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1
Flowers, Jeff L., and Brian W. Petley. "Planck, units, and modern metrology." Annalen der Physik 17, no. 2-3 (2008): 101–14. http://dx.doi.org/10.1002/andp.200710277.
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Min, Brian B. K. "The photon element units and their relativistic properties." Physics Essays 33, no. 1 (2020): 38–45. http://dx.doi.org/10.4006/0836-1398-33.1.38.
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A set of natural units is determined from the “photon element” model of light, the outcome of an extended Compton analysis. In terms of these units, the speed of light and the electrical and Boltzmann constants are, respectively, on the order of unity, but the Planck constant is ∼1027 or greater and gravitational constant ∼10−59 or greater. This makes the photon element units less convenient than the Planck units. With the mass unit that is only ∼10−43 of the Planck mass, however, the photon element units can correspond better to physical realities than the Planck units. For the spacetime, a photon element forms a set of unit base vectors, a natural basis that is Lorentz covariant. There an analysis shows that (1) of the above five universal constants all are Lorentz invariants except the gravitational constant, and (2) of the five natural units (time, length, mass, electrical charge, and temperature,) only the electrical charge is a Lorentz invariant.
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Sharupov, Oleg. "PLANCK UNITS AND EXTENDED SPECIAL RELATIVITY." Respublica literaria, no. 1 (December 25, 2020): 65–67. http://dx.doi.org/10.47850/s.2020.1.18.
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The Planck length is an object of the relativistic quantum-gravitational theory, therefore, a more general and consistent direction of the special relativity extension, seems to be the use of the postulate of the relativistically invariant and limiting nature of all Planck units, that was introduced by V.V. Korukhov at the end of the 90s. One of the examples of the implementation of this postulate in its methodological meaning is the model of a vacuum-like medium, the physical properties of which are characterized by relativistically invariant values, which qualita-tively distinguishes it from the known types of matter –matter and field.
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Kirakosyan, Khachatur A. "To the Content of Planck Units." Theoretical Physics 3, no. 2 (2018): 33–37. http://dx.doi.org/10.22606/tp.2018.32002.
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Bunker, P. R., Ian M. Mills, and Per Jensen. "The Planck constant and its units." Journal of Quantitative Spectroscopy and Radiative Transfer 237 (November 2019): 106594. http://dx.doi.org/10.1016/j.jqsrt.2019.106594.
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Humpherys, David. "Measuring Planck’s Constant With Compton Scattering." Applied Physics Research 15, no. 1 (2023): 24. http://dx.doi.org/10.5539/apr.v15n1p24.
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Measured values of the electron mass and Compton wavelength yield a value of Planck’s constant with a relative standard
 uncertainty of 3 × 10−10. This is only slightly larger than the 1.3 × 10−10 relative standard uncertainty in measurements
 performed using the Kibble balance. Compton scattering presents an alternative pathway for improving the value of
 Planck’s constant.
 Natural units of length, mass, and time offer viable solutions for improving the values of physical constants. While
 extensive values of the Planck units lie beyond the reach of present-day instrumentation, certain product and quotient
 pairs of Planck units such as the speed of light can be measured with relatively high precision. Better measurements of
 certain unit pairs will improve the value of the gravitational constant.
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Flowers, Jeff L., and Brian W. Petley. "Planck, units, and modern metrology *." Annalen der Physik 520, no. 2-3 (2008): 101–14. http://dx.doi.org/10.1002/andp.200852002-307.
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Nikonenko, K. L. "On some conclusions from the relations of Planck quantities." Bulletin of State University of Education. Series: Physics and Mathematics, no. 4 (February 26, 2025): 54–85. https://doi.org/10.18384/2949-5067-2024-4-54-85.
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Aim. Search for a variant of the LT system of units that is maximally consistent with the international SI and the subsystems of the CGS system of units.Methodology. The analysis of the ratios of physical quantities in the international SI, CGS subsystems and Planck LT systems of units is carried out. A method is proposed for determining the values of physical quantities according to the criterion of the maximum degree of consistency between the recommended CODATE values of constants for defining coupling equations.Results. Conditionally accurate values of the Planck length are obtained ℓp = 1.616255272206877 ∙ 10-35 ∙ 𝑚, the fine structure constant 𝛼 = 7.297352564390205 ∙ 10-3, and a number of other physical constants were obtained. A variant of the Planck LT system of units is proposed and the conversion coefficients between the electromagnetic quantities of the analyzed systems of units are clarified.Research implications. It consists in the possibility of using the PLT system of units and conditionally accurate values of a number of physical constants for computational methods and mathematical models of physical processes in various fields of science and technology.
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Stock, M. "The watt balance: determination of the Planck constant and redefinition of the kilogram." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1953 (2011): 3936–53. http://dx.doi.org/10.1098/rsta.2011.0184.
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Since 1889, the international prototype of the kilogram has served as the definition of the unit of mass in the International System of Units (SI). It is the last material artefact to define a base unit of the SI, and it influences several other base units. This situation is no longer acceptable in a time of ever-increasing measurement precision. It is therefore planned to redefine the unit of mass by fixing the numerical value of the Planck constant. At the same time three other base units, the ampere, the kelvin and the mole, will be redefined. As a first step, the kilogram redefinition requires a highly accurate determination of the Planck constant in the present SI system, with a relative uncertainty of the order of 1 part in 10 8 . The most promising experiment for this purpose, and for the future realization of the kilogram, is the watt balance. It compares mechanical and electrical power and makes use of two macroscopic quantum effects, thus creating a relationship between a macroscopic mass and the Planck constant. In this paper, the operating principle of watt balance experiments is explained and the existing experiments are reviewed. An overview is given of all available experimental determinations of the Planck constant, and it is shown that further investigation is needed before the redefinition of the kilogram can take place. Independent of this requirement, a consensus has been reached on the form that future definitions of the SI base units will take.
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Abdukadyrov, Askar. "Fundamental Units of Measurement and Extra Dimensions." Advances in High Energy Physics 2022 (November 2, 2022): 1–3. http://dx.doi.org/10.1155/2022/2655733.
