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This work presents a new method called Dimensionless Fluctuation Balance (DFB), which makes it possible to obtain distributions as solutions of Partial Differential Equations (PDEs). In the first case study, DFB was applied to obtain the Boltzmann PDE, whose solution is a distribution for Boltzmann gas. Following, the Planck photon gas in the Radiation Law, Fermi–Dirac, and Bose–Einstein distributions were also verified as solutions to the Boltzmann PDE. The first case study demonstrates the importance of the Boltzmann PDE and the DFB method, both introduced in this paper. In the second case study, DFB is applied to thermal and entropy energies, naturally resulting in a PDE of Boltzmann's entropy law. Finally, in the third case study, quantum effects were considered. So, when applying DFB with Heisenberg uncertainty relations, a Schrödinger case PDE for free particles and its solution were obtained. This allows for the determination of operators linked to Hamiltonian formalism, which is one way to obtain the Schrödinger equation. These results suggest a wide range of applications for this methodology, including Statistical Physics, Schrödinger's Quantum Mechanics, Thin Films, New Materials Modeling, and Theoretical Physics. [ABSTRACT FROM AUTHOR]

Abstract This work presents a new method called Dimensionless Fluctuation Balance (DFB), which makes it possible to obtain distributions as solutions of Partial Differential Equations (PDEs). In the first case study, DFB was applied to obtain the Boltzmann PDE, whose solution is a distribution for Boltzmann gas. Following, the Planck photon gas in the Radiation Law, Fermi–Dirac, and Bose–Einstein distributions were also verified as solutions to the Boltzmann PDE. The first case study demonstrates the importance of the Boltzmann PDE and the DFB method, both introduced in this paper. In the second case study, DFB is applied to thermal and entropy energies, naturally resulting in a PDE of Boltzmann’s entropy law. Finally, in the third case study, quantum effects were considered. So, when applying DFB with Heisenberg uncertainty relations, a Schrödinger case PDE for free particles and its solution were obtained. This allows for the determination of operators linked to Hamiltonian formalism, which is one way to obtain the Schrödinger equation. These results suggest a wide range of applications for this methodology, including Statistical Physics, Schrödinger’s Quantum Mechanics, Thin Films, New Materials Modeling, and Theoretical Physics.

Rightly recognized as a great scientific achievement of physics of the XX century, the special theory of relativity (SRT), however, turned out to be erroneous, because at that time there was no experimental knowledge necessary for its creation, which had to be replaced by postulates. But not everything was guessed. And that's only natural. All new theories are always later finalized and corrected. But the SRT had a different fate. It was canonized, as in its truth could not be doubted50, it could not be corrected, and everything that was written in it had to be unshakably believed. Therefore, its numerous subsequent experimental corrections and refutations were not and still are not taken into account. As a result, it remained uncorrected. It is in this form that SRT is now studied in all physics textbooks, according to which it is taught even at the most prestigious universities. However, a corrected version of SRT has already been created, in which instead of the in-correct principle of non-exceeding the speed of light, the experimentally proven principle of phys-ical reality of imaginary numbers, which refuted this postulate, is used. And from relativistic for-mulas of the corrected version of SRT follows the existence of numerous mutually invisible parallel universes. The corrected version of SRT has allowed to solve many unsolved in the noncorrected version of SRT problems. In the corrected version of SRT also it is explained that these invisible universes about which it is spoken in all religions, and are invisible afterlife world in which Gods and souls of dead dwell. [ABSTRACT FROM AUTHOR]

A linear pyrometer is used to realize the International Temperature Scale of 1990 (ITS-90) for temperature ranges above 961.78 °C in most National Metrology Institute (NMI) radiation thermometry labs. The different components of the linear pyrometer system working together to measure temperature may exhibit some errors which should be accounted for. The errors can be characterized by several equipment parameters that should be measured before the radiation thermometer is used to realize ITS-90 temperatures. Relative spectral responsivity (s), size of source effect (SSE), gain ratio (GR), non-linearity (NL), distance effect (DE), temperature coefficient and zero drift are all major equipment parameters that characterize the efficiency of a linear pyrometer in realizing ITS-90. In this work, an attempt was made to describe and demonstrate these major parameters by using actual measured characterization results of a linear pyrometer. Uncertainty contributions from some of the parameters considered in scale realizations was also demonstrated using the measurement results. [ABSTRACT FROM AUTHOR]

Ilse Rosenthal-Schneider (1891–1990), a refugee immigrant to Australia in 1938, was a student of Nobel Prize-winning physicists, Einstein, Planck, and von Laue. She combined a background in physics, especially relativity theory, with a philosophical focus on the nature and possibilities of knowledge. As well as working at the University of Sydney to teach science students how to recognise philosophical issues in their subjects, she drove a major outreach programme to regional towns in New South Wales, where she was fêted by her audiences as a highly accomplished science communicator. Her best-known book, published in 1980, examined her interactions with Einstein, Planck, and von Laue by expanding on how all of them understood the relationship between science and philosophy. Rosenthal-Schneider never achieved a great deal of recognition, due in part to the limited opportunities for women of her era, but also due to her insistence on bridging disciplines and engaging in a scientific and philosophical dialogue beyond academia. We will show how Rosenthal-Schneider explored the borderlands of science and philosophy throughout her life, as she argued for the relevance of philosophical questions to practising scientists and non-academic publics in Australia. Ilse Rosenthal-Schneider (1891–1990), a refugee immigrant to Australia in 1938, was a student of Nobel Prize-winning physicists, Einstein, Planck, and von Laue. She combined a background in physics with a philosophical focus. Her intellectual life was spent in the borderlands between science and philosophy, but also science and society, as she engaged in public outreach with considerable success in the regional towns of NSW. Credit: Wayne State University Press (out of copyright). [ABSTRACT FROM AUTHOR]

The principle of conservation of energy tells us that 'energy can neither be created nor destroyed but only transformed'. The validity of the principle is without question. The problem is the concept. Contemporary physicists have asserted that we do not know what energy is. We find, however, 19th century physicists, contemporary physicists and historians of science who converge on the point: Mayer and Joule discovered energy. Therefore, we do not know what energy is, but we know these authors discovered it. What did they then discover? What can we learn from this with regard to the energy concept problem? To deal with this issue, I will distinguish between what the authors did experimentally and what they said about the phenomena. This method of analysis makes the difference in relation to historical works on the subject. In a second step, I will consider the introduction of the energy concept, which is from 1850s, and the reification of the energy in 1880s. Finally, I will address the energy conservation principle and the concept of energy conveyed by this principle in contemporary textbooks. As we shall see, the conservation of a magnitude that we call energy nowadays was discovered by Mayer and Joule; an indestructible and transformable entity was not. Adopting the original conservation principle would be enough to avoid the energy concept problem. [ABSTRACT FROM AUTHOR]

Zusammenfassung Wird der kosmische Mikrowellenhintergrund CMB (Cosmic Microwave Background) von vielen Vordergründen befreit, offenbart er Temperaturschwankungen von einigen zehn Mikrokelvin, die den Zustand des Universums 400 000 Jahre nach dem Urknall widerspiegeln. Die statistische Analyse dieser Schwankungen zeigt charakteristische Strukturen, aus denen sechs kosmologische Parameter direkt bestimmt werden können. Durch die Kombination des CMB mit anderen kosmologischen Beobachtungen können weitere Parameter indirekt abgeleitet werden. Dadurch wurde das kosmologische Standardmodell beeindruckend bestätigt, aber es bleiben auch bis heute ungeklärte Widersprüche bestehen. [ABSTRACT FROM AUTHOR]

The concept of indistinguishable particles in quantum theory is fundamental to questions of ontology. All ordinary matter is made of electrons, protons, neutrons, and photons and they are all indistinguishable particles. Yet the concept itself has proved elusive, in part because of the interpretational difficulties that afflict quantum theory quite generally, and in part because the concept was so central to the discovery of the quantum itself, by Planck in 1900; it came encumbered with revolution. I offer a deflationary reading of the concept 'indistinguishable' that is identical to Gibbs' concept 'generic phase', save that it is defined for state spaces with only finitely -many states of bounded volume and energy (finitely-many orthogonal states, in quantum mechanics). That, and that alone, makes for the difference between the quantum and Gibbsean concepts of indistinguishability. This claim is heretical on several counts, but here we consider only the content of the claim itself, and its bearing on the early history of quantum theory rather than in relation to contemporary debates about particle indistinguishability and permutation symmetry. It powerfully illuminates that history. • Indistinguishable particles have the same state-independent properties, but may differ wildly in state-dependent properties. • Gibbs' concept of indistinguishability is the same as that in quantum theory, when carried over to a finite state space. • Not even classical indistinguishable particles are statistically independent, in Einstein's sense. • Einstein's 1905 light quantum argument assumed rather than derived statistical independence. • The statistical dependencies of indistinguishable particles can be explained classically, without appeal to entanglement. [ABSTRACT FROM AUTHOR]

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The present age, which can be called the Information Age, has a core technology constituted by bits transported by photons. Both concepts, bit and photon, originated in the past century: the concept of photon was introduced by Planck in 1900 when he advanced the solution of the blackbody spectrum, and bit is a term first used by Shannon in 1948 when he introduced the theorems that founded information theory. The connection between Planck and Shannon is not immediately apparent; nor is it obvious that they derived their basic results from the concept of entropy. Examination of other important scientists can shed light on Planck's and Shannon's work in these respects. Darwin and Fowler, who in 1922 published a couple of papers where they reinterpreted Planck's results, pointed out the centrality of the partition function to statistical mechanics and thermodynamics. The same roots have been more recently reconsidered by Jaynes, who extended the considerations advanced by Darwin and Fowler to information theory. This paper investigates how the concept of entropy was propagated in the past century in order to show how a simple intuition, born in the 1824 during the first industrial revolution in the mind of the young French engineer Carnot, is literally still enlightening the fourth industrial revolution and probably will continue to do so in the coming century. [ABSTRACT FROM AUTHOR]

Context: Bolometers are high sensitivity detector commonly used in Infrared astronomy. The HFI instrument of the Planck satellite makes extensive use of them, but after the satellite launch two electronic related problems revealed critical. First an unexpected excess response of detectors at low optical excitation frequency for ν < 1 Hz, and secondly the Analog To digital Converter (ADC) component had been insufficiently characterized on-ground. These two problems require an exquisite knowledge of detector response. However bolometers have highly nonlinear characteristics, coming from their electrical and thermal coupling making them very difficult to model. Goal: We present a method to build the analytical transfer function in frequency domain which describe the voltage response of an Alternative Current (AC) biased bolometer to optical excitation, based on the standard bolometer model. This model is built using the setup of the Planck/HFI instrument and offers the major improvement of being based on a physical model rather than the currently in use had-hoc model based on Direct Current (DC) bolometer theory. Method: The analytical transfer function expression will be presented in matrix form. For this purpose, we build linearized versions of the bolometer electro thermal equilibrium. A custom description of signals in frequency is used to solve the problem with linear algebra. The model performances is validated using time domain simulations. Results: The provided expression is suitable for calibration and data processing. It can also be used to provide constraints for fitting optical transfer function using real data from steady state electronic response and optical response. The accurate description of electronic response can also be used to improve the ADC nonlinearity correction for quickly varying optical signals. [ABSTRACT FROM AUTHOR]

Three important sets of papers, written in the beginning of the 20th century, critically influenced and shaped the development and interpretation of quantum theory as currently known. In 1901, Planck demonstrated the necessity of introducing quantized amounts of energy in order to successfully derive an equation for the energy distribution in the black-body spectrum. In 1905, Einstein then introduced his famous hypothesis of "indivisible light quanta" in order to explain the photo-electric effect. He used this concept in 1917 to derive the black-body spectrum in a way distinctly different from Planck. Many years later, in 1923, Bose showed how one can derive Planck's result without resorting to the classically derived displacement law by Wien. In this paper, we review the essential points of these important historical papers and critically discuss their assumptions, interpretations, and domain of applicability of the results in light of our current state of knowledge. By focusing on the physical processes behind the results derived by these authors, we build upon their valuable work. We point out some inconsistencies perpetuated today, which result in apparent paradoxes and strange interpretations of physical processes. Constantly questioning and updating our theories and replacing historical inconsistencies with modern, physical process based knowledge, as we will demonstrate in this paper, result in a more logically sound science. In particular, this paper discusses (i) why the black-body spectrum does not provide any evidence for the quantization of propagating light waves and (ii) that it does not imply interaction between light waves without the mediation of material particles. We demonstrate an alternative derivation of Planck's equation which makes these ideas more explicit. [ABSTRACT FROM AUTHOR]

The Planck mission prime objective was a very accurate and complete measurement of the temperature anisotropies of the Cosmic Microwave Background (CMB). Cosmological results from the intensity data of the nominal mission of a duration of 15 months were disclosed on 21 March 2013. Fortunately, the satellite kept acquiring data for at least twice longer, and we announced in February 2015 new results based on all the data acquired, both in temperature and polarization. I provide a short overview of the latest data and findings of most interest for inflation, as a basis for the other contributions to this volume. This overview is entirely based on the published or submitted works of the Planck collaboration. [ABSTRACT FROM AUTHOR]

The present age, which can be called the Information Age, has a core technology constituted by bits transported by photons. Both concepts, bit and photon, originated in the past century: the concept of photon was introduced by Planck in 1900 when he advanced the solution of the blackbody spectrum, and bit is a term first used by Shannon in 1948 when he introduced the theorems that founded information theory. The connection between Planck and Shannon is not immediately apparent; nor is it obvious that they derived their basic results from the concept of entropy. Examination of other important scientists can shed light on Planck’s and Shannon’s work in these respects. Darwin and Fowler, who in 1922 published a couple of papers where they reinterpreted Planck’s results, pointed out the centrality of the partition function to statistical mechanics and thermodynamics. The same roots have been more recently reconsidered by Jaynes, who extended the considerations advanced by Darwin and Fowler to information theory. This paper investigates how the concept of entropy was propagated in the past century in order to show how a simple intuition, born in the 1824 during the first industrial revolution in the mind of the young French engineer Carnot, is literally still enlightening the fourth industrial revolution and probably will continue to do so in the coming century.

The recent detection of degree scale B-mode polarization in the Cosmic Microwave Background (CMB) by the BICEP2 experiment implies that the inflationary ratio of tensor-to-scalar fluctuations is r = 0.2-0.05'+0.07 which has opened a new window in the cosmological investigation. In this regard, we propose a study of the tree level potential inflation in the framework of the Randall-Sundrum type-2 braneworld model. We focus on three branches of the potential, where we evaluate some values of brane tension λ. We discuss how the various inflationary perturbation parameters can be compatible with recent Planck and BICEP2 observations. [ABSTRACT FROM AUTHOR]

In this paper we study a new inflation potential proposed in Belhaj et al. (Int J Mod Phys D 17:911-920, ), in the presence of a scalar field which interacts nonminimally with gravity. We present new constraints on the scalar spectral index $$n_{s}$$ , the tensor-to-scalar ratio $$r$$ and running of the spectral index $$\frac{dn_{s}}{ d\ln (k)}$$ from the recent data obtained by the Planck and BICEP2 experiment. The slow-roll parameters are reformulated in the case of a nonminimally coupled scalar field. We show that for parameter spaces of the models, inflation can occur at field values far below the four-dimensional Planck scale. We show also that for small and positive values of the nonminimal coupling $$\xi $$ , the observational consequences of this model are in perfect compatibility with the latest observations data especially for $$N=50$$ . [ABSTRACT FROM AUTHOR]

Once that the focal plane of the HFI instrument of the Planck mission (launched in May 2009) has reached operational temperature, we have observed the thermal effect of cosmic ray interaction with the Planck satellite, located at Lagrangian point L2. When a particle hits a component of the bolometers (e.g.: thermometer, grid or wafer) composing the focal plane of HFI, a thermal spike (called glitch), due to deposited energy, is observed. Processing these data revealed another effect due to high energy cosmic ray particle showers: High Coincidence Events (HCE), composed of glitches occurring coincidentally in many detectors and with a temperature increase from nK to $$\upmu $$ K after the shower. A flux of about 100 HCE per hour has been calculated. Two types of HCE have been detected: fast and slow. For the first type, the untouched bolometers reach the same temperature as the touched ones in a few seconds which can be explained by a storage of the deposited energy in the stainless steel focal plane. The second type of HCE is not fully understood yet. These effects might be explained by extra conduction from the helium released from cryogenic surfaces, creating a temporary thermal link between the different stages of the HFI. [ABSTRACT FROM AUTHOR]

Despite the praise his writing garnered during his lifetime, e.g., from readers such as Einstein and de Broglie, Emile Meyerson has been largely forgotten. The rich tradition of French epistemologie has recently been taken up in some Anglo-American scholarship, but Meyerson--who popularized the term epistemologie through his historical method of analyzing science, and criticized positivism long before Quine and Kuhn--remains overlooked. If Meyerson is remembered at all, it is as a historian of classical science. This paper attempts to rectify both states of affairs by explicating one of Meyerson's last and untranslated works, RÉel et dÉterminisme dans la thÉorie quantique, an opuscule on quantum physics. I provide an overview of Meyerson's philosophy, his critique of Max Planck's interpretation of quantum physics, and then outline and evaluate Meyerson's neo-Kantian alternative. I then compare and contrast this interpretation with Cassirer's neo-Kantian program. Finally I show that, while Meyerson believes the revolutionary new physics requires "profoundly" modifying our conception of reality, ultimately, he thinks, it secures the legitimacy of his thesis: that science seeks explanations in the form of what he calls "identification." 1 hope my research will enable a more general and systematic engagement with Meyerson's work, especially with a view to assessing its viability as a philosophical method today. [ABSTRACT FROM AUTHOR]

Una revisión del concepto de partícula elemental indivisible, como constituyente básico de la materia, nos conduce a contradicciones con los principios de las teorías físicas convencionales. Este concepto primitivo sería la causa del retraso, entorpecimiento y desviación de la labor fundamentalista del físico en la Tierra.

The Herschel Space Observatory and the Planck satellite are providing radical improvements to our knowledge of the spectral energy distributions of galaxies in the far-IR and submm. We here present the results of the first combination of Herschel and Planck fluxes of local galaxies from the Herschel Reference Sample (HRS) survey, covering galaxies at distances between 15 and 25 Mpc. This combination provides information on SEDs in eight bands from 60μm, using IRAS, to 1.4mm using Planck. We apply a similar fitting procedure to this data as applied to the Planck ERCSC-detected nearby galaxies and confirm the result that dust significantly colder than 20K is common in local galaxies. It is early days for this kind of study, but it is clear that the new generation of satellites are already adding considerably to our knowledge of the far-IR/submm properties of galaxies. [ABSTRACT FROM PUBLISHER]

We consider a model for an underpinning of the universe: there are oscillators at the Planck scale in the background dark energy. Starting from a coherent array of such oscillators it is possible to get a description from elementary particles to Black Holes including the usual Hawking-Beckenstein theory. There is also a description of Gravitation in the above model which points to a unified description with electromagnetism. [ABSTRACT FROM AUTHOR]

Abstract: The two science missions Herschel, an observatory-type mission, and Planck, a survey mission, are combined in one programme within ESA long-term science programme. Herschel, an observatory mission, will target the largely unexplored infrared and sub-millimetre part of the electromagnetic spectrum from 60 to 670μm with three scientific instruments. As a survey mission, the objective for Planck is to image systematically the whole sky simultaneously with two scientific instruments in nine frequency channels between 30 and 900GHz to unravel the temperature fluctuations, the anisotropy, of the cosmic background radiation. For both satellites, which have been launched from the European Space Port in Kourou, French Guiana, on a single Ariane 5 launcher, the orbits are Lissajous orbits around the 2nd Lagrange Point L2 of the Earth–Sun system. Having surpassed the technological problems and the validation of the instruments, this paper will recall the Herschel and Planck spacecraft''s characteristics, the mission aspects and the science requirements. The integration and acceptance verification of both spacecraft flight models being complete, this paper will highlight the development and spacecraft level acceptance tests status and focus on the major milestones up to the launch from Kourou on Ariane 5 successfully achieved on May 14, 2009. [Copyright &y& Elsevier]

We consider a model for an underpinning of the universe: there are oscillators at the Planck scale in the background dark energy. Starting from a coherent array of such oscillators it is possible to get a description from elementary particles to Black Holes including the usual Hawking-Beckenstein theory. There is also a characterization of Gravitation in the above model which points to a unified description with electromagnetism. [ABSTRACT FROM AUTHOR]

In this paper we investigate the constraints on the cosmological parameters, especially the equation of state of dynamical dark energy wDE, the inflationary parameters ns, αs and r, the total neutrino mass ∑ mν and the curvature of the universe ΩK, using the simulated data of future Planck measurement. First, we determine the cosmological parameters with the current observations, including ESSENCE (192 samples), Three-Year WMAP (WMAP3), Boomerang-2K2, CBI, VSA, ACBAR, SDSS LRG and 2dFGRS, and then we take the best-fit model as the fiducial model in the ensuing simulations. In the simulations we pay particular attention to the effects of the dynamical dark energy in the determination of the cosmological parameters. For this reason, in order to make our constraints more robust, we have added the simulated SNAP data to our simulations. Using the present data, we find that the Quintom dark energy model is mildly favored, while the ΛCDM model remains a good fit. In the framework of the dynamical dark energy model, the constraints on the inflationary parameters, ∑ mν and ΩK, become weak, compared with the constraints in the ΛCDM model. Intriguingly, we find that the inflationary models with a "blue" tilt, which are excluded about 2σ in the ΛCDM model, are well within the 2σ region with the presence of the dynamics of dark energy. The upper limits of neutrino mass are weakened by a factor of 2 (95% CL) — say, ∑ mν < 1.59 eV and ∑ mν < 1.53 eV for two forms of parametrization of the equation of state of dark energy. The flat universe is a good fit to the current data, namely |ΩK| < 0.03 (95% CL). With the simulated Planck and SNAP data, the dynamical dark energy model and the ΛCDM model might be distinguished at the 4σ confidence level. And the uncertainties of the inflationary parameters, ∑ mν and ΩK, can be reduced significantly in the framework of the dynamical dark energy model. We also constrain the rotation angle Δα, denoting the possible CPT violation, from the simulated Planck and CMBpol data and find that our results are much more stringent than the current constraint and will be used to verify the CPT symmetry with a higher precision. [ABSTRACT FROM AUTHOR]

The large number coincidences that fascinated theorists such as Eddington and Dirac are shown here to be a specific example of a general set of scaling factors defining universes in which fundamental forces are equated. The numbers have prescriptive power and they are therefore correct and exact a priori. The universes thus defined exhibit a fractal structure centred on the Planck/Stoney scale with some formal resemblance to black holes and with properties analogous to Hawking radiation. The problematic case of emerging and evaporating universes is briefly considered in the context of quantum gravity. Historically, the large numbers are associated with the mass of a charged particle and the mass of the universe. This paper demonstrates that the numbers are properly understood in the context of four masses including a non-zero mass derived from Hubble's Constant and the Planck or Stoney mass. [ABSTRACT FROM AUTHOR]

In this note we start with the Planck scale or the quantum of area which is of importance in recent quantum gravity approaches. We then deduce the gravitational constant from the theory. It turns out that gravitation has the Sakharov character of being an ‘excess’ of energy. In the process we obtain an elegant rationale for the quantum of area and an alternative expression for the Bekenstein radiation time. All results are in agreement with observation (in the order of magnitude sense). [ABSTRACT FROM AUTHOR]

Extending the result of a previous paper, wherein elementary particles were considered to be an array of Planck scale oscillators, we show that the universe itself is the normal mode of a set of Planck scale oscillators. [ABSTRACT FROM AUTHOR]

The Low Frequency Instrument aboard the Planck satellite will employ pseudo-correlation radiometers, operating over three broad bands centered at 30, 44, 70 GHz. This choice is oriented to maximize the instrumental stability reducing non-white noise effects produced inside the radiometers. The radiometer scheme allows the simultaneous comparison of two input signals, one coming from the telescope and the other coming from a reference blackbody (the “reference load” RL) at a stable temperature near 4 K. In order to minimize non-white noise, typically exhibiting a 1/f spectrum, the Reference Load temperature must be as close as possible to the sky temperature (about 2.7 K). The accuracy of the measurement is tightly related to the ability of keeping under control and minimizing all systematic effects potentially perturbing the RL signal, particularly those not easily removable in software during data analysis. A model of the radiometer and RL system interface, based on the finite elements method, has been developed, together with a detailed thermal modeling, to characterize the physical system and to optimize its performance. The function of the radiometric chain, the modeling and the changes made in the baseline configuration to improve the system performances are described. The impact of systematic effects on the optimized configuration are also quantitatively investigated. [Copyright &y& Elsevier]

The main characteristics of the European Space Agency (EGA) Standard Radiation Environment Monitor (SREM) are outlined. First SREM results from the Project for On-Board Autonomy-I (PROBA-I) and INTEGRAL spacecraft are presented. [ABSTRACT FROM AUTHOR]

Planck, a European Space Agency satellite to be launched in 2007, is dedicated to surveying the full sky at sub-millimetre and millimetre wavelength. The primary goal of the mission is the final mapping of the Cosmic Microwave Background Anisotropies (CMBA). With an angular resolution of 5 arcmin and a sensitivity of ΔTCMB/TCMB=2×10−6, the Planck mission will be about 1000 times more sensitive than COBE-DMR and at least 20 times more than WMAP. Planck has also very good capabilites for measurements of polarization, although it will not exhaust the information contained in the CMBA polarization pattern. Two instruments share the Planck focal plane; the High Frequency Instrument (HFI) covers the wavelength ranging from 300 μm to 3 mm by using 48 bolometers cooled to 100 mK. This instrument is realized by an international collaboration, led by the IAS at Orsay. The other part of the relevant electromagnetic spectrum is covered by the Low Frequency Instrument (LFI) using HEMT radiometers cooled at 18 K and realized by a consortium led by the CNR in Milano. The first part of this article presents expected results of Planck on CMBA, both in intensity and polarization. In a second part, the global design of the Planck mission will be presented. We describe in particular the implications of Planck scientific goals on the instruments design, and especially on HFI that is the most sensitive Planck instrument. To cite this article: F.R. Bouchet et al., C. R. Physique 4 (2003). [Copyright &y& Elsevier]

In 1916, Einstein rederived the blackbody radiation law of Planck that originated the idea of quantized energy one hundred years ago. For this purpose, Einstein introduced the concept of transition probability, which had a profound influence on the development of quantum theory. In this article, we adopt Einstein's assumptions with two exceptions and seek the statistical condition for the thermal equilibrium of matter without referring to the inner details of either statistical thermodynamics or quantum theory. It is shown that the conditions of thermodynamic equilibrium of electromagnetic radiation and the energy balance of thermal radiation by the matter, between any of its two energy-states, not only result in Planck's radiation law and the Bohr frequency condition, but they remarkably yield the law of the statistical thermal equilibrium of matter: the Maxwell–Boltzmann distribution. Since the transition probabilities of the modern quantum theory of radiation coincide with their definition in Einstein's theory of blackbody radiation, the presented deduction of the Maxwell–Boltzmann distribution is equally valid within the bounds of modern quantum theory. Consequently, within the framework of the fundamental assumptions, the Maxwell–Boltzmann distribution of energy-states is not only a sufficient, but a necessary condition for thermal equilibrium between the matter and radiation. [ABSTRACT FROM AUTHOR]

Though the Planck scale is encountered in quantum super-string theory and quantum gravity, it is the Compton scale of elementary particles that is encountered in the physical world. An explanation for this is given in terms of Brownian processes and the duality relation. [ABSTRACT FROM AUTHOR]