 kg • The kilogram is the mass of a body whose Compton frequency is 1.356392XXX… × 1050 hertz exactly. (frequency of cosmicray ~ 1024Hz) • The kilogram is the mass of a body whose de Broglie-Compton frequency is equal to exactly [(299 792 4582/(6.626 0693) × 10–34) [hertz ]. • The kilogram is the mass of a body whose equivalent energy is equal to that of a number of photons whose frequencies sum to exactly [(299 792 4582/(66 260 693)] × 1041 hertz. • The kilogram, unit of mass, is such that the Planck constant is exactly h = 6.626 0693 × 10–34Js. • The kilogram is (6.022 1415 × 1023/0.012) times the rest mass of the 12C atom in the ground state. • The kilogram is (6.022 1415 × 1023/0.012) times the rest mass of a particle whose creation energy equals that of a photon whose frequency is: [0.012/(6.022 1415 × 1023) × 299 792 4582/66 260 693 × 10–34) [hertz]. 7. The kilogram is 1.097 769 24 × 1030 times the rest mass of the electron.

  14. The Si sphere – the possible standard of the 1 kilogram • Siliconsphereat the PTB, Braunschweig • D = 90 mm • diametercontrolled in 16 000 directions • 2 mln Euro

  15. New definitions of ampere, kelvin and mole • The ampere is the electrical current equivalent to the flow of exactly 1/(1.602 176 53 × 10-19) elementary charges per second. 2. The kelvin is the change of thermodynamic temperature T that results in a change of thermal energy kTby exactly 1.380 6488 × 10–23 joule, where k is the Boltzmann constant. 3. The mole is the unit of amount of substance. It is equal to 6.022 1415 × 1023 mol-1 specified identical entities. The entities may be atoms, ions, molecules or other particles.

  16. Resolution of the 24th General Conference on Weights and Measures - 2011 The 24th General Conference (17-21 October 2011) considered: “that, although the work (to redefine four base units of the SI) has progressed well, not all the requirements set out by the 23th General Conference in 2007 have been satisfied and so the International Committee for Weights and Measures isnot yet ready to make a final proposal.” The definitions of the metre, kilogram, second, ampere, kelvin, mole and candela will be abrogared (will be canceled). The 24th General Conference „invites CODATA to continue provide adjusted values of the fundamental physical constants based on all relevant information available and to make the results known to the International Committee through its Consultative Committee for Units since these CODATA values and uncertainties will be those for the revised SI, …” www.bipm.org/en/convention/cgpm

  17. Resolution of the 24th General Conference, 2011, Possible New Definitions for Units The 24th General Conference takenoteof intention of the International Committee for Weights and Measuresto propose a revision of the SI as follows: The International System of Units, the SI,will be the system of units in which: • the ground state hyperfine splitting frequency of the caesium 133 atom (133Cs)hfs is exactly9 192 631 770 hertz, 2. the speed of light in vacuum c0 is exactly299 792 458 metre per second, 3. the Planck constant h is exactly6.626 06X × 10–34 joule second, 4. the elementary charge e is exactly1.602 17X × 10-19 coulomb, 5. the Boltzmann constant kB is exactly1.380 6X × 10–23 joule per kelvin, 6. the Avogadro constant NA is exactly6.022 14X × 1023reciprocal mole, 7. the luminous efficacy Kcdof monochromatic radiation of frequency 540 × 1012 hertz is exactly683 lumen per watt.

  18. Fundamental physical constants from CODATA How does the h change? Table on the building of the Nicolaus Copernicus University,Toruń, Poland „The symbol X in this draft represents one or more additional digits to be added to the numerical values of h, e, k and NA using values based on the most recent CODATA adjustment” – Resolution of 24th CGPM

  19. Quantum metrological triangle 1. Josephsoneffect: Nobel Prize for Brian D. Josephson (1973) 2. Qunatum Hall effect (QHE) Nobel Prize for Klaus von Klitzing (1985) 3. Single electrontunneling Will be the Nobel Prize for Likharev and Averin? Likharev, Zorin, Jour. Low Temp. Physics, vol. 59 (1985)

  20. Qunatum metrological pyramid Nawrocki W., Revising the SI: the joule to replace the Kelvin as a base unit, Metrology and Measurement Systems, vol. 13 (2006)

  21. Joule instead of Kelvin • Proposal: • Replacementthekelvin, the unit for temperature, withthejoule, the unit for energy (work and heat) . Nawrocki W., Revising the SI: the joule to replace the Kelvin as a base unit, Metrology and Measurement Systems, vol. 13 (2006)

  22. Arguments for the replacement: Joule instead fo Kelvin • 1. Energyisperhaps the most universal of allphysicalquantities in nature The totalquantity of energy in the universeremainsconstant(1st low of thermodynamics) • 2. Energyis a commonobject of trade on a largescale • 3. Differentforms of energyallow to compare standard of mechanical, thermal, electricalquantities to the E = h f; E = mc2; E = U I t; E = F l; E = kBT; E = m v2/2; Q =chmT • 3. The definition of jouleaccording SI and for baseunitsantowych 1J = m2 kg s-2 1J = V2 s -1 4. Measurement resolution limitsaccording to the Heisenberg`sformulas x·p h E·t h

  23. System of basic units - proposal

  24. Poznań – Old Market Square Conclusion: The role of fundamental physical constants for system of units is very large

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