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The space available to our perception is three-dimensional with full evidence. The development of physics led to the hypothesis of extra dimensions. It is believed that an important role in the unification of physics should play by the Planck units of mass, length and time, built on the universal constants c (the speed of light in a vacuum), G (the gravitational constant), and ħ (the reduced Planck constant). In August 2021, published work in which it is shown that the fundamental role in the unification of physics, in fact, was played by the Stoney units, built on the universal constants c − G − e or c − G − ħ and α (where e is the elementary electric charge, and α is the fine-structure constant). Using this result, the presented work offers a possible solution to the riddle of extra dimensions; it is shown that any additional spatial dimension can be expressed in terms of the fundamental length or the product of the fundamental time and the speed of light in a vacuum.
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Christodoulou, Dimitris M., and Demosthenes Kazanas. "The Upgraded Planck System of Units That Reaches from the Known Planck Scale All the Way Down to Subatomic Scales." Astronomy 2, no. 4 (2023): 235–68. http://dx.doi.org/10.3390/astronomy2040017.
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Natural systems of units {Ui} need to be overhauled to include the dimensionless coupling constants {αUi} of the natural forces. Otherwise, they cannot quantify all the forces of nature in a unified manner. Thus, each force must furnish a system of units with at least one dimensional and one dimensionless constant. We revisit three natural systems of units (atomic, cosmological, and Planck). The Planck system is easier to rectify, and we do so in this work. The atomic system discounts {G,αG}, thus it cannot account for gravitation. The cosmological system discounts {h,αh}, thus it cannot account for quantum physics. Here, the symbols have their usual meanings; in particular, αG is the gravitational coupling constant and αh is Dirac’s fine-structure constant. The speed of light c and the impedance of free space Z0 are resistive properties imposed by the vacuum itself; thus, they must be present in all systems of units. The upgraded Planck system with fundamental units UPS:={c,Z0,G,αG,h,αh,…} describes all physical scales in the universe—it is nature’s system of units. As such, it reveals a number of properties, most of which have been encountered previously in seemingly disjoint parts of physics and some of which have been designated as mere coincidences. Based on the UPS results, which relate (sub)atomic scales to the Planck scale and the fine-structure constant to the Higgs field, we can state with confidence that no observed or measured physical properties are coincidental in this universe. Furthermore, we derive from first principles Koide’s K=2/3 enigmatic constant and additional analogous quark and vector boson constants. These are formal mathematical proofs that justify a posteriori the use of geometric means in deriving the quark/boson mass ladder. This ladder allows us to also calculate the Higgs couplings to the vector bosons and the Weinberg angle in terms of K only, and many of the “free” parameters of the Standard Model of particle physics were previously expected to be determined only from experiments.
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Iorio, Lorenzo. "Perspectives on Constraining a Cosmological Constant-Type Parameter with Pulsar Timing in the Galactic Center." Universe 4, no. 4 (2018): 59. http://dx.doi.org/10.3390/universe4040059.
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Independent tests aiming to constrain the value of the cosmological constant Λ are usually difficult because of its extreme smallness ( Λ ≃ 1 × 10 - 52 m - 2 , or 2 . 89 × 10 - 122 in Planck units ) . Bounds on it from Solar System orbital motions determined with spacecraft tracking are currently at the ≃ 10 - 43 – 10 - 44 m - 2 ( 5 – 1 × 10 - 113 in Planck units ) level, but they may turn out to be optimistic since Λ has not yet been explicitly modeled in the planetary data reductions. Accurate ( σ τ p ≃ 1 – 10 μ s ) timing of expected pulsars orbiting the Black Hole at the Galactic Center, preferably along highly eccentric and wide orbits, might, at least in principle, improve the planetary constraints by several orders of magnitude. By looking at the average time shift per orbit Δ δ τ ¯ p Λ , an S2-like orbital configuration with e = 0 . 8839 , P b = 16 yr would permit a preliminarily upper bound of the order of Λ ≲ 9 × 10 - 47 m - 2 ≲ 2 × 10 - 116 in Planck units if only σ τ p were to be considered. Our results can be easily extended to modified models of gravity using Λ -type parameters.
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Haug, Espen Gaarder. "Progress in the Composite View of the Newton Gravitational Constant and Its Link to the Planck Scale." Universe 8, no. 9 (2022): 454. http://dx.doi.org/10.3390/universe8090454.
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The Newtonian gravity constant G plays a central role in gravitational theory. Researchers have, since at least the 1980s, tried to see if the Newton gravitational constant can be expressed or replaced with more fundamental units, such as the Planck units. However, it was already pointed out in 1987 that this led to a circular problem; namely, that one must know G to find the Planck units, and that it is therefore of little or no use to express G through the Planck units. This is a view repeated in the literature in recent years, and is held by the physics’ community. However, we will claim that the circular problem was solved a few years ago. In addition, when one expresses the mass from the Compton wavelength formula, this leads to the conclusion that the three universal constants of G, h, and c now can be replaced with only lp and c to predict observable gravitational phenomena. While there have been several review papers on the Newton gravitational constant, for example, about how to measure it, we have not found a single review paper on the composite view of the gravitational constant. This paper will review the history of, as well as recent progress in, the composite view of the gravitational constant. This should hopefully be a useful supplement in the ongoing research for understanding and discussion of Newton’s gravitational constant.
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SINGH, T. P. "NONCOMMUTATIVE GRAVITY, A "NO STRINGS ATTACHED" QUANTUM–CLASSICAL DUALITY, AND THE COSMOLOGICAL CONSTANT PUZZLE." International Journal of Modern Physics D 17, no. 13n14 (2008): 2593–98. http://dx.doi.org/10.1142/s0218271808014126.
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There ought to exist a reformulation of quantum mechanics which does not refer to an external classical space–time manifold. Such a reformulation can be achieved using the language of noncommutative differential geometry. A consequence which follows is that the "weakly quantum, strongly gravitational" dynamics of a relativistic particle whose mass is much greater than the Planck mass is dual to the "strongly quantum, weakly gravitational" dynamics of another particle whose mass is much less than the Planck mass. The masses of the two particles are inversely related to each other, and the product of their masses is equal to the square of the Planck mass. This duality explains the observed value of the cosmological constant, and also why this value is nonzero but extremely small in Planck units.
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Humpherys, David. "The Implicit Structure of Planck’s Constant." European Journal of Applied Physics 4, no. 6 (2022): 22–25. http://dx.doi.org/10.24018/ejphysics.2022.4.6.227.
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Max Planck derived natural units of length, mass, and time on the assumption that each of the universal constants embodies natural units in its unit dimensions. The four natural units and dimensions comprising Planck’s constant infuse more granular elements into the formulas enriching our understanding of the physical constants and the phenomena they represent. The natural units offer a consistent language for comparing classical and quantum mechanical formulas.
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Haug, Espen Gaarder. "Gravity Without Newton’s Gravitational Constant and No Knowledge of the Mass Size." European Journal of Applied Physics 4, no. 6 (2022): 4–10. http://dx.doi.org/10.24018/ejphysics.2022.4.6.223.
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In this paper, we show that the Schwarzschild radius can be extracted easily from any gravitationally-linked phenomena without having knowledge of Newton’s gravitational constant or the mass size of the gravitational object. Further, the Schwarzschild radius can be used to predict a long series of gravity phenomena accurately, again without knowledge of Newton’s gravitational constant and also without knowledge of the size of the mass, although this may seem surprising at first. Hidden within the Schwarzschild radius are the more fundamental mass of the gravitational object, the Planck length, which we will assert contain the secret essence related to gravity, in addition to the speed of light (the speed of gravity). This seems to support that gravity is quantized, even at the cosmological scale, and this quantization is directly linked to the Planck units. This also supports our view that Newton’s gravitational constant is a universal composite constant of the form G = l2pc3/h , rather than relying on the Planck units as a function of G. This does not mean that Newton’s gravitational constant is not a universal constant, but rather that it is a composite universal constant, which depends on the Planck length, the speed of light, and the Planck constant. This is, to our knowledge, the first paper1 that shows how a long series of major gravity predictions and measurements can be completed without any knowledge of the mass size of the object, or Newton’s gravitational constant. At minimum, we think it provides an interesting new angle for evaluating existing theories of gravitation.
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Massa, Enrico. "Avogadro and Planck Constants, Two Pillars of the International System of Units." Physics 6, no. 2 (2024): 845–58. http://dx.doi.org/10.3390/physics6020052.
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The International System of Units (SI), the current form of the metric system and the world’s most used system of units, has been continuously updated and refined since the Metre Convention of 1875 to ensure that it remains up to date with the latest scientific and technological advances. The General Conference on Weights and Measures, at its 26th meeting in 2018, decided to adopt stipulated values of seven physical constants linked to seven measurement units (the second, meter, kilogram, ampere, kelvin, mole, and candela). This paper reviews the technologies developed, in intense and long-standing work, to determine the Avogadro and Planck constants, which are now integral to realising the kilogram.
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Carron, Julien, Mark Mirmelstein, and Antony Lewis. "CMB lensing from Planck PR4 maps." Journal of Cosmology and Astroparticle Physics 2022, no. 09 (2022): 039. http://dx.doi.org/10.1088/1475-7516/2022/09/039.
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Abstract We reconstruct the Cosmic Microwave Background (CMB) lensing potential on the latest Planck CMB PR4 (NPIPE) maps, which include slightly more data than the 2018 PR3 release, and implement quadratic estimators using more optimal filtering. We increase the reconstruction signal to noise by almost 20%, constraining the amplitude of the CMB-marginalized lensing power spectrum in units of the Planck 2018 best-fit to 1.004 ± 0.024 (68% limits), which is the tightest constraint on the CMB lensing power spectrum to date. For a base ΛCDM cosmology we find σ 8 Ωm 0.25 = 0.599 ± 0.016 from CMB lensing alone in combination with weak priors and element abundance observations. Combination with baryon acoustic oscillation data gives tight 68% constraints on individual ΛCDM parameters σ m = 0.814 ± 0.016, H 0 = 68.1+1.0 -1.1 km s-1 Mpc-1, Ωm = 0.313+0.014 -0.016. Planck polarized maps alone now constrain the lensing power to 7%.
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KISELEV, V. V., and S. A. TIMOFEEV. "THE SURFACE DENSITY OF HOLOGRAPHIC ENTROPY." Modern Physics Letters A 25, no. 26 (2010): 2223–30. http://dx.doi.org/10.1142/s0217732310033608.
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On the basis of postulates for the holographic description of gravity and the introduction of entropic force, for static sources we derive the universal law: the entropy of a holographic screen is equal to quarter of its area in the Planck system of units.
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VALEV, Dimitar. "Cosmological model free of singularity and inflation based on the large numbers hypothesis." Proceedings of the Romanian Academy, Series A: Mathematics, Physics, Technical Sciences, Information Science 24, no. 4 (2023): 329–38. http://dx.doi.org/10.59277/pra-ser.a.24.4.05.
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It is shown that the new precise formulation of the Large Number Hypothesis (LNH), relating by means of the large number N_0 = 5.73×10^60 the modern cosmological parameters (age, size, mass, average density, and minimum temperature of the universe) with the corresponding Planck units, allows to determine the time course of these cosmological parameters during the expansion. It was found that the dimensions and mass of the universe increase linearly with time from Planck time t = t_P to the present day, starting from Planck values and increasing N_0 = 5.73×10^60 times to now. The amazing result was found that for each discrete time step (beat) with a unit Planck time ∆t = t_P, the size of the universe increases by one Planck length l_P and its mass increases by one Planck mass m_P. It is shown that the average density of the universe decreases proportionally to the square of time, and starting from the Planck density ρ_P ~ 10^96 kg m-3 decreases N_0^2 = 3.28×10^121 times to 9.46×10^-27 kg m-3 in the current epoch. The minimum measurable temperature, which is equal to the Hawking temperature for the universe T_H decreases linearly with time 5.73×10^60 times, and starting from the Planck temperature T_P = 10^32 K, it falls to 1.75×10^-29 K at the present time. It is shown that the found time course of cosmological parameters and the Planck values of the size, mass, average density, and temperature of the universe at the initial moment of the expansion t = t_P follow from the requirement to preserve the Euclidean geometry of space throughout the time of the cosmological expansion. Therefore, the suggested cosmological model based on the new formulation of LNH is free of singularity because the size and density of the universe remain finite/Planckian in the initial moments of its emergence. Besides, this model conserves the flatness and homogeneity of the universe during cosmological expansion and does not need an inflationary epoch in the early universe.
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Gueorguiev, Vesselin, and Andre Maeder. "Revisiting the Cosmological Constant Problem within Quantum Cosmology." Universe 6, no. 8 (2020): 108. http://dx.doi.org/10.3390/universe6080108.
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A new perspective on the Cosmological Constant Problem (CCP) is proposed and discussed within the multiverse approach of Quantum Cosmology. It is assumed that each member of the ensemble of universes has a characteristic scale a that can be used as integration variable in the partition function. An averaged characteristic scale of the ensemble is estimated by using only members that satisfy the Einstein field equations. The averaged characteristic scale is compatible with the Planck length when considering an ensemble of solutions to the Einstein field equations with an effective cosmological constant. The multiverse ensemble is split in Planck-seed universes with vacuum energy density of order one; thus, Λ˜≈8π in Planck units and a-derivable universes. For a-derivable universe with a characteristic scale of the order of the observed Universe a≈8×1060, the cosmological constant Λ=Λ˜/a2 is in the range 10−121–10−122, which is close in magnitude to the observed value 10−123. We point out that the smallness of Λ can be viewed to be natural if its value is associated with the entropy of the Universe. This approach to the CCP reconciles the Planck-scale huge vacuum energy–density predicted by QFT considerations, as valid for Planck-seed universes, with the observed small value of the cosmological constant as relevant to an a-derivable universe as observed.
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Wang, Xijia. "New Discovery on Planck Units and Physical Dimension in Cosmic Continuum Theory." Journal of Modern Physics 09, no. 14 (2018): 2391–401. http://dx.doi.org/10.4236/jmp.2018.914153.
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Aghanim, N., Y. Akrami, M. Ashdown, et al. "Planck intermediate results." Astronomy & Astrophysics 607 (November 2017): A95. http://dx.doi.org/10.1051/0004-6361/201629504.
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The six parameters of the standard ΛCDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium τ, the baryon density ωb, the matter density ωm, the angular size of the sound horizon θ∗, the spectral index of the primordial power spectrum, ns, and Ase− 2τ (where As is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment ℓ < 800 in the Planck temperature power spectrum) and an all angular-scale data set (ℓ < 2500Planck temperature power spectrum), each with a prior on τ of 0.07 ± 0.02. We find that the shifts, in units of the 1σ expected dispersion for each parameter, are { Δτ,ΔAse− 2τ,Δns,Δωm,Δωb,Δθ∗ } = { −1.7,−2.2,1.2,−2.0,1.1,0.9 }, with a χ2 value of 8.0. We find that this χ2 value is exceeded in 15% of our simulated data sets, and that a parameter deviates by more than 2.2σ in 9% of simulated data sets, meaning that the shifts are not unusually large. Comparing ℓ < 800 instead to ℓ> 800, or splitting at a different multipole, yields similar results. We examined the ℓ < 800 model residuals in the ℓ> 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in ΛCDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is τ, which, at fixed Ase− 2τ, affects the ℓ> 800 temperature power spectrum solely through the associated change in As and the impact of that on the lensing potential power spectrum. We also ask, “what is it about the power spectrum at ℓ < 800 that leads to somewhat different best-fit parameters than come from the full ℓ range?” We find that if we discard the data at ℓ < 30, where there is a roughly 2σ downward fluctuation in power relative to the model that best fits the full ℓ range, the ℓ < 800 best-fit parameters shift significantly towards the ℓ < 2500 best-fit parameters. In contrast, including ℓ < 30, this previously noted “low-ℓ deficit” drives ns up and impacts parameters correlated with ns, such as ωm and H0. As expected, the ℓ < 30 data have a much greater impact on the ℓ < 800 best fit than on the ℓ < 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-ℓ residuals and the deficit in low-ℓ power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between PlanckTT data and two other CMB data sets, namely the Planck lensing reconstruction and the TT power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the ΛCDM model.
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Berbente, Corneliu, Sorin Berbente, and Marius Brebenel. "A possible new definition of the fundamental measure units." Journal of Engineering Sciences and Innovation 6, no. 1 (2021): 85–90. http://dx.doi.org/10.56958/jesi.2021.6.1.8.
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A new definition of the measure units in Physics by using the concept of cardinal number and by considering universal physical constants is proposed. Another idea is to start from the moment of the creation of the Universe (BIG BANG or better said BIG FLASH). n this way, along with the speed of light in vacuum CV, the Planck constant h and the total energy of the Universe, EU are introduced. As regards the measure unit for temperature, the Boltzmann constant kB is considered. For the electrical charge, the electron charge is taken as a constant. In this way the sustenability of evaluation of technical parameters is increased. For example, the lowest sustenability is for unitts like (feet;pounds) instead of (meters; kgs).
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KIM, Mun-Seog, Dong-Hun CHAE, and Kwang-Cheol LEE. "Quantum Metrology of Electrical Quantities and Mass." Physics and High Technology 30, no. 3 (2021): 17–25. http://dx.doi.org/10.3938/phit.30.008.
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The new International System of Units (SI) became effective on 20 May 2019. In the new SI, the complete system of units can be traced to seven fixed values of the fundamental constants, not to seven base units as in the old system. Electrical metrology has two important quantum mechanical foundations. Here, we introduce the basics and the metrological applications of the Josephson effect and the quantum Hall effect, which play key roles in linking electrical quantities to the fundamental constants, including the Planck constant h, the elementary charge e, and the transition frequency of cesium 133 ΔνCs. Finally, we discuss the redefinition of the kilogram as one of the important examples of electrical metrology based on quantum physics.
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Gaarder Haug, Espen. "The gravitational constant and the Planck units. A simplification of the quantum realm." Physics Essays 29, no. 4 (2016): 558–61. http://dx.doi.org/10.4006/0836-1398-29.4.558.
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Bordé, Christian J. "Base units of the SI, fundamental constants and modern quantum physics." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 363, no. 1834 (2005): 2177–201. http://dx.doi.org/10.1098/rsta.2005.1635.
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Over the past 40 years, a number of discoveries in quantum physics have completely transformed our vision of fundamental metrology. This revolution starts with the frequency stabilization of lasers using saturation spectroscopy and the redefinition of the metre by fixing the velocity of light c . Today, the trend is to redefine all SI base units from fundamental constants and we discuss strategies to achieve this goal. We first consider a kinematical frame, in which fundamental constants with a dimension, such as the speed of light c , the Planck constant h , the Boltzmann constant k B or the electron mass m e can be used to connect and redefine base units. The various interaction forces of nature are then introduced in a dynamical frame, where they are completely characterized by dimensionless coupling constants such as the fine structure constant α or its gravitational analogue α G . This point is discussed by rewriting the Maxwell and Dirac equations with new force fields and these coupling constants. We describe and stress the importance of various quantum effects leading to the advent of this new quantum metrology. In the second part of the paper, we present the status of the seven base units and the prospects of their possible redefinitions from fundamental constants in an experimental perspective. The two parts can be read independently and they point to these same conclusions concerning the redefinitions of base units. The concept of rest mass is directly related to the Compton frequency of a body, which is precisely what is measured by the watt balance. The conversion factor between mass and frequency is the Planck constant, which could therefore be fixed in a realistic and consistent new definition of the kilogram based on its Compton frequency. We discuss also how the Boltzmann constant could be better determined and fixed to replace the present definition of the kelvin.
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CARNEIRO, SAULO. "FROM DE SITTER TO DE SITTER: A NON-SINGULAR INFLATIONARY UNIVERSE DRIVEN BY VACUUM." International Journal of Modern Physics D 15, no. 12 (2006): 2241–47. http://dx.doi.org/10.1142/s0218271806009510.
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A semi-classical analysis of vacuum energy in the expanding space–time suggests that the cosmological term decays with time, with a concomitant matter production. For early times we find, in Planck units, Λ ≈ H4, where H is the Hubble parameter. The corresponding cosmological solution has no initial singularity, existing since an infinite past. During an infinitely long period we have a quasi-de Sitter, inflationary universe, with H ≈ 1. However, at a given time, the expansion undertakes a phase transition, with H and Λ decreasing to nearly zero in a few Planck times, producing a huge amount of radiation. On the other hand, the late-time scenario is similar to the standard model, with the radiation phase followed by a dust era, which tends asymptotically to a de Sitter universe, with vacuum dominating again.
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Żenczykowski, Piotr. "MOND and natural scales of distance and mass." Modern Physics Letters A 34, no. 37 (2019): 1950306. http://dx.doi.org/10.1142/s0217732319503061.
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We describe a MOND-related approach to natural scales of distance and mass, viewing it as a logical step following Planck’s modification of the Stoney system of units. The MOND-induced scales are not based on the strength of any physical interaction (electromagnetic, gravitational, or otherwise). Instead, they are specified by three physical constants of a general nature that define the scales of action, speed, and acceleration, i.e. [Formula: see text] — the Planck constant, [Formula: see text] — the speed of light and [Formula: see text] — the MOND acceleration constant. When the gravitational constant [Formula: see text] is added, two further distance scales (apart from the size of the Universe) appear: the Planck scale and a nanometer scale that fits the typical borderline between the classical and the quantum descriptions.
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Rovelli, Carlo. "Black Holes Have More States than Those Defined by the Bekenstein–Hawking Entropy: A Simple Argument." Universe 11, no. 1 (2024): 6. https://doi.org/10.3390/universe11010006.
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It is often assumed that the maximum number of independent states a black hole may contain is NBH=eSBH, where SBH=A/4 is the Bekenstein–Hawking entropy and A is the horizon area in Planck units. I present a simple and straightforward argument showing that the number of states that can be distinguished by local observers inside the hole must be greater than this number.
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CARNEIRO, SAULO. "ON THE VACUUM ENTROPY AND THE COSMOLOGICAL CONSTANT." International Journal of Modern Physics D 12, no. 09 (2003): 1669–73. http://dx.doi.org/10.1142/s0218271803004158.
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It is generally accepted that the entropy of an asymptotically de Sitter universe is bounded by the area, in Planck units, of the de Sitter horizon. Based on an analysis of the entropy associated to the vacuum quantum fluctuations, we suggest that the existence of such a holographic bound constitutes a possible explanation for the observed value of the cosmological constant, theoretically justifying a relation proposed 35 years ago by Zel'dovich.
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Valdés, Joaquín. "Explaining to different audiences the new definition and experimental realizations of the kilogram." Journal of Sensors and Sensor Systems 10, no. 1 (2021): 1–4. http://dx.doi.org/10.5194/jsss-10-1-2021.
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Abstract. Different options were discussed before reaching the final agreement on the new definitions of the SI units, effective from 20 May 2019, especially with regard to the kilogram, now defined in terms of the numerical value of the Planck constant (h). Replacing the artefact definition of the kilogram with a new one based on the mass of a particle, or the atomic mass constant (mu), would have been preferable for ease of understanding, among other reasons. In this paper we discuss some limitations of teaching to different audiences what a kilogram is in the redefined International System of Units (SI), including realizations of the new definition.
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Sanchez, Carlos. "Realizing the Kilogram from the Planck Constant: The Kibble Balance and the Electrical Units." IEEE Instrumentation & Measurement Magazine 24, no. 3 (2021): 5–10. http://dx.doi.org/10.1109/mim.2021.9436095.
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Wright, Jason T. "Planck frequencies as Schelling points in SETI." International Journal of Astrobiology 19, no. 6 (2020): 446–55. http://dx.doi.org/10.1017/s1473550420000221.
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AbstractIn SETI, when searching for ‘beacons’ – transmissions intended for us and meant to get our attention – one must guess the appropriate frequency to search by considering what frequencies would be universally obvious to other species. This is a well-known concept in game theory, where such solutions to a non-communicative cooperative game (such as a mutual search) are called ‘Schelling points’. It is noteworthy, therefore, that when developing his eponymous units, Planck called them ‘natural’ because they ‘remain meaningful for all times and also for extraterrestrial and non-human cultures’. Here, I apply Planck's suggestion in the context of Schelling points in SETI with a ‘Planck Frequency Comb’, constructed by multiplying the Planck energy by integer powers of the fine structure constant. This comb includes a small number of frequencies in regions of the electromagnetic spectrum where laser and radio SETI typically operates. Searches might proceed and individual teeth in the comb, or at many teeth at once, across the electromagnetic spectrum. Indeed, the latter strategy can be additionally justified by the transmitter's desire to signal at many frequencies at once, to improve the chances that the receiver will guess one of them correctly. There are many arbitrary and anthropocentric choices in this comb's construction, and indeed one can construct several different frequency combs with only minor and arbitrary modifications. This suggests that it may be fruitful to search for signals arriving in frequency combs of arbitrary spacing. And even though the frequencies suggested here are only debatably ‘better’ than others proposed, the addition of the Planck Frequency Comb to the list of ‘magic frequencies’ can only help searches for extraterrestrial beacons.
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Walker, Martin. "SU(2) × SU(2) Algebras and the Lorentz Group O(3,3)." Symmetry 12, no. 5 (2020): 817. http://dx.doi.org/10.3390/sym12050817.
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The Lie algebra of the Lorentz group O(3,3) admits two types of SU(2) × SU(2) subalgebras: a standard form based on spatial rotation generators and a second form based on temporal rotation generators. The units of measurement for the conserved quantity due to invariance under temporal rotations are investigated and found to be the same units of measure as the Planck constant. The breaking of time reversal symmetry is considered and found to affect the chiral properties of a temporal SU(2) × SU(2) algebra. Finally, the symmetry between algebras is explored and pairs of algebras are found to be related by SU(2) × U(1) symmetry, while a group of three algebras are related by SO(4) symmetry.
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Timkov, Valery F. "A METHOD FOR EMPIRICAL ESTIMATION OF PLANCK’S LENGTH, MASS, AND TIME THROUGH THE CHARACTERISTICS OF AN ELECTRON. IMPROVING THE ACCURACY OF SOME PHYSICAL CONSTANTS." Key title: Zbìrnik naukovih pracʹ Odesʹkoï deržavnoï akademìï tehnìčnogo regulûvannâ ta âkostì, no. 1(24) (2024): 19–28. http://dx.doi.org/10.32684/2412-5288-2024-1-24-19-28.
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A method for empirical estimation of Planck's length, mass, and time is proposed, which is based on the characteristics of the electron, Avogadro, and Euler numbers, and the fine structure constant. Basic physical constants can be expressed in terms of Planck's length, mass, and time. The disadvantage of this method is that Planck's elementary particle does not exist in nature. Planck's particle is presented in a hypothetical, virtual form, its characteristics are theoretically calculated through the reduced Planck's constant, Newton's gravitation constant, and the constant speed of light in a vacuum, and the accuracy of these characteristics is low. This is due to the low accuracy of the Newtonian constant of gravity. This shortcoming can be eliminated if the characteristics of the hypothetical Planck particle are associated with a real elementary particle, for example, with an electron, and through its characteristics with the characteristics of leptons and baryons. Since the characteristics of leptons and baryons are determined experimentally and are among the most accurate, for example, for a proton now is 11 decimal places, establishing a connection with them of a hypothetical Planck particle will increase the accuracy of the values: of Planck's length, mass and time, of Planck constant, of elementary electric charge, of the Newtonian gravitational constant, of electron mass, of Planck temperature up to the accuracy level of a proton. As is known, the 26th General Conference on Weights and Measures decided to define one of the basic SI units of measurement through physical constants. In particular, with this solution, the kilogram is now defined in terms of Planck's constant, and the ampere is now determined in terms of the value of the elementary electric charge. Accordingly, with increasing accuracy of the values of Planck's constant and elementary electric charge, the accuracy of the values of a kilogram and Ampere will increase.
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Nikolayevich Sukhanov, Vladimir. "Equivalence of electric charge and energy." International Journal of Physical Research 12, no. 2 (2024): 36–44. http://dx.doi.org/10.14419/bhmxn335.
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The equivalence of electric charge and energy is the principle that everything that has an electric charge has an equivalent amount of energy and vice versa. Main methods used: conversion of natural units, algebra, analogy. The equivalence of electric charge and energy, despite the wide use in describing the principles of physics and astrophysics, has not yet been formulated. In this work, the formula for the equivalence of electric charge and energy is presented. This is done on the basis of known measurement systems, parameters and principles of physics. Five examples (Stoney units, Planck units, Newton's law of universal gravitation, Coulomb's law and Ampere's law) of the algebraic notation of this principle show its universality. Five examples should justify the universality of the new principle and its use in physics, astrophysics and technology. New physical Units are proposed for mass and electric charge has been proposed, each of which is suitable for measuring both mass and electric charge. The paper gives perspectives of using the proposed equivalence: starting calculation of mass excess, refinement of orbits of celestial, and Einstein field equation.
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Prabhu, K., S. Raghunathan, M. Millea та ін. "Testing the ΛCDM Cosmological Model with Forthcoming Measurements of the Cosmic Microwave Background with SPT-3G". Astrophysical Journal 973, № 1 (2024): 4. http://dx.doi.org/10.3847/1538-4357/ad5ff1.
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Abstract We forecast constraints on cosmological parameters enabled by three surveys conducted with SPT-3G, the third-generation camera on the South Pole Telescope. The surveys cover separate regions of 1500, 2650, and 6000 deg2 to different depths, in total observing 25% of the sky. These regions will be measured to white noise levels of roughly 2.5, 9, and 12 μ K -armin, respectively, in cosmic microwave background (CMB) temperature units at 150 GHz by the end of 2024. The survey also includes measurements at 95 and 220 GHz, which have noise levels a factor of ∼1.2 and 3.5 times higher than 150 GHz, respectively, with each band having a polarization noise level ∼ 2 times higher than the temperature noise. We use a novel approach to obtain the covariance matrices for jointly and optimally estimated gravitational lensing potential band powers and unlensed CMB temperature and polarization band powers. We demonstrate the ability to test the ΛCDM model via the consistency of cosmological parameters constrained independently from SPT-3G and Planck data, and consider the improvement in constraints on ΛCDM extension parameters from a joint analysis of SPT-3G and Planck data. The ΛCDM cosmological parameters are typically constrained with uncertainties up to ∼2 times smaller with SPT-3G data, compared to Planck, with the two data sets measuring significantly different angular scales and polarization levels, providing additional tests of the standard cosmological model.
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Zak, Michail. "From Collective Mind to Communication." Complex Systems 14, no. 4 (2024): 335–61. http://dx.doi.org/10.25088/complexsystems.14.4.335.
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"Collective mind" is introduced as a set of simple intelligent units (say, neurons, or interacting agents) that can communicate by exchanging information without explicit global control. Incomplete information is compensated for by a sequence of random guesses symmetrically distributed around expectations with prescribed variances. Both the expectations and variances are the invariants characterizing the whole class of agents. These invariants are stored as parameters of the collective mind, while they contribute to dynamical formalism of the agents' evolution, and in particular, to the reflective chains of their nested abstract images of the selves and nonselves. The proposed model consists of the system of stochastic differential equations in the Langevin form to represent motor dynamics, and the corresponding Fokker-Planck equation to represent mental dynamics. The main departure of this model from newtonian and statistical physics is due to feedback from the mental to the motor dynamics, which makes the Fokker-Planck equation nonlinear. Interpretations of this model from mathematical, physical, biological, and psychological viewpoints are discussed. The model is illustrated by the dynamics of a dialog.
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Mykhailenko, Viacheslav, and Pavol Bobik. "Statistical Error for Cosmic Rays Modulation Evaluated by SDE Backward in Time Method for 1D Model." Fluids 7, no. 2 (2022): 46. http://dx.doi.org/10.3390/fluids7020046.
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The propagation of cosmic rays through the heliosphere has been solved for more than half a century by stochastic methods based on Ito’s lemma. This work presents the estimation of statistical error of solution of Fokker–Planck equation by the 1D backward in time stochastic differential equations method. The error dependence on simulation statistics and energy is presented for different combinations of input parameters. The 1% precision criterion in mean value units of intensity standard deviation is defined as a function of solar wind velocity and diffusion coefficient value.
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Davis, R. S. "The role of the international prototype of the kilogram after redefinition of the International System of Units." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1953 (2011): 3975–92. http://dx.doi.org/10.1098/rsta.2011.0181.
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Since 1889, the international prototype of the kilogram has served to define the unit of mass in what is now known as the International System of Units (SI). This definition, which continues to serve mass metrology well, is an anachronism for twenty-first century physics. Indeed, the kilogram will no doubt be redefined in terms of a physical constant, such as the Planck constant. As a practical matter, linking the quantum world to the macroscopic world of mass metrology has, and remains, challenging although great progress has been made. The international prototype or, more likely, a modern ensemble of reference standards, may yet have a role to play for some time after redefinition, as described in this paper.
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THOMAS, MATTHIEU. "Kilogram and new SI definitions." High Temperatures-High Pressures 48, no. 3 (2020): 193–205. http://dx.doi.org/10.32908/hthp.v48.789.
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The seven base units of the SI will be defined on May 20, 2019 by reference to fixed and exact values of defining constants. In particular, the kilogram will be defined from the Planck constant h, allowing weaknesses of the previous artefact definition to be lift up. The Kibble balance is one of the methods to realize a macroscopic mass from h: LNE has developed such a balance which is described. This balance has allowed LNE to contribute to the latest adjustment of the h value, and will be used to realize the mass unit in France.
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Wang, Jin. "New SI and precision measurements: an interview with Tianchu Li." National Science Review 7, no. 12 (2020): 1837–40. http://dx.doi.org/10.1093/nsr/nwz211.
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Abstract On 13–16 November 2018, the 26th General Conference of Weights and Measures (CGPM) was held in Paris. The conference adopted Resolution A on ‘Revision of the International System of Units (SI).’ According to Resolution A: four of the SI basic units, namely kilograms, amps, kelvin and mole, are defined by the Planck constant h, the basic charge constant e, the Boltzmann constant k and the Avogadro constant NA, respectively. This establishes the basic quantities and units in SI on a series of constants. The new SI was officially launched on 20 May 2019. This is the most significant change and a milestone in the history of metrology since the Metre Convention was signed in 20 May 1875. Professor Tianchu Li, an academician of the Chinese Academy of Engineering, has been working on time and frequency standards for 37 years. In this interview, Prof. Li reviews the quantization and constant evolutions of the second and meter, and introduces the redefinitions of ampere, kelvin, kilogram and mole, and their significance for precision measurements.
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Nikolayevich Sukhanov, Vladimir. "Space time energy equivalence." International Journal of Physical Research 12, no. 1 (2024): 10–23. http://dx.doi.org/10.14419/n7tgaw97.
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Space–time–energy equivalence is the principle that everything that has space and time (in the presence of a constant force with an impact point) has an equivalent amount of energy, and vice versa. This equivalence is widespread in physics and astrophysics. Five examples (Stoney units, Planck units, Newton's law and Interaction of light rays, standard gravitational parameter and Coulomb's law) of the algebraic notation of this principle show its universality. Five examples (repetitions) of the same principle should justify the universality of the new principle and its use in physics and astrophysics. The proposed equivalence reveals the functional relationship between physical constants: Planck's constant, electric charge of an electron, vacuum permittivity and vacuum permeability. The realization of this equivalence will allow, through deepening the understanding of the nature of space–time, to take a fresh look at physics, when describing natural laws and principles.
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Gupta, Rajendra P. "Varying Physical Constants, Astrometric Anomalies, Redshift and Hubble Units." Galaxies 7, no. 2 (2019): 55. http://dx.doi.org/10.3390/galaxies7020055.
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We have developed a cosmological model by allowing the speed of light c, gravitational constant G and cosmological constant Λ in the Einstein filed equation to vary in time, and solved them for Robertson-Walker metric. Assuming the universe is flat and matter dominant at present, we obtain a simple model that can fit the supernovae 1a data with a single parameter almost as well as the standard ΛCDM model with two parameters, and which has the predictive capability superior to the latter. The model, together with the null results for the variation of G from the analysis of lunar laser ranging data determines that at the current time G and c both increase as dG/dt = 5.4GH0 and dc/dt = 1.8cH0 with H0 as the Hubble constant, and Λ decreases as dΛ/dt = −1.2ΛH0. This variation of G and c is all what is needed to account for the Pioneer anomaly, the anomalous secular increase of the moon eccentricity, and the anomalous secular increase of the astronomical unit. We also show that the Planck’s constant ħ increases as dħ/dt = 1.8ħH0 and the ratio D of any Hubble unit to the corresponding Planck unit increases as dD/dt = 1.5DH0. We have shown that it is essential to consider the variation of all the physical constants that may be involved directly or indirectly in a measurement rather than only the one whose variation is of interest.
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Nikolayevich Sukhanov, Vladimir. "Equivalence of magnetic flux and energy." International Journal of Physical Research 12, no. 2 (2024): 74–89. http://dx.doi.org/10.14419/cz021356.
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Magnetic flux and energy equivalence is the principle that everything that has magnetic flux has an equivalent amount of energy, and vice versa. The main methods used: transformation of natural units, algebra, analogy. The equivalence of magnetic flux and energy, despite its widespread use in describing the principles of physics, has not yet been formulated. This paper presents the formula for this equivalence. This is done based on known measurement systems, parameters and principles of physics. Five examples (Stoney units, Planck units, standard gravitational parameter, Lorentz force, and Ampere force) of the algebraic representation of this principle show its universality. Five examples should justify the universality of the new principle and its use in physics and astrophysics. Using the equivalence of magnetic flux and energy, new physical units of mass and magnetic flux are proposed, each of which is suitable for measuring both mass and magnetic flux. Natural values of electric current and voltage, linear density of electric capacitance and inductance, linear density of magnetic flux, linear density of electric charge, as well as natural units of electric voltage and current, electrical resistance, magnetic flux, electrical capacitance and inductance are also described. The article presents the Einstein field equation (additional magnetic stress–energy–momentum tensor) and a standard astrophysical parameter for refining the orbits of celestial bodies.
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Ballantine, Kyle E., John F. Donegan, and Paul R. Eastham. "There are many ways to spin a photon: Half-quantization of a total optical angular momentum." Science Advances 2, no. 4 (2016): e1501748. http://dx.doi.org/10.1126/sciadv.1501748.
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The angular momentum of light plays an important role in many areas, from optical trapping to quantum information. In the usual three-dimensional setting, the angular momentum quantum numbers of the photon are integers, in units of the Planck constantħ. We show that, in reduced dimensions, photons can have a half-integer total angular momentum. We identify a new form of total angular momentum, carried by beams of light, comprising an unequal mixture of spin and orbital contributions. We demonstrate the half-integer quantization of this total angular momentum using noise measurements. We conclude that for light, as is known for electrons, reduced dimensionality allows new forms of quantization.
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Mills, Ian M., Peter J. Mohr, Terry J. Quinn, Barry N. Taylor, and Edwin R. Williams. "Adapting the International System of Units to the twenty-first century." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1953 (2011): 3907–24. http://dx.doi.org/10.1098/rsta.2011.0180.
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We review the proposal of the International Committee for Weights and Measures (Comité International des Poids et Mesures, CIPM), currently being considered by the General Conference on Weights and Measures (Conférences Générales des Poids et Mesures, CGPM), to revise the International System of Units (Le Système International d'Unitès, SI). The proposal includes new definitions for four of the seven base units of the SI, and a new form of words to present the definitions of all the units. The objective of the proposed changes is to adopt definitions referenced to constants of nature, taken in the widest sense, so that the definitions may be based on what are believed to be true invariants. In particular, whereas in the current SI the kilogram, ampere, kelvin and mole are linked to exact numerical values of the mass of the international prototype of the kilogram, the magnetic constant (permeability of vacuum), the triple-point temperature of water and the molar mass of carbon-12, respectively, in the new SI these units are linked to exact numerical values of the Planck constant, the elementary charge, the Boltzmann constant and the Avogadro constant, respectively. The new wording used expresses the definitions in a simple and unambiguous manner without the need for the distinction between base and derived units. The importance of relations among the fundamental constants to the definitions, and the importance of establishing a mise en pratique for the realization of each definition, are also discussed.
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Hart, Luke, and Jens Chluba. "Updated fundamental constant constraints from Planck 2018 data and possible relations to the Hubble tension." Monthly Notices of the Royal Astronomical Society 493, no. 3 (2020): 3255–63. http://dx.doi.org/10.1093/mnras/staa412.
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ABSTRACT We present updated constraints on the variation of the fine structure constant, αEM, and effective electron rest mass, me, during the cosmological recombination era. These two fundamental constants directly affect the ionization history at redshift z ≃ 1100 and, thus, modify the temperature and polarization anisotropies of the cosmic microwave background (CMB) measured precisely with Planck . The constraints on αEM tighten slightly due to improved Planck 2018 polarization data but otherwise remain similar to previous CMB analysis. However, a comparison with the 2015 constraints reveals a mildly discordant behaviour for me, which from CMB data alone is found below its local value. Adding baryon acoustic oscillation data brings me back to the fiducial value, $m_{\rm e}=(1.0078\pm 0.0067)\, m_{\rm e,0}$, and also drives the Hubble parameter to H0 = 69.1 ± 1.2(in units of ${\rm km \, s^{-1} \, Mpc^{-1} }$). Further adding supernova data yields $m_{\rm e}=(1.0190\pm 0.0055)\, m_{\rm e,0}$ with H0 = 71.24 ± 0.96. We perform several comparative analyses using the latest cosmological recombination calculations to further understand the various effects. Our results indicate that a single-parameter extension allowing a slightly increased value of me (≃3.5σ above me, 0) could play a role in the Hubble tension.
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Kaptay, G. "On the five base quantities of nature and SI (The International System of Units)." Journal of Mining and Metallurgy, Section B: Metallurgy 47, no. 2 (2011): 241–46. http://dx.doi.org/10.2298/jmmb110620015k.
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It is shown here that five base quantities (and the corresponding five base units) of nature are sufficient to define all derived quantities (and their units) and to describe all natural phenomena. The base quantities (and their base units) are: length (m), mass (kg), time (s), temperature (K) and electric charge (C). The amount of substance (mole) is not taken as a base quantity of nature and the Avogadro constant is not considered as a fundamental constant of nature, as they are both based on an arbitrary definition (due to the arbitrary value of 0.012 kg for the mass of 1 mole of C-12 isotope). Therefore, the amount of substance (mole) is moved from the list of base quantities to the category of the supplementary units (to be re-created after its abrogation in 1995). Based on its definition, the luminous intensity (cd) is not a base quantity (unit), therefore it is moved to the list of derived quantities (units). The ampere and coulomb are exchanged by places in the list of base and derived units, as ampere is a speed of coulombs (but SI defines meter, not its speed as a base unit). The five base quantities are re-defined in this paper by connecting them to five fundamental constants of nature (the most accurately known frequency of the hydrogen atom, the speed of light, the Planck constant, the Boltzmann constant and the elementary charge) with their numerical values fixed in accordance with their CODATA 2006 values (to be improved by further experiments).