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An Atomic Physics Perspective on the New Kilogram Defined by Planck's Constant
An atomic physics perspective on the new kilogram defined by Planck’s constant (Wolfgang Ketterle and Alan O. Jamison, MIT) (Manuscript submitted to Physics Today) On May 20, the kilogram will no longer be defined by the artefact in Paris, but through the definition1 of Planck’s constant h=6.626 070 15*10-34 kg m2/s. This is the result of advances in metrology: The best two measurements of h, the Watt balance and the silicon spheres, have now reached an accuracy similar to the mass drift of the ur-kilogram in Paris over 130 years. At this point, the General Conference on Weights and Measures decided to use the precisely measured numerical value of h as the definition of h, which then defines the unit of the kilogram. But how can we now explain in simple terms what exactly one kilogram is? How do fixed numerical values of h, the speed of light c and the Cs hyperfine frequency νCs define the kilogram? In this article we give a simple conceptual picture of the new kilogram and relate it to the practical realizations of the kilogram. A similar change occurred in 1983 for the definition of the meter when the speed of light was defined to be 299 792 458 m/s. Since the second was the time required for 9 192 631 770 oscillations of hyperfine radiation from a cesium atom, defining the speed of light defined the meter as the distance travelled by light in 1/9192631770 of a second, or equivalently, as 9192631770/299792458 times the wavelength of the cesium hyperfine radiation. -
Units and Magnitudes (Lecture Notes)
physics 8.701 topic 2 Frank Wilczek Units and Magnitudes (lecture notes) This lecture has two parts. The first part is mainly a practical guide to the measurement units that dominate the particle physics literature, and culture. The second part is a quasi-philosophical discussion of deep issues around unit systems, including a comparison of atomic, particle ("strong") and Planck units. For a more extended, profound treatment of the second part issues, see arxiv.org/pdf/0708.4361v1.pdf . Because special relativity and quantum mechanics permeate modern particle physics, it is useful to employ units so that c = ħ = 1. In other words, we report velocities as multiples the speed of light c, and actions (or equivalently angular momenta) as multiples of the rationalized Planck's constant ħ, which is the original Planck constant h divided by 2π. 27 August 2013 physics 8.701 topic 2 Frank Wilczek In classical physics one usually keeps separate units for mass, length and time. I invite you to think about why! (I'll give you my take on it later.) To bring out the "dimensional" features of particle physics units without excess baggage, it is helpful to keep track of powers of mass M, length L, and time T without regard to magnitudes, in the form When these are both set equal to 1, the M, L, T system collapses to just one independent dimension. So we can - and usually do - consider everything as having the units of some power of mass. Thus for energy we have while for momentum 27 August 2013 physics 8.701 topic 2 Frank Wilczek and for length so that energy and momentum have the units of mass, while length has the units of inverse mass. -
Estimation of Forest Aboveground Biomass and Uncertainties By
Urbazaev et al. Carbon Balance Manage (2018) 13:5 https://doi.org/10.1186/s13021-018-0093-5 RESEARCH Open Access Estimation of forest aboveground biomass and uncertainties by integration of feld measurements, airborne LiDAR, and SAR and optical satellite data in Mexico Mikhail Urbazaev1,2* , Christian Thiel1, Felix Cremer1, Ralph Dubayah3, Mirco Migliavacca4, Markus Reichstein4 and Christiane Schmullius1 Abstract Background: Information on the spatial distribution of aboveground biomass (AGB) over large areas is needed for understanding and managing processes involved in the carbon cycle and supporting international policies for climate change mitigation and adaption. Furthermore, these products provide important baseline data for the development of sustainable management strategies to local stakeholders. The use of remote sensing data can provide spatially explicit information of AGB from local to global scales. In this study, we mapped national Mexican forest AGB using satellite remote sensing data and a machine learning approach. We modelled AGB using two scenarios: (1) extensive national forest inventory (NFI), and (2) airborne Light Detection and Ranging (LiDAR) as reference data. Finally, we propagated uncertainties from feld measurements to LiDAR-derived AGB and to the national wall-to-wall forest AGB map. Results: The estimated AGB maps (NFI- and LiDAR-calibrated) showed similar goodness-of-ft statistics (R 2, Root Mean Square Error (RMSE)) at three diferent scales compared to the independent validation data set. We observed diferent spatial patterns of AGB in tropical dense forests, where no or limited number of NFI data were available, with higher AGB values in the LiDAR-calibrated map. We estimated much higher uncertainties in the AGB maps based on two-stage up-scaling method (i.e., from feld measurements to LiDAR and from LiDAR-based estimates to satel- lite imagery) compared to the traditional feld to satellite up-scaling. -
The Mystery of Gravitation and the Elementary Graviton Loop Tony Bermanseder
The Mystery of Gravitation and the Elementary Graviton Loop Tony Bermanseder [email protected] This message shall address the mystery of gravitation and will prove to be a pertinent cornerstone for terrestrial scientists, who are searching for the unification physics in regards to their cosmologies. This message so requires familiarity with technical nomenclature, but I shall attempt to simplify sufficiently for all interested parties to follow the outlines. 1. Classically metric Newtonian-Einsteinian Gravitation and the Barycentre! 2. Quantum Gravitation and the Alpha-Force - Why two mass-charges attract each other! 3. Gauge-Vortex Gravitons in Modular String-Duality! 4. The Positronium Exemplar! 1. Classically metric Newtonian-Einsteinian Gravitation and the Barycentre! Most of you are know of gravity as the long-range force {F G}, given by Isaac Newton as the interaction between two masses {m 1,2 }, separated by a distance R and in the formula: 2 {F G =G.m 1.m 2/R } and where G is Newton's Gravitational Constant, presently measured as -11 -10 about 6.674x10 G-units and maximized in Planck- or string units as G o=1.111..x10 G-units. The masses m 1,2 are then used as 'point-masses', meaning that the mass of an object can be thought of as being centrally 'concentrated' as a 'centre of mass' and/or as a 'centre of gravity'. 24 For example, the mass of the earth is about m 1=6x10 kg and the mass of the sun is about 30 m2=2x10 kg and so as 'point-masses' the earth and the sun orbit or revolve about each other with a centre of mass or BARYCENTRE within the sun, but displaced towards the line connecting the two bodies. -
Improving the Accuracy of the Numerical Values of the Estimates Some Fundamental Physical Constants
Improving the accuracy of the numerical values of the estimates some fundamental physical constants. Valery Timkov, Serg Timkov, Vladimir Zhukov, Konstantin Afanasiev To cite this version: Valery Timkov, Serg Timkov, Vladimir Zhukov, Konstantin Afanasiev. Improving the accuracy of the numerical values of the estimates some fundamental physical constants.. Digital Technologies, Odessa National Academy of Telecommunications, 2019, 25, pp.23 - 39. hal-02117148 HAL Id: hal-02117148 https://hal.archives-ouvertes.fr/hal-02117148 Submitted on 2 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Improving the accuracy of the numerical values of the estimates some fundamental physical constants. Valery F. Timkov1*, Serg V. Timkov2, Vladimir A. Zhukov2, Konstantin E. Afanasiev2 1Institute of Telecommunications and Global Geoinformation Space of the National Academy of Sciences of Ukraine, Senior Researcher, Ukraine. 2Research and Production Enterprise «TZHK», Researcher, Ukraine. *Email: [email protected] The list of designations in the text: l -
Rational Dimensia
Rational Dimensia R. Hanush Physics Phor Phun, Paso Robles, CA 93446∗ (Received) Rational Dimensia is a comprehensive examination of three questions: What is a dimension? Does direction necessarily imply dimension? Can all physical law be derived from geometric principles? A dimension is any physical quantity that can be measured. If space is considered as a single dimension with a plurality of directions, then the spatial dimension forms the second of three axes in a Dimensional Coordinate System (DCS); geometric units normalize unit vectors of time, space, and mass. In the DCS all orders n of any type of motion are subject to geometric analysis in the space- time plane. An nth-order distance formula can be derived from geometric and physical principles using only algebra, geometry, and trigonometry; the concept of the derivative is invoked but not relied upon. Special relativity, general relativity, and perihelion precession are shown to be geometric functions of velocity, acceleration, and jerk (first-, second-, and third-order Lorentz transformations) with v2 coefficients of n! = 1, 2, and 6, respectively. An nth-order Lorentz transformation is extrapolated. An exponential scaling of all DCS coordinate axes results in an ordered Periodic Table of Dimensions, a periodic table of elements for physics. Over 1600 measurement units are fitted to 72 elements; a complete catalog is available online at EPAPS. All physical law can be derived from geometric principles considering only a single direction in space, and direction is unique to the physical quantity of space, so direction does not imply dimension. I. INTRODUCTION analysis can be applied to all. -
The Monopolar Quantum Relativistic Electron an Extension of the Standard Model and Quantum Field Theory
The Monopolar Quantum Relativistic Electron An extension of the standard model and quantum field theory http://www.feynmanlectures.caltech.edu/II_28.html Abstract: Despite the experimental success of the quantum theory and the extension of classical physics in quantum field theory and relativity in special and general application; a synthesis between the classical approach based on Euclidean and Riemann geometries with that of 'modern' theoretical physics based on statistical energy and frequency distributions remains to be a field of active research for the global theoretical and experimental physics community. In this paper a particular attempt for unification shall be indicated in the proposal of a third kind of relativity in a geometric form of quantum relativity, which utilizes the string modular duality of a higher dimensional energy spectrum based on a physics of wormholes directly related to a cosmogony preceding the cosmologies of the thermodynamic universe from inflaton to instanton. In this way, the quantum theory of the microcosm of the outer and inner atom becomes subject to conformal transformations to and from the instanton of a quantum big bang or qbb and therefore enabling a description of the macrocosm of general relativity in terms of the modular T-duality of 11-dimensional supermembrane theory and so incorporating quantum gravity as a geometrical effect of energy transformations at the wormhole scale. Using the linked Feynman lecture at Caltech as a background for the quantum relative approach; this paper shall focus on the way the classical electron with a stipulated electromagnetic mass as a function of its spacial extent exposes the difficulty encountered by quantum field theories to model nature as mathematical point-particles without spacial extent. -
The ST System of Units Leading the Way to Unification
The ST system of units Leading the way to unification © Xavier Borg B.Eng.(Hons.) - Blaze Labs Research First electronic edition published as part of the Unified Theory Foundations (Feb 2005) [1] Abstract This paper shows that all measurable quantities in physics can be represented as nothing more than a number of spatial dimensions differentiated by a number of temporal dimensions and vice versa. To convert between the numerical values given by the space-time system of units and the conventional SI system, one simply multiplies the results by specific dimensionless constants. Once the ST system of units presented here is applied to any set of physics parameters, one is then able to derive all laws and equations without reference to the original theory which presented said relationship. In other words, all known principles and numerical constants which took hundreds of years to be discovered, like Ohm's Law, energy mass equivalence, Newton's Laws, etc.. would simply follow naturally from the spatial and temporal dimensions themselves, and can be derived without any reference to standard theoretical background. Hundreds of new equations can be derived using the ST table included in this paper. The relation between any combination of physical parameters, can be derived at any instant. Included is a step by step worked example showing how to derive any free space constant and quantum constant. 1 Dimensions and dimensional analysis One of the most powerful mathematical tools in science is dimensional analysis. Dimensional analysis is often applied in different scientific fields to simplify a problem by reducing the number of variables to the smallest number of "essential" parameters. -
Should Physical Laws Be Unit-Invariant?
Should physical laws be unit-invariant? 1. Introduction In a paper published in this journal in 2015, Sally Riordan reviews a recent debate about whether fundamental constants are really “constant”, or whether they may change over cosmological timescales. Her context is the impending redefinition of the kilogram and other units in terms of fundamental constants – a practice which is seen as more “objective” than defining units in terms of human artefacts. She focusses on one particular constant, the fine structure constant (α), for which some evidence of such a variation has been reported. Although α is not one of the fundamental constants involved in the proposed redefinitions, it is linked to some which are, so that there is a clear cause for concern. One of the authors she references is Michael Duff, who presents an argument supporting his assertion that dimensionless constants are more fundamental than dimensioned ones; this argument employs various systems of so-called “natural units”. [see Riordan (2015); Duff (2004)] An interesting feature of this discussion is that not only Riordan herself, but all the papers she cites, use a formula for α that is valid only in certain systems of units, and would not feature in a modern physics textbook. This violates another aspect of objectivity – namely, the idea that our physical laws should be expressed in such a way that they are independent of the particular units we choose to use; they should be unit-invariant. In this paper I investigate the place of unit-invariance in the history of physics, together with its converse, unit-dependence, which we will find is a common feature of some branches of physics, despite the fact that, as I will show in an analysis of Duff’s argument, unit-dependent formulae can lead to erroneous conclusions. -
Fundamental Constants and Units and the Search for Temporal Variations
Lecture Notes for the Schladming Winter School "Masses and Constants" 2010. Published in Nucl. Phys. B (Proc. Suppl.) 203-204, 18 (2010) 1 Fundamental constants and units and the search for temporal variations Ekkehard Peika aPhysikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany This article reviews two aspects of the present research on fundamental constants: their use in a universal and precisely realizable system of units for metrology and the search for a conceivable temporal drift of the constants that may open an experimental window to new physics. 1. INTRODUCTION mainly focus on two examples: the unit of mass that is presently realized via an artefact that shall These lectures attempt to cover two active top- be replaced by a quantum definition based on fun- ics of research in the field of the fundamental con- damental constants and the unit of time, which stants whose motivations may seem to be discon- is exceptional in the accuracy to which time and nected or even opposed. On one hand there is a frequencies can be measured with atomic clocks. successful program in metrology to link the real- The second part will give a brief motivation for ization of the base units as closely as possible to the search for variations of constants, will re- the values of fundamental constants like the speed view some observations in geophysics and in as- of light c, the elementary charge e etc., because trophysics and will finally describe laboratory ex- such an approach promises to provide a univer- periments that make use of a new generation of sal and precise system for all measurements of highly precise atomic clocks. -
Planck Dimensional Analysis of Big G
Planck Dimensional Analysis of Big G Espen Gaarder Haug⇤ Norwegian University of Life Sciences July 3, 2016 Abstract This is a short note to show how big G can be derived from dimensional analysis by assuming that the Planck length [1] is much more fundamental than Newton’s gravitational constant. Key words: Big G, Newton, Planck units, Dimensional analysis, Fundamental constants, Atomism. 1 Dimensional Analysis Haug [2, 3, 4] has suggested that Newton’s gravitational constant (Big G) [5] can be written as l2c3 G = p ¯h Writing the gravitational constant in this way helps us to simplify and quantify a long series of equations in gravitational theory without changing the value of G, see [3]. This also enables us simplify the Planck units. We can find this G by solving for the Planck mass or the Planck length with respect to G, as has already been done by Haug. We will claim that G is not anything physical or tangible and that the Planck length may be much more fundamental than the Newton’s gravitational constant. If we assume the Planck length is a more fundamental constant than G,thenwecanalsofindG through “traditional” dimensional analysis. Here we will assume that the speed of light c, the Planck length lp, and the reduced Planck constanth ¯ are the three fundamental constants. The dimensions of G and the three fundamental constants are L3 [G]= MT2 L2 [¯h]=M T L [c]= T [lp]=L Based on this, we have ↵ β γ G = lp c ¯h L3 L β L2 γ = L↵ M (1) MT2 T T ✓ ◆ ✓ ◆ Based on this, we obtain the following three equations Lenght : 3 = ↵ + β +2γ (2) Mass : 1=γ (3) − Time : 2= β γ (4) − − − ⇤e-mail [email protected]. -
Ʌ-Units and Ʌ-Mega Quantum of Action in Their Historical Context
Ʌ-Units and Ʌ-Mega Quantum of action in their historical context Ludwik Kostro, ATENEUM ‒ University of Higher Education, Gdańsk, prof. emeritus at Gdańsk University, Poland, [email protected] Abstract: In Physics we are using conventional units, e.g. nowadays the SI system. Some physicists, among them G. J. Stoney, M. Planck, and Ch. Kittel have introduced into physics the so-called “Natural Units” determi- ned by universal constants. Since several years I am trying to introduce a set of natural units determined by the three Einstein’s constants c, κ = and Ʌ. Since long time in Relativistic Cosmology there are already used some units determined by c, κ and Ʌ: the Ʌ-force = ; Ʌ-pressure of the physical Ʌ Ʌ Ʌ vacuum P = ; Ʌ-mass density ρ = and Ʌ- energy density ρ c = . Ʌ Ʌ Ʌ In my paper (Kostro 2018) there was published the whole list of Ʌ-units. I call them Ʌ- units because they are determined, for the first time, also by the cosmological constant. Among them there are the Mega Units (perhaps Mega Quanta): of Ʌ-Mass M = , of Ʌ-Energy E = ; the Mega Ʌ Ʌ½ Ʌ Ʌ½ Quantum of Ʌ-Action H = . Since some of Ʌ-units can be interpreted Ʌ Ʌ as de Broglie like Ʌ-period T = , Ʌ-frequency v = cɅ½ , Ʌ-ener- Ʌ Ʌ½ Ʌ Ʌ gy EɅ =HɅvɅ and Ʌ-wave length λɅ = and because between the all Ʌ universal constants there ate correlations and interconnections we can ask the question whether in the Nature there are perhaps Ʌ-mega waves, Ʌ- mega fluctuations